Airworthiness Directive · Amendment 39-21657 · Fuel control/turbine engines
GE Aviation Czech s.r.o. (Type Certificate Previously Held by WALTER Engines a.s., Walter a.s., and MOTORLET a.s.) Turboprop Engines
This AD applies to GE Aviation Czech s.r.o. (GEAC) (Type Certificate previously held by WALTER Engines a.s., Walter a.s., and MOTORLET a.s.) H75-200, H80-100, and H80-200 model turboprop engines.
The FAA is adopting a new airworthiness directive (AD) for all GE Aviation Czech s.r.o. (GEAC) H75-200, H80-100, and H80-200 model turboprop engines. This AD was prompted by several reports of engine gas generator speed (Ng) rollbacks occurring below idle on GEAC H75- 200, H80-100, and H80-200 model turboprop engines. This AD requires an inspection of a certain part number (P/N) fuel control unit (FCU) and, if deficiencies are detected, replacement of the FCU with a part eligible for installation. The FAA is issuing this AD to address the unsafe condition on these products.
(1) Within 100 flight hours (FHs) after the effective date of this AD, and thereafter at intervals not to exceed 100 FHs since the previous inspection, perform a functional inspection of the FCU, P/N LUN 6590.07-8, using the Accomplishment Instructions, paragraph 2.1.1, Ground Check Procedure, of GE Aviation Czech Alert Service Bulletin No. ASB-H80-73-00-00-0052[00]/ASB-H75-73-00-00-0022[00] (single document), Revision 00, dated February 6, 2020 (the ASB).
(2) If, during any functional inspection required by paragraph (g)(1) of this AD, the engine Ng is:
(i) Equal to or greater than 57% up to and including 60%, then no further action is required.
(ii) Equal to or greater than 55% but lower than 57%, then follow the steps 1 through 3 under “Ng speed is equal to or above 55% and below 57%” in the Accomplishment Instructions, paragraph 2.1.2, Ground check results evaluation, of the ASB.
(iii) Below 55%, then follow steps 1 and 2 under “Ng speed is below 55%” in the Accomplishment Instructions, paragraph 2.1.2, Ground check results evaluation, of the ASB.
Note 1 to paragraph (g)(2): In the Accomplishment Instructions, paragraph 2.1.2, of the ASB, where the ASB states “Do steps 1 thru 8 after the FCU adjustment,” do steps 1 through 7 of the Accomplishment Instructions, paragraph 2.1.1, in the ASB.
(3) During the next engine overhaul, or within 44 months, whichever occurs first after the effective date of this AD, remove the FCU, P/N LUN 6590.07-8, and replace it with a part eligible for installation.
After the effective date of this AD, do not install an FCU, P/N LUN 6590.07-8, onto any engine.
For the purpose of this AD, a part eligible for installation is an FCU, P/N LUN 6590.71-8.
Installing a part eligible for installation onto an engine as required by paragraph (g)(2) or (3) of this AD, as applicable, constitutes terminating action for the functional inspections required by paragraph (g)(1) of this AD for that engine.
The reporting requirements specified in paragraph 2.1.2 of the ASB are not required by this AD.
