SDR AALA20140119001

Service difficulty report · Bulkhead · Boeing 757223

Difficulty date: January 13, 2014
Submitted: January 27, 2014
Operation: Air carrier
Aircraft: N642AA
Make and model: Boeing 757223
Aircraft serial: 24600
Aircraft time: 70,525 hours, 24,975 cycles
System (JASC): 5412 · Nacelle/Pylon, Bulkhead/Firewall
Part: Bulkhead
Condition: Cracked
Location: Nr 1 Pylon
Stage of operation: IN
How discovered: V
Nature of condition: O
Precautionary procedure: K

As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.

What was found

NR 1 PYLON, INBD MID BULKHEAD HALF WAS BEING REPLACED DUE TO CRACK. THE FWD FASTENER HOLE COMMON TO THE MID BULKHEAD & THE LOWER SPAR CHORD WAS FOUND TO BE AT .415 INCHES WHICH IS BEYOND THE LIMITS SPECIFIED IN SB 757-54A0039 OF .3911INCHES MAXIMUM. ENGINEERING AUTHORIZATION B757-54-033265 DATED 01/17/2014 WAS ISSUED TO INCREASE THE HOLE SIZE TO .4990 INCHES. INSTALLED A FREEZE PLUG IN THE LOWER SPAR CHORD & INSTALLED FASTENER.