Airworthiness Directive · Amendment 39-14007 · Boeing Model 737-600, -700, -700C, -800, and -900 Series Airplanes
Boeing Model 737-600, -700, -700C, -800, and -900 Series Airplanes
Superseded. A later AD replaced this one: AD 2021-21-09. Comply with the one in force.
This AD applies to Boeing Model 737-600, -700, -700C, -800, and -900 series airplanes, certificated in any category; as identified in Boeing Service Bulletin 737-53-1251, dated June 3, 2004.
The FAA is adopting a new airworthiness directive (AD) for certain Boeing Model 737-600, -700, -700C, -800, and -900 series airplanes. This AD requires repetitive detailed, low frequency eddy current, and high frequency eddy current inspections of the webs of the aft pressure bulkhead at body station 1016 for cracks, and corrective action if necessary. This AD is prompted by a report of cracks found, during fatigue testing, at several of the fastener rows in the web lap splices at the dome apex of the aft pressure bulkhead. We are issuing this AD to detect and correct fatigue cracks in the webs of the aft pressure bulkhead, which could result in rapid decompression of the airplane.
You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.
Prior to accumulating 26,000 total flight cycles or within 4,000 flight cycles after the effective date of this AD, whichever occurs later: Do a detailed inspection, low frequency eddy current inspection, and high frequency eddy current inspection of the webs of the aft pressure bulkhead at body station 1016 for cracks, in accordance with Boeing Service Bulletin 737-53-1251, dated June 3, 2004. Repeat the inspections thereafter at intervals not to exceed 4,000 flight cycles.
Note 1: For the purposes of this AD, a detailed inspection is: “An intensive examination of a specific item, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at an intensity deemed appropriate. Inspection aids such as mirror, magnifying lenses, etc., may be necessary. Surface cleaning and elaborate procedures may be required.”
If any crack is found during any inspection required by paragraph (f) of this AD: Before further flight, repair according to a method approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA; or according to data meeting the certification basis of the airplane approved by an Authorized Representative for the Boeing Delegation Option Authorization (DOA) Organization who has been authorized by the Manager, Seattle ACO, to make those findings. For a repair method to be approved, the approval must specifically reference this AD.
