Aft Engine Mount Center Link Orientation

航空发表于 2011-4-12 23:21:21

**** Hidden Message *****

航空发表于 2011-4-12 23:21:39

February 2002 WTT face to face CFMI / Boeing Proprietary Information - Unauthorized Disclosure, Use, or Export are Prohibited 1 Aft Engine Mount Center Link Orientation February 2002 WTT face to face CFMI / Boeing Proprietary Information - Unauthorized Disclosure, Use, or Export are Prohibited 2 Aft Engine Mount Center Link Orientation Event Summary • One operator reported center link assembly, P/N 310A2034-3, found installed reversed on one airplane  Occurred during overhaul of aft engine mount and not noted during aft mount installation on engine  Center link pawl pins requiring some effort to install  No difficulties in engine installation on airplane noted  Further investigation revealed 5 other cases of reversed center link on operator’s fleet • Second operator advised Boeing of difficulty in closing thrust reversers after No. 2 engine installation  All mounts were found properly mating with strut  Engine had undergone post installation engine runs with no anomalies  Engine was found to be rotated slightly outboard (right)  Engine was lowered, and inspection revealed center link, P/N 310A2034-7, was reversed February 2002 WTT face to face CFMI / Boeing Proprietary Information - Unauthorized Disclosure, Use, or Export are Prohibited 3 Aft Engine Mount Center Link Orientation No. 1 Outboard Location (Correct Installation) No. 2 Outboard Location (Incorrect Installation) February 2002 WTT face to face CFMI / Boeing Proprietary Information - Unauthorized Disclosure, Use, or Export are Prohibited 4 Aft Engine Mount Center Link Orientation Background • Center link is boomerang-shaped, attaches to hanger fitting in center and engine lugs at either side • Link almost symmetrical left-to-right • Installed spherical bearings almost identical in size  Difference in bearing bore diameter (1.00 inch versus 1.185 inch) not always apparent  Smaller left bearing and pin are primary load path  Larger right bearing and pin are fail safe load path. Not normally loaded due to clearance fit Result:  Link can be installed reversed in aft mount using existing pawl pins  Shifts aft end of engine 0.174-inch to right February 2002 WTT face to face CFMI / Boeing Proprietary Information - Unauthorized Disclosure, Use, or Export are Prohibited 5 Aft Engine Mount Center Link Orientation Background (cont) • Condition applies to the following aft engine mounts:  P/N 310A2034-3 Center Link installed on P/N 310A2030-6 Aft Engine Mount  P/N 310A2034-7 Center Link installed on P/N 310A2030-11 Aft Engine Mount (SAC)  P/N 310A2034-8 Center Link installed on P/N 310A2030-12 Aft Engine Mount (DAC)  Could be installed on any 737NG-series airplane Status • Reversed center link results in out-of-compliance configuration • If condition is suspected, visual inspection can be used to check orientation  If condition is confirmed, corrective action must be performed prior to further flight • The following documents were revised to further clarify existing installation:  AMM 71-21-03/401 12 February 2002 Revision  PPBU Figure 3-1 5 February 2002 Revision  CMM 71-21-37 1 March 2002 Revision • More information found in following:  FLEET TEAM Digest Article 737ng-FTD-71-01003, dated 20 Dec 2001  Boeing Service Letter to be released shortly (late Jan/early Feb) February 2002 WTT face to face CFMI / Boeing Proprietary Information - Unauthorized Disclosure, Use, or Export are Prohibited 6 Aft Engine Mount Center Link Orientation Recommendations • Ensure that the center link is installed correctly in aft mount after overhaul • During aft mount installation on engine, ensure no preload is required to install either of four pawl pins securing center link and side links to engine lugs • Make sure no excessive force is necessary to close the thrust reversers

kinran 发表于 2011-6-4 23:32:46

:victory: :victory:

bocome 发表于 2011-7-31 04:29:12

Aft Engine Mount Center Link Orientation

页: [1]

航空论坛_航空翻译_民航英语翻译_飞行翻译's Archiver

Aft Engine Mount Center Link Orientation