Airworthiness Directive · Amendment 39-18996 · Fuselage
The Boeing Company Airplanes
(1) This AD applies to The Boeing Company Model 737-300, -400, and -500 series airplanes, certificated in any category, as identified in Boeing Alert Service Bulletin 737-53A1357, dated August 9, 2016.
(2) Installation of Supplemental Type Certificate (STC) ST01219SE (http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgstc.nsf/0/ebd1cec7b301293e86257cb30045557a/$FILE/ST01219SE.pdf) does not affect the ability to accomplish the actions required by this AD. Therefore, for airplanes on which STC ST01219SE is installed, a “change in product” alternative method of compliance (AMOC) approval request is not necessary to comply with the requirements of 14 CFR 39.17.
We are adopting a new airworthiness directive (AD) for certain The Boeing Company Model 737-300, -400, and -500 series airplanes. This AD was prompted by a report of fatigue cracking found in a certain fuselage frame common to the water tank support intercostal clip located between certain stringers. This AD requires inspections for any cracking of a certain fuselage frame, and repair if necessary. We are issuing this AD to address the unsafe condition on these products.
Before the accumulation of 34,000 total flight cycles or within 6,000 flight cycles after the effective date of this AD, whichever occurs later, do a high frequency eddy current (HFEC) inspection for any cracking in the fuselage frame at station (STA) 947.5 common to the water tank support intercostal clip located between stringers S-24R and S-25R, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 737-53A1357, dated August 9, 2016.
(1) If no cracking is found, repeat the inspection thereafter at intervals not to exceed 12,000 flight cycles.
(2) If any cracking is found: Before further flight, repair in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 737-53A1357, dated August 9, 2016.
Accomplishing the repair in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 737-53A1357, dated August 9, 2016, terminates the inspection requirements of paragraph (g) of this AD.
