Airworthiness Directive · Amendment 39-17681 · Fuel
The Boeing Company Airplanes
This AD applies to The Boeing Company Model 707-100 long body, -200, -100B long body, and -100B short body series airplanes; and Model 707-300, -300B, -300C, and -400 series airplanes; and Model 720 and 720B series airplanes; certificated in any category; as identified in Boeing 707 Service Bulletin 3532, dated January 12, 2012.
We are adopting a new airworthiness directive (AD) for certain The Boeing Company Model 707 airplanes; and Model 720 and 720B series airplanes. This AD was prompted by reports indicating that a standard access door was located where an impact-resistant access door was required, and stencils were missing from some impact-resistant access doors. This AD requires an inspection of the left- and right-hand wing fuel tank access doors to determine that impact-resistant access doors are installed in the correct locations, and to replace any door with an impact-resistant access door if necessary. This AD also requires an inspection for stencils and index markers on impact-resistant access doors, and application of new stencils or index markers if necessary. This AD also requires revising the maintenance program to incorporate changes to the airworthiness limitations section. We are issuing this AD to prevent foreign object penetration of the fuel tank, which could cause a fuel leak near an ignition source (e.g., hot brakes or engine exhaust nozzle), consequently leading to a fuel-fed fire.
Within 72 months after the effective date of this AD, do the actions specified in paragraphs (g)(1) and (g)(2) of this AD, in accordance with the Accomplishment Instructions of Boeing 707 Service Bulletin 3532, dated January 12, 2012.
(1) Do either a general visual inspection or ultrasonic non-destructive test of the left- and right-hand wing fuel tank access doors to determine whether impact-resistant access doors are installed in the correct locations. If any standard access door is found, before further flight, replace with an impact-resistant access door, in accordance with the Accomplishment Instructions of Boeing 707 Service Bulletin 3532, dated January 12, 2012.
(2) Do a general visual inspection of the left- and right-hand wing fuel tank impact-resistant access doors to verify stencils and index markers are applied. If a stencil or index marker is missing, before further flight, apply stencil or index marker, as applicable, in accordance with the Accomplishment Instructions of Boeing707 Service Bulletin 3532, dated January 12, 2012.
Within 60 days after the effective date of this AD, revise the maintenance program to incorporate Critical Design Configuration Control Limitations (CDCCL) Task 57-AWL-01, Impact-Resistant Fuel Tank Access Doors, of Subsection B, Airworthiness Limitations (AWLs) of the Boeing 707/720 Airworthiness Limitations (AWLs) Document D6-7552-AWL, Revision September 2012.
After accomplishing the revision required by paragraph (h) of this AD, no alternative actions (e.g., inspections), intervals, and/or CDCCLs may be used unless the actions, intervals, and/or CDCCLs are approved as an alternative method of compliance (AMOC) in accordance with the procedures specified in paragraph (j) of this AD.
