76-15-09 ROLLS-ROYCE (1971) LIMITED: Amendment 39-2682. Applies to Rolls-Royce RB211-22 series engines that do not incorporate Rolls-Royce Modifications 3310, and 3738.
Compliance is required as indicated.
To prevent inflight engine shutdown that could result from cracks in the engine intermediate casing, accomplish the following:
(a) Within the next 50 hours engine time in service after the effective date of this AD, or before the accumulation of the lesser of 400 hours total engine time in service or 280 cycles, whichever occurs later, unless already accomplished in accordance with Revision 5 of Rolls-Royce Service Bulletin RB211-72-A3077, dated July 5, 1976, comply with paragraph (b) of this AD.
(b) Inspect the outside of the intermediate compressor casing for axial cracks in the outer main casing wall, using the dye penetrant method -
(1) In the vicinity of the internal wheel case oil scavenge boss and the borescope access port at the 5 o'clock location when viewed from the rear; and
(2) In the vicinity of the internal gearbox oil vent and pressure tube connections (ground handling point) at the 9 o'clock location when viewed from the rear.
(c) If a crack is found during any inspection required by this AD, and that crack, either
(1) Has reached either the oil scavenge boss which is located at the 5 o'clock location or the ground handling point which is located at the 9 o'clock location;
(2) Has progressed through either the oil scavenge boss which is located at the 5 o'clock location or the ground handling point which is located at the 9 o'clock location; or
(3) Is in close proximity to and appears to be approaching either the oil scavenge boss which is located at the 5 o'clock location or the ground handling point which is located at the 9 o'clock location; before further flight, except that the engine may be operated on an aircraft which is flown in accordance with FARs 21.197 and 21.199 to a base wherereplacement can be accomplished, replace the cracked casing with a serviceable casing of either steel, Silcosetcoated aluminum or aluminum. If replacement is accomplished with other than a Silcoset-coated aluminum casing or steel casing continue to inspect the replacement casing for cracks in accordance with paragraph (b) of this AD at intervals established in paragraph (e) of this AD.
(d) If a crack is found during any inspection required by this AD which does not conform to any of the criteria of paragraph (c) of this AD and which has progressed from a point forward to a point aft of the oil scavenge boss which is located at the 5 o'clock location, or from a point forward to a point aft of the ground handling point which is located at the 9 o'clock location, replace the cracked casing with a serviceable casing of either steel, Silcoset-coated aluminum or aluminum, before further flight, except that the engine may be operated on an aircraft which is flown, either -
(1) Inaccordance with FARs 21.197 and 21.199 to a base where replacement can be accomplished; or
(2) For 7 or less additional cycles, provided that - (i) There is no visible loss of oil; (ii) Engine oil consumption remains within the limits established for the engine; and (iii) All other engines on the aircraft are inspected in accordance with the provisions of this AD at the same time as the affected engine and are found free of any of the cracks specified in paragraphs (c) and (d) of this AD.
If a cracked casing is replaced with a serviceable aluminum casing other than a Silcoset-coated aluminum casing, continue to inspect the replacement casing for cracks in accordance with paragraph (b) of this AD at intervals established in paragraph (e) of this AD.
(e) Repeat the inspection specified in paragraph (b) of this AD at intervals not to exceed -
(1) 300 cycles from the last inspection for engines incorporating either Rolls-Royce Service Bulletin 72-3650, dated January 20, 1975, or Rolls-Royce Service Bulletin 72-3720, Revision 2, dated March 21, 1975, or an FAA-approved equivalent of either;
(2) 300 cycles from the last inspection for engines incorporating Rolls-Royce Service Bulletin 72- 3681, dated October 7, 1974, or an FAA-approved equivalent, until modified in accordance with paragraph (f) of this AD; or
(3) 150 cycles from the last inspection for engines which have not incorporated any of the modifications specified in paragraph (e)(1) or (e)(2) of this AD, until modified in accordance with paragraph (f) of this AD.
(f) For engines with aluminum compressor casings other than Silcoset-coated aluminum casings on which no oil passageway sleeves have been incorporated or which have been modified in accordance with Rolls- Royce Service Bulletin 72-3681, dated October 7, 1974, within the next 500 hours engine time in service after the effective date of this AD, install a sleeve at the 5 o'clock location, viewed from the rear, into the intermediate case internal wheel case oil return passageway in accordance with either Rolls-Royce Service Bulletin 72-3650, dated January 20, 1975, or Rolls-Royce Service Bulletin 72-3720, Revision 2, dated March 21, 1975, or an equivalent of either, approved by the Chief, Aircraft Certification Staff, Europe, Africa and Middle East Region, Federal Aviation Administration, c/o American Embassy, APO New York, N.Y. 09667 and thereafter inspect the casing for axial cracks in accordance with paragraph (b) of this AD at intervals not to exceed 300 cycles from the last inspection.
(g) For the purpose of this AD, the number of cycles equals the number of flights that involve an engine operating sequence consisting of engine starting, takeoff, operation, landing, and engine shutdown.
This supersedes Amendment 39-2170 (40 FR 16190), AD 75-08-18.
This amendment becomes effective July 22, 1976.