Airworthiness Directive · Amendment 39-17533 · Aircraft fuel system
The Boeing Company Airplanes
This AD applies to The Boeing Company Model 737-600, -700, -700C, -800, -900, and -900ER series airplanes, certificated in any category, with a date of issuance of the original airworthiness certificate or the date of issuance of the original export certificate of airworthiness before March 22, 2011.
We are adopting a new airworthiness directive (AD) for certain The Boeing Company Model 737-600, -700, -700C, -800, -900, and -900ER series airplanes. This AD was prompted by a report of an in-service occurrence of total loss of boost pump pressure of the fuel feed system, followed by loss of fuel system suction feed capability on one engine, and in-flight shutdown of the engine. This AD requires repetitive operational tests of the engine fuel suction feed of the fuel system, and other related testing and corrective action if necessary. We are issuing this AD to detect and correct loss of the engine fuel suction feed capability of the fuel system, which in the event of total loss of the fuel boost pumps could result in dual engine flameout, inability to restart the engines, and consequent forced landing of the airplane.
Do the requirements of paragraph (g)(1) or (g)(2) of this AD.
(1) Within 7,500 flight hours or 36 months after the effective date of this AD, whichever occurs first: Do the initial operational test identified in Airworthiness Limitation (AWL) No. 28-AWL-101, Engine Fuel Suction Feed Operational Test, of Section E., AWL—Fuel Systems of Section 9, Airworthiness Limitations (AWLs) and Certification Maintenance Requirements (CMRs), D626A001-CMR, Revision August 2011 or August 2012, of the Boeing 737-600/700/700C/800/900/900ER Maintenance Planning Data (MPD) Document. Repeat the test thereafter at intervals not to exceed 7,500 flight hours or 36 months, whichever is earlier. Thereafter, except as provided in paragraph (i) of this AD, no alternative procedure or repetitive test intervals will be allowed. If any test is not considered successful, as specified in AWL No. 28-AWL-101, before further flight, do either paragraph (g)(1)(i) or (g)(1)(ii) of this AD.
(i) Perform all related testing and corrective actions, using a method approved in accordance with the procedures specified in paragraph (i) of this AD.
(ii) Perform all related testing and corrective actions; and repeat the operational test specified in paragraph (g)(1) of this AD.
(2) Within 90 days after the effective date of this AD: Revise the maintenance program to incorporate the limitations specified in AWL No. 28-AWL-101, Engine Fuel Suction Feed Operational Test, of Section E., AWL—Fuel Systems of Section 9, Airworthiness Limitations (AWLs) and Certification Maintenance Requirements (CMRs), D626A001-CMR, Revision August 2012, of the Boeing 737-600/700/700C/800/900/900ER MPD Document. The initial compliance time for the task is within 7,500 flight hours or 36 months after the effective date of this AD, whichever occurs first.
After accomplishing the revision provided by paragraph (g)(2) of this AD, no alternative actions or repetitive test intervals may be used unless the actions or intervals are approved as an alternative method of compliance (AMOC) in accordance with the procedures specified in paragraph (i) of this AD.
