Airworthiness Directive · Amendment 39-19209 · Engine controls section
Honeywell International Inc. Turbofan Engines
This AD applies to all Honeywell International Inc. AS907-1-1A model turbofan engines with engine electronic control unit (ECU), part numbers (P/Ns) 2119576-1001 through -1011, installed; AS907-2-1A model turbofan engines with ECU, P/N 2119576-1102, installed; AS907-2-1G model turbofan engines with ECU, P/Ns 2119576-3002 and -3102, installed; and AS907-3-1E model turbofan engines with ECU, P/Ns 2119576-4102 and -4103, installed with applicable engine serial numbers (S/Ns) in Table 3 of Honeywell Service Bulletin (SB) AS907-76-9021, Revision 1, dated April 20, 2017 that are not sealed in the areas identified in Figures 1 through 13 of Honeywell SB AS907-76-9021, Revision 1, dated April 20, 2017.
We are adopting a new airworthiness directive (AD) for certain Honeywell International Inc. AS907 series turbofan engines. This AD was prompted by seven loss-of-thrust-control events attributed to water intrusion of the engine electronic control unit (ECU). This AD requires applying sealant to identified areas of the ECU and requires inserting a copy of certain airplane operating procedures into the applicable flight manuals. We are issuing this AD to address the unsafe condition on these products.
(1) For applicable engines and ECUs, within 200 hours time in service, or 9 months after the effective date of this AD, whichever occurs first, do the following:
(i) If no sealant has been applied to the ECU in the areas identified in Figures 1 through 13 of Honeywell SB AS907-76-9021, Revision 1, dated April 20, 2017, apply sealant to the ECU using the Accomplishment Instructions, paragraph 3.C., of Honeywell SB AS907-76-9021, Revision 1, dated April 20, 2017.
(ii) Reserved.
(2) Within 60 days after the effective date of this AD, for all airplanes that have an affected engine installed with an affected ECU not in compliance with paragraph (g)(1) of this AD, insert a copy of Figure 1, 2, or 3 to paragraph (g) of this AD, as applicable to your airplane, into the Emergency Procedures Section of the Airplane Flight Manual (AFM) and perform the following steps as necessary:
(i) If a cyan warning is announced, before next flight, check the current fault messages in the Maintenance Data Computer (MDC)/Onboard Messaging System (OMS) for any of the following:
(A) FADEC ECU A
(B) FADEC ECU B
(C) THROTTLE LEVER 1A
(D) THROTTLE LEVER 1B
(E) THROTTLE RIGGING 1A
(F) THROTTLE RIGGING 1B
(ii) Replace the ECU if any of the fault messages listed in paragraph (g)(2)(i) of this AD are in the MDC OMS. Refer to Honeywell Operating Information Letter OIAS907-0001R00, dated March 14, 2017, for guidance on returning and replacing the ECU.
(iii) Continued flight is permitted if none of the fault messages listed in paragraph (g)(2)(i) of this AD are in the MDC OMS, or if paragraph (g)(2)(ii) of this AD was accomplished.
(i) Do not install an ECU if any of the fault messages listed in paragraph (g)(2)(i) of this AD are in the MDC OMS.
(ii) Do not install an ECU that has a P/N listed in paragraph (c) of this AD unless it was sealed as specified in paragraph (g)(1)(i) of this AD.
Remove from the AFM, Figure 1, 2, or 3 to paragraph (g) of this AD, after paragraph (g)(1)(i) of this AD is accomplished.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
Engines
