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News | May 24, 2023

CH-47F Chinook: Replacement for Bad Engine Cowling Sealing Strip

BLUF: Replace a bad fairing sealing strip on the engine cowling with anti-chafe rubber bumpers, NSN 5340-01-054-1588, PN 0541588.

CH-47 helicopter repairers conduct a 160-hour phase maintenance inspection on a CH-47 Chinook helicopter.
Photo by Sgt. Jason Greaves
 
Mechanics, the lower cowling sealing strip on the CH-47F Chinook left- and right-hand (LH/RH) engine door assemblies will not stick or stay in place, and it deteriorates rapidly.
 
If you’ve got this problem with your F-model Chinook, here’s some good news. You can remove the chafed sealing strip and install anti-chafe rubber bumpers, NSN 5340-01-054-1588, PN 0541588 to protect the engine cowling edge from chafing. Here’s how:
 
Per the diagram below, on each lower cowling door assembly, drill eight (8) x 0.246-in holes approximately 7-in apart in which to install the rubber bumpers. On each retainer, drill two (2) x 0.246-in holes approximately 3-in apart.


Install anti-chafe rubber bumpers to protect lower engine cowlings per this diagram
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