The Waterbury Democrat., 1931-07-29

NeW OTk NSpeCldiJ shOic hHou 25 amendments to the government airworthiness requirements for aircraft will be sought by manu- lecturers of commercial airplanes at A meeting with heads of the aeronautics branch, department of commerce, in Washington, D. C., July 31.
 The changes are being asked with a. view toward further tn- creasing the safety of aircraft and as a means of bringing the regu- Iations governing the design and construction of airplanes into con- formity with the advances that have been made in engineering in the past year. It is believed that the department of commerce will act favorably upon the suggestions of the manufacturers.
 The proposed amendments to the airworthiness requirements have been prepared by the engineering committee of the airDlane manu- facturers' section of the Aeronau- tical Chamber of Commerce Of America, Inc, national trade asso. citation of the aviation industry. They will be discussed and final draft prepared for presenttion to department of commerce officials at q general meeting of the manu- facturers' group to be held in Washington at the Carlton hotel, July 29-30.
 Ralph $. Damon, vice president and general manager of Curtiss- Wright Airplane company, Robert son, Mo, and chairman of the Air plane Manufacturers section of the chamber, has extended an invita- ton to all aircraft manufacturers and producers of structural afr plane parts, such as seaplane floats, to attend the two-day con ference in Washington preceding the meeting with the government officials.
 The amendments suggested by the airplane manufacturing inter- ests. that are adopted by the de- partment of commerce and writ ten into the airworthiness require ments, will take effect September l for the first time this year. Heretofore, changes made during the year have gone into effect on January l. The changes in the ef- fective date of the amendments adopted has been made to allow the manufacturers an opportunity of bringing out their annual mod els February 1 rather than April l as has been the case in the past.
 In many instances, the manu- lecturers are seeking more string ent requirements for aircraft. Chief among the tentative proposals IS one asking that light airplanes, which have been produced in large numbers since the first of the year, be required to exhibit the same spinning characteristics de- manded of heavier craft.
 Larger planes under the depart mept of commerce rules must re- cover from tail spin in less than a turn and q half after making SIX complete revolutions. The planes must do this with the controls in neutral and the power shut off. Knowing that the. new light air. planes are going into the hands of private individuals, who as a rule arc less skillful than the commer- cial pilots, the manufacturers are insisting that the light models be subjected to the same spinning test.
 The tentative amendments pre- pared by the engineering commit tee of the manufacturers section include the suggestion that the rate of climb of landplanes in feet per minute at sea level be "at least seven times the theoretical slow speed in miles per hour. but never less than 300 feet" The rate of climb for seaplanes. the proposed amendments say, should beat leasl CIf Anh but not less than 25O feet per min ute. This means, in the case of a land plane. which lands at a speed of so miles per hour, that its rate of climb must be at least 420 feet per minute, allowing It to clear an obstacle more than 400 feet high one minute after taking off from the ground.
 Other proposed amendments in clude a revision of the schedule of load factors with view to placigI them upon considerations of gross weight and speed range solely, and the stipulation that all liquid bat teries be enclosed, and the "con- atiner suitable drained and venti- lated" The manufacturers like wise would have the department of commerce issue specifications for fabric to be used in covering the wings and fuselages of light airplanes, and further stress the reauirement that safety belts for pilots and passengers must be ca pa b1e of withstanding a load of 1000 pounds.
 The engineering committee of the manufacturers section of the AeronauticaI Chamber of Com merce will hold q meeting at the Carlton hotel, July 28. 10 complete a study of the comments made by .La indiuidnal ma nIIfa CtlrerA on