AD 2009-20-01

(a) This airworthiness directive (AD) is effective October 26, 2009.

(b) None.

(c) This AD applies to Boeing Model 727-281 airplanes, certificated in any category, and equipped with auxiliary fuel tanks installed in accordance with Supplemental Type Certificate (STC) SA3449NM.

(d) This AD results from fuel system reviews conducted by the manufacturer. We are issuing this AD to prevent the potential of ignition sources inside fuel tanks, which, in combination with flammable fuel vapors, could result in fuel tank explosions and consequent loss of the airplane.

(e) You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.

(f) Within 60 days after the effective date of this AD, submit a report to the Manager, Los Angeles Aircraft Certification Office (ACO), FAA. Information collection requirements in this AD are approved by the Office of Management and Budget (OMB) under the provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.) and are assigned OMB Control Number 2120-0056. The report must include the following information:

(1) The airplane registration and auxiliary tank STC number installed.

(2) The usage frequency in terms of total number of flights per year and total number of flights for which the auxiliary tank is used.

(g) Within 90 days after the effective date of this AD, deactivate the auxiliary fuel tanks, in accordance with a deactivation procedure approved by the Manager of the Los Angeles ACO. Any auxiliary tank component that remains on the airplane must be secured and must have no effect on the continued operational safety and airworthiness of the airplane. Deactivation may not result in the need for additional instructions for continued airworthiness.

Note 1:

Appendix A of this AD provides criteria that might need to be included in the deactivation procedure. Timely approval is dependent on early submittal of the deactivation procedures.

Note 2:

For technical information, contact Dan Zevallos, Director of Program Management, Rogerson Aircraft Corporation, 2201 Alton Parkway, Irvine, California 92606; telephone (949) 442-2306; fax (949) 442-2322.

(h)(1) The Manager, Los Angeles ACO, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. Send information to ATTN: Serj Harutunian, Aerospace Engineer, Propulsion Branch, ANM-140L, FAA, Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood, California 90712-4137; telephone (562) 627-5254; fax (562) 627-5210.

(2) To request a different method of compliance or a different compliance time for this AD, follow the procedures in 14 CFR 39.19. Before using any approved AMOC on any airplane to which the AMOC applies, notify your principal maintenance inspector (PMI) or principal avionics inspector (PAI), as appropriate, or lacking a principal inspector, your local Flight Standards District Office. The AMOC approval letter must specifically reference this AD.

(i) None.

The auxiliary fuel tank deactivation procedure required by paragraph (g) of this AD might need to address the following actions.

(1) Permanently drain auxiliary fuel tanks, and clear them of fuel vapors to eliminate the possibility of out-gassing of fuel vapors from the emptied auxiliary tank.

Note: If applicable, removing the bladder might help eliminate out-gassing.

(2) Disconnect all electrical connections from the fuel quantity indication system (FQIS), fuel pumps if applicable, float switches, and all other electrical connections required for auxiliary tank operation, and stow them at the auxiliary tank interface.

(3) Disconnect all pneumatic connections if applicable, cap them at the pneumatic source, and secure them.

(4) Disconnect all fuel feed and fuel vent plumbing interfaces with airplane original equipment manufacturer (OEM) tanks, cap them at the airplane tank side, and secure them in accordance with a method approved by the FAA; one approved method is specified in AC 25-8 Auxiliary Fuel Tank Systems Installations. In order to eliminate the possibility of structural deformation during cabin decompression, leave open and secure the disconnected auxiliary fuel tank vent lines.

(5) Pull and collar all circuit breakers used to operate the auxiliary tank.

(6) Revise the weight and balance document, if required, and obtain FAA approval.

(7) Amend the applicable sections of the applicable airplane flight manual (AFM) to indicate that the auxiliary fuel tank is deactivated. Remove auxiliary fuel tank operating procedures to ensure that only the OEM fuel system operational procedures are contained in the AFM. Amend the Limitations Section of the AFM to indicate that the AFM Supplement for the STC is not in effect. Place a placard in the flight deck indicating that the auxiliary tank is deactivated. The AFM revisions specified in this paragraph may be accomplished by inserting a copy of this AD into the AFM.

(8) Amend the applicable sections of the applicable airplane maintenance manual to remove auxiliary tank maintenance procedures.

(9) After the auxiliary fuel tank is deactivated, accomplish procedures such as leak checks and pressure checks deemed necessary before returning the airplane to service. These procedures must include verification that the airplane FQIS and fuel distribution systems have not been adversely affected.

(10) Include with the operator's proposed procedures any relevant information or additional steps that are deemed necessary by the operator to comply with the deactivation and return the airplane to service.