### Commercial Airplane Group 

# 757 Service Bulletin

Number: 757-35A0016 

## Revision Transmittal Sheet Date: November 11, 1999 Revision 1: June 15, 2000 ATA System: 3511

SUBJECT:OXYGEN - Crew Oxygen - Crew Oxygen System Low Pressure Flex Hose Replacement
This revision includes all pages of the service bulletin. COMPLIANCE INFORMATION RELATED TO THIS REVISION No more work is necessary on airplanes changed as shown in the initial release of this service bulletin. REASON FOR REVISION This revision is sent to advise operators of the following: The addition of the Joint Airworthiness Requirements (JAR) statement in the Approval section. The addition of the vendor equivalent part numbers in the Parts Necessary For Each Airplane section. Vertical lines are put on the left edge of each page, except in Paragraph 1.A., Effectivity, to show the location of important changes. Pages with no vertical lines have no important changes. REVISION HISTORY Original Release: November 11, 1999 Revision 1: June 15, 2000

757-35A0016 Revision Transmittal Page 1 of 1

### Commercial Airplane Group 

# 757 Service Bulletin

Number: 757-35A0016 

## Summary Date: November 11, 1999 Revision 1: June 15, 2000 ATA System: 3511

SUBJECT:OXYGEN - Crew Oxygen - Crew Oxygen System Low Pressure Flex Hose Replacement

CONCURRENT REQUIREMENTS None BACKGROUND The changes provided in this service bulletin will help prevent damage to the low pressure, oxygen, flex hoses that may be subjected to electrical current. An electrical grounding condition can cause the hose to melt or burn from smoke and/or fire. One operator has reported damaged oxygen supply hoses on the 757 in August of 1997. The damage occurred due to a short circuit in the Audio Select Panel. It sent an electrical current through the support structure to the flight crew, mask stowage box. This caused the spring inside the low pressure, oxygen hose to act as an electrical conductor and heat up. This caused the hose to burn through. Also, a similar occurrence on a 737, was reported due to improper maintenance. This service bulletin will replace low pressure, oxygen hoses with non-conductive hoses located on the flight deck. The replacement of the oxygen hoses will help prevent electrical current from passing through the supporting spring which can cause the hose to melt or burn from smoke and/or fire. Boeing Service Related Problem (SRP) 757-SRP-35-0014 is related to this service bulletin. ACTION(PRR 54530-213) Remove the crew oxygen boxes. Replace the existing low pressure hoses with the new non-conductive hoses. Install the crew oxygen boxes. Functional test the system. EFFECTIVITY 757-300 airplanes, line numbers 804, 810, 818, 839, 846, 849, and 855. NOTE: Service Bulletin 757-35A0015 is effective for the 757-200 airplanes.
COMPLIANCE Boeing recommends compliance at the earliest opportunity when manpower, material and facilities are available. INDUSTRY SUPPORT INFORMATION Boeing warranty remedies are not available for the configuration changes given in this service bulletin. MANPOWER Total Elapsed Time Man-Hours (Hours) 2.5 2.5 MATERIAL INFORMATION None

757-35A0016 Summary Page 1 of 2

### BOEING SERVICE BULLETIN 757-35A0016



### (TYPICAL) FWD APPLICABLE BOX HOSES AS REPLACE OXYGENV07610

November 11, 1999 757-35A0016 Revision 1: June 15, 2000 Summary Page 2 of 2

### Commercial Airplane Group 

# 757 Service Bulletin

Number: 757-35A0016 Date: November 11, 1999 Revision 1: June 15, 2000 ATA System: 3511

SUBJECT:OXYGEN - Crew Oxygen - Crew Oxygen System Low Pressure Flex Hose Replacement

THIS SERVICE BULLETIN IS SENT TO THE OPERATORS OF RECORD OF THE AIRPLANES SHOWN IN PARAGRAPH 1.A., EFFECTIVITY. IF AN AIRPLANE HAS BEEN LEASED OR SOLD, SEND THIS SERVICE BULLETIN TO THE NEW OPERATOR. IF APPLICABLE SPARES HAVE BEEN SOLD, SEND THIS SERVICE BULLETIN TO THE NEW OWNER. 1. PLANNING INFORMATION A. Effectivity 1. Airplanes Refer to Service Bulletin Index Document D624N001, Part 3 for Airplane Variable Number, Line Number, and Serial Number data. This service bulletin is for the airplanes shown below. An equivalent change is on subsequent production airplanes. Refer to PRR 54530-213 for data about this change. Service Bulletin 757-35A0015 is effective for the 757-200 airplanes. Airplane Models: 757-300 IDENTIFICATION BY CUSTOMER, CUSTOMER CODE, GROUP AND VARIABLE NUMBER CONDOR (CDF) NU701 NU721-NU726
IDENTIFICATION BY VARIABLE NUMBER NU701 NU721-NU726 2. Spares Affected None

November 11, 1999 757-35A0016 Revision 1: June 15, 2000 Page 1 of 20

### BOEING SERVICE BULLETIN 757-35A0016
B. Concurrent Requirements None C. Reason The changes provided in this service bulletin will help prevent damage to the low pressure, oxygen, flex hoses that may be subjected to electrical current. An electrical grounding condition can cause the hose to melt or burn from smoke and/or fire. One operator has reported damaged oxygen supply hoses on the 757 in August of 1997. The damage occurred due to a short circuit in the Audio Select Panel. It sent an electrical current through the support structure to the flight crew mask stowage box. This caused the spring inside the low pressure, oxygen hose to act as an electrical conductor and heat up. This caused the hose to burn through. Also, a similar occurrence on a 737, was reported due to improper maintenance. This service bulletin will replace low pressure, oxygen hoses with non-conductive hoses located on the flight deck. The replacement of the oxygen hoses will help prevent electrical current from passing through the supporting spring which can cause the hose to melt or burn from smoke and/or fire. Revision 1 is sent to advise operators of the following: The addition of the Joint Airworthiness Requirements (JAR) statement in the Approval section. The addition of the vendor equivalent part numbers in the Parts Necessary For Each Airplane section. Boeing Service Related Problem (SRP) 757-SRP-35-0014 is related to this service bulletin. D. Description Remove the crew oxygen boxes. Replace the existing low pressure hoses with the new non-conductive hoses. Install the crew oxygen boxes. Functional test the system. Revision 1 - No more work is necessary on airplanes changed as shown in the initial release of this service bulletin. An evaluation form is attached to this service bulletin. Please use this form to tell us what you think of the quality of this service bulletin. E. Compliance Boeing recommends compliance at the earliest opportunity when manpower, material and facilities are available. F. Approval Joint Airworthiness Requirements (JAR) compliance status may be found in the Service Bulletin Index, Section 1. This service bulletin was examined by the Federal Aviation Administration (FAA). The changes specified in this service bulletin comply with the applicable Federal Aviation Regulations (FAR) and are FAA approved. This service bulletin and the FAA approval were based on the airplane in its original Boeing delivery configuration or as modified by other FAA approved Boeing changes.

November 11, 1999 757-35A0016 Revision 1: June 15, 2000 2

### BOEING SERVICE BULLETIN 757-35A0016
If an airplane has a non-Boeing modification or repair that affects a component or system also affected by this service bulletin, the operator is responsible for obtaining appropriate regulatory agency approval before incorporating this service bulletin.

November 11, 1999 757-35A0016 Revision 1: June 15, 2000 3

### BOEING SERVICE BULLETIN 757-35A0016
G. Manpower The table below shows an estimate of the man-hours necessary to do this change for each airplane. This estimate is for direct labor only, done by an experienced crew. Adjust the estimate with operator man-hour data if necessary. The estimate does not include lost time. These are some examples of lost time: - Time to adjust to the workplace - Time to schedule the work - Time to examine the work - Time to cure the materials - Time to make the parts - Time to find the tools. Task Number of Persons Man-Hours Elapsed Time (Hours) Access 1 .75 .75 Replace hoses 1 1.0 1.0 Restore 1 .75 .75 TOTAL FOR EACH AIRPLANE 2.5 2.5 H. Weight and Balance Changes None I. Electrical Load Data Not changed

November 11, 1999 757-35A0016 Revision 1: June 15, 2000 4

### BOEING SERVICE BULLETIN 757-35A0016

J. References 1. Existing Data: a. Engineering Change Memo PRR 54530-213 b. Service Related Problem (SRP) 757-35-0014 c. 757 Maintenance Manual (AMM) Subject 12-15-08, 20-41-00, 35-00-00, 35-11-00, 35-11-51 d. Boeing Service Bulletin 757-35A0015, "Oxygen - Crew Oxygen - Crew Oxygen System Low Pressure Flex Hose Replacement" 2. Data supplied with this service bulletin: None 3. Installation Drawings Used in the Preparation of This Service Bulletin: Drawing Number Title 232N8001 OXYGEN MASK INSTL - CREW 208N0000 MANAGEMENT COLLECTOR - TUBING INSTL - DWG TREE AND GENERAL NOTES 208N4132 TUBING INSTL - UPPER R CAB STA 199.09 - 297 208N4133 TUBING INSTL - UPPER L CAB STA 199.09 - 297 These drawings were used to prepare this service bulletin. These drawings are not necessary to make the specified changes, and are not supplied with this service bulletin. These drawings may not be applicable to all airplane configurations or operators. K. Publications Changed Publication Chapter-Section 757 Maintenance Manual 35-11 757 Illustrated Parts Catalog 35-11 L. Interchangeability and Intermixability of Parts Refer to Paragraph 2.E., Existing Parts Accountability, for interchangeability and intermixability information.

November 11, 1999 757-35A0016 Revision 1: June 15, 2000 5

### BOEING SERVICE BULLETIN 757-35A0016

BLANK PAGE

November 11, 1999 757-35A0016 Revision 1: June 15, 2000 6

### BOEING SERVICE BULLETIN 757-35A0016

2. MATERIAL INFORMATION A. Material - Price and Availability The operator can supply the parts and materials shown in Paragraph 2.C., Parts Necessary For Each Airplane. As an alternative, operators can purchase the parts from Boeing Spares. This service bulletin does not show the Boeing price and supply data. B. Industry Support Information Boeing warranty remedies are not available for the configuration changes given in this service bulletin. C. Parts Necessary For Each Airplane 1. Kits: None 2. Parts and Materials Supplied by the Operator: QTY Boeing Part Number / Vendor Part Number Name

(a) 60B50059-606 / 38001-606 (b) Hose Assy (a) 60B50059-607 / 38001-607 (b) Hose Assy (a) For hose quantity requirements, see Illustrated Parts Catalog 35-11 for customer specific configuration. (b) HydraFlow (V24984) 13259 East 166th Street Cerritos, CA 90701-2203 (USA) D. Parts Necessary to Change Spares None

November 11, 1999 757-35A0016 Revision 1: June 15, 2000 7

### BOEING SERVICE BULLETIN 757-35A0016
E. Existing Parts Accountability The parts shown below are changed as shown in this service bulletin.

Existing Part Number RUC Name QTY New Part Number PNC RC 60B50059-70 DIS Hose Assy (a) 60B50059-606 S A 60B50059-81 DIS Hose Assy (a) 60B50059-607 S A (a) For hose quantity requirements, see Illustrated Parts Catalog 35-11 for customer specific configuration. RUC Recommended Use Code DIS - Discard the part. PNC Part Number Code S- To get a new part, use this part number in your order. - This is the part number after the change given in this service bulletin. - This part is used in production. RC Replacement Code A - Do not use the existing part to replace the new or changed part. F. Special Tooling - Price and Availability None G. Special Tooling Necessary to do this Service Bulletin No special tools or equipment are necessary to do the change in this service bulletin. But, maintenance and overhaul tools in the manuals given in Paragraph 1.J., References, can be necessary. Examine operator tool supply to make sure all necessary tools are available.

November 11, 1999 757-35A0016 Revision 1: June 15, 2000 8

### BOEING SERVICE BULLETIN 757-35A0016

3. ACCOMPLISHMENT INSTRUCTIONS GENERAL NOTES 1. The paragraphs identified with a letter give the general work instructions and the necessary tests. The instructions identified with numbers on the figures give the recommended sequence of steps. 2. Refer to the Boeing Standard Wiring Practices Manuals 20-10-11 and 20-10-12 for the wire installation procedures. 3. Obey all of the warnings and cautions given in the specified manual sections. WORK INSTRUCTIONS CAUTION: OXYGEN SYSTEM COMPONENTS REQUIRE SPECIAL CARE AND HANDLING PROCEDURES. REVIEW THE SAFETY AND MAINTENANCE PROCESSES SHOWN IN THE 757 AMM 35-00-00. A. Remove the oxygen stowage boxes as shown in 757 AMM 35-11-51 or operator's equivalent procedure. B. Remove the existing conductive oxygen hoses as shown in Figures 1, 2, 3, 4, and 5. NOTE: Ensure that the hose assembly elbows and unions do not move during hose replacement. Orientation of the elbows and unions are essential in maintaining proper clearances with other structure. C. Install the applicable new non-conductive oxygen hoses as shown in Figures 1, 2, 3, 4, and 5. D. Install the oxygen stowage boxes as shown in 757 AMM 35-11-51 or operator's equivalent procedure. E. Functional test the crew oxygen system as shown in 757 AMM 35-11-00, "Operational Test - Crew Oxygen Mask/Regulator" or operator's equivalent procedure. F. Put the airplane back to a serviceable condition.

November 11, 1999 757-35A0016 Revision 1: June 15, 2000 9

### BOEING SERVICE BULLETIN 757-35A0016

FIGURE TABLE OF CONTENTS Title Page FIGURE 1. OXYGEN BOX HOSE TYPICAL LOCATIONS.. . . . . . . . . . . . . . . . . . . . . . . 11 FIGURE 2. CAPTAIN AND FIRST OFFICER'S OXYGEN BOX HOSE REPLACEMENT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 FIGURE 3. RIGHT OBSERVER'S SEAT OXYGEN BOX HOSE REPLACEMENT. . . . . 16 FIGURE 4. LEFT OBSERVER'S SEAT OXYGEN BOX HOSE REPLACEMENT .. . . . . 18 FIGURE 5. SUPERNUMERARY OXYGEN BOX HOSE REPLACEMENT.. . . . . . . . . . . 20

November 11, 1999 757-35A0016 Revision 1: June 15, 2000 10

### BOEING SERVICE BULLETIN 757-35A0016

FWD FIGURE 4 FIGURE 3 FIGURE 5

FIGURE 2 SEE SEE SEE SEE

FIGURE 2 SEEV07611

FIGURE 1. OXYGEN BOX HOSE TYPICAL LOCATIONS November 11, 1999 SHEET 1 OF 1 757-35A0016 Revision 1: June 15, 2000 11

### BOEING SERVICE BULLETIN 757-35A0016



### FWD B SEE SEE A

FLIGHT COMPARTMENTV07612

FIGURE 2. CAPTAIN AND FIRST OFFICER'S OXYGEN BOX HOSE REPLACEMENT November 11, 1999 SHEET 1 OF 4 757-35A0016 Revision 1: June 15, 2000 12

### BOEING SERVICE BULLETIN 757-35A0016

4 3 2



## A CAPTAIN'S CONSOLE 1

INBD UP FWDV07613

FIGURE 2. CAPTAIN AND FIRST OFFICER'S OXYGEN BOX HOSE REPLACEMENT November 11, 1999 SHEET 2 OF 4 757-35A0016 Revision 1: June 15, 2000 13

### BOEING SERVICE BULLETIN 757-35A0016



### 1 23



## FIRST OFFICER'S CONSOLE 4



## B INBD UP FWDV07614

FIGURE 2. CAPTAIN AND FIRST OFFICER'S OXYGEN BOX HOSE REPLACEMENT November 11, 1999 SHEET 3 OF 4 757-35A0016 Revision 1: June 15, 2000 14

### BOEING SERVICE BULLETIN 757-35A0016
The step numbers shown below agree with the numbers shown in the circle symbols in the figure.

STEP TASK NAME REFERENCES QTY NOTES 1 Remove / Keep Oxygen Box 757 AMM 35-11-51 2
- 2 Remove / Discard Hose Assy 757 AMM 35-11-51 2 Discard the Hose Assy after recording the part number. 3 Install Hose Assy 757 AMM 35-11-51 2 See Existing Parts Accountability for applicable Hose Assy. 4 Install / Kept Oxygen Box 757 AMM 35-11-51 2
-

FIGURE 2. CAPTAIN AND FIRST OFFICER'S OXYGEN BOX HOSE REPLACEMENT November 11, 1999 SHEET 4 OF 4 757-35A0016 Revision 1: June 15, 2000 15

### BOEING SERVICE BULLETIN 757-35A0016

FWD



## A SEE A

3 2

4 1 FLIGHT COMPARTMENTV07615

FIGURE 3. RIGHT OBSERVER'S SEAT OXYGEN BOX HOSE REPLACEMENT November 11, 1999 SHEET 1 OF 2 757-35A0016 Revision 1: June 15, 2000 16

### BOEING SERVICE BULLETIN 757-35A0016
The step numbers shown below agree with the numbers shown in the circle symbols in the figure.

STEP TASK NAME REFERENCES QTY NOTES 1 Remove / Keep Oxygen Box 757 AMM 35-11-51 1
- 2 Remove / Discard Hose Assy 757 AMM 35-11-51 1 Discard the Hose Assy after recording the part number. 3 Install Hose Assy 757 AMM 35-11-51 1 See Existing Parts Accountability for applicable Hose Assy. 4 Install / Kept Oxygen Box 757 AMM 35-11-51 1
-

FIGURE 3. RIGHT OBSERVER'S SEAT OXYGEN BOX HOSE REPLACEMENT November 11, 1999 SHEET 2 OF 2 757-35A0016 Revision 1: June 15, 2000 17

### BOEING SERVICE BULLETIN 757-35A0016

FWD SEE A

1 2
4 3



## A FLIGHT COMPARTMENT

FWDV07617

FIGURE 4. LEFT OBSERVER'S SEAT OXYGEN BOX HOSE REPLACEMENT November 11, 1999 SHEET 1 OF 2 757-35A0016 Revision 1: June 15, 2000 18

### BOEING SERVICE BULLETIN 757-35A0016
The step numbers shown below agree with the numbers shown in the circle symbols in the figure.

STEP TASK NAME REFERENCES QTY NOTES 1 Remove / Keep Oxygen Box 757 AMM 35-11-51 1
- 2 Remove / Discard Hose Assy 757 AMM 35-11-51 1 Discard the Hose Assy after recording the part number. 3 Install Hose Assy 757 AMM 35-11-51 1 See Existing Parts Accountability for applicable Hose Assy. 4 Install / Kept Oxygen Box 757 AMM 35-11-51 1
-

FIGURE 4. LEFT OBSERVER'S SEAT OXYGEN BOX HOSE REPLACEMENT November 11, 1999 SHEET 2 OF 2 757-35A0016 Revision 1: June 15, 2000 19

### BOEING SERVICE BULLETIN 757-35A0016

14 2 3

FWDV07618

The step numbers shown below agree with the numbers shown in the circle symbols in the figure.

STEP TASK NAME REFERENCES QTY NOTES 1 Remove / Keep Oxygen Box 757 AMM 35-11-51 1
- 2 Remove / Discard Hose Assy 757 AMM 35-11-51 1 Discard the Hose Assy after recording the part number. 3 Install Hose Assy 757 AMM 35-11-51 1 See Existing Parts Accountability for applicable Hose Assy. 4 Install / Kept Oxygen Box 757 AMM 35-11-51 1
-

FIGURE 5. SUPERNUMERARY OXYGEN BOX HOSE REPLACEMENT November 11, 1999 SHEET 1 OF 1 757-35A0016 Revision 1: June 15, 2000 20

### Commercial Airplane Group 

# 757 Service Bulletin

Number: 757-35A0016 

## Evaluation Form Date: November 11, 1999 Revision 1: June 15, 2000 ATA System: 3511 Prepared By: Chris Starr

SUBJECT:OXYGEN - Crew Oxygen - Crew Oxygen System Low Pressure Flex Hose Replacement
Use this evaluation form to tell us what you think of the quality of this service bulletin. We will use the data that you give us to improve the quality of our service bulletins. NOTE: Please do not use this evaluation form to tell us to make changes to your manuals. To make these changes, please use a Publication Change Request (PCR) form. Please give us this data: (If necessary, please use the other side. Thank you for the time you used to give us your comments.) OPERATOR: TODAY'S DATE: PREPARED BY: TITLE: ORGANIZATION: TELEX CODE: TELEPHONE NUMBER: BASE: Please rate the quality of this service bulletin: (good)4321 (poor) Please rate the quality of the illustrations: (good)4321 (poor) Will you do the change given by this service bulletin? Yes No If not, please explain: Is this service bulletin easy to understand? Yes No If not, please explain: Is this service bulletin easy to use? Yes No If not, please explain: Are the Planning Information, Material Information, and Accomplishment Instructions accurate? Yes No If not, please explain: Is the Manpower estimate accurate? Yes No If not, please explain:
Give the completed evaluation form to your Boeing Field Service Representative or send the evaluation form directly to this address: Manager Service Bulletin Engineering Boeing Commercial Airplane Group P.O. Box 3707, Mail Stop 2H-37 Seattle, WA 98124-2207