AD 2000-01-05 Airworthiness Directives; Boeing Model 747 Series Airplanes

Models named: 747-100B, -200, -300, SP series. Read the applicability below — it usually turns on serial or part numbers too.

Model 747-100B, -200, -300, and SP series airplanes, equipped with Rolls Royce RB211-524B2, C2, and D4 engines; certificated in any category, as listed in the following service bulletins: Boeing Alert Service Bulletin 747-78A2148, dated June 1, 1995; Boeing Service Bulletin 747-78A2148, Revision 1, dated July 20, 1995; Boeing Service Bulletin 747-78-2136, dated May 11, 1995; and Boeing Service Bulletin 747-78-2156, dated October 31, 1996. Note 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (f) of this AD. The request should include an assessment of the [[Page 1053]] effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.

Required as indicated, unless accomplished previously. To prevent inadvertent deployment of a thrust reverser during flight and consequent reduced controllability of the airplane, accomplish the following: Restatement of Requirements of AD 99-18-03 Repetitive Inspections and Tests (a) Within 90 days after September 15, 1999 (the effective date of AD 99-18-03, amendment 39-11269): Perform the applicable inspections and tests of the thrust reverser control and indication system on each engine, in accordance with Part III.A. through III.G. of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-78A2148, dated June 1, 1995, or Boeing Service Bulletin 747- 78A2148, Revision 1, dated July 20, 1995. Repeat the applicable inspections and tests thereafter at intervals not to exceed 18 months, until accomplishment of paragraph (c) of this AD. Corrective Actions (b) If any inspection or test required by paragraph (a) of this AD cannot be successfully performed as specified in the service bulletin, or if any discrepancy is detected during any inspection or test, prior to further flight, repair in accordance with Boeing Alert Service Bulletin 747-78A2148, dated June 1, 1995, or Boeing Service Bulletin 747-78A2148, Revision 1, dated July 20, 1995. Additionally, prior to further flight, any failed inspection or test required by paragraph (a) of this AD must be repeated and successfully accomplished. Modification (c) Within 36 months after September 15, 1999: Install an additional locking system on the thrust reversers in accordance with the Accomplishment Instructions of Boeing Service Bulletin 747-78- 2156, dated October 31, 1996. Prior to or concurrent with accomplishment of Boeing Service Bulletin 747-78-2156, dated October 31, 1996: Accomplish Boeing Service Bulletin 747-78-2136, dated May 11, 1995; and Rolls-Royce Service Bulletins RB.211-71-B545, Revision 2, dated August 8, 1997, RB.211-71-B551, Revision 1, dated March 20, 1998, and RB.211-78-B552, dated June 21, 1996. Accomplishment of these actions constitutes terminating action for the repetitive inspections and tests required by paragraph (a) of this AD. Operational Checks (d) Within 3,000 flight hours after accomplishing the modification required by paragraph (c) of this AD, or within 1,000 flight hours after September 15, 1999, whichever occurs later: Perform operational checks of the number 2 and number 3 gearbox locks and of the air motor brake, in accordance with the procedures described in Appendix 1 (including Figure 1) of this AD. Repeat the operational checks thereafter at intervals not to exceed 3,000 flight hours. Corrective Actions (e) If any operational check required by paragraph (d) of this AD cannot be successfully performed as specified in the procedures described in Appendix 1 (including Figure 1) of this AD, or, if any discrepancy is detected during any operational check, prior to further flight, repair in accordance with the procedures specified in the Boeing 747 Airplane Maintenance Manual. Additionally, prior to further flight, any failed operational check required by paragraph (d) of this AD must be repeated and successfully accomplished. Continue to repeat the operational checks thereafter at intervals not to exceed 3,000 flight hours. Alternative Methods of Compliance (f) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Seattle ACO. Note 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Seattle ACO. Special Flight Permits (g) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished. Incorporation by Reference (h) Except as provided by paragraphs (d) and (e) of this AD, the actions shall be done in accordance with the applicable service bulletins: Boeing Service Bulletin 747-78-2136, dated May 11, 1995; Boeing Alert Service Bulletin 747-78A2148, dated June 1, 1995; Boeing Service Bulletin 747-78A2148, Revision 1, dated July 20, 1995; Boeing Service Bulletin 747-78-2156, dated October 31, 1996; Rolls-Royce Service Bulletin RB.211-78-B552, dated June 21, 1996; Rolls-Royce Service Bulletin RB.211-71-B545, Revision 2, dated August 8, 1997; or Rolls-Royce Service Bulletin RB.211-71-B551, Revision 1, dated March 20, 1998. This incorporation by reference was approved previously by the Director of the Federal Register as of September 15, 1999 (64 FR 47365, August 31, 1999). Copies may be obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 98124- 2207. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW, Renton, Washington; or at the Office of the Federal Register, 800 North Capitol Street, NW, suite 700, Washington, DC. (i) This amendment becomes effective on January 24, 2000. Appendix 1-- Gearbox Lock and Air Motor Brake Test A. General To do the test of the gearbox locks and air motor brake, you must do the steps that follow: (a) Do the deactivation procedure of the thrust reverser system. (b) Do the test of the air motor brake. (c) Do the test of the gearbox locks. (d) Do the activation procedure of the thrust reverser system. B. Equipment (1) CP30784--INA Access Platform, Rolls-Royce (2) CP30769--Protection Pads, Rolls-Royce (3) CP30785--Access Stools, Rolls-Royce (4) UT1293/1--Load Tool, Rolls-Royce (2 required) C. Procedure (Fig. 1) Warning: Do the Deactivation Procedure of the Thrust Reverser System, Which Must Include the Installation of Lock Bars (or Blockers), to Prevent the Accidental operation of the Thrust Reverser. The Accidental Operation of the Thrust Reverser Could Cause Injury to Persons and Damage to Equipment. (1) Do the deactivation procedure of the thrust reverser in the forward thrust position for ground maintenance. (2) Use a 0.25-inch (6.4-mm) square drive to turn the manual lock release screw to release the No. 2 and No. 3 gearbox locks. Note: It is not always easy to turn the manual lock release screws. This is because of a preload in the systems. To release the preload, lightly turn the manual cycle and lockout shafts in the stow direction. (a) Make sure the lock indicators are extended at gearboxes No. 2 and No. 3. (3) Do a test of the air motor brake: (a) If You Use the Load Tools; Try to move the translating cowl in the extend direction as follows: (1) Remove the lock bars that you installed in the deactivation procedure. (2) Install the load tools through the cutouts and into the No. 2 and No. 3 gearboxes. (3) Attach the torque wrenches to the load tools. (4) Try to move the translating cowl in the extend direction. (b) If You Do Not Use the Load Tools; Try to move the translating cowl in the extend direction as follows: (1) Remove the lock bars that you installed in the deactivation procedure. (2) Put the 0.25-inch (6.4-mm) square drive extensions into the manual cycle and lockout shaft at the No. 2 and No. 3 gearboxes. (a) Attach the standard drive tools. (3) Try to move the translating cowl in the extend direction. (c) If the translating cowl moves, replace the air motor and shutoff valve. (4) Do a test of the gear box locks: Note: The steps that follow are for the No. 3 gearbox. Then, do these steps again for the No. 2 gearbox. [[Page 1054]] (a) Install the lock bars in the manual cycle and lockout shafts at the No. 2 and No. 3 gearboxes. (b) Install the INA access platform in the exhaust mixer duct. (c) Install the protection pads and the access stools. (d) Release the air motor brake: (1) Open the air motor access and pressure relief panel. (2) Pull the air motor brake release handle forward and turn it counterclockwise to lock the handle in its position. (e) Turn the manual lock release screw clockwise to engage the No. 3 gearbox lock. (1) Make sure that the lock indicator is retracted (under the surface) at gearbox No. 3. (f) Make sure No. 2 gearbox lock is released. (1) Make sure the lock indicator is extended at gearbox No. 2. (g) If You Use the Load Tools; Do a check of the lock dogs as follows: (1) Remove the lock bars from the No. 2 and No. 3 gearboxes. (2) Install the load tool through the cutout and into the No. 3 gearbox. (3) Attach the torque wrench to the load tool. Caution: Do Not Apply a Torque Load of More Than 30 Pound-Inches (3.4 Newton-Meters) to the Manual Cycle and Lock Out Shaft. A Larger Torque Load Can Cause Damage to the Mechanism. (4) Apply a torque counterclockwise through the manual wind position of the No. 3 gearbox. (a) If the translating cowl does not move, the lock bar touched one of the two lock dogs. (b) If the translating cowl moved, lock the thrust reverser until the No. 3 gearbox is replaced. (5) Turn the manual lock release screw counterclockwise to release the gearbox lock. (a) Make sure that the indication rod comes out of the No. 3 gearbox. (6) Turn the manual cycle and lockout shaft counterclockwise \1/ 4\ turn. (7) Turn the manual lock release screw clockwise to engage the No. 3 gearbox lock. (a) Make sure that the indication rod is fully retracted (under the surface). Caution: Do Not Apply a Torque Load of More Than 30 Pound-Inches (3.4 Newton-Meters) to the Manual Cycle and Lockout Shaft. A Greater Torque Load Can Cause Damage to the Mechanism. (8) Apply a torque counterclockwise through the manual wind position of the No. 3 gearbox. (a) If the manual cycle and lockout shaft can not be turned more than approximately \1/4\ turn, the second lock dog is serviceable. (b) If the manual cycle and lockout shaft can be turned more than approximately \1/4\ turn, the second lock dog is unserviceable. Lock the thrust reverser until the No. 3 gearbox is replaced. Note: The two lock dogs are found \1/2\ turn apart when you use the manual cycle and lockout shaft. If necessary, do the check again to make sure that the lock dogs are serviceable. (9) Do the procedure given above for the No. 2 gearbox lock. (h) If You Do Not Use the Load Tools; Do a check of the lock dogs as follows: (1) Remove the lock bars from the No. 2 and No. 3 gearboxes. (2) Put the 0.25-inch (6.4-mm) square drive extensions into the manual cycle and lockout shaft at the No. 2 and No. 3 gearboxes. (a) Attach the standard drive tools. Caution: Do Not Apply a Torque Load of More Than 30 Pound-Inches (3.4 Newton-Meters) to the Manual Cycle and Lockout Shaft. A Larger Torque Load Can Cause Damage to the Mechanism. (3) Apply a torque counterclockwise through the manual wind position of the No. 3 gearbox. (a) If the translating cowl does not move, the lock bar touched one of the two lock dogs. (b) If the translating cowl moved, lock the thrust reverser until the No. 3 gearbox is replaced. (4) Turn the manual lock release screw counterclockwise to release the gearbox lock. (a) Make sure that the indication rod comes out of the No. 3 gearbox. (5) Turn the manual cycle and lockout shaft counterclockwise \1/ 4\ turn. (6) Turn the manual lock release screw clockwise to engage the No. 3 gearbox lock. (a) Make sure that the indication rod is fully retracted (under the surface). Caution: Do Not Apply a Torque Load of More Than 30 Pound-Inches (3.4 Newton-Meters) to the Manual Cycle and Lockout Shaft. A Greater Torque Load Can Cause Damage to the Mechanism. (7) Apply a torque counterclockwise through the manual wind position of the No. 3 gearbox. (a) If the manual cycle and lockout shaft can not be turned more than approximately \1/4\ turn, the second lock dog is serviceable. (b) If the manual cycle and lockout shaft can be turned more than approximately \1/4\ turn, the second lock dog is unserviceable. Lock the thrust reverser until the No. 3 gearbox is replaced. Note: The two lock dogs are found \1/2\ turn apart when you use the manual cycle and lockout shaft. If necessary, do the check again to make sure that the lock dogs are serviceable. (8) Do the procedure given above for the No. 2 gearbox lock. (5) Install the lock bars in the manual cycle and lockout shafts at the No. 2 and No. 3 gearboxes. (6) Apply the air motor manual brake: (a) Turn the air motor brake release handle clockwise and then release. (b) Close the air motor access and pressure relief panel. (7) Make sure the No. 2 and No. 3 gearbox locks are released. (a) Make sure the lock indicator rods are extended at the No. 2 and No. 3 gearboxes. (8) If You Use the Load Tools; Try to move the translating cowl in the extend direction as follows: (a) Remove the lock bars from the No. 2 and No. 3 gearboxes. (b) Install the load tools through the cutouts and into the No. 2 and No. 3 gearboxes. (c) Attach the torque wrenches to the load tools. (d) Try to move the translating cowl in the extend direction. (9) If You Do Not Use the Load Tools; Try to move the translating cowl in the extend direction as follows: (a) Remove the lock bars from the No. 2 and No. 3 gearboxes. (b) Put the 0.25-inch (6.4-mm) square drive extensions into the manual cycle and lockout shaft at the No. 2 and No. 3 gearboxes. (1) Attach the standard drive tools. (c) Try to move the translating cowl in the extend direction. (10) If the translating cowl moves, do the full test again. (a) If the translating sleeve moves again, lock the thrust reverser until you can replace the two locking gearboxes and the air motor and shutoff valve. (11) Remove the access stools and protection pads. (12) Remove the INA access platform from the exhaust mixer duct. (13) Do the activation procedure of the thrust reverser system. (14) Do the functional test of the thrust reverser system. BILLING CODE 4910-13-U [[Page 1055]] [GRAPHIC] [TIFF OMITTED] TR07JA00.000 Issued in Renton, Washington, on January 3, 2000. Vi L. Lipski, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 00-374 Filed 1-6-00; 8:45 am] BILLING CODE 4910-13-C