Airworthiness Directive · Amendment 39-19670 · Landing gear system
Leonardo S.p.A. Helicopters
This AD applies to Leonardo S.p.A. Model AB139 and AW139 helicopters, certificated in any category, with an Increased Gross Weight 6,800 Kg kit part number (P/N) 4G0000F00111, and with a main landing gear (MLG) assembly with a P/N and serial number (S/N) listed in Figure 1 to paragraphs (a) and (e)(2) of this AD installed.
We are adopting a new airworthiness directive (AD) for certain Leonardo S.p.A. (Leonardo) Model AB139 and AW139 helicopters. This AD requires replacing screws installed on the left and right main landing gear (MLG) shock absorber assembly. This AD was prompted by a report that some screws may have been manufactured without meeting specifications. We are issuing this AD to address the unsafe condition on these products.
You are responsible for performing each action required by this AD within the specified compliance time unless it has already been accomplished prior to that time.
(1) Within the following compliance times, replace each screw P/N NAS1351-5H12P installed on an MLG shock absorber with a screw P/N 1652A0001-01. Re-identify the MLG assembly using black permanent ink by marking an “R” at the end of the S/N of the MLG assembly and cover with a transparent coating. For purposes of this AD, a “landing” is counted any time the helicopter lifts off into the air and then lands again regardless of the duration of the landing and regardless of whether the engine is shut down:
(i) For MLG assemblies with 26,800 or more landings, within 100 hours time-in-service (TIS).
(ii) For MLG assemblies with between 22,000 and 26,799 landings, within 300 hours TIS or before the MLG assembly accumulates 27,200 landings, whichever occurs first.
(iii) For MLG assemblies with less than 22,000 landings, within 1,200 hours TIS or before the MLG assembly accumulates 23,200 landings, whichever occurs first.
(2) After the effective date of this AD, do not install an MLG assembly with a P/N and S/N listed in Figure 1 to paragraphs (a) and (e)(2) of this AD on any helicopter unless the screw has been replaced and the MLG assembly re-identified as described in paragraph (e)(1) of this this AD.
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.
Aircraft
