65_HS1-834228961_62-HQ-83894_Serial_164
Agency: FBI

The FBI's 62-HQ-83894 case file includes investigative records, eyewitness testimonies, and public reports concerning Unidentified Flying Objects and flying discs documented between June 1947 and July 1968. The records include high-profile incident accounts, photographic evidence from sites like Oak Ridge, TN, and technical proposals regarding potential propulsion systems. Additional topics include convention programs, researcher accounts, and extensive media coverage from the period.  This file is partially posted on FBI vault with more redactions and some pages missing.  Included here is the complete case file with several newly declassified pages and only minor redactions.

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io ae @ RESTRICTED @ DEPARTMENT OF THE AIR FORCE HEADQUARTERS UNITED STATES AIR FORCE DIRECTORATE OF INTELLIGENCE WASHINGTON 25, D. C. 15 February 1949 AIR INTELLIGENCE REQUIREMENTS MEMORANDUM NUMBER 4 UNCONVENTIONAL AIRCRAFT PART I - GENERAL 1, PURPOSE The purpose of this memorandum is twofold: a. To enunciate continuing Air Force requirements for information pertaining to sightings of unconventional aircraft and unidentified flying objects, including the so-called ‘‘Flying Discs.” b. To establish procedures for reporting such information. 2. RESCISSION 2 Department of the Army Collection Memorandum Number 7, dated 21 January 1948, and letter, CSGID 425.1, dated 25 March 1948, both subject as above, which have been transferred to Air Force agencies for action, are herewith superseded. 8. REPORTING a. General (1) As complete an answer to the requirements enunciated in Part Il, as may be procur- able, should be dispatched by means of electrical transmission immediately after sightings. (2) Supplementary reports should be forwarded as available by the most expeditious means consistent with the importance of the information reported. b. Major Air Commands (Overseas) and Air Attaches (1) Initial and supplementary cabled reports will be transmitted to the Director of Intelli- gence, Headquarters United States Air Force. Cables will contain the phase, ‘Pass to COMGENAMC WRIGHT-PATTERSON AFB, DAYTON, OHIO, ATTN: MCIAXO-3.”’ ENCLOSURE BS RESTRICTED 9-892, AF

@ =-kestricteo @ eesti (2) Supplementary written reports, prepared on AF Form 112, will be forwarded to the Director of Intelligence, Headquarters United States Air Force. (3) Commanding General, Air Materiel Command is authorized direct contact with major Air Commands (overseas) and organizations under their control in connection with the development of information on this subject. ce. Major Air Commands (ZI) (1) Reports will be forwarded direct to the Commanding General, Air Materiel Command, Wright-Patterson Air Force Base, Dayton, Ohio, Attn: MCIAXO-3 by installations receiv- ing information pertaining to the requirements enunciated in Part II. ; ' (2) Copies of such reports may be supplied the Command Headquarters of the installation concerned. (3) A copy of all reports sent to Air Materiel Command in accordance with these instruc- tions will be forwarded at the same time to the Director of Intelligence, Headquarters United States Air Force. (4) Written reports will be submitted on AF Form 112. (5) Commanding General, Air Materiel Command is authorized direct contact with major Air Commands (ZI) and organizations under their control in connection with the develop- ment of information on this subject. d. Non-Air Force Agencies (1) Addressees other than those of the United States Air Force are requested to forward reports direct to the Commanding General, Air Materiel Command, Wright-Patterson Air Force Base, Dayton, Ohio, Attn: MCIAXO-3. (2) In order to reduce the time factor involved in transmission of this type of information s it is requested that, wherever communications facilities permit, subordinate elements be authorized to communicate reports direct to the Commanding General, Air Materiel Com- Se mand. PART II - REQUIREMENTS General 1. Date of sighting. 2. Time of sighting (zonal by 24 hr. clock). 3. Where sighted (observer’s position): a. Ground (1) City, town. (2) Distance and direction from city or town, road, intersection, etc. (3) From building (story), yard, etc. (4) Map coordinates (if feasible) showing latitude and longitude. -2- RESTRICTED

rs) @ RESTRICTED @ b, Air (1) Type aircraft, speed, altitude, direction of flight. (2) Distance and direction from city, town or known landmark. (3) Clock position of object from observer’s aircraft. (4) Latitude and longitude. c. Sea (1) Latitude and longitude. (2) Proximity to land. (Name city, country, etc.) 4, Number of objects. Formation type (if any), sketch if possible. 5. Observable celestial phenomena or planets that may account for the sighting. (Local facilities or organizations which follow such celestial phenomena should be consulted for such information.) 6. Distance of object from observer. i a. Laterally or horizontally. b. Angle of elevation from horizon. c. Altitude. 7. Time in sight. 8. Appearance of object. a. Color. b. Shape. (Sketch if possible) y c. Apparent construction. (Of what material or substance) d. Size. (1) Estimated size. (2) Size as it appeared from observer’s view. (Compared to known object) 9. Direction of flight. 10. Tactics or maneuvers. Vertical ascent or descent, horizontal, oscillating, fluttering, evasive, aggressive, erratic, etc. 11. Evidence of exhaust. a. Color of smoke. ‘b. Length and width. RESTRICTED -3-

@ —=-zestricteo @ Se oe c. Odor (if any). d. Rate of evaporation. ‘ e. Does trail vary with sound? (spurts) 12. Effect on clouds. a. Opened path thru clouds. b. Forced cloud or mists. ¢. Reflected on cloud. d. Showed thru cloud. 13. Lights. a. Reflected or attached. b. Luminous ¢. Blinked on and off in relation to speed. 14. Support a. Wings. b. Aerodynamic list of fuselage. ce. Vertical jet. d. Rotating cylinder or cone. e. Aerostatic lift (balloon or dirigible). 15. Propulsion. a. Propeller or jet. ¢ b. Rotor. c. Aerodynamic vanes (flapping or oscillating) (Katz Mayer effect). d. Visible exhaust or jet openings. 16. Control and stability. a. Fins b. Stabilizers (horizontal or vertical). (1) Size. (2) Shape. (8) Location. -4- RESTRICTED

Ries? e restricten @ 17. Air ducts, a. Slots. b. Duct openings. 18. Speed - M.P.H. 19. Sound. a. Continuous whine or buzz. b. Roar, whistle, whoosh. c. Intermittent. 20. Manner of disappearance, a. Explode. (1) Possibility of fragments. (2) Other physical evidence. b. Faded from view. c. Disappeared behind obstacle. Relative to the Observer 1. Name of observer. 2. Address. 3. Occupation. 4. Place of business. a. Employer or employee. 5. Pertinent hobbies. a. Is observer amateur astronomer, pilot, engineer, etc. b. Length of time engaged in hobby (experience). 6. Ability to determine: a. Color, b. Speed of moving objects. ¢. Size at distance. 7, Reliability of observer. a. Sources. RESTRICTED -5-

@ —=-zestricteo @ eae (1) Neighbors. (2) Police Dept. (3) FBI records. (4) Employer. 8. Notes relative to observer on: a. Sightings in general. b. How attention was drawn to object(s). (1) Sound. (2) Motion. (3) Glint of light. c. Degree of fatigue and duration of flight at time of sighting in cases where observer is airborne. 9, Witnesses. a. Addressees. a b. Occupation. c. Reliability. 10. Comments of interrogator regarding the intelligence and character of person interrogated. Relative to Radar Sightings 1. Re radars operating on ground. a. Observations of range, speed, altitude and size of target. b. Did target executive any turns? If so, what angle (180°), etc. and what radius of turn. If radius of turn is not observable, how long did the target stay in the turn and what was its speed? c. Note particularly any separation of distant target into several targets upon approach. Track all if possible. 2. If airborne when object sighted. a. Were there any radar inductions or extra noise on radio circuits? b. Give estimates of size, speed, maneuvers, etc. GENERAL 1. Teletype sequences of local weather conditions. 2. Winds aloft report. -6- RESTRICTED

é ate One oe ee © nestricten @ 8. Local flight schedules of commercial, private and military aircraft flying in vicinity at the time. (Check Canadian activity if close to that border.) 4, Possible releases of testing devices in vicinity sent aloft by Ordnance, Navy, Air Force, Army, Weather Units, Research Organizations or any other. 5. If object contacted earth, obtain soil samples within and without depression or spot where object landed (and then presumably departed) for purpose of making comparison of soils. 6. If object came sufficiently near other aircraft or known objects check surfaces with Geiger counters for possible radioactivity. Make comparisons with other unaffected aircraft objects, etc. 7. Obtain photographs (or original negatives) where available; if not, secure sketches of: a. Object. b. Surrounding terrain where observed. ¢, Place where it contacted earth (if this happened). d. Maneuvers. e. Formation if objects were more than two. 8. Secure signed statement. ’ 9. Obtain fragments or physical evidence where possible. 10. Was any radio antenna to be observed, i.e., (any projections or extentions that might presum- ably be construed as such). Cc. P. CABELL Major General, USAF Director of Intelligence, Office of Deputy Chief of Staff, Operations DISTRIBUTION: Commanding Generals, Major Air Commands, ZI and Overseas All United States Air Attaches 3 Director of Central Intelligence Special Assistant for Research and Intelligence, Department of State Director of Intelligence, GSUSA Chief of Naval Intelligence Commandant (INT), United States Coast Guard Director, Federal Bureau of Investigation RESTRICTED -7-

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RESTRICTED DEPARTMENT OF THE AIR FORCE HEADQUARTERS UNITED STATES AIR FORCE DIRECTORATE OF INTELLIGENCE WASHINGTON 25, D. C. 15 February 1949 AIR INTELLIGENCE REQUIREMENTS MEMORANDUM NUMBER 4 UNCONVENTIONAL AIRCRAFT PART I - GENERAL 1. PURPOSE The purpose of this memorandum is twofold: a. To enunciate continuing Air Force requirements for information pertaining to sightings of unconventional aircraft and unidentified flying objects, including the so-called ‘‘Flying Discs.” b. To establish procedures for reporting such information. 2. RESCISSION Department of the Army Collection Memorandum Number 7, dated 21 January 1948, and letter, CSGID 425.1, dated 25 March 1948, both subject as above, which have been transferred to Air Force agencies for action, are herewith superseded. 3. REPORTING a. General (1) As complete an answer to the requirements enunciated in Part II, as may be procur- able, should be dispatched by means of electrical transmission immediately after sightings. (2) Supplementary reports should be forwarded as available by the most expeditious means consistent with the importance of the information reported b. Major Air Commands (Overseas) and Air Attaches (1) Initial and supplementary cabled reports will be transmitted to the Director of Intelli- gence, Headquarters United States Air Force. Cables will contain the phase, ‘‘Pass to COMGENAMC WRIGHT-PATTERSON AFB, DAYTON, OHIO, ATTN: MCIAXO-3.” RESTRICTED 69-4892, AF é 7

RESTRICTED (2) Supplementary written reports, prepared on AF Form 112, will be forwarded to the Director of Intelligence, Headquarters United States Air Force. (8) Commanding General, Air Materiel Command is authorized direct contact with major Air Commands (overseas) and organizations under their control in connection with the development of information on this subject. ¢. Major Air Commands (ZI) (1) Reports will be forwarded direct to the Commanding General, Air Materiel Command, Wright-Patterson Air Force Base, Dayton, Ohio, Attn: MCIAXO-3 by installations receiv- ing information pertaining to the requirements enunciated in Part Il. (2) Copies of such reports may be supplied the Command Headquarters of the installation concerned, (8) A copy of all reports sent to Air Materiel Command in accordance with these instruc- tions will be forwarded at the same time to the Director of Intelligence, Headquarters United States Air Force. (4) Written reports will be submitted on AF Form 112. (5) Commanding General, Air Materiel Command is authorized direct contact with major Air Commands (ZI) and organizations under their control in connection with the develop- ment of information on this subject. d. Non-Air Force Agencies (1) Addressees other than those of the United States Air Force are requested to forward reports direct to the Commanding General, Air Materiel Command, Wright-Patterson Air Force Base, Dayton, Ohio, Attn: MCIAXO-3. (2) In order to reduce the time factor involved in transmission of this type of information it is requested that, wherever communications facilities permit, subordinate elements be authorized to communicate reports direct to the Commanding General, Air Materiel Com- mand, PART Il - REQUIREMENTS General 1. Date of sighting. Z 2. Time of sighting (zonal by 24 hr. clock). 3. Where sighted (observer’s position): a. Ground (1) City, town. (2) Distance and direction from city or town, road, intersection, etc. (3) From building (story), yard, etc. (4) Map coordinates (if feasible) showing latitude and longitude. -2- RESTRICTED

RESTRICTED b. Air (1) Type aircraft, speed, altitude, direction of flight. (2) Distance and direction from city, town or known landmark. (8) Clock position of object from observer’s aircraft. (4) Latitude and longitude. c, Sea (1) Latitude and longitude. , (2) Proximity to land. (Name city, country, etc.) 4, Number of objects. Formation type (if any), sketch if possible. §. Observable celestial phenomena or planets that may account for the sighting. (Local facilities or organizations which follow such celestial phenomena should be consulted for such information.) 6. Distance of object from observer. a. Laterally or horizontally. b. Angle of elevation from horizon. c, Altitude. 7. Time in sight. 8. Appearance of object. a. Color. b. Shape, (Sketch if possible) c. Apparent construction. (Of what material or substance) d. Size. (1) Estimated size. (2) Size as it appeared from observer’s view. (Compared to known object) 9. Direction of flight. 10. Tactics or maneuvers. Vertical ascent or descent, horizontal, oscillating, fluttering, evasive, aggressive, erratic, etc. 11. Evidence of exhaust. a. Color of smoke. Yb, Length and width. RESTRICTED -3-

RESTRICTED c. Odor (if any). d. Rate of evaporation. e. Does trail vary with sound? (spurts) 12. Effect on clouds. a. Opened path thru clouds. b, Forced cloud or mists. c. Reflected on cloud. d. Showed thru cloud. ' 13, Lights. a. Reflected or attached. b. Luminous c. Blinked on and off in relation to speed. 14. Support a. Wings. b. Aerodynamic list of fuselage. ¢c. Vertical jet. da. Rotating cylinder or cone. e. Aerostatic lift (balloon or dirigible). 15. Propulsion. a. Propeller or jet. b. Rotor, c. Aerodynamic vanes (flapping or oscillating) (Katz Mayer effect). d. Visible exhaust or jet openings. 16. Control and stability. a. Fins b. Stabilizers (horizontal or vertical). (1) Size. (2) Shape. (3) Location. -4- RESTRICTED

RESTRICTED 17. Air ducts. a. Slots. b. Duct openings. 18. Speed - M.P.H. 19, Sound. a. Continuous whine or buzz, b. Roar, whistle, whoosh. c. Intermittent. 20. Manner of disappearance. a. Explode. (1) Possibility of fragments. (2) Other physical evidence. b, Faded from view. c. Disappeared behind obstacle. Relative to the Observer 1. Name of observer, 2. Address. 3. Occupation. 4, Place of business. a. Employer or employee. 5. Pertinent hobbies, a. Is observer amateur astronomer, pilot, engineer, etc. b. Length of time engaged in hobby (experience). 6. Ability to determine: a. Color. b. Speed of moving objects. c. Size at distance. 7. Reliability of observer. a. Sources, RESTRICTED cal pe

RESTRICTED (1) Neighbors. (2) Police Dept. (3) FBI records. (4) Employer. ‘ 8, Notes relative to observer on: a, Sightings in general. b. How attention was drawn to object(s). (1) Sound. (2) Motion. (3) Glint of light. ce, Degree of fatigue and duration of flight at time of sighting in cases where observer is airborne. 9, Witnesses. a, Addressees. b. Occupation. c. Reliability. 10. Comments of interrogator regarding the intelligence and character of person interrogated. ; Relative to Radar Sightings 1. Re radars operating on ground. a. Observations of range, speed, altitude and size of target. b. Did target executive any turns? If so, what angle (180°), etc. and what radius of turn. If radius of turn is not observable, how long did the target stay in the turn and what was its speed? c. Note particularly any separation of distant target into several targets upon approach. Track all if possible. 2, If airborne when object sighted. a. Were there any radar inductions or extra noise on radio circuits? b, Give estimates of size, speed, maneuvers, etc. GENERAL 1. Teletype sequences of local weather conditions. 2, Winds aloft report. -6- RESTRICTED

RESTRICTED 8. Local flight schedules of commercial, private and military aircraft flying in vicinity at the time. (Check Canadian activity if close to that border.) 4. Possible releases of testing devices in vicinity sent aloft by Ordnance, Navy, Air Force, Army, Weather Units, Research Organizations or any other. 5. If object contacted earth, obtain soil samples within and without depression or spot where object landed (and then presumably departed) for purpose of making comparison of soils. 6. If object came sufficiently near other aircraft or known objects check surfaces with Geiger counters for possible radioactivity. Make comparisons with other unaffected aircraft objects, etc. 7. Obtain photographs (or original negatives) where available; if not, secure sketches of: a. Object, b. Surrounding terrain where observed. ¢c. Place where it contacted earth (if this happened). d. Maneuvers. e. Formation if objects were more than two. 8. Secure signed statement. 9. Obtain fragments or physical evidence where possible. 10. Was any radio antenna to be observed, i.e., (any projections or extentions that might presum- ably be construed as such). Cc. P. CABELL Major General, USAF Director of Intelligence, Office of Deputy Chief of Staff, Operations DISTRIBUTION: Commanding Generals, Major Air Commands, ZI and Overseas All United States Air Attaches Director of Central Intelligence Special Assistant for Research and Intelligence, Department of State Director of Intelligence, GSUSA Chief of Naval Intelligence Commandant (INT), United States Coast Guard Director, Federal Bureau of Investigation RESTRICTED al at

RESTRICTED DEPARTMENT OF THE AIR FORCE HEADQUARTERS UNITED STATES AIR FORCE DIRECTORATE OF INTELLIGENCE WASHINGTON 25, D. C. 15 February 1949 AIR INTELLIGENCE REQUIREMENTS MEMORANDUM NUMBER 4 UNCONVENTIONAL AIRCRAFT PART I - GENERAL 1. PURPOSE The purpose of this memorandum is twofold: a. To enunciate continuing Air Force requirements for information pertaining to sightings of unconventional aircraft and unidentified flying objects, including the so-called “Flying Discs.” b. To establish procedures for reporting such information, 2. RESCISSION Department of the Army Collection Memorandum Number 7, dated 21 January 1948, and letter, CSGID 425.1, dated 25 March 1948, both subject as above, which have been transferred to Air Force agencies for action, are herewith superseded. 8, REPORTING a. General (1) As complete an answer to the requirements enunciated in Part II, as may be procur- able, should be dispatched by means of electrical transmission immediately after sightings. (2) Supplementary reports should be forwarded as available by the most expeditious means consistent with the importance of the information reported. b. Major Air Commands (Overseas) and Air Attaches (1) Initial and supplementary cabled reports will be transmitted to the Director of Intelli- gence, Headquarters United States Air Force. Cables will contain the phase, ‘‘Pass to COMGENAMC WRIGHT-PATTERSON AFB, DAYTON, OHIO, ATTN: MCIAXO-3.” RESTRICTED 69-4892, AF

RESTRICTED (2) Supplementary written reports, prepared on AF Form 112, will be forwarded to the Director of Intelligence, Headquarters United States Air Force. (83) Commanding General, Air Materiel Command is authorized direct contact with major Air Commands (overseas) and organizations under their control in connection with the development of information on this subject. ¢. Major Air Commands (ZI) (1) Reports will be forwarded direct to the Commanding General, Air Materiel Command, Wright-Patterson Air Force Base, Dayton, Ohio, Attn: MCIAXO-3 by installations receiv- ing information pertaining to the requirements enunciated in Part Il. (2) Copies of such reports may be supplied the Command Headquarters of the installation concerned, (3) A copy of all reports sent to Air Materiel Command in accordance with these instruc- tions will be forwarded at the same time to the Director of Intelligence, Headquarters United States Air Force. (4) Written reports will be submitted on AF Form 112, (5) Commanding General, Air Materiel Command is authorized direct contact with major Air Commands (ZI) and organizations under their control in connection with the develop- ment of information on this subject. d. Non-Air Force Agencies (1) Addressees other than those of the United States Air Force are requested to forward reports direct to the Commanding General, Air Materiel Command, Wright-Patterson Air Force Base, Dayton, Ohio, Attn: MCIAXO-3. (2) In order to reduce the time factor involved in transmission of this type of information it is requested that, wherever communications facilities permit, subordinate elements be authorized to communicate reports direct to the Commanding General, Air Materiel Com- mand, PART II - REQUIREMENTS General 1. Date of sighting. 2. Time of sighting (zonal by 24 hr. clock). 8. Where sighted (observer’s position): a. Ground (1) City, town, (2) Distance and direction from city or town, road, intersection, etc. (3) From building (story), yard, etc. (4) Map coordinates (if feasible) showing latitude and longitude. -2- RESTRICTED

RESTRICTED b. Air (1) Type aircraft, speed, altitude, direction of flight. (2) Distance and direction from city, town or known landmark. (8) Clock position of object from observer’s aircraft. (4) Latitude and longitude, ce, Sea (1) Latitude and longitude. (2) Proximity to land. (Name city, country, etc.) 4. Number of objects. Formation type (if any), sketch if possible. 5. Observable celestial phenomena or planets that may account for the sighting. (Local facilities or organizations which follow such celestial phenomena should be consulted for such information.) 6. Distance of object from observer. a. Laterally or horizontally. b. Angle of elevation from horizon. c. Altitude. 7. Time in sight. 8. Appearance of object. a. Color. b. Shape. (Sketch if possible) c. Apparent construction. (Of what material or substance) d, Size, (1) Estimated size. (2) Size as it appeared from observer’s view. (Compared to known object) 9. Direction of flight. 10, Tactics or maneuvers. Vertical ascent or descent, horizontal, oscillating, fluttering, evasive, aggressive, erratic, etc. 11, Evidence of exhaust. a, Color of smoke. yb. Length and width. RESTRICTED -8-

RESTRICTED ce. Odor (if any), d. Rate of evaporation. e. Does trail vary with sound? (spurts) 12, Effect on clouds, a. Opened path thru clouds. b. Forced cloud or mists, c. Reflected on cloud. d, Showed thru cloud. 13. Lights. a, Reflected or attached. b. Luminous c. Blinked on and off in relation to speed. 14, Support a, Wings. b. Aerodynamic list of fuselage. c. Vertical jet. d. Rotating cylinder or cone. i e. Aerostatic lift (balloon or dirigible). 15. Propulsion. a. Propeller or jet. b. Rotor. c. Aerodynamic vanes (flapping or oscillating) (Katz Mayer effect). d, Visible exhaust or jet openings. 16, Control and stability. a. Fins b, Stabilizers (horizontal or vertical). (1) Size. (2) Shape. (8) Location. -4- RESTRICTED

RESTRICTED 17, Air ducts. a. Slots. b. Duct openings. 18. Speed - M.P.H. 19. Sound. a. Continuous whine or buzz. b. Roar, whistle, whoosh. ec. Intermittent. 20. Manner of disappearance. a. Explode. (1) Possibility of fragments. (2) Other physical evidence. b. Faded from view. c. Disappeared behind obstacle. Relative to the Observer 1, Name of observer. 2, Address, 3. Occupation. 4, Place of business. a. Employer or employee. 5. Pertinent hobbies, a. Is observer amateur astronomer, pilot, engineer, etc. b. Length of time engaged in hobby (experience), 6, Ability to determine: a. Color, b. Speed of moving objects. c. Size at distance. 7. Reliability of observer. a. Sources. RESTRICTED ry

RESTRICTED (1) Neighbors. (2) Police Dept. (3) FBI records. (4) Employer. 8. Notes relative to observer on: a. Sightings in general. b. How attention was drawn to object(s). (1) Sound. (2) Motion. (3) Glint of light. c. Degree of fatigue and duration of flight at time of sighting in cases where observer is airborne, 9. Witnesses. a. Addressees. b. Occupation. c. Reliability. 10. Comments of interrogator regarding the intelligence and character of person interrogated. Relative to Radar Sightings 1. Re radars operating on ground. a, Observations of range, speed, altitude and size of target. b, Did target executive any turns? If so, what angle (180°), etc. and what radius of turn. If radius of turn is not observable, how long did the target stay in the turn and what was its speed? c. Note particularly any separation of distant target into several targets upon approach. Track all if possible, 2. If airborne when object sighted. a. Were there any radar inductions or extra noise on radio circuits? b. Give estimates of size, speed, maneuvers, etc. GENERAL 1. Teletype sequences of local weather conditions. 2. Winds aloft report. -6- RESTRICTED

RESTRICTED 8. Local flight schedules of commercial, private and military aircraft flying in vicinity at the time. (Check Canadian activity if close to that border.) 4. Possible releases of testing devices in vicinity sent aloft by Ordnance, Navy, Air Force, Army, Weather Units, Research Organizations or any other. 5. If object contacted earth, obtain soil samples within and without depression or spot where object landed (and then presumably departed) for purpose of making comparison of soils. 6, If object came sufficiently near other aircraft or known objects check surfaces with Geiger counters for possible radioactivity. Make comparisons with other unaffected aircraft objects, etc. 7. Obtain photographs (or original negatives) where available; if not, secure sketches of: a. Object. b. Surrounding terrain where observed, c. Place where it contacted earth (if this happened). d, Maneuvers. e. Formation if objects were more than two. 8. Secure signed statement. 9. Obtain fragments or physical evidence where possible. 10. Was any radio antenna to be observed, i.e., (any projections or extentions that might presum- ably be construed as such). Cc. P, CABELL Major General, USAF Director of Intelligence, Office of Deputy Chief of Staff, Operations 7 DISTRIBUTION: Commanding Generals, Major Air Commands, ZI and Overseas All United States Air Attaches Director of Central Intelligence Special Assistant for Research and Intelligence, Department of State Director of Intelligence, GSUSA Chief of Naval Intelligence Commandant (INT), United States Coast Guard Director, Federal Bureau of Investigation RESTRICTED Cy fies

RESTRICTED DEPARTMENT OF THE AIR FORCE HEADQUARTERS UNITED STATES AIR FORCE DIRECTORATE OF INTELLIGENCE WASHINGTON 25, D. C. 15 February 1949 AIR INTELLIGENCE REQUIREMENTS MEMORANDUM NUMBER 4 UNCONVENTIONAL AIRCRAFT PART I - GENERAL 1, PURPOSE The purpose of this memorandum is twofold: a. To enunciate continuing Air Force requirements for information pertaining to sightings of unconventional aircraft and unidentified flying objects, including the so-called ‘‘Flying Discs.” b. To establish procedures for reporting such information, 2. RESCISSION Department of the Army Collection Memorandum Number 7, dated 21 January 1948, and letter, CSGID 425.1, dated 25 March 1948, both subject as above, which have been transferred to Air Force agencies for action, are herewith superseded. 3. REPORTING a. General (1) As complete an answer to the requirements enunciated in Part II, as may be procur- able, should be dispatched by means of electrical transmission immediately after sightings. (2) Supplementary reports should be forwarded as available by the most expeditious means consistent with the importance of the information reported. b. Major Air Commands (Overseas) and Air Attaches (1) Initial and supplementary cabled reports will be transmitted to the Director of Intelli- gence, Headquarters United States Air Force. Cables will contain the phase, ‘‘Pass to COMGENAMC WRIGHT-PATTERSON AFB, DAYTON, OHIO, ATTN: MCIAXO-3.”’ RESTRICTED c9-4892, AF 4-846 +7 ¥Y

RESTRICTED (2) Supplementary written reports, prepared on AF Form 112, will be forwarded to the Director of Intelligence, Headquarters United States Air Force. (3) Commanding General, Air Materiel Command is authorized direct contact with major Air Commands (overseas) and organizations under their control in connection with the development of information on this subject. c. Major Air Commands (ZI) (1) Reports will be forwarded direct to the Commanding General, Air Materiel Command, Wright-Patterson Air Force Base, Dayton, Ohio, Attn: MCIAXO-3 by installations receiv- ing information pertaining to the requirements enunciated in Part II. (2) Copies of such reports may be supplied the Command Headquarters of the installation concerned. (3) A copy of all reports sent to Air Materiel Command in accordance with these instruc- tions will be forwarded at the same time to the Director of Intelligence, Headquarters United States Air Force. (4) Written reports will be submitted on AF Form 112. (5) Commanding General, Air Materiel Command is authorized direct contact with major Air Commands (ZI) and organizations under their contro] in connection with the develop- ment of information on this subject. d. Non-Air Force Agencies (1) Addressees other than those of the United States Air Force are requested to forward reports direct to the Commanding General, Air Materiel Command, Wright-Patterson Air Force Base, Dayton, Ohio, Attn: MCIAXO-3. (2) In order to reduce the time factor involved in transmission of this type of information it is requested that, wherever communications facilities permit, subordinate elements be authorized to communicate reports direct to the Commanding General, Air Materiel Com- mand, PART II - REQUIREMENTS General 1. Date of sighting. 4 2. Time of sighting (zonal by 24 hr. clock). 8. Where sighted (observer’s position): a. Ground (1) City, town. (2) Distance and direction from city or town, road, intersection, etc. (3) From building (story), yard, etc. (4) Map coordinates (if feasible) showing latitude and longitude. -2- RESTRICTED

RESTRICTED b. Air (1) Type aircraft, speed, altitude, direction of flight. (2) Distance and direction from city, town or known landmark. (8) Clock position of object from observer’s aircraft. (4) Latitude and longitude. (1) Latitude and longitude. ’ (2) Proximity to land. (Name city, country, etc.) 4, Number of objects. Formation type (if any), sketch if possible. 5. Observable celestial phenomena or planets that may account for the sighting. (Local facilities or organizations which follow such celestial phenomena should be consulted for such information.) 6. Distance of object from observer. a. Laterally or horizontally. b. Angle of elevation from horizon. c. Altitude. 7. Time in sight. 8. Appearance of object. a. Color. b. Shape. (Sketch if possible) c. Apparent construction. (Of what material or substance) d, Size. (1) Estimated size. (2) Size as it appeared from observer’s view. (Compared to known object) 9. Direction of flight. 10. Tactics or maneuvers. Vertical ascent or descent, horizontal, oscillating, fluttering, evasive, aggressive, erratic, etc. 11, Evidence of exhaust. a. Color of smoke. ’b. Length and width. RESTRICTED -3-

RESTRICTED ce, Odor (if any). d. Rate of evaporation. e. Does trail vary with sound? (spurts) 12, Effect on clouds. a, Opened path thru clouds. b. Forced cloud or mists. c. Reflected on cloud. d. Showed thru cloud. / 18. Lights. a. Reflected or attached. b, Luminous c. Blinked on and off in relation to speed. 14, Support a. Wings. b. Aerodynamic list of fuselage. c. Vertical jet. da. Rotating cylinder or cone. e. Aerostatic lift (balloon or dirigible). 15. Propulsion. a. Propeller or jet. b, Rotor, c. Aerodynamic vanes (flapping or oscillating) (Katz Mayer effect). d. Visible exhaust or jet openings. 16, Control and stability. a. Fins b. Stabilizers (horizontal or vertical). (1) Size. (2) Shape. (3) Location. -4- RESTRICTED

RESTRICTED 17. Air ducts. a. Slots. b. Duct openings. 18. Speed - M.P.H. 19. Sound. a. Continuous whine or buzz. b. Roar, whistle, whoosh. c. Intermittent. 20. Manner of disappearance. a. Explode, (1) Possibility of fragments. (2) Other physical evidence. b. Faded from view. c. Disappeared behind obstacle. Relative to the Observer 1. Name of observer. 2. Address. 8. Occupation. 4, Place of business. a. Employer or employee. 5. Pertinent hobbies, a. Is observer amateur astronomer, pilot, engineer, etc. b. Length of time engaged in hobby (experience). 6. Ability to determine: a. Color. b. Speed of moving objects. ce. Size at distance, 7, Reliability of observer. a. Sources. RESTRICTED -5-

RESTRICTED (1) Neighbors. (2) Police Dept. (3) FBI records. (4) Employer. ° 8. Notes relative to observer on: a, Sightings in general. b. How attention was drawn to object(s). (1) Sound. (2) Motion. (3) Glint of light. c. Degree of fatigue and duration of flight at time of sighting in cases where observer is airborne. 9. Witnesses, a. Addressees. b. Occupation. c. Reliability. 10. Comments of interrogator regarding the intelligence and character of person interrogated. Relative to Radar Sightings 1. Re radars operating on ground. a. Observations of range, speed, altitude and size of target. b. Did target executive any turns? If so, what angle (180°), etc. and what radius of turn. If radius of turn is not observable, how long did the target stay in the turn and what was its speed? ¢. Note particularly any separation of distant target into several targets upon approach. Track all if possible. 2, If airborne when object sighted. a. Were there any radar inductions or extra noise on radio circuits? b. Give estimates of size, speed, maneuvers, etc. GENERAL 1. Teletype sequences of local weather conditions. 2, Winds aloft report. -6- RESTRICTED

RESTRICTED 3. Local flight schedules of commercial, private and military aircraft flying in vicinity at the time. (Check Canadian activity if close to that border.) 4, Possible releases of testing devices in vicinity sent aloft by Ordnance, Navy, Air Force, Army, Weather Units, Research Organizations or any other. 5, If object contacted earth, obtain soil samples within and without depression or spot where object landed (and then presumably departed) for purpose of making comparison of soils. 6. If object came sufficiently near other aircraft or known objects check surfaces with Geiger counters for possible radioactivity. Make comparisons with other unaffected aircraft objects, etc. 7, Obtain photographs (or original negatives) where available; if not, secure sketches of: a. Object. b. Surrounding terrain where observed. ¢. Place where it contacted earth (if this happened). d, Maneuvers. e. Formation if objects were more than two. 8, Secure signed statement. 9, Obtain fragments or physical evidence where possible. 10. Was any radio antenna to be observed, i.e., (any projections or extentions that might presum- ably be construed as such), Cc. P, CABELL Major General, USAF Director of Intelligence, Office of Deputy Chief of Staff, Operations DISTRIBUTION: Commanding Generals, Major Air Commands, ZI and Overseas All United States Air Attaches Director of Central Intelligence Special Assistant for Research and Intelligence, Department of State Director of Intelligence, GSUSA Chief of Naval Intelligence Commandant (INT), United States Coast Guard Director, Federal Bureau of Investigation RESTRICTED -7-

RESTRICTED ‘ DEPARTMENT OF THE AIR FORCE HEADQUARTERS UNITED STATES AIR FORCE DIRECTORATE OF INTELLIGENCE WASHINGTON 25, D. C. 15 February 1949 AIR INTELLIGENCE REQUIREMENTS MEMORANDUM NUMBER 4 UNCONVENTIONAL AIRCRAFT PART I - GENERAL 1. PURPOSE The purpose of this memorandum is twofold: a. To enunciate continuing Air Force requirements for information pertaining to sightings of unconventional aircraft and unidentified flying objects, including the so-called “Flying Discs.” b. To establish procedures for reporting such information. 2. RESCISSION Department of the Army Collection Memorandum Number 7, dated 21 January 1948, and letter, CSGID 425.1, dated 25 March 1948, both subject as above, which have been transferred to Air Force agencies for action, are herewith superseded. 8. REPORTING a, General (1) As complete an answer to the requirements enunciated in Part II, as may be procur- able, should be dispatched by means of electrical transmission immediately after sightings. (2) Supplementary reports should be forwarded as available by the most expeditious means consistent with the importance of the information reported. b. Major Air Commands (Overseas) and Air Attaches (1) Initial and supplementary cabled reports will be transmitted to the Director of Intelli- gence, Headquarters United States Air Force. Cables will contain the phase, ‘‘Pass to COMGENAMC WRIGHT-PATTERSON AFB, DAYTON, OHIO, ATTN: MCIAXO-3.” RESTRICTED c9-4892, AF

RESTRICTED (2) Supplementary written reports, prepared on AF Form 112, will be forwarded to the Director of Intelligence, Headquarters United States Air Force. (3) Commanding General, Air Materiel Command is authorized direct contact with major Air Commands (overseas) and organizations under their control in connection with the development of information on this subject. ¢. Major Air Commands (ZI) (1) Reports will be forwarded direct to the Commanding General, Air Materiel Command, Wright-Patterson Air Force Base, Dayton, Ohio, Attn: MCIAXO-3 by installations receiv- ing information pertaining to the requirements enunciated in Part II. (2) Copies of such reports may be supplied the Command Headquarters of the installation concerned, (8) A copy of all reports sent to Air Materiel Command in accordance with these instruc- tions will be forwarded at the same time to the Director of Intelligence, Headquarters United States Air Force. (4) Written reports will be submitted on AF Form 112. (5) Commanding General, Air Materiel Command is authorized direct contact with major Air Commands (ZI) and organizations under their control in connection with the develop- ment of information on this subject. d. Non-Air Force Agencies (1) Addressees other than those of the United States Air Force are requested to forward reports direct to the Commanding General, Air Materiel Command, Wright-Patterson Air Force Base, Dayton, Ohio, Attn: MCIAXO-3, (2) In order to reduce the time factor involved in transmission of this type of information it is requested that, wherever communications facilities permit, subordinate elements be authorized to communicate reports direct to the Commanding General, Air Materiel Com- mand, PART I - REQUIREMENTS General 1. Date of sighting. 2. Time of sighting (zonal by 24 hr. clock), 3. Where sighted (observer’s position): a. Ground (1) City, town. (2) Distance and direction from city or town, road, intersection, etc. (3) From building (story), yard, etc. (4) Map coordinates (if feasible) showing latitude and longitude. = 2s RESTRICTED

RESTRICTED (1) Type aircraft, speed, altitude, direction of flight. (2) Distance and direction from city, town or known landmark. (8) Clock position of object from observer’s aircraft. (4) Latitude and longitude. c. Sea (1) Latitude and longitude. (2) Proximity to land. (Name city, country, etc.) 4. Number of objects. Formation type (if any), sketch if possible. 5. Observable celestial phenomena or planets that may account for the sighting. (Local facilities or organizations which follow such celestial phenomena should be consulted for such information.) 6. Distance of object from observer. a, Laterally or horizontally. b. Angle of elevation from horizon. c. Altitude. 7. Time in sight. 8. Appearance of object. a. Color. b. Shape. (Sketch if possible) c. Apparent construction. (Of what material or substance) d. Size. (1) Estimated size. (2) Size as it appeared from observer’s view. (Compared to known object) 9. Direction of flight. 10. Tactics or maneuvers, Vertical ascent or descent, horizontal, oscillating, fluttering, evasive, aggressive, erratic, etc. 11. Evidence of exhaust. a. Color of smoke. yb. Length and width. RESTRICTED -3-

RESTRICTED c. Odor (if any). d, Rate of evaporation. e. Does trail vary with sound? (spurts) 12. Effect on clouds. a. Opened path thru clouds. b. Forced cloud or mists. c. Reflected on cloud. d, Showed thru cloud. 18, Lights. a. Reflected or attached. b, Luminous c. Blinked on and off in relation to speed. 14. Support a, Wings. b. Aerodynamic list of fuselage. c. Vertical jet. da. Rotating cylinder or cone. le e. Aerostatic lift (balloon or dirigible). 15, Propulsion. a. Propeller or jet. b. Rotor. c. Aerodynamic vanes (flapping or oscillating) (Katz Mayer effect). d. Visible exhaust or jet openings. 16, Control and stability. a. Fins b. Stabilizers (horizontal or vertical). (1) Size. (2) Shape. (3) Location. -4- RESTRICTED

RESTRICTED 17, Air ducts. a. Slots. b. Duct openings. 18, Speed - M.P.H. 19, Sound. a. Continuous whine or buzz. b. Roar, whistle, whoosh. ¢. Intermittent. 20, Manner of disappearance. a. Explode, (1) Possibility of fragments. (2) Other physical evidence. b. Faded from view. c. Disappeared behind obstacle. Relative to the Observer 1. Name of observer. 2, Address, 3. Occupation. 4. Place of business. a. Employer or employee. 5. Pertinent hobbies. a. Is observer amateur astronomer, pilot, engineer, etc. b. Length of time engaged in hobby (experience), 6. Ability to determine: a. Color. b. Speed of moving objects. c. Size at distance, 7. Reliability of observer. a. Sources, RESTRICTED -5=

RESTRICTED (1) Neighbors. (2) Police Dept. (3) FBI records. (4) Employer. 8. Notes relative to observer on: a. Sightings in general. b. How attention was drawn to object(s). (1) Sound. (2) Motion, (3) Glint of light. c, Degree of fatigue and duration of flight at time of sighting in cases where observer is airborne. 9. Witnesses. a. Addressees. b. Occupation. c. Reliability. 10, Comments of interrogator regarding the intelligence and character of person interrogated. Relative to Radar Sightings 1. Re radars operating on ground. a. Observations of range, speed, altitude and size of target. b. Did target executive any turns? If so, what angle (180°), etc. and what radius of turn. If radius of turn is not observable, how long did the target stay in the turn and what was its speed? c. Note particularly any separation of distant target into several targets upon approach. Track all if possible. 2, If airborne when object sighted. a. Were there any radar inductions or extra noise on radio circuits? b. Give estimates of size, speed, maneuvers, etc. GENERAL 1, Teletype sequences of local weather conditions. 2, Winds aloft report. -6- RESTRICTED

RESTRICTED 8. Local flight schedules of commercial, private and military aircraft flying in vicinity at the time. (Check Canadian activity if close to that border.) 4, Possible releases of testing devices in vicinity sent aloft by Ordnance, Navy, Air Force, Army, Weather Units, Research Organizations or any other. 5. If object contacted earth, obtain soil samples within and without depression or spot where object landed (and then presumably departed) for purpose of making comparison of soils. 6, If object came sufficiently near other aircraft or known objects check surfaces with Geiger counters for possible radioactivity, Make comparisons with other unaffected aircraft objects, etc. 7, Obtain photographs (or original negatives) where available; if not, secure sketches of: a. Object. b. Surrounding terrain where observed. ce, Place where it contacted earth (if this happened). d, Maneuvers. e. Formation if objects were more than two. 8. Secure signed statement. 9, Obtain fragments or physical evidence where possible. 10. Was any radio antenna to be observed, i.e., (any projections or extentions that might presum- ably be construed as such). Cc. P. CABELL Major General, USAF Director of Intelligence, Office of Deputy Chief of Staff, Operations DISTRIBUTION: Commanding Generals, Major Air Commands, ZI and Overseas All United States Air Attaches Director of Central Intelligence Special Assistant for Research and Intelligence, Department of State Director of Intelligence, GSUSA Chief of Naval Intelligence Commandant (INT), United States Coast Guard Director, Federal Bureau of Investigation RESTRICTED -7-

RESTRICTED DEPARTMENT OF THE AIR FORCE HEADQUARTERS UNITED STATES AIR FORCE DIRECTORATE OF INTELLIGENCE WASHINGTON 25, D. C. 15 February 1949 AIR INTELLIGENCE REQUIREMENTS MEMORANDUM NUMBER 4 UNCONVENTIONAL AIRCRAFT PART I - GENERAL 1. PURPOSE The purpose of this memorandum is twofold: a. To enunciate continuing Air Force requirements for information pertaining to sightings of unconventional aircraft and unidentified flying objects, including the so-called ‘‘Flying Discs.” b. To establish procedures for reporting such information. 2, RESCISSION Department of the Army Collection Memorandum Number 7, dated 21 January 1948, and letter, CSGID 425.1, dated 25 March 1948, both subject as above, which have been transferred to Air Force agencies for action, are herewith superseded. 3. REPORTING a. General (1) As complete an answer to the requirements enunciated in Part II, as may be procur- able, should be dispatched by means of electrical transmission immediately after sightings. (2) Supplementary reports should be forwarded as available by the most expeditious means consistent with the importance of the information reported. b. Major Air Commands (Overseas) and Air Attaches (1) Initial and supplementary cabled reports will be transmitted to the Director of Intelli- gence, Headquarters United States Air Force. Cables will contain the phase, ‘‘Pass to COMGENAMC WRIGHT-PATTERSON AFB, DAYTON, OHIO, ATTN: MCIAXO-3,’’ RESTRICTED C9-4892, AF

RESTRICTED (2) Supplementary written reports, prepared on AF Form 112, will be forwarded to the Director of Intelligence, Headquarters United States Air Force. (3) Commanding General, Air Materiel Command is authorized direct contact with major Air Commands (overseas) and organizations under their control in connection with the development of information on this subject. ¢c. Major Air Commands (ZI) (1) Reports will be forwarded direct to the Commanding General, Air Materiel Command, Wright-Patterson Air Force Base, Dayton, Ohio, Attn: MCIAXO-3 by installations receiv- ing information pertaining to the requirements enunciated in Part II. (2) Copies of such reports may be supplied the Command Headquarters of the installation concerned, (8) A copy of all reports sent to Air Materiel Command in accordance with these instruc- tions will be forwarded at the same time to the Director of Intelligence, Headquarters United States Air Force. (4) Written reports will be submitted on AF Form 112. (5) Commanding General, Air Materiel Command is authorized direct contact with major Air Commands (ZI) and organizations under their control in connection with the develop- ment of information on this subject. d. Non-Air Force Agencies (1) Addressees other than those of the United States Air Force are requested to forward reports direct to the Commanding General, Air Materiel Command, Wright-Patterson Air Force Base, Dayton, Ohio, Attn: MCIAXO-3. (2) In order to reduce the time factor involved in transmission of this type of information it is requested that, wherever communications facilities permit, subordinate elements be authorized to communicate reports direct to the Commanding General, Air Materiel Com- mand, PART II - REQUIREMENTS General 1. Date of sighting. J 2. Time of sighting (zonal by 24 hr. clock). 8. Where sighted (observer’s position): a. Ground (1) City, town. (2) Distance and direction from city or town, road, intersection, etc. (8) From building (story), yard, etc, (4) Map coordinates (if feasible) showing latitude and longitude. -2- RESTRICTED

RESTRICTED b. Air (1) Type aircraft, speed, altitude, direction of flight. (2) Distance and direction from city, town or known landmark. (8) Clock position of object from observer’s aircraft. (4) Latitude and longitude. c. Sea (1) Latitude and longitude. , (2) Proximity to land. (Name city, country, etc.) 4, Number of objects. Formation type (if any), sketch if possible. 5. Observable celestial phenomena or planets that may account for the sighting. (Local facilities or organizations which follow such celestial phenomena should be consulted for such information.) 6. Distance of object from observer. a. Laterally or horizontally. b. Angle of elevation from horizon. c. Altitude. 7. Time in sight. 8. Appearance of object. a. Color, b. Shape. (Sketch if possible) c. Apparent construction. (Of what material or substance) d. Size, (1) Estimated size. (2) Size as it appeared from observer’s view. (Compared to known object) 9. Direction of flight. 10. Tactics or maneuvers. Vertical ascent or descent, horizontal, oscillating, fluttering, evasive, aggressive, erratic, etc. 11, Evidence of exhaust. a. Color of smoke, yb. Length and width. RESTRICTED -3-

RESTRICTED c. Odor (if any). d. Rate of evaporation. e. Does trail vary with sound? (spurts) 12, Effect on clouds. a. Opened path thru clouds, b. Forced cloud or mists, c. Reflected on cloud. d. Showed thru cloud. ‘ 13. Lights. a. Reflected or attached. b. Luminous c. Blinked on and off in relation to speed. 14, Support a. Wings. b, Aerodynamic list of fuselage. ¢c. Vertical jet. d. Rotating cylinder or cone. e. Aerostatic lift (balloon or dirigible). 15. Propulsion. a. Propeller or jet. b, Rotor. c. Aerodynamic vanes (flapping or oscillating) (Katz Mayer effect). d. Visible exhaust or jet openings. 16. Control and stability. a. Fins b. Stabilizers (horizontal or vertical). (1) Size. (2) Shape. (3) Location. -4- RESTRICTED

RESTRICTED 17. Air ducts. a. Slots. b. Duct openings. 18. Speed - M.P.H. 19. Sound. a. Continuous whine or buzz. b. Roar, whistle, whoosh. c. Intermittent. 20. Manner of disappearance. a. Explode. (1) Possibility of fragments. (2) Other physical evidence b. Faded from view. c. Disappeared behind obstacle. Relative to the Observer 1, Name of observer. 2, Address. 3. Occupation. 4, Place of business. a. Employer or employee. 5. Pertinent hobbies. a. Is observer amateur astronomer, pilot, engineer, etc. b. Length of time engaged in hobby (experience), 6. Ability to determine: a. Color, b. Speed of moving objects. c, Size at distance. 7. Reliability of observer. a. Sources. RESTRICTED -6-

RESTRICTED (1) Neighbors. (2) Police Dept. (3) FBI records. (4) Employer. 5 8, Notes relative to observer on: a, Sightings in general. b. How attention was drawn to object(s). (1) Sound. (2) Motion. (3) Glint of light. c. Degree of fatigue and duration of flight at time of sighting in cases where observer is airborne, 9. Witnesses. a, Addressees. b. Occupation. c. Reliability. 10. Comments of interrogator regarding the intelligence and character of person interrogated. y Relative to Radar Sightings 1. Re radars operating on ground, a. Observations of range, speed, altitude and size of target. b. Did target executive any turns? If so, what angle (180°), etc. and what radius of turn. If radius of turn is not observable, how long did the target stay in the turn and what was its speed? c. Note particularly any separation of distant target into several targets upon approach. Track all if possible. 2. If airborne when object sighted. a, Were there any radar inductions or extra noise on radio circuits? b. Give estimates of size, speed, maneuvers, etc. GENERAL 1. Teletype sequences of local weather conditions. 2. Winds aloft report. -6- RESTRICTED

RESTRICTED 3. Local flight schedules of commercial, private and military aircraft flying in vicinity at the time. (Check Canadian activity if close to that border.) 4, Possible releases of testing devices in vicinity sent aloft by Ordnance, Navy, Air Force, Army, Weather Units, Research Organizations or any other. 5, If object contacted earth, obtain soil samples within and without depression or spot where object landed (and then presumably departed) for purpose of making comparison of soils. 6. If object came sufficiently near other aircraft or known objects check surfaces with Geiger counters for possible radioactivity. Make comparisons with other unaffected aircraft objects, etc. 7. Obtain photographs (or original negatives) where available; if not, secure sketches of: a, Object. b. Surrounding terrain where observed. c, Place where it contacted earth (if this happened). d, Maneuvers. e, Formation if objects were more than two. 8. Secure signed statement. 9. Obtain fragments or physical evidence where possible. 10. Was any radio antenna to be observed, i.e., (any projections or extentions that might presum- ably be construed as such). Cc. P. CABELL Major General, USAF Director of Intelligence, Office of Deputy Chief of Staff, Operations DISTRIBUTION: Commanding Generals, Major Air Commands, ZI and Overseas All United States Air Attaches Director of Central Intelligence Special Assistant for Research and Intelligence, Department of State Director of Intelligence, GSUSA Chief of Naval Intelligence Commandant (INT), United States Coast Guard Director, Federal Bureau of Investigation RESTRICTED -7-

RESTRICTED ; DEPARTMENT OF THE AIR FORCE HEADQUARTERS UNITED STATES AIR FORCE DIRECTORATE OF INTELLIGENCE WASHINGTON 25, D. C. 15 February 1949 AIR INTELLIGENCE REQUIREMENTS MEMORANDUM NUMBER 4 UNCONVENTIONAL AIRCRAFT PART I - GENERAL 1. PURPOSE The purpose of this memorandum is twofold: a. To enunciate continuing Air Force requirements for information pertaining to sightings of unconventional aircraft and unidentified flying objects, including the so-called “Flying Discs.” b. To establish procedures for reporting such information. 2. RESCISSION Department of the Army Collection Memorandum Number 7, dated 21 January 1948, and letter, CSGID 425.1, dated 25 March 1948, both subject as above, which have been transferred to Air Force agencies for action, are herewith superseded. 3. REPORTING a. General (1) As complete an answer to the requirements enunciated in Part Il, as may be procur- able, should be dispatched by means of electrical transmission immediately after sightings. (2) Supplementary reports should be forwarded as available by the most expeditious means consistent with the importance of the information reported. b. Major Air Commands (Overseas) and Air Attaches (1) Initial and supplementary cabled reports will be transmitted to the Director of Intelli- gence, Headquarters United States Air Force. Cables will contain the phase, ‘Pass to COMGENAMC WRIGHT-PATTERSON AFB, DAYTON, OHIO, ATTN: MCIAXO-3,” RESTRICTED 09-4892, AF Z Aa 2 Y th

RESTRICTED (2) Supplementary written reports, prepared on AF Form 112, will be forwarded to the Director of Intelligence, Headquarters United States Air Force, (8) Commanding General, Air Materiel Command is authorized direct contact with major Air Commands (overseas) and organizations under their control in connection with the development of information on this subject. ¢c. Major Air Commands (ZI) (1) Reports will be forwarded direct to the Commanding General, Air Materiel Command, Wright-Patterson Air Force Base, Dayton, Ohio, Attn: MCIAXO-3 by installations receiv- ing information pertaining to the requirements enunciated in Part Il. (2) Copies of such reports may be supplied the Command Headquarters of the installation concerned, (8) A copy of all reports sent to Air Materiel Command in accordance with these instruc- tions will be forwarded at the same time to the Director of Intelligence, Headquarters United States Air Force. (4) Written reports will be submitted on AF Form 112. (5) Commanding General, Air Materiel Command is authorized direct contact with major Air Commands (ZI) and organizations under their control in connection with the develop- ment of information on this subject. d. Non-Air Force Agencies (1) Addressees other than those of the United States Air Force are requested to forward reports direct to the Commanding General, Air Materiel Command, Wright-Patterson Air Force Base, Dayton, Ohio, Attn: MCIAXO-3. (2) In order to reduce the time factor involved in transmission of this type of information it is requested that, wherever communications facilities permit, subordinate elements be authorized to communicate reports direct to the Commanding General, Air Materiel Com- mand, PART Il - REQUIREMENTS General 1, Date of sighting. 2. Time of sighting (zonal by 24 hr. clock), 3, Where sighted (observer’s position): a. Ground (1) City, town. é (2) Distance and direction from city or town, road, intersection, etc. (3) From building (story), yard, etc. (4) Map coordinates (if feasible) showing latitude and longitude. -2- RESTRICTED

RESTRICTED b. Air (1) Type aircraft, speed, altitude, direction of flight. (2) Distance and direction from city, town or known landmark, (3) Clock position of object from observer’s aircraft. (4) Latitude and longitude. ce. Sea (1) Latitude and longitude. (2) Proximity to land. (Name city, country, etc.) 4, Number of objects. Formation type (if any), sketch if possible. 5. Observable celestial phenomena or planets that may account for the sighting. (Local facilities or organizations which follow such celestial phenomena should be consulted for such information.) 6. Distance of object from observer. a. Laterally or horizontally. b. Angle of elevation from horizon. c. Altitude. 7. Time in sight. 8. Appearance of object. a. Color. b. Shape. (Sketch if possible) c. Apparent construction. (Of what material or substance) d. Size, (1) Estimated size. (2) Size as it appeared from observer’s view. (Compared to known object) 9, Direction of flight. 10, Tactics or maneuvers. Vertical ascent or descent, horizontal, oscillating, fluttering, evasive, aggressive, erratic, etc. 11. Evidence of exhaust. a. Color of smoke. yb. Length and width. RESTRICTED -3-

RESTRICTED ¢. Odor (if any). d. Rate of evaporation, e. Does trail vary with sound? (spurts) 12, Effect on clouds. a. Opened path thru clouds. b. Forced cloud or mists. c. Reflected on cloud, da. Showed thru cloud. 13, Lights, a. Reflected or attached. b, Luminous c, Blinked on and off in relation to speed. 14. Support a, Wings, b. Aerodynamic list of fuselage. c. Vertical jet. a. Rotating cylinder or cone. 7 e. Aerostatic lift (balloon or dirigible). 15. Propulsion. a. Propeller or jet. b. Rotor. c, Aerodynamic vanes (flapping or oscillating) (Katz Mayer effect). d. Visible exhaust or jet openings. 16. Control and stability. a. Fins b. Stabilizers (horizontal or vertical). (1) Size. (2) Shape. (3) Location. -4- RESTRICTED

RESTRICTED 17. Air ducts, a. Slots. b. Duct openings. 18. Speed - M.P.H. 19, Sound. a. Continuous whine or buzz. b. Roar, whistle, whoosh. c. Intermittent. 20. Manner of disappearance. a. Explode. (1) Possibility of fragments. (2) Other physical evidence. b, Faded from view. c. Disappeared behind obstacle. Relative to the Observer 1, Name of observer. 2, Address. 3. Occupation. 4, Place of business. a. Employer or employee. 5. Pertinent hobbies. a. Is observer amateur astronomer, pilot, engineer, etc. b. Length of time engaged in hobby (experience), 6. Ability to determine: a. Color. b. Speed of moving objects. c. Size at distance. 7. Reliability of observer. a. Sources. RESTRICTED ="6 +

RESTRICTED (1) Neighbors. (2) Police Dept. (83) FBI records. (4) Employer. 8. Notes relative to observer on: a. Sightings in general. b. How attention was drawn to object(s). (1) Sound. (2) Motion. (3) Glint of light. c. Degree of fatigue and duration of flight at time of sighting in cases where observer is airborne, 9, Witnesses. a. Addressees. b. Occupation. c. Reliability. 10, Comments of interrogator regarding the intelligence and character of person interrogated. Relative to Radar Sightings 1. Re radars operating on ground. a. Observations of range, speed, altitude and size of target. b, Did target executive any turns? If so, what angle (180°), etc. and what radius of turn. If radius of turn is not observable, how long did the target stay in the turn and what was its speed? c, Note particularly any separation of distant target into several targets upon approach, Track all if possible. 2. If airborne when object sighted. a, Were there any radar inductions or extra noise on radio circuits? b. Give estimates of size, speed, maneuvers, etc. GENERAL 1. Teletype sequences of local weather conditions. 2. Winds aloft report. -6- RESTRICTED

RESTRICTED 8. Local flight schedules of commercial, private and military aircraft flying in vicinity at the time. (Check Canadian activity if close to that border.) 4, Possible releases of testing devices in vicinity sent aloft by Ordnance, Navy, Air Force, Army, Weather Units, Research Organizations or any other. 5. If object contacted earth, obtain soil samples within and without depression or spot where object landed (and then presumably departed) for purpose of making comparison of soils. 6. If object came sufficiently near other aircraft or known objects check surfaces with Geiger counters for possible radioactivity. Make comparisons with other unaffected aircraft objects, etc. 7. Obtain photographs (or original negatives) where available; if not, secure sketches of: a, Object. b. Surrounding terrain where observed. c. Place where it contacted earth (if this happened). d. Maneuvers. e. Formation if objects were more than two. 8, Secure signed statement. 9. Obtain fragments or physical evidence where possible. 10. Was any radio antenna to be observed, i.e., (any projections or extentions that might presum- ably be construed as such). Cc. P. CABELL Major General, USAF Director of Intelligence, Office of Deputy Chief of Staff, Operations DISTRIBUTION: Commanding Generals, Major Air Commands, ZI and Overseas All United States Air Attaches Director of Central Intelligence Special Assistant for Research and Intelligence, Department of State Director of Intelligence, GSUSA Chief of Naval Intelligence Commandant (INT), United States Coast Guard Director, Federal Bureau of Investigation RESTRICTED CY

RESTRICTED DEPARTMENT OF THE AIR FORCE HEADQUARTERS UNITED STATES AIR FORCE DIRECTORATE OF INTELLIGENCE WASHINGTON 25, D. C. 15 February 1949 AIR INTELLIGENCE REQUIREMENTS MEMORANDUM NUMBER 4 UNCONVENTIONAL AIRCRAFT PART I - GENERAL 1, PURPOSE The purpose of this memorandum is twofold: a. To enunciate continuing Air Force requirements for information pertaining to sightings of unconventional aircraft and unidentified flying objects, including the so-called ‘‘Flying Discs.” b. To establish procedures for reporting such information. 2. RESCISSION Department of the Army Collection Memorandum Number 7, dated 21 January 1948, and letter, CSGID 425.1, dated 25 March 1948, both subject as above, which have been transferred to Air Force agencies for action, are herewith superseded. 3. REPORTING a, General (1) As complete an answer to the requirements enunciated in Part II, as may be procur- able, should be dispatched by means of electrical transmission immediately after sightings. (2) Supplementary reports should be forwarded as available by the most expeditious means consistent with the importance of the information reported. b. Major Air Commands (Overseas) and Air Attaches (1) Initial and supplementary cabled reports will be transmitted to the Director of Intelli- gence, Headquarters United States Air Force. Cables will contain the phase, ‘‘Pass to COMGENAMC WRIGHT-PATTERSON AFB, DAYTON, OHIO, ATTN: MCIAXO-3.” RESTRICTED ¢9-4892,AF

RESTRICTED (2) Supplementary written reports, prepared on AF Form 112, will be forwarded to the Director of Intelligence, Headquarters United States Air Force. (8) Commanding General, Air Materiel Command is authorized direct contact with major Air Commands (overseas) and organizations under their control in connection with the development of information on this subject. c. Major Air Commands (ZI) (1) Reports will be forwarded direct to the Commanding General, Air Materiel Command, Wright-Patterson Air Force Base, Dayton, Ohio, Attn: MCIAXO-3 by installations receiv- ing information pertaining to the requirements enunciated in Part II. (2) Copies of such reports may be supplied the Command Headquarters of the installation concerned, (8) A copy of all reports sent to Air Materiel Command in accordance with these instruc- tions will be forwarded at the same time to the Director of Intelligence, Headquarters United States Air Force. (4) Written reports will be submitted on AF Form 112. (5) Commanding General, Air Materiel Command is authorized direct contact with major Air Commands (ZI) and organizations under their control in connection with the develop- ment of information on this subject. d. Non-Air Force Agencies (1) Addressees other than those of the United States Air Force are requested to forward reports direct to the Commanding General, Air Materiel Command, Wright-Patterson Air Force Base, Dayton, Ohio, Attn: MCIAXO-3. (2) In order to reduce the time factor involved in transmission of this type of information it is requested that, wherever communications facilities permit, subordinate elements be authorized to communicate reports direct to the Commanding General, Air Materiel Com- mand, PART I - REQUIREMENTS General 1, Date of sighting. e 2, Time of sighting (zonal by 24 hr. clock). 3. Where sighted (observer’s position): a. Ground (1) City, town, (2) Distance and direction from city or town, road, intersection, etc. (8) From building (story), yard, etc. (4) Map coordinates (if feasible) showing latitude and longitude. -2- RESTRICTED

RESTRICTED b. Air (1) ‘Type aircraft, speed, altitude, direction of flight. (2) Distance and direction from city, town or known landmark. (3) Clock position of object from observer’s aircraft. (4) Latitude and longitude. (1) Latitude and longitude. (2) Proximity to land. (Name city, country, etc.) 4, Number of objects. Formation type (if any), sketch if possible. 5. Observable celestial phenomena or planets that may account for the sighting. (Local facilities or organizations which follow such celestial phenomena should be consulted for such information.) 6. Distance of object from observer. a. Laterally or horizontally. b. Angle of elevation from horizon. c. Altitude. 7. Time in sight. 8. Appearance of object. a. Color, b. Shape. (Sketch if possible) c. Apparent construction. (Of what material or substance) d. Size. (1) Estimated size. (2) Size as it appeared from observer’s view. (Compared to known object) 9. Direction of flight. 10. Tactics or maneuvers. Vertical ascent or descent, horizontal, oscillating, fluttering, evasive, aggressive, erratic, etc. 11, Evidence of exhaust. a, Color of smoke, yb. Length and width. RESTRICTED -3-

RESTRICTED c. Odor (if any). d. Rate of evaporation. e. Does trail vary with sound? (spurts) 12, Effect on clouds. a. Opened path thru clouds. b. Forced cloud or mists. c. Reflected on cloud. d, Showed thru cloud. : 13, Lights. a. Reflected or attached. b. Luminous c. Blinked on and off in relation to speed. 14, Support a. Wings. b. Aerodynamic list of fuselage. c. Vertical jet. d. Rotating cylinder or cone. e. Aerostatic lift (balloon or dirigible). 15. Propulsion. a. Propeller or jet. b. Rotor. c. Aerodynamic vanes (flapping or oscillating) (Katz Mayer effect). d. Visible exhaust or jet openings. 16. Control and stability. a. Fins b. Stabilizers (horizontal or vertical). (1) Size. (2) Shape. (8) Location. -4- RESTRICTED

RESTRICTED 17. Air ducts. a. Slots. b. Duct openings. 18. Speed - M.P.H. 19, Sound. a. Continuous whine or buzz. b. Roar, whistle, whoosh. c. Intermittent. 20. Manner of disappearance. a. Explode. (1) Possibility of fragments. (2) Other physical evidence. b. Faded from view, ce. Disappeared behind obstacle. Relative to the Observer 1. Name of observer. 2, Address. 3. Occupation. 4, Place of business. a. Employer or employee. 5. Pertinent hobbies, a. Is observer amateur astronomer, pilot, engineer, etc. b. Length of time engaged in hobby (experience). 6. Ability to determine: a. Color. b. Speed of moving objects. c. Size at distance. 7. Reliability of observer. a, Sources. RESTRICTED “5:

RESTRICTED (1) Neighbors. (2) Police Dept. (3) FBI records. (4) Employer. g 8, Notes relative to observer on: a, Sightings in general. b. How attention was drawn to object(s). (1) Sound. (2) Motion. (3) Glint of light. c. Degree of fatigue and duration of flight at time of sighting in cases where observer is airborne, 9. Witnesses. a. Addressees, b. Occupation, c. Reliability. 10. Comments of interrogator regarding the intelligence and character of person interrogated. 4 Relative to Radar Sightings 1, Re radars operating on ground. a. Observations of range, speed, altitude and size of target. b. Did target executive any turns? If so, what angle (180°), etc. and what radius of turn. If radius of turn is not observable, how long did the target stay in the turn and what was its speed? c. Note particularly any separation of distant target into several targets upon approach. Track all if possible. 2. If airborne when object sighted. a. Were there any radar inductions or extra noise on radio circuits? b. Give estimates of size, speed, maneuvers, etc. GENERAL 1. Teletype sequences of local weather conditions. 2. Winds aloft report. -6- RESTRICTED

RESTRICTED 3. Local flight schedules of commercial, private and military aircraft flying in vicinity at the time. (Check Canadian activity if close to that border.) 4, Possible releases of testing devices in vicinity sent aloft by Ordnance, Navy, Air Force, Army, Weather Units, Research Organizations or any other. 5. If object contacted earth, obtain soil samples within and without depression or spot where object landed (and then presumably departed) for purpose of making comparison of soils. 6. If object came sufficiently near other aircraft or known objects check surfaces with Geiger counters for possible radioactivity. Make comparisons with other unaffected aircraft objects, etc. 7. Obtain photographs (or original negatives) where available; if not, secure sketches of: a. Object. b. Surrounding terrain where observed. c. Place where it contacted earth (if this happened). d. Maneuvers. e. Formation if objects were more than two. 8. Secure signed statement. 9. Obtain fragments or physical evidence where possible. 10. Was any radio antenna to be observed, i.e., (any projections or extentions that might presum- ably be construed as such). Cc. P. CABELL Major General, USAF Director of Intelligence, Office of Deputy Chief of Staff, Operations DISTRIBUTION: Commanding Generals, Major Air Commands, ZI and Overseas All United States Air Attaches Director of Central Intelligence Special Assistant for Research and Intelligence, Department of State Director of Intelligence, GSUSA Chief of Naval Intelligence Commandant (INT), United States Coast Guard Director, Federal Bureau of Investigation RESTRICTED -7-

RESTRICTED i DEPARTMENT OF THE AIR FORCE HEADQUARTERS UNITED STATES AIR FORCE DIRECTORATE OF INTELLIGENCE WASHINGTON 25, D. C. 15 February 1949 AIR INTELLIGENCE REQUIREMENTS MEMORANDUM NUMBER 4 UNCONVENTIONAL AIRCRAFT PART I - GENERAL 1. PURPOSE The purpose of this memorandum is twofold: a. To enunciate continuing Air Force requirements for information pertaining to sightings of unconventional aircraft and unidentified flying objects, including the so-called “Flying Discs.” b. To establish procedures for reporting such information. 2. RESCISSION Department of the Army Collection Memorandum Number 7, dated 21 January 1948, and letter, CSGID 425.1, dated 25 March 1948, both subject as above, which have been transferred to Air Force agencies for action, are herewith superseded. 3. REPORTING a. General (1) As complete an answer to the requirements enunciated in Part Il, as may be procur- able, should be dispatched by means of electrical transmission immediately after sightings. (2) Supplementary reports should be forwarded as available by the most expeditious means consistent with the importance of the information reported. b. Major Air Commands (Overseas) and Air Attaches (1) Initial and supplementary cabled reports will be transmitted to the Director of Intelli- gence, Headquarters United States Air Force. Cables will contain the phase, ‘‘Pass to COMGENAMC WRIGHT-PATTERSON AFB, DAYTON, OHIO, ATTN: MCIAXO-3.” RESTRICTED c9-4892, AF ve € ono GW a a

RESTRICTED (2) Supplementary written reports, prepared on AF Form 112, will be forwarded to the Director of Intelligence, Headquarters United States Air Force, (3) Commanding General, Air Materiel Command is authorized direct contact with major Air Commands (overseas) and organizations under their control in connection with the development of information on this subject. ¢. Major Air Commands (ZI) (1) Reports will be forwarded direct to the Commanding General, Air Materiel Command, Wright-Patterson Air Force Base, Dayton, Ohio, Attn: MCIAXO-3 by installations receiv- ing information pertaining to the requirements enunciated in Part Il. (2) Copies of such reports may be supplied the Command Headquarters of the installation concerned, (8) A copy of all reports sent to Air Materiel Command in accordance with these instruc- tions will be forwarded at the same time to the Director of Intelligence, Headquarters United States Air Force, (4) Written reports will be submitted on AF Form 112. (5) Commanding General, Air Materiel Command is authorized direct contact with major Air Commands (ZI) and organizations under their control in connection with the develop- ment of information on this subject. d. Non-Air Force Agencies (1) Addressees other than those of the United States Air Force are requested to forward reports direct to the Commanding General, Air Materiel Command, Wright-Patterson Air Force Base, Dayton, Ohio, Attn: MCIAXO-3. (2) In order to reduce the time factor involved in transmission of this type of information it is requested that, wherever communications facilities permit, subordinate elements be authorized to communicate reports direct to the Commanding General, Air Materiel Com- mand, PART II - REQUIREMENTS General 1. Date of sighting. 2. Time of sighting (zonal by 24 hr. clock), 3, Where sighted (observer’s position): a, Ground (1) City, town. (2) Distance and direction from city or town, road, intersection, etc. (3) From building (story), yard, etc. (4) Map coordinates (if feasible) showing latitude and longitude. -2- RESTRICTED

RESTRICTED b. Air (1) Type aircraft, speed, altitude, direction of flight. (2) Distance and direction from city, town or known landmark. (3) Clock position of object from observer’s aircraft. (4) Latitude and longitude. (1) Latitude and longitude. (2) Proximity to land. (Name city, country, etc.) 4, Number of objects. Formation type (if any), sketch if possible. 6, Observable celestial phenomena or planets that may account for the sighting. (Local facilities or organizations which follow such celestial phenomena should be consulted for such information.) 6. Distance of object from observer. a. Laterally or horizontally. b. Angle of elevation from horizon. c. Altitude. 7. Time in sight. 8. Appearance of object. a. Color. b. Shape. (Sketch if possible) c. Apparent construction. (Of what material or substance) d. Size. (1) Estimated size. (2) Size as it appeared from observer’s view. (Compared to known object) 9. Direction of flight. 10. Tactics or maneuvers. Vertical ascent or descent, horizontal, oscillating, fluttering, evasive, aggressive, erratic, etc. 11. Evidence of exhaust. a, Color of smoke. yb. Length and width. RESTRICTED -3-

RESTRICTED c. Odor (if any). d. Rate of evaporation. e. Does trail vary with sound? (spurts) 12, Effect on clouds. a. Opened path thru clouds. b. Forced cloud or mists. c. Reflected on cloud. d. Showed thru cloud. 13, Lights. a, Reflected or attached. b, Luminous c. Blinked on and off in relation to speed. 14, Support a, Wings. b. Aerodynamic list of fuselage. c. Vertical jet. d, Rotating cylinder or cone. é e. Aerostatic lift (balloon or dirigible). 15. Propulsion. a. Propeller or jet. b. Rotor. c. Aerodynamic vanes (flapping or oscillating) (Katz Mayer effect). d. Visible exhaust or jet openings. 16, Control and stability. a. Fins b. Stabilizers (horizontal or vertical). (1) Size. (2) Shape. (3) Location. -4- RESTRICTED

RESTRICTED 17. Air ducts. a. Slots. b. Duct openings. 18. Speed - M.P.H. 19. Sound. a. Continuous whine or buzz. b. Roar, whistle, whoosh. c. Intermittent. 20. Manner of disappearance. a, Explode. (1) Possibility of fragments. (2) Other physical evidence. b. Faded from view. c. Disappeared behind obstacle. Relative to the Observer 1, Name of observer. 2, Address. 8. Occupation. 4, Place of business. a. Employer or employee. 5. Pertinent hobbies. a. Is observer amateur astronomer, pilot, engineer, etc. b. Length of time engaged in hobby (experience). 6. Ability to determine: a. Color, b. Speed of moving objects. c, Size at distance, 7. Reliability of observer. a. Sources. RESTRICTED -5-

RESTRICTED (1) Neighbors. (2) Police Dept. (3) FBI records. (4) Employer. 8, Notes relative to observer on: a. Sightings in general. b. How attention was drawn to object(s). (1) Sound, (2) Motion. (3) Glint of light. c. Degree of fatigue and duration of flight at time of sighting in cases where observer is airborne. 9. Witnesses. a. Addressees, b. Occupation. c. Reliability. 10. Comments of interrogator regarding the intelligence and character of person interrogated. Relative to Radar Sightings 1. Re radars operating on ground. a. Observations of range, speed, altitude and size of target. b. Did target executive any turns? If so, what angle (180°), etc. and what radius of turn. If radius of turn is not observable, how long did the target stay in the turn and what was its speed? c. Note particularly any separation of distant target into several targets upon approach. Track all if possible. 2, If airborne when object sighted. a, Were there any radar inductions or extra noise on radio circuits? b. Give estimates of size, speed, maneuvers, etc. GENERAL 1, Teletype sequences of local weather conditions. 2. Winds aloft report. -6- RESTRICTED

RESTRICTED 8. Local flight schedules of commercial, private and military aircraft flying in vicinity at the time. (Check Canadian activity if close to that border.) 4. Possible releases of testing devices in vicinity sent aloft by Ordnance, Navy, Air Force, Army, Weather Units, Research Organizations or any other. 5. If object contacted earth, obtain soil samples within and without depression or spot where object landed (and then presumably departed) for purpose of making comparison of soils. 6. If object came sufficiently near other aircraft or known objects check surfaces with Geiger counters for possible radioactivity. Make comparisons with other unaffected aircraft objects, etc. 7. Obtain photographs (or original negatives) where available; if not, secure sketches of: a. Object. b. Surrounding terrain where observed. c. Place where it contacted earth (if this happened). d, Maneuvers. e. Formation if objects were more than two. 8. Secure signed statement. 9. Obtain fragments or physical evidence where possible. 10. Was any radio antenna to be observed, i.e., (any projections or extentions that might presum- ably be construed as such). Cc. P, CABELL Major General, USAF Director of Intelligence, Office of Deputy Chief of Staff, Operations DISTRIBUTION: Commanding Generals, Major Air Commands, ZI and Overseas All United States Air Attaches Director of Central Intelligence Special Assistant for Research and Intelligence, Department of State Director of Intelligence, GSUSA Chief of Naval Intelligence Commandant (INT), United States Coast Guard Director, Federal Bureau of Investigation RESTRICTED -7-

RESTRICTED DEPARTMENT OF THE AIR FORCE HEADQUARTERS UNITED STATES AIR FORCE DIRECTORATE OF INTELLIGENCE WASHINGTON 25, D. C. 15 February 1949 AIR INTELLIGENCE REQUIREMENTS MEMORANDUM NUMBER 4 UNCONVENTIONAL AIRCRAFT PART I - GENERAL 1, PURPOSE The purpose of this memorandum is twofold: a. To enunciate continuing Air Force requirements for information pertaining to sightings of unconventional aircraft and unidentified flying objects, including the so-called ‘‘Flying Discs.” b. To establish procedures for reporting such information, 2. RESCISSION Department of the Army Collection Memorandum Number 7, dated 21 January 1948, and letter, CSGID 425.1, dated 25 March 1948, both subject as above, which have been transferred to Air Force agencies for action, are herewith superseded. 3. REPORTING a. General (1) As complete an answer to the requirements enunciated in Part II, as may be procur- able, should be dispatched by means of electrical transmission immediately after sightings. (2) Supplementary reports should be forwarded as available by the most expeditious means consistent with the importance of the information reported. (1) Initial and supplementary cabled reports will be transmitted to the Director of Intelli- gence, Headquarters United States Air Force. Cables will contain the phase, ‘‘Pass to COMGENAMC WRIGHT-PATTERSON AFB, DAYTON, OHIO, ATTN: MCIAXO-3.”” RESTRICTED ¢9-4892, AF

RESTRICTED (2) Supplementary written reports, prepared on AF Form 112, will be forwarded to the Director of Intelligence, Headquarters United States Air Force. (8) Commanding General, Air Materiel Command is authorized direct contact with major Air Commands (overseas) and organizations under their control in connection with the development of information on this subject. c. Major Air Commands (ZI) (1) Reports will be forwarded direct to the Commanding General, Air Materiel Command, Wright-Patterson Air Force Base, Dayton, Ohio, Attn: MCIAXO-3 by installations receiv- ing information pertaining to the requirements enunciated in Part II. (2) Copies of such reports may be supplied the Command Headquarters of the installation concerned, (8) A copy of all reports sent to Air Materiel Command in accordance with these instruc- tions will be forwarded at the same time to the Director of Intelligence, Headquarters United States Air Force. (4) Written reports will be submitted on AF Form 112. (5) Commanding General, Air Materiel Command is authorized direct contact with major Air Commands (ZI) and organizations under their control in connection with the develop- ment of information on this subject. d. Non-Air Force Agencies (1) Addressees other than those of the United States Air Force are requested to forward reports direct to the Commanding General, Air Materiel Command, Wright-Patterson Air Force Base, Dayton, Ohio, Attn: MCIAXO-3. (2) In order to reduce the time factor involved in transmission of this type of information it is requested that, wherever communications facilities permit, subordinate elements be authorized to communicate reports direct to the Commanding General, Air Materiel Com- mand, PART I - REQUIREMENTS General 1. Date of sighting. ‘ 2. Time of sighting (zonal by 24 hr. clock). 3. Where sighted (observer’s position): a. Ground (1) City, town. (2) Distance and direction from city or town, road, intersection, etc. (3) From building (story), yard, etc. (4) Map coordinates (if feasible) showing latitude and longitude. -2- RESTRICTED

RESTRICTED b, Air (1) Type aircraft, speed, altitude, direction of flight. (2) Distance and direction from city, town or known landmark. (8) Clock position of object from observer’s aircraft. (4) Latitude and longitude. c. Sea (1) Latitude and longitude. (2) Proximity to land. (Name city, country, etc.) 4, Number of objects, Formation type (if any), sketch if possible. 5. Observable celestial phenomena or planets that may account for the sighting. (Local facilities or organizations which follow such celestial phenomena should be consulted for such information.) 6. Distance of object from observer. a. Laterally or horizontally. b. Angle of elevation from horizon. c. Altitude. 7. Time in sight. 8, Appearance of object. a. Color. b. Shape. (Sketch if possible) c. Apparent construction. (Of what material or substance) d. Size, (1) Estimated size. (2) Size as it appeared from observer’s view. (Compared to known object) 9. Direction of flight. 10. Tactics or maneuvers. Vertical ascent or descent, horizontal, oscillating, fluttering, evasive, aggressive, erratic, etc. 11. Evidence of exhaust. a. Color of smoke. yb. Length and width. RESTRICTED -3-

RESTRICTED c. Odor (if any). d. Rate of evaporation. e. Does trail vary with sound? (spurts) 12, Effect on clouds. a. Opened path thru clouds. b. Forced cloud or mists, c. Reflected on cloud. 4, Showed thru cloud. { 13. Lights. a. Reflected or attached. b. Luminous ¢. Blinked on and off in relation to speed. 14, Support a. Wings. b. Aerodynamic list of fuselage. c. Vertical jet. d. Rotating cylinder or cone. e. Aerostatic lift (balloon or dirigible). 15. Propulsion. a. Propeller or jet. b. Rotor, c. Aerodynamic vanes (flapping or oscillating) (Katz Mayer effect). d. Visible exhaust or jet openings. 16. Control and stability. a. Fins b. Stabilizers (horizontal or vertical). (1) Size. (2) Shape. (3) Location. -4- RESTRICTED

RESTRICTED 17. Air ducts. a. Slots. b. Duct openings. 18. Speed - M.P.H. 19, Sound. a. Continuous whine or buzz. b. Roar, whistle, whoosh. c. Intermittent. 20, Manner of disappearance. a. Explode. (1) Possibility of fragments. (2) Other physical evidence. b. Faded from view. ce, Disappeared behind obstacle. Relative to the Observer 1, Name of observer. 2. Address. 3. Occupation. 4, Place of business. a. Employer or employee. 5. Pertinent hobbies, a. Is observer amateur astronomer, pilot, engineer, etc. b. Length of time engaged in hobby (experience). 6. Ability to determine: a. Color. b. Speed of moving objects. ce. Size at distance. 7. Reliability of observer. a. Sources. RESTRICTED -5-

RESTRICTED (1) Neighbors. (2) Police Dept. (3) FBI records. (4) Employer. f 8, Notes relative to observer on: a, Sightings in general. b. How attention was drawn to object(s). (1) Sound. (2) Motion. (3) Glint of light. c. Degree of fatigue and duration of flight at time of sighting in cases where observer is airborne, 9. Witnesses, a. Addressees. b. Occupation. c. Reliability. 10, Comments of interrogator regarding the intelligence and character of person interrogated. Relative to Radar Sightings 1. Re radars operating on ground. a. Observations of range, speed, altitude and size of target. b. Did target executive any turns? If so, what angle (180°), etc. and what radius of turn, If radius of turn is not observable, how long did the target stay in the turn and what was its speed? c. Note particularly any separation of distant target into several targets upon approach. Track all if possible. 2, If airborne when object sighted. a. Were there any radar inductions or extra noise on radio circuits? b. Give estimates of size, speed, maneuvers, etc. GENERAL 1. Teletype sequences of local weather conditions. 2. Winds aloft report. -6- RESTRICTED

RESTRICTED 8. Local flight schedules of commercial, private and military aircraft flying in vicinity at the time. (Check Canadian activity if close to that border.) 4. Possible releases of testing devices in vicinity sent aloft by Ordnance, Navy, Air Force, Army, Weather Units, Research Organizations or any other. 5. If object contacted earth, obtain soil samples within and without depression or spot where object landed (and then presumably departed) for purpose of making comparison of soils. 6. If object came sufficiently near other aircraft or known objects check surfaces with Geiger counters for possible radioactivity. Make comparisons with other unaffected aircraft objects, etc. 7. Obtain photographs (or original negatives) where available; if not, secure sketches of: a. Object. b. Surrounding terrain where observed. c. Place where it contacted earth (if this happened). d, Maneuvers, e. Formation if objects were more than two. 8, Secure signed statement. 9, Obtain fragments or physical evidence where possible. 10. Was any radio antenna to be observed, i.e., (any projections or extentions that might presum- ably be construed as such). Cc. P. CABELL Major General, USAF Director of Intelligence, Office of Deputy Chief of Staff, Operations DISTRIBUTION: Commanding Generals, Major Air Commands, ZI and Overseas All United States Air Attaches Director of Central Intelligence Special Assistant for Research and Intelligence, Department of State Director of Intelligence, GSUSA Chief of Naval Intelligence Commandant (INT), United States Coast Guard Director, Federal Bureau of Investigation RESTRICTED -7-

RESTRICTED : DEPARTMENT OF THE AIR FORCE HEADQUARTERS UNITED STATES AIR FORCE DIRECTORATE OF INTELLIGENCE WASHINGTON 25, D. C. 15 February 1949 AIR INTELLIGENCE REQUIREMENTS MEMORANDUM NUMBER 4 UNCONVENTIONAL AIRCRAFT PART I - GENERAL 1. PURPOSE The purpose of this memorandum is twofold: a. To enunciate continuing Air Force requirements for information pertaining to sightings of unconventional aircraft and unidentified flying objects, including the so-called ‘Flying Discs.” b. To establish procedures for reporting such information. 2. RESCISSION Department of the Army Collection Memorandum Number 7, dated 21 January 1948, and letter, CSGID 425.1, dated 25 March 1948, both subject as above, which have been transferred to Air Force agencies for action, are herewith superseded. 3. REPORTING a. General (1) As complete an answer to the requirements enunciated in Part II, as may be procur- able, should be dispatched by means of electrical transmission immediately after sightings. (2) Supplementary reports should be forwarded as available by the most expeditious means consistent with the importance of the information reported. b. Major Air Commands (Overseas) and Air Attaches (1) Initial and supplementary cabled reports will be transmitted to the Director of Intelli- gence, Headquarters United States Air Force, Cables will contain the phase, ‘Pass to COMGENAMC WRIGHT-PATTERSON AFB, DAYTON, OHIO, ATTN: MCIAXO-3.”’ RESTRICTED 9-892, AF

RESTRICTED (2) Supplementary written reports, prepared on AF Form 112, will be forwarded to the Director of Intelligence, Headquarters United States Air Force. (8) Commanding General, Air Materiel Command is authorized direct contact with major Air Commands (overseas) and organizations under their control in connection with the development of information on this subject. ¢. Major Air Commands (ZI) (1) Reports will be forwarded direct to the Commanding General, Air Materiel Command, Wright-Patterson Air Force Base, Dayton, Ohio, Attn: MCIAXO-3 by installations receiv- ing information pertaining to the requirements enunciated in Part II. (2) Copies of such reports may be supplied the Command Headquarters of the installation concerned, (8) A copy of all reports sent to Air Materiel Command in accordance with these instruc- tions will be forwarded at the same time to the Director of Intelligence, Headquarters United States Air Force. (4) Written reports will be submitted on AF Form 112, (5) Commanding General, Air Materiel Command is authorized direct contact with major Air Commands (ZI) and organizations under their control in connection with the develop- ment of information on this subject. d. Non-Air Force Agencies (1) Addressees other than those of the United States Air Force are requested to forward reports direct to the Commanding General, Air Materiel Command, Wright-Patterson Air Force Base, Dayton, Ohio, Attn: MCIAXO-3, (2) In order to reduce the time factor involved in transmission of this type of information it is requested that, wherever communications facilities permit, subordinate elements be authorized to communicate reports direct to the Commanding General, Air Materiel Com- mand, PART I. - REQUIREMENTS General 1. Date of sighting. 2. Time of sighting (zonal by 24 hr. clock). 8. Where sighted (observer’s position): a. Ground (1) City, town. (2) Distance and direction from city or town, road, intersection, etc. (8) From building (story), yard, etc. (4) Map coordinates (if feasible) showing latitude and longitude. -2- RESTRICTED

RESTRICTED b. Air (1) Type aircraft, speed, altitude, direction of flight. (2) Distance and direction from city, town or known landmark, (3) Clock position of object from observer’s aircraft. (4) Latitude and longitude. (1) Latitude and longitude. (2) Proximity to land. (Name city, country, etc.) 4, Number of objects. Formation type (if any), sketch if possible. 5. Observable celestial phenomena or planets that may account for the sighting. (Local facilities or organizations which follow such celestial phenomena should be consulted for such information.) 6. Distance of object from observer. a. Laterally or horizontally. b. Angle of elevation from horizon, c. Altitude. 7. Time in sight. 8, Appearance of object. a. Color, b. Shape. (Sketch if possible) c. Apparent construction. (Of what material or substance) d. Size. (1) Estimated size. (2) Size as it appeared from observer’s view. (Compared to known object) 9, Direction of flight. 10. Tactics or maneuvers. Vertical ascent or descent, horizontal, oscillating, fluttering, evasive, aggressive, erratic, etc. 11, Evidence of exhaust. a. Color of smoke. yb. Length and width, RESTRICTED -3-

RESTRICTED c. Odor (if any). d. Rate of evaporation. e. Does trail vary with sound? (spurts) 12, Effect on clouds. a. Opened path thru clouds. b. Forced cloud or mists. c. Reflected on cloud. d, Showed thru cloud. 13, Lights. a, Reflected or attached. b, Luminous c. Blinked on and off in relation to speed. 14, Support a, Wings. b. Aerodynamic list of fuselage. ce. Vertical jet. d. Rotating cylinder or cone. “ e. Aerostatic lift (balloon or dirigible). 15. Propulsion, a. Propeller or jet. b. Rotor. c, Aerodynamic vanes (flapping or oscillating) (Katz Mayer effect). d. Visible exhaust or jet openings. 16. Control and stability. a. Fins b. Stabilizers (horizontal or vertical). (1) Size. (2) Shape. (8) Location. -4- RESTRICTED

RESTRICTED 17. Air ducts. a. Slots. b. Duct openings. 18. Speed - M.P.H. 19, Sound. a. Continuous whine or buzz. b. Roar, whistle, whoosh, c. Intermittent. 20. Manner of disappearance. a. Explode. (1) Possibility of fragments. (2) Other physical evidence. b. Faded from view. c. Disappeared behind obstacle. Relative to the Observer 1. Name of observer. 2. Address, 3. Occupation. 4, Place of business. a. Employer or employee. 5. Pertinent hobbies. a. Is observer amateur astronomer, pilot, engineer, etc. b. Length of time engaged in hobby (experience). 6, Ability to determine: a. Color. b. Speed of moving objects. c. Size at distance. 7. Reliability of observer. a. Sources. RESTRICTED -5-

RESTRICTED (1) Neighbors. (2) Police Dept. (8) FBI records. (4) Employer. 8. Notes relative to observer on: a. Sightings in general. b. How attention was drawn to object(s). (1) Sound, (2) Motion. (8) Glint of light. c. Degree of fatigue and duration of flight at time of sighting in cases where observer is airborne. 9. Witnesses. a, Addressees, b. Occupation. c. Reliability. 10. Comments of interrogator regarding the intelligence and character of person interrogated. Relative to Radar Sightings 1, Re radars operating on ground. a. Observations of range, speed, altitude and size of target. b, Did target executive any turns? If so, what angle (180°), etc. and what radius of turn. If radius of turn is not observable, how long did the target stay in the turn and what was its speed? c, Note particularly any separation of distant target into several targets upon approach. Track all if possible. 2. If airborne when object sighted. a. Were there any radar inductions or extra noise on radio circuits? b. Give estimates of size, speed, maneuvers, etc. GENERAL 1. Teletype sequences of local weather conditions. 2. Winds aloft report. -6- RESTRICTED

RESTRICTED 8. Local flight schedules of commercial, private and military aircraft flying in vicinity at the time. (Check Canadian activity if close to that border.) 4, Possible releases of testing devices in vicinity sent aloft by Ordnance, Navy, Air Force, Army, Weather Units, Research Organizations or any other. 5. If object contacted earth, obtain soil samples within and without depression or spot where object landed (and then presumably departed) for purpose of making comparison of soils. 6. If object came sufficiently near other aircraft or known objects check surfaces with Geiger counters for possible radioactivity. Make comparisons with other unaffected aircraft objects, etc. 7. Obtain photographs (or original negatives) where available; if not, secure sketches of: a. Object. b. Surrounding terrain where observed. c, Place where it contacted earth (if this happened). d, Maneuvers. e. Formation if objects were more than two. 8. Secure signed statement, 9. Obtain fragments or physical evidence where possible. 10. Was any radio antenna to be observed, {.e., (any projections or extentions that might presum- ably be construed as such). Cc. P. CABELL Major General, USAF Director of Intelligence, Office of Deputy Chief of Staff, Operations DISTRIBUTION: Commanding Generals, Major Air Commands, ZI and Overseas All United States Air Attaches Director of Central Intelligence Special Assistant for Research and Intelligence, Department of State Director of Intelligence, GSUSA Chief of Naval Intelligence Commandant (INT), United States Coast Guard Director, Federal Bureau of Investigation RESTRICTED -7-

RESTRICTED DEPARTMENT OF THE AIR FORCE HEADQUARTERS UNITED STATES AIR FORCE DIRECTORATE OF INTELLIGENCE WASHINGTON 25, D. C. 15 February 1949 AIR INTELLIGENCE REQUIREMENTS MEMORANDUM NUMBER 4 UNCONVENTIONAL AIRCRAFT PART I - GENERAL 1, PURPOSE The purpose of this memorandum is twofold: a. To enunciate continuing Air Force requirements for information pertaining to sightings of unconventional aircraft and unidentified flying objects, including the so-called ‘Flying Discs.” b. To establish procedures for reporting such information. 2. RESCISSION Department of the Army Collection Memorandum Number 7, dated 21 January 1948, and letter, CSGID 425.1, dated 25 March 1948, both subject as above, which have been transferred to Air Force agencies for action, are herewith superseded. 8. REPORTING a, General (1) As complete an answer to the requirements enunciated in Part Il, as may be procur- able, should be dispatched by means of electrical transmission immediately after sightings. (2) Supplementary reports should be forwarded as available by the most expeditious means consistent with the importance of the information reported. b. Major Air Commands (Overseas) and Air Attaches (1) Initial and supplementary cabled reports will be transmitted to the Director of Intelli- gence, Headquarters United States Air Force. Cables will contain the phase, “Pass to COMGENAMC WRIGHT-PATTERSON AFB, DAYTON, OHIO, ATTN: MCIAXO-3.’’ RESTRICTED 9-4892, AF

RESTRICTED (2) Supplementary written reports, prepared on AF Form 112, will be forwarded to the Director of Intelligence, Headquarters United States Air Force. (3) Commanding General, Air Materiel Command is authorized direct contact with major Air Commands (overseas) and organizations under their control in connection with the development of information on this subject. ¢. Major Air Commands (ZI) (1) Reports will be forwarded direct to the Commanding General, Air Materiel Command, Wright-Patterson Air Force Base, Dayton, Ohio, Attn: MCIAXO-3 by installations receiv- ing information pertaining to the requirements enunciated in Part II. (2) Copies of such reports may be supplied the Command Headquarters of the installation concerned, (8) A copy of all reports sent to Air Materiel Command in accordance with these instruc- tions will be forwarded at the same time to the Director of Intelligence, Headquarters United States Air Force, (4) Written reports will be submitted on AF Form 112. (5) Commanding General, Air Materiel Command is authorized direct contact with major Air Commands (ZI) and organizations under their control in connection with the develop- ment of information on this subject. d. Non-Air Force Agencies (1) Addressees other than those of the United States Air Force are requested to forward reports direct to the Commanding General, Air Materiel Command, Wright-Patterson Air Force Base, Dayton, Ohio, Attn: MCIAXO-3. (2) In order to reduce the time factor involved in transmission of this type of information it is requested that, wherever communications facilities permit, subordinate elements be authorized to communicate reports direct to the Commanding General, Air Materiel Com- mand. PART Il - REQUIREMENTS General 1. Date of sighting. , 2, Time of sighting (zonal by 24 hr. clock). 8. Where sighted (observer’s position): a. Ground (1) City, town. (2) Distance and direction from city or town, road, intersection, etc. (3) From building (story), yard, etc. (4) Map coordinates (if feasible) showing latitude and longitude. -2- RESTRICTED

RESTRICTED b, Air (1) ‘Type aircraft, speed, altitude, direction of flight. (2) Distance and direction from city, town or known landmark, (8) Clock position of object from observer’s aircraft. (4) Latitude and longitude. c, Sea (1) Latitude and longitude. (2) Proximity to land. (Name city, country, etc.) 4, Number of objects. Formation type (if any), sketch if possible. 5. Observable celestial phenomena or planets that may account for the sighting. (Local facilities or organizations which follow such celestial phenomena should be consulted for such information.) 6. Distance of object from observer. a. Laterally or horizontally. b. Angle of elevation from horizon. c. Altitude. 7. Time in sight. 8, Appearance of object. a. Color. b. Shape. (Sketch if possible) c. Apparent construction. (Of what material or substance) d. Size. (1) Estimated size. (2) Size as it appeared from observer’s view. (Compared to known object) 9. Direction of flight. 10. Tactics or maneuvers, Vertical ascent or descent, horizontal, oscillating, fluttering, evasive, aggressive, erratic, etc. 11. Evidence of exhaust. a. Color of smoke, yb, Length and width. RESTRICTED -3-

RESTRICTED ¢. Odor (if any). d. Rate of evaporation. e. Does trail vary with sound? (spurts) 12, Effect on clouds. a. Opened path thru clouds. b. Forced cloud or mists. c. Reflected on cloud. d. Showed thru cloud. 13, Lights. a. Reflected or attached. b. Luminous ¢. Blinked on and off in relation to speed. 14, Support a. Wings. b. Aerodynamic list of fuselage. c. Vertical jet. d. Rotating cylinder or cone. e. Aerostatic lift (balloon or dirigible). 15. Propulsion. a. Propeller or jet. b. Rotor. c. Aerodynamic vanes (flapping or oscillating) (Katz Mayer effect). da. Visible exhaust or jet openings. 16. Control ard stability. a. Fins b. Stabilizers (horizontal or vertical). (1) Size. (2) Shape. (3) Location. -4- RESTRICTED

RESTRICTED 17. Air ducts. a. Slots. b. Duct openings. 18. Speed - M.P.H. 19. Sound. a. Continuous whine or buzz. b. Roar, whistle, whoosh. c. Intermittent. 20. Manner of disappearance. a. Explode. (1) Possibility of fragments. (2) Other physical evidence, b, Faded from view. ce, Disappeared behind obstacle. Relative to the Observer 1. Name of observer. 2, Address, 3. Occupation. 4, Place of business. a. Employer or employee. 5. Pertinent hobbies. a. Is observer amateur astronomer, pilot, engineer, etc. b. Length of time engaged in hobby (experience). 6. Ability to determine: a. Color. b. Speed of moving objects. c. Size at distance. 7. Reliability of observer. a. Sources. RESTRICTED a5.

RESTRICTED (1) Neighbors. (2) Police Dept. (3) FBI records. (4) Employer. Z 8, Notes relative to observer on: a, Sightings in general. b. How attention was drawn to object(s). (1) Sound, (2) Motion, (3) Glint of light. ce, Degree of fatigue and duration of flight at time of sighting in cases where observer is airborne. 9. Witnesses. a. Addressees, b. Occupation. ce. Reliability. 10. Comments of interrogator regarding the intelligence and character of person interrogated. Relative to Radar Sightings 1, Re radars operating on ground. a. Observations of range, speed, altitude and size of target. b. Did target executive any turns? If so, what angle (180°), etc. and what radius of turn. If radius of turn is not observable, how long did the target stay in the turn and what was its speed? c. Note particularly any separation of distant target into several targets upon approach. Track all if possible. 2. If airborne when object sighted. a, Were there any radar inductions or extra noise on radio circuits? b. Give estimates of size, speed, maneuvers, etc. GENERAL 1. Teletype sequences of local weather conditions. 2. Winds aloft report. -6- RESTRICTED

RESTRICTED 3. Local flight schedules of commercial, private and military aircraft flying in vicinity at the time. (Check Canadian activity if close to that border.) 4. Possible releases of testing devices in vicinity sent aloft by Ordnance, Navy, Air Force, Army, Weather Units, Research Organizations or any other. 5. If object contacted earth, obtain soil samples within and without depression or spot where object landed (and then presumably departed) for purpose of making comparison of soils. 6. If object came sufficiently near other aircraft or known objects check surfaces with Geiger counters for possible radioactivity. Make comparisons with other unaffected aircraft objects, etc. 7. Obtain photographs (or original negatives) where available; if not, secure sketches of: a. Object. b. Surrounding terrain where observed. ce. Place where it contacted earth (if this happened). d. Maneuvers. e. Formation if objects were more than two. 8, Secure signed statement. 9, Obtain fragments or physical evidence where possible. 10. Was any radio antenna to be observed, i.e., (any projections or extentions that might presum- ably be construed as such). C. P. CABELL Major General, USAF Director of Intelligence, Office of Deputy Chief of Staff, Operations DISTRIBUTION: Commanding Generals, Major Air Commands, ZI and Overseas All United States Air Attaches Director of Central Intelligence Special Assistant for Research and Intelligence, Department of State Director of Intelligence, GSUSA Chief of Naval Intelligence Commandant (INT), United States Coast Guard Director, Federal Bureau of Investigation RESTRICTED -7-

RESTRICTED ; DEPARTMENT OF THE AIR FORCE HEADQUARTERS UNITED STATES AIR FORCE DIRECTORATE OF INTELLIGENCE WASHINGTON 25, D. C. 15 February 1949 AIR INTELLIGENCE REQUIREMENTS MEMORANDUM NUMBER 4 UNCONVENTIONAL AIRCRAFT PART I - GENERAL 1. PURPOSE The purpose of this memorandum is twofold: a. To enunciate continuing Air Force requirements for information pertaining to sightings of unconventional aircraft and unidentified flying objects, including the so-called ‘‘Flying Discs.” b. To establish procedures for reporting such information. 2. RESCISSION Department of the Army Collection Memorandum Number 7, dated 21 January 1948, and letter, CSGID 425.1, dated 25 March 1948, both subject as above, which have been transferred to Air Force agencies for action, are herewith superseded. 8. REPORTING a. General (1) As complete an answer to the requirements enunciated in Part Il, as may be procur- able, should be dispatched by means of electrical transmission immediately after sightings, (2) Supplementary reports should be forwarded as available by the most expeditious means consistent with the importance of the information reported. b. Major Air Commands (Overseas) and Air Attaches (1) Initial and supplementary cabled reports will be transmitted to the Director of Intelli- gence, Headquarters United States Air Force. Cables will contain the phase, ‘Pass to COMGENAMC WRIGHT-PATTERSON AFB, DAYTON, OHIO, ATTN: MCIAXO-3.” RESTRICTED ¢9-4892, AF

RESTRICTED (2) Supplementary written reports, prepared on AF Form 112, will be forwarded to the Director of Intelligence, Headquarters United States Air Force. (8) Commanding General, Air Materiel Command is authorized direct contact with major Air Commands (overseas) and organizations under their control in connection with the development of information on this subject. c. Major Air Commands (ZI) (1) Reports will be forwarded direct to the Commanding General, Air Materiel Command, Wright-Patterson Air Force Base, Dayton, Ohio, Attn: MCIAXO-3 by installations receiv- ing information pertaining to the requirements enunciated in Part II. (2) Copies of such reports may be supplied the Command Headquarters of the installation concerned, (8) A copy of all reports sent to Air Materiel Command in accordance with these instruc- tions will be forwarded at the same time to the Director of Intelligence, Headquarters United States Air Force. (4) Written reports will be submitted on AF Form 112. (5) Commanding General, Air Materiel Command is authorized direct contact with major Air Commands (ZI) and organizations under their control in connection with the develop- ment of information on this subject. d, Non-Air Force Agencies (1) Addressees other than those of the United States Air Force are requested to forward reports direct to the Commanding General, Air Materiel Command, Wright-Patterson Air Force Base, Dayton, Ohio, Attn: MCIAXO-3, (2) In order to reduce the time factor involved in transmission of this type of information it is requested that, wherever communications facilities permit, subordinate elements be authorized to communicate reports direct to the Commanding General, Air Materiel Com- mand, PART II - REQUIREMENTS General 1. Date of sighting. 2. Time of sighting (zonal by 24 hr. clock), 8. Where sighted (observer’s position): a. Ground (1) City, town, (2) Distance and direction from city or town, road, intersection, etc. (8) From building (story), yard, etc. (4) Map coordinates (if feasible) showing latitude and longitude. a2 RESTRICTED

RESTRICTED b. Air (1) Type aircraft, speed, altitude, direction of flight. (2) Distance and direction from city, town or known landmark. (3) Clock position of object from observer’s aircraft. (4) Latitude and longitude. (1) Latitude and longitude. (2) Proximity to land. (Name city, country, etc.) 4, Number of objects. Formation type (if any), sketch if possible. 5. Observable celestial phenomena or planets that may account for the sighting. (Local facilities or organizations which follow such celestial phenomena should be consulted for such information.) 6. Distance of object from observer. a. Laterally or horizontally. b. Angle of elevation from horizon. c. Altitude. 7. Time in sight. 8. Appearance of object. a. Color. b. Shape. (Sketch if possible) c. Apparent construction. (Of what material or substance) d. Size. (1) Estimated size. (2) Size as it appeared from observer’s view. (Compared to known object) 9, Direction of flight. 10, Tactics or maneuvers. Vertical ascent or descent, horizontal, oscillating, fluttering, evasive, aggressive, erratic, etc. 11, Evidence of exhaust. a. Color of smoke, ‘b. Length and width. RESTRICTED -3-

RESTRICTED c. Odor (if any). d. Rate of evaporation. e. Does trail vary with sound? (spurts) 12, Effect on clouds, a. Opened path thru clouds. b. Forced cloud or mists. c. Reflected on cloud. d, Showed thru cloud. 18, Lights. a. Reflected or attached. b. Luminous ¢, Blinked on and off in relation to speed. 14. Support a, Wings. b, Aerodynamic list of fuselage. c. Vertical jet. d, Rotating cylinder or cone. “ e. Aerostatic lift (balloon or dirigible). 15. Propulsion. a. Propeller or jet. b, Rotor. c. Aerodynamic vanes (flapping or oscillating) (Katz Mayer effect). d. Visible exhaust or jet openings. 16, Control and stability. a, Fins b. Stabilizers (horizontal or vertical). (1) Size. (2) Shape. (8) Location. -4- RESTRICTED

RESTRICTED 17, Air ducts. a. Slots. b. Duct openings. 18. Speed - M.P.H. 19. Sound, a, Continuous whine or buzz. b. Roar, whistle, whoosh. c. Intermittent. 20. Manner of disappearance. a. Explode. (1) Possibility of fragments. (2) Other physical evidence. b. Faded from view. c. Disappeared behind obstacle. Relative to the Observer 1, Name of observer. 2. Address. 3, Occupation. 4. Place of business, a. Employer or employee. 5. Pertinent hobbies. a. Is observer amateur astronomer, pilot, engineer, etc. b. Length of time engaged in hobby (experience), 6, Ability to determine: a. Color. b. Speed of moving objects. c. Size at distance. 7. Reliability of observer. a. Sources. RESTRICTED ee

RESTRICTED (1) Neighbors. (2) Police Dept. (3) FBI records. (4) Employer. 8. Notes relative to observer on: a. Sightings in general. b. How attention was drawn to object(s). (1) Sound. (2) Motion. (83) Glint of light. c, Degree of fatigue and duration of flight at time of sighting in cases where observer is airborne, 9. Witnesses, a. Addressees, b. Occupation. c. Reliability. 10. Comments of interrogator regarding the intelligence and character of person interrogated. Relative to Radar Sightings 1. Re radars operating on ground. a, Observations of range, speed, altitude and size of target. b. Did target executive any turns? If so, what arigle (180°), etc. and what radius of turn, If radius of turn is not observable, how long did the target stay in the turn and what was its speed? c. Note particularly any separation of distant target into several targets upon approach. Track all if possible. 2, If airborne when object sighted. a. Were there any radar inductions or extra noise on radio circuits? b. Give estimates of size, speed, maneuvers, etc. GENERAL 1. Teletype sequences of local weather conditions. 2, Winds aloft report. -6- RESTRICTED

RESTRICTED 8. Local flight schedules of commercial, private and military aircraft flying in vicinity at the time. (Check Canadian activity if close to that border.) 4, Possible releases of testing devices in vicinity sent aloft by Ordnance, Navy, Air Force, Army, Weather Units, Research Organizations or any other. 5. If object contacted earth, obtain soil samples within and without depression or spot where object landed (and then presumably departed) for purpose of making comparison of soils. 6. If object came sufficiently near other aircraft or known objects check surfaces with Geiger counters for possible radioactivity. Make comparisons with other unaffected aircraft objects, etc. 7. Obtain photographs (or original negatives) where available; if not, secure sketches of: a. Object. b, Surrounding terrain where observed. c. Place where it contacted earth (if this happened). d, Maneuvers. e. Formation if objects were more than two. 8, Secure signed statement. 9. Obtain fragments or physical evidence where possible. 10. Was any radio antenna to be observed, i.e., (any projections or extentions that might presum- ably be construed as such). Cc. P, CABELL Major General, USAF Director of Intelligence, Office of Deputy Chief of Staff, Operations DISTRIBUTION: Commanding Generals, Major Air Commands, ZI and Overseas All United States Air Attaches Director of Central Intelligence Special Assistant for Research and Intelligence, Department of State Director of Intelligence, GSUSA Chief of Naval Intelligence Commandant (INT), United States Coast Guard Director, Federal Bureau of Investigation RESTRICTED -7-

RESTRICTED DEPARTMENT OF THE AIR FORCE HEADQUARTERS UNITED STATES AIR FORCE DIRECTORATE OF INTELLIGENCE WASHINGTON 25, D. C. 15 February 1949 AIR INTELLIGENCE REQUIREMENTS MEMORANDUM NUMBER 4 UNCONVENTIONAL AIRCRAFT PART I - GENERAL 1. PURPOSE The purpose of this memorandum is twofold: a. To enunciate continuing Air Force requirements for information pertaining to sightings of unconventional aircraft and unidentified flying objects, including the so-called ‘‘Flying Discs.” b. To establish procedures for reporting such information. 2. RESCISSION Department of the Army Collection Memorandum Number 7, dated 21 January 1948, and letter, CSGID 425.1, dated 25 March 1948, both subject as above, which have been transferred to Air Force agencies for action, are herewith superseded. 3, REPORTING a. General (1) As complete an answer to the requirements enunciated in Part Il, as may be procur- able, should be dispatched by means of electrical transmission immediately after sightings. (2) Supplementary reports should be forwarded as available by the most expeditious means consistent with the importance of the information reported. b. Major Air Commands (Overseas) and Air Attaches (1) Initial and supplementary cabled reports will be transmitted to the Director of Intelli- gence, Headquarters United States Air Force. Cables will contain the phase, ‘‘Pass to COMGENAMC WRIGHT-PATTERSON AFB, DAYTON, OHIO, ATTN: MCIAXO-3.” RESTRICTED 69-4892, AF

RESTRICTED (2) Supplementary written reports, prepared on AF Form 112, will be forwarded to the - Director of Intelligence, Headquarters United States Air Force, (3) Commanding General, Air Materiel Command is authorized direct contact with major Air Commands (overseas) and organizations under their control in connection with the development of information on this subject. ¢. Major Air Commands (ZI) (1) Reports will be forwarded direct to the Commanding General, Air Materiel Command, Wright-Patterson Air Force Base, Dayton, Ohio, Attn: MCIAXO-3 by installations receiv- ing information pertaining to the requirements enunciated in Part II. (2) Copies of such reports may be supplied the Command Headquarters of the installation concerned, (3) A copy of all reports sent to Air Materiel Command in accordance with these instruc- tions will be forwarded at the same time to the Director of Intelligence, Headquarters United States Air Force. (4) Written reports will be submitted on AF Form 112. (5) Commanding General, Air Materiel Command is authorized direct contact with major Air Commands (ZI) and organizations under their control in connection with the develop- ment of information on this subject. d. Non-Air Force Agencies (1) Addressees other than those of the United States Air Force are requested to forward reports direct to the Commanding General, Air Materiel Command, Wright-Patterson Air Force Base, Dayton, Ohio, Attn: MCIAXO-3. (2) In order to reduce the time factor involved in transmission of this type of information it is requested that, wherever communications facilities permit, subordinate elements be authorized to communicate reports direct to the Commanding General, Air Materiel Com- mand. PART II - REQUIREMENTS General 1, Date of sighting. ¥ 2, Time of sighting (zonal by 24 hr. clock). 3. Where sighted (observer’s position): a. Ground (1) City, town. (2) Distance and direction from city or town, road, intersection, etc. (3) From building (story), yard, etc. (4) Map coordinates (if feasible) showing latitude and longitude. -2- RESTRICTED

RESTRICTED >, Air (1) Type aircraft, speed, altitude, direction of flight. (2) Distance and direction from city, town or known landmark. (8) Clock position of object from observer’s aircraft. (4) Latitude and longitude. (1) Latitude and longitude. (2) Proximity to land. (Name city, country, etc.) 4, Number of objects. Formation type (if any), sketch if possible. 5. Observable celestial phenomena or planets that may account for the sighting. (Local facilities or organizations which follow such celestial phenomena should be consulted for such information.) 6. Distance of object from observer. a. Laterally or horizontally. b. Angle of elevation from horizon. c. Altitude. 7. Time in sight. 8. Appearance of object. a, Color. b. Shape. (Sketch if possible) ce. Apparent construction. (Of what material or substance) d. Size. (1) Estimated size. (2) Size as it appeared from observer’s view. (Compared to known object) 9. Direction of flight. 10. Tactics or maneuvers. Vertical ascent or descent, horizontal, oscillating, fluttering, evasive, aggressive, erratic, etc. 11, Evidence of exhaust. a. Color of smoke. yb. Length and width. RESTRICTED -'3~.

RESTRICTED ce, Odor (if any). d. Rate of evaporation. e. Does trail vary with sound? (spurts) 12. Effect on clouds, a. Opened path thru clouds. b. Forced cloud or mists. c. Reflected on cloud. d. Showed thru cloud. | 13. Lights. a. Reflected or attached. b. Luminous c. Blinked on and off in relation to speed. 14, Support a. Wings. b. Aerodynamic list of fuselage. ec. Vertical jet. d. Rotating cylinder or cone. e. Aerostatic lift (balloon or dirigible). 15. Propulsion. a. Propeller or jet. b. Rotor. c. Aerodynamic vanes (flapping or oscillating) (Katz Mayer effect). d. Visible exhaust or jet openings. 16, Control and stability. a. Fins b. Stabilizers (horizontal or vertical). (1) Size. (2) Shape, (3) Location. cA RESTRICTED

RESTRICTED 17. Air ducts. a. Slots. b. Duct openings. 18. Speed - M.P.H. 19. Sound. a. Continuous whine or buzz. b. Roar, whistle, whoosh. c. Intermittent. 20. Manner of disappearance. a. Explode. (1) Possibility of fragments. (2) Other physical evidence. b, Faded from view, c. Disappeared behind obstacle. Relative to the Observer 1, Name of observer. 2, Address. 3. Occupation. 4, Place of business. a. Employer or employee. 5. Pertinent hobbies, a. Is observer amateur astronomer, pilot, engineer, etc. b. Length of time engaged in hobby (experience). 6. Ability to determine: a. Color. b. Speed of moving objects. c. Size at distance, 7. Reliability of observer. a. Sources. RESTRICTED -5-

RESTRICTED (1) Neighbors. (2) Police Dept. (3) FBI records. (4) Employer. A 8. Notes relative to observer on: a. Sightings in general. b. How attention was drawn to object(s). (1) Sound. (2) Motion, (3) Glint of light. c. Degree of fatigue and duration of flight at time of sighting in cases where observer is airborne. 9, Witnesses, a. Addressees. b. Occupation, c. Reliability. 10. Comments of interrogator regarding the intelligence and character of person interrogated. Relative to Radar Sightings 1. Re radars operating on ground. a. Observations of range, speed, altitude and size of target. b. Did target executive any turns? If so, what angle (180°), etc. and what radius of turn. If radius of turn is not observable, how long did the target stay in the turn and what was its speed? c. Note particularly any separation of distant target into several targets upon approach. Track all if possible. 2. If airborne when object sighted. a. Were there any radar inductions or extra noise on radio circuits? b. Give estimates of size, speed, maneuvers, etc. GENERAL 1. Teletype sequences of local weather conditions. 2. Winds aloft report. -6- RESTRICTED

RESTRICTED 3. Local flight schedules of commercial, private and military aircraft flying in vicinity at the time. (Check Canadian activity if close to that border.) 4. Possible releases of testing devices in vicinity sent aloft by Ordnance, Navy, Air Force, Army, Weather Units, Research Organizations or any other. 5. If object contacted earth, obtain soil samples within and without depression or spot where object landed (and then presumably departed) for purpose of making comparison of soils. 6. If object came sufficiently near other aircraft or known objects check surfaces with Geiger counters for possible radioactivity. Make comparisons with other unaffected aircraft objects, etc. 7. Obtain photographs (or original negatives) where available; if not, secure sketches of: a. Object. b. Surrounding terrain where observed. c. Place where it contacted earth (if this happened). d, Maneuvers, e. Formation if objects were more than two. 8, Secure signed statement. 9, Obtain fragments or physical evidence where possible. 10. Was any radio antenna to be observed, i.e., (any projections or extentions that might presum- ably be construed as such). C. P. CABELL Major General, USAF Director of Intelligence, Office of Deputy Chief of Staff, Operations DISTRIBUTION: Commanding Generals, Major Air Commands, ZI and Overseas All United States Air Attaches Director of Central Intelligence Special Assistant for Research and Intelligence, Department of State Director of Intelligence, GSUSA Chief of Naval Intelligence Commandant (INT), United States Coast Guard Director, Federal Bureau of Investigation RESTRICTED -7-

RESTRICTED i DEPARTMENT OF THE AIR FORCE HEADQUARTERS UNITED STATES AIR FORCE DIRECTORATE OF INTELLIGENCE WASHINGTON 25, D. C. 15 February 1949 AIR INTELLIGENCE REQUIREMENTS MEMORANDUM NUMBER 4 UNCONVENTIONAL AIRCRAFT PART I - GENERAL 1. PURPOSE The purpose of this memorandum is twofold: a. To enunciate continuing Air Force requirements for information pertaining to sightings of unconventional aircraft and unidentified flying objects, including the so-called “Flying Discs.” b. To establish procedures for reporting such information. 2. RESCISSION Department of the Army Collection Memorandum Number 7, dated 21 January 1948, and letter, CSGID 425.1, dated 25 March 1948, both subject as above, which have been transferred to Air Force agencies for action, are herewith superseded. 8. REPORTING a. General (1) As complete an answer to the requirements enunciated in Part II, as may be procur- able, should be dispatched by means of electrical transmission immediately after sightings. (2) Supplementary reports should be forwarded as available by the most expeditious means consistent with the importance of the information reported. b. Major Air Commands (Overseas) and Air Attaches (1) Initial and supplementary cabled reports will be transmitted to the Director of Intelli- gence, Headquarters United States Air Force. Cables will contain the phase, “Pass to COMGENAMC WRIGHT-PATTERSON AFB, DAYTON, OHIO, ATTN: MCIAXO-3.’’ RESTRICTED ¢9-4892, AF

RESTRICTED (2) Supplementary written reports, prepared on AF Form 112, will be forwarded to the Director of Intelligence, Headquarters United States Air Force, (3) Commanding General, Air Materiel Command is authorized direct contact with major Air Commands (overseas) and organizations under their control in connection with the development of information on this subject. c. Major Air Commands (ZI) (1) Reports will be forwarded direct to the Commanding General, Air Materiel Command, Wright-Patterson Air Force Base, Dayton, Ohio, Attn: MCIAXO-3 by installations receiv- ing information pertaining to the requirements enunciated in Part II. (2) Copies of such reports may be supplied the Command Headquarters of the installation concerned, (3) A copy of all reports sent to Air Materiel Command in accordance with these instruc- tions will be forwarded at the same time to the Director of Intelligence, Headquarters United States Air Force, (4) Written reports will be submitted on AF Form 112. (5) Commanding General, Air Materiel Command is authorized direct contact with major Air Commands (ZI) and organizations under their control in connection with the develop- ment of information on this subject. d. Non-Air Force Agencies (1) Addressees other than those of the United States Air Force are requested to forward reports direct to the Commanding General, Air Materiel Command, Wright-Patterson Air Force Base, Dayton, Ohio, Attn: MCIAXO-3. (2) In order to reduce the time factor involved in transmission of this type of information it is requested that, wherever communications facilities permit, subordinate elements be authorized to communicate reports direct to the Commanding General, Air Materiel Com- mand, PART I. - REQUIREMENTS General 1, Date of sighting. 2. Time of sighting (zonal by 24 hr. clock). 3. Where sighted (observer’s position): a, Ground (1) City, town. (2) Distance and direction from city or town, road, intersection, etc. (3) From building (story), yard, etc. (4) Map coordinates (if feasible) showing latitude and longitude. -2- RESTRICTED

RESTRICTED b. Air (1) Type aircraft, speed, altitude, direction of flight. (2) Distance and direction from city, town or known landmark. (8) Clock position of object from observer’s aircraft. (4) Latitude and longitude. c. Sea (1) Latitude and longitude. (2) Proximity to land. (Name city, country, etc.) 4, Number of objects. Formation type (if any), sketch if possible. 5. Observable celestial phenomena or planets that may account for the sighting. (Local facilities or organizations which follow such celestial phenomena should be consulted for such information.) 6. Distance of object from observer. a. Laterally or horizontally. b. Angle of elevation from horizon. c. Altitude. 7. Time in sight. 8. Appearance of object. a. Color. b. Shape. (Sketch if possible) c. Apparent construction. (Of what material or substance) d. Size. (1) Estimated size. (2) Size as it appeared from observer’s view. (Compared to known object) 9. Direction of flight. 10. Tactics or maneuvers. Vertical ascent or descent, horizontal, oscillating, fluttering, evasive, aggressive, erratic, etc, 11, Evidence of exhaust. a. Color of smoke. yb. Length and width. RESTRICTED -3-

RESTRICTED c. Odor (if any). d. Rate of evaporation. e. Does trail vary with sound? (spurts) 12. Effect on clouds. a. Opened path thru clouds. b. Forced cloud or mists, c. Reflected on cloud. d, Showed thru cloud. 13, Lights. a, Reflected or attached. b, Luminous c, Blinked on and off in relation to speed. 14, Support a, Wings. b. Aerodynamic list of fuselage. ¢c. Vertical jet. d. Rotating cylinder or cone. : e. Aerostatic lift (balloon or dirigible). 15. Propulsion. a. Propeller or jet. b. Rotor. ¢. Aerodynamic vanes (flapping or oscillating) (Katz Mayer effect). d. Visible exhaust or jet openings. 16, Control and stability. a. Fins b. Stabilizers (horizontal or vertical). (1) Size. (2) Shape. (3) Location. -4- RESTRICTED

RESTRICTED 17. Air ducts. a. Slots. b. Duct openings. 18. Speed - M.P.H. 19. Sound. a. Continuous whine or buzz. b. Roar, whistle, whoosh. c. Intermittent. 20. Manner of disappearance. a. Explode. (1) Possibility of fragments. (2) Other physical evidence. b. Faded from view. c., Disappeared behind obstacle. Relative to the Observer 1. Name of observer, 2. Address, 3. Occupation. 4, Place of business. a. Employer or employee. 5. Pertinent hobbies, a. Is observer amateur astronomer, pilot, engineer, etc. b. Length of time engaged in hobby (experience). 6, Ability to determine: a. Color. b. Speed of moving objects. c. Size at distance. 7. Reliability of observer. a. Sources. RESTRICTED Cul ye

RESTRICTED (1) Neighbors. (2) Police Dept. (3) FBI records. (4) Employer. 8. Notes relative to observer on: a. Sightings in general. b. How attention was drawn to object(s). (1) Sound. (2) Motion, (8) Glint of light. c. Degree of fatigue and duration of flight at time of sighting in cases where observer is airborne, 9, Witnesses, a, Addressees. b. Occupation. ec. Reliability. 10. Comments of interrogator regarding the intelligence and character of person interrogated. Relative to Radar Sightings 1. Re radars operating on ground. a. Observations of range, speed, altitude and size of target. b. Did target executive any turns? If so, what arigle (180°), etc. and what radius of turn. If radius of turn is not observable, how long did the target stay in the turn and what was its speed? c. Note particularly any separation of distant target into several targets upon approach. Track all if possible. 2. If airborne when object sighted. a. Were there any radar inductions or extra noise on radio circuits? b. Give estimates of size, speed, maneuvers, etc. GENERAL 1. Teletype sequences of local weather conditions. 2, Winds aloft report. -6- RESTRICTED

RESTRICTED 8. Local flight schedules of commercial, private and military aircraft flying in vicinity at the time. (Check Canadian activity if close to that border.) 4. Possible releases of testing devices in vicinity sent aloft by Ordnance, Navy, Air Force, Army, Weather Units, Research Organizations or any other. §. If object contacted earth, obtain soil samples within and without depression or spot where object landed (and then presumably departed) for purpose of making comparison of soils. 6. If object came sufficiently near other aircraft or known objects check surfaces with Geiger counters for possible radioactivity. Make comparisons with other unaffected aircraft objects, etc. 7. Obtain photographs (or original negatives) where available; if not, secure sketches of: a, Object. b. Surrounding terrain where observed. c. Place where it contacted earth (if this happened). d. Maneuvers. e. Formation if objects were more than two. 8. Secure signed statement. 9. Obtain fragments or physical evidence where possible. 10. Was any radio antenna to be observed, i.e., (any projections or extentions that might presum- ably be construed as such). Cc. P, CABELL Major General, USAF Director of Intelligence, Office of Deputy Chief of Staff, Operations DISTRIBUTION: Commanding Generals, Major Air Commands, ZI and Overseas All United States Air Attaches Director of Central Intelligence Special Assistant for Research and Intelligence, Department of State Director of Intelligence, GSUSA Chief of Naval Intelligence Commandant (INT), United States Coast Guard Director, Federal Bureau of Investigation RESTRICTED -7-

RESTRICTED DEPARTMENT OF THE AIR FORCE HEADQUARTERS UNITED STATES AIR FORCE DIRECTORATE OF INTELLIGENCE WASHINGTON 25, D. C. 15 February 1949 AIR INTELLIGENCE REQUIREMENTS MEMORANDUM NUMBER 4 UNCONVENTIONAL AIRCRAFT PART I - GENERAL 1. PURPOSE The purpose of this memorandum is twofold: a. To enunciate continuing Air Force requirements for information pertaining to sightings of unconventional aircraft and unidentified flying objects, including the so-called ‘‘Flying Discs.” b. To establish procedures for reporting such information. 2. RESCISSION Department of the Army Collection Memorandum Number 7, dated 21 January 1948, and letter, CSGID 425.1, dated 25 March 1948, both subject as above, which have been transferred to Air Force agencies for action, are herewith superseded. 3. REPORTING a, General (1) As complete an answer to the requirements enunciated in Part Il, as may be procur- able, should be dispatched by means of electrical transmission immediately after sightings, (2) Supplementary reports should be forwarded as available by the most expeditious means consistent with the importance of the information reported. b. Major Air Commands (Overseas) and Air Attaches (1) ‘Initial and supplementary cabled reports will be transmitted to the Director of Intelli- gence, Headquarters United States Air Force. Cables will contain the phase, ‘‘Pass to COMGENAMC WRIGHT-PATTERSON AFB, DAYTON, OHIO, ATTN: MCIAXO-3,’’ RESTRICTED 09-4892, AF

RESTRICTED (2) Supplementary written reports, prepared on AF Form 112, will be forwarded to the Director of Intelligence, Headquarters United States Air Force. (8) Commanding General, Air Materiel Command is authorized direct contact with major Air Commands (overseas) and organizations under their control in connection with the development of information on this subject. ¢. Major Air Commands (ZI) (1) Reports will be forwarded direct to the Commanding General, Air Materiel Command, Wright-Patterson Air Force Base, Dayton, Ohio, Attn: MCIAXO-3 by installations receiv- ing information pertaining to the requirements enunciated in Part II, (2) Copies of such reports may be supplied the Command Headquarters of the installation concerned, (3) A copy of all reports sent to Air Materiel Command in accordance with these instruc- tions will be forwarded at the same time to the Director of Intelligence, Headquarters United States Air Force, (4) Written reports will be submitted on AF Form 112. (5) Commanding General, Air Materiel Command is authorized direct contact with major Air Commands (ZI) and organizations under their control in connection with the develop- ment of information on this subject. d. Non-Air Force Agencies (1) Addressees other than those of the United States Air Force are requested to forward reports direct to the Commanding General, Air Materiel Command, Wright-Patterson Air Force Base, Dayton, Ohio, Attn: MCIAXO-3. (2) In order to reduce the time factor involved in transmission of this type of information it is requested that, wherever communications facilities permit, subordinate elements be authorized to communicate reports direct to the Commanding General, Air Materiel Com- mand, PART Il - REQUIREMENTS General 1. Date of sighting. a 2, Time of sighting (zonal by 24 hr. clock). 3. Where sighted (observer’s position): a. Ground (1) City, town. (2) Distance and direction from city or town, road, intersection, etc. (3) From building (story), yard, etc. (4) Map coordinates (if feasible) showing latitude and longitude. -2- RESTRICTED

RESTRICTED b. Air (1) Type aircraft, speed, altitude, direction of flight. (2) Distance and direction from city, town or known landmark. (8) Clock position of object from observer’s aircraft. (4) Latitude and longitude. c. Sea (1) Latitude and longitude. (2) Proximity to land. (Name city, country, etc.) 4, Number of objects. Formation type (if any), sketch if possible. 5. Observable celestial phenomena or planets that may account for the sighting. (Local facilities or organizations which follow such celestial phenomena should be consulted for such information.) 6. Distance of object from observer. a. Laterally or horizontally. b. Angle of elevation from horizon. c. Altitude. 7. Time in sight. 8. Appearance of object. a. Color. b. Shape. (Sketch if possible) c. Apparent construction. (Of what material or substance) d, Size. (1) Estimated size. (2) Size as it appeared from observer’s view. (Compared to known object) 9. Direction of flight. 10. Tactics or maneuvers. Vertical ascent or descent, horizontal, oscillating, fluttering, evasive, aggressive, erratic, etc. 11. Evidence of exhaust. a. Color of smoke. ’b. Length and width. RESTRICTED -3-

RESTRICTED c. Odor (if any). d. Rate of evaporation. e. Does trail vary with sound? (spurts) 12, Effect on clouds. a. Opened path thru clouds. b. Forced cloud or mists. c. Reflected on cloud. d, Showed thru cloud. 1 13, Lights, a. Reflected or attached. b. Luminous c. Blinked on and off in relation to speed. 14. Support a. Wings. b. Aerodynamic list of fuselage. c. Vertical jet. d. Rotating cylinder or cone. e. Aerostatic lift (balloon or dirigible). 15. Propulsion. a. Propeller or jet. b. Rotor. c. Aerodynamic vanes (flapping or oscillating) (Katz Mayer effect). d. Visible exhaust or jet openings. 16. Control and stability. a. Fins b. Stabilizers (horizontal or vertical). (1) Size. (2) Shape. (8) Location. -4- RESTRICTED

RESTRICTED 17. Air ducts. a. Slots. b. Duct openings. 18. Speed - M.P.H. 19. Sound. a. Continuous whine or buzz. b. Roar, whistle, whoosh. c. Intermittent. 20. Manner of disappearance. a. Explode. (1) Possibility of fragments. (2) Other physical evidence. b. Faded from view. c. Disappeared behind obstacle. Relative to the Observer 1, Name of observer. 2, Address. 3. Occupation. 4. Place of business. a. Employer or employee. 5. Pertinent hobbies, a. Is observer amateur astronomer, pilot, engineer, etc. b. Length of time engaged in hobby (experience), 6. Ability to determine: a. Color. b. Speed of moving objects. c. Size at distance. 7. Reliability of observer. a. Sources. RESTRICTED 250

RESTRICTED (1) Neighbors. (2) Police Dept. (3) FBI records. (4) Employer. s 8. Notes relative to observer on: a, Sightings in general. b. How attention was drawn to object(s). (1) Sound, (2) Motion. (3) Glint of light. ce, Degree of fatigue and duration of flight at time of sighting in cases where observer is airborne. 9. Witnesses, a, Addressees. b. Occupation, ec. Reliability. 10. Comments of interrogator regarding the intelligence and character of person interrogated. f Relative to Radar Sightings 1. Re radars operating on ground. a. Observations of range, speed, altitude and size of target. b. Did target executive any turns? If so, what angle (180°), etc. and what radius of turn. If radius of turn is not observable, how long did the target stay in the turn and what was its speed? ce. Note particularly any separation of distant target into several targets upon approach. Track all if possible. 2, If airborne when object sighted. a. Were there any radar inductions or extra noise on radio circuits? b. Give estimates of size, speed, maneuvers, etc. GENERAL 1. Teletype sequences of local weather conditions. 2. Winds aloft report. -6- RESTRICTED

RESTRICTED 8. Local flight schedules of commercial, private and military aircraft flying in vicinity at the time. (Check Canadian activity if close to that border.) 4. Possible releases of testing devices in vicinity sent aloft by Ordnance, Navy, Air Force, Army, Weather Units, Research Organizations or any other. 5. If object contacted earth, obtain soll samples within and without depression or spot where object landed (and then presumably departed) for purpose of making comparison of soils, 6. If object came sufficiently near other aircraft or known objects check surfaces with Geiger counters for possible radioactivity. Make comparisons with other unaffected aircraft objects, etc. 7, Obtain photographs (or original negatives) where available; if not, secure sketches of: a. Object. b. Surrounding terrain where observed. c. Place where it contacted earth (if this happened). d. Maneuvers. e. Formation if objects were more than two. 8. Secure signed statement. 9, Obtain fragments or physical evidence where possible. 10. Was any radio antenna to be observed, i.e., (any projections or extentions that might presum- ably be construed as such). Cc. P, CABELL Major General, USAF Director of Intelligence, Office of Deputy Chief of Staff, Operations DISTRIBUTION: Commanding Generals, Major Air Commands, ZI and Overseas All United States Air Attaches Director of Central Intelligence Special Assistant for Research and Intelligence, Department of State Director of Intelligence, GSUSA Chief of Naval Intelligence Commandant (INT), United States Coast Guard Director, Federal Bureau of Investigation RESTRICTED -7-

RESTRICTED ; DEPARTMENT OF THE AIR FORCE HEADQUARTERS UNITED STATES AIR FORCE DIRECTORATE OF INTELLIGENCE WASHINGTON 28, D. C. 15 February 1949 AIR INTELLIGENCE REQUIREMENTS MEMORANDUM NUMBER 4 UNCONVENTIONAL AIRCRAFT PART I - GENERAL 1. PURPOSE The purpose of this memorandum is twofold: a. To enunciate continuing Air Force requirements for information pertaining to sightings of unconventional aircraft and unidentified flying objects, including the so-called ‘Flying Discs.” b. To establish procedures for reporting such information. 2. RESCISSION Department of the Army Collection Memorandum Number 7, dated 21 January 1948, and letter, CSGID 425.1, dated 25 March 1948, both subject as above, which have been transferred to Air Force agencies for action, are herewith superseded. 8. REPORTING a, General (1) As complete an answer to the requirements enunciated in Part II, as may be procur- able, should be dispatched by means of electrical transmission immediately after sightings, (2) Supplementary reports should be forwarded as available by the most expeditious means consistent with the importance of the information reported. b. Major Air Commands (Overseas) and Air Attaches (1) Initial and supplementary cabled reports will be transmitted to the Director of Intelli- gence, Headquarters United States Air Force. Cables will contain the phase, ‘Pass to COMGENAMC WRIGHT-PATTERSON AFB, DAYTON, OHIO, ATTN: MCIAXO-3.’” RESTRICTED ¢9-4892, AF

RESTRICTED (2) Supplementary written reports, prepared on AF Form 112, will be forwarded to the Director of Intelligence, Headquarters United States Air Force. (3) Commanding General, Air Materiel Command is authorized direct contact with major Air Commands (overseas) and organizations under their control in connection with the development of information on this subject. c. Major Air Commands (ZI) (1) Reports will be forwarded direct to the Commanding General, Air Materiel Command, Wright-Patterson Air Force Base, Dayton, Ohio, Attn: MCIAXO-3 by installations receiv- ing information pertaining to the requirements enunciated in Part Il. (2) Copies of such reports may be supplied the Command Headquarters of the installation concerned, (3) A copy of all reports sent to Air Materiel Command in accordance with these instruc- tions will be forwarded at the same time to the Director of Intelligence, Headquarters United States Air Force. (4) Written reports will be submitted on AF Form 112. (5) Commanding General, Air Materiel Command is authorized direct contact with major Air Commands (ZI) and organizations under their control in connection with the develop- ment of information on this subject. d. Non-Air Force Agencies (1) Addressees other than those of the United States Air Force are requested to forward reports direct to the Commanding General, Air Materiel Command, Wright-Patterson Air Force Base, Dayton, Ohio, Attn: MCIAXO-3. (2) In order to reduce the time factor involved in transmission of this type of information it is requested that, wherever communications facilities permit, subordinate elements be authorized to communicate reports direct to the Commanding General, Air Materiel Com- mand, PART II - REQUIREMENTS General 1, Date of sighting. 2. Time of sighting (zonal by 24 hr. clock), 3. Where sighted (observer’s position): a. Ground (1) City, town. (2) Distance and direction from city or town, road, intersection, etc. (3) From building (story), yard, etc. (4) Map coordinates (if feasible) showing latitude and longitude. -8- RESTRICTED

RESTRICTED b. Air (1) Type aircraft, speed, altitude, direction of flight. (2) Distance and direction from city, town or known landmark. (8) Clock position of object from observer’s aircraft. (4) Latitude and longitude. c. Sea (1) Latitude and longitude. (2) Proximity to land. (Name city, country, etc.) 4. Number of objects. Formation type (if any), sketch if possible, 5. Observable celestial phenomena or planets that may account for the sighting. (Local facilities or organizations which follow such celestial phenomena should be consulted for such information.) 6. Distance of object from observer. a. Laterally or horizontally. b. Angle of elevation from horizon, c. Altitude. 7. Time in sight. 8. Appearance of object. a. Color. b. Shape. (Sketch if possible) c. Apparent construction. (Of what material or substance) d. Size, (1) Estimated size. (2) Size as it appeared from observer’s view. (Compared to known object) 9. Direction of flight. 10. Tactics or maneuvers. Vertical ascent or descent, horizontal, oscillating, fluttering, evasive, aggressive, erratic, etc, 11, Evidence of exhaust. a. Color of smoke. ‘b, Length and width. RESTRICTED -3-

RESTRICTED ¢, Odor (if any). d, Rate of evaporation. e. Does trail vary with sound? (spurts) 12. Effect on clouds. a. Opened path thru clouds. b. Forced cloud or mists. ¢. Reflected on cloud, d, Showed thru cloud. 18, Lights. a. Reflected or attached, b, Luminous ce. Blinked on and off in relation to speed. 14, Support a, Wings. b. Aerodynamic list of fuselage. c. Vertical jet. d. Rotating cylinder or cone. e. Aerostatic lift (balloon or dirigible). 15. Propulsion. a. Propeller or jet. b. Rotor. c. Aerodynamic vanes (flapping or oscillating) (Katz Mayer effect). da. Visible exhaust or jet openings. 16, Control and stability. a. Fins b. Stabilizers (horizontal or vertical). (1) Size. (2) Shape. (8) Location. -4- RESTRICTED

RESTRICTED 17. Air ducts. a. Slots. b. Duct openings. 18. Speed - M.P.H. 19. Sound. a. Continuous whine or buzz. b. Roar, whistle, whoosh, c. Intermittent. 20. Manner of disappearance. a. Explode. (1) Possibility of fragments. (2) Other physical evidence. b, Faded from view. ce. Disappeared behind obstacle. Relative to the Observer 1. Name of observer. 2. Address. 3. Occupation, 4. Place of business. a. Employer or employee. 5. Pertinent hobbies. a. Is observer amateur astronomer, pilot, engineer, etc. b. Length of time engaged in hobby (experience), 6, Ability to determine: a. Color, b. Speed of moving objects. c. Size at distance. 7. Reliability of observer. a. Sources, RESTRICTED -5-

RESTRICTED (1) Neighbors. (2) Police Dept. (3) FBI records. (4) Employer. 8, Notes relative to observer on: a. Sightings in general. b. How attention was drawn to object(s). (1) Sound. (2) Motion, (3) Glint of light. c. Degree of fatigue and duration of flight at time of sighting in cases where observer is airborne. 9, Witnesses, a, Addressees. b. Occupation. ec. Reliability. 10. Comments of interrogator regarding the intelligence and character of person interrogated. Relative to Radar Sightings 1, Re radars operating on ground, a. Observations of range, speed, altitude and size of target. b. Did target executive any turns? If so, what arigle (180°), etc. and what radius of turn. If radius of turn is not observable, how long did the target stay in the turn and what was its speed? c. Note particularly any separation of distant target into several targets upon approach. Track all if possible. 2. If airborne when object sighted. a, Were there any radar inductions or extra noise on radio circuits? b. Give estimates of size, speed, maneuvers, etc. GENERAL 1. Teletype sequences of local weather conditions. 2. Winds aloft report. = Gs RESTRICTED

RESTRICTED 8. Local flight schedules of commercial, private and military aircraft flying in vicinity at the time. (Check Canadian activity if close to that border.) 4, Possible releases of testing devices in vicinity sent aloft by Ordnance, Navy, Air Force, Army, Weather Units, Research Organizations or any other. 5. If object contacted earth, obtain soil samples within and without depression or spot where object landed (and then presumably departed) for purpose of making comparison of soils. 6. If object came sufficiently near other aircraft or known objects check surfaces with Geiger counters for possible radioactivity. Make comparisons with other unaffected aircraft objects, etc. 7. Obtain photographs (or original negatives) where available; if not, secure sketches of: a, Object. b, Surrounding terrain where observed. c. Place where it contacted earth (if this happened). d, Maneuvers, e. Formation if objects were more than two, 8. Secure signed statement. 9. Obtain fragments or physical evidence where possible. 10. Was any radio antenna to be observed, i.e., (any projections or extentions that might presum- ably be construed as such), Cc. P. CABELL Major General, USAF Director of Intelligence, Office of Deputy Chief of Staff, Operations DISTRIBUTION: Commanding Generals, Major Air Commands, ZI and Overseas All United States Air Attaches Director of Central Intelligence Special Assistant for Research and Intelligence, Department of State Director of Intelligence, GSUSA Chief of Naval Intelligence Commandant (INT), United States Coast Guard Director, Federal Bureau of Investigation RESTRICTED -7-