Airworthiness Directive · Amendment 39-15400 · Boeing Model 737-100, -200, -300, -400, and -500 Series Airplanes
Boeing Model 737-100, -200, -300, -400, and -500 Series Airplanes
Superseded. A later AD replaced this one: AD 2016-13-11. Comply with the one in force.
This AD applies to Boeing Model 737-100, -200, -300, -400, and -500 series airplanes, certificated in any category; as identified in Boeing Service Bulletin 737-57-1296, dated June 13, 2007.
We are adopting a new airworthiness directive (AD) for certain Boeing Model 737-100, -200, -300, -400, and -500 series airplanes. This AD requires repetitive inspections for fatigue cracking in the longitudinal floor beam web, upper chord, and lower chord located at certain body stations, and repair if necessary. This AD results from several reports of cracks in the center wing box longitudinal floor beams, upper chord, and lower chord. We are issuing this AD to detect and correct fatigue cracking of the upper and lower chords and web of the longitudinal floor beams, which could result in rapid loss of cabin pressure.
You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.
Do the various inspections for fatigue cracks in the longitudinal floor beam web, upper chord, and lower chord, located at the applicable body stations specified in the Accomplishment Instructions of Boeing Service Bulletin 737-57-1296, dated June 13, 2007, by doing all the actions specified in the Accomplishment Instructions of the service bulletin, except as provided by paragraph (g) of this AD. Do the inspections at the time specified in paragraph (f)(1) or (f)(2) of this AD, as applicable.
(1) For Groups 1 and 2 airplanes as identified in the service bulletin: Do the inspections at the applicable initial compliance time listed in paragraph 1.E., “Compliance,” of the service bulletin; except, where the service bulletin specifies a compliance time after the date on the service bulletin, this AD requires compliance within the specified compliance time after the effective date of this AD. Repeat the inspections thereafter at the intervals specified in paragraph 1.E., “Compliance,” of the service bulletin.
(2) For Group 3 airplanes as identified in the service bulletin: Do the inspections at the applicable initial compliance time listed in paragraph 1.E., “Compliance,” of the service bulletin; except, where the service bulletin specifies a compliance time after the date on the service bulletin, this AD requires compliance within the specified compliance time after the effective date of this AD. Repeat the inspections thereafter at the intervals specified in paragraph 1.E., “Compliance,” of the service bulletin.
(g) If any crack is found during any inspection required by this AD, and Boeing Service Bulletin 737-57-1296, dated June 13, 2007, specifies contacting Boeing for repair instructions: Before further flight, repair using a method approved in accordance with the procedures specified in paragraph (h) of this AD.
