Airworthiness Directive · Amendment 39-21675 · Stabilizer control system
Leonardo S.p.a. Helicopters
This AD applies to Leonardo S.p.a. Model A109S helicopters and AW109SP helicopters, certificated in any category, with vertical fin vibration absorber installation part number (P/N) 109-B810-79-101 installed.
The FAA is adopting a new airworthiness directive (AD) for Leonardo S.p.a. (Leonardo) Model A109S and AW109SP helicopters with a certain part-numbered vertical fin vibration absorber installation installed. This AD requires repetitive inspections of the vertical fin vibration absorber installation and the surrounding structure and depending on the inspection results, removing certain parts from service. This AD also prohibits installing certain part-numbered vertical fin vibration absorber installations on any helicopter. This AD was prompted by a report of cracks and damage detected on the vertical fin absorber installation and surrounding structure during scheduled inspections. The FAA is issuing this AD to address the unsafe condition on these products.
(1) Within 30 hours time-in-service (TIS) after the effective date of this AD, and thereafter at intervals not to exceed 100 hours TIS:
(i) Remove the vertical fin vibration absorber installation P/N 109-B810-79-101, and using a mirror and light source, visually inspect the rib assembly P/N 109-0372-53-201 for hole elongation, fretting, and cracks. If there is any hole elongation, fretting, or cracks, before further flight, remove rib assembly P/N 109-0372-53-201, shim P/N 109-0372-53-211, doubler P/N 109-0372-53-213, and bracket P/N 109-0373-02-113 from service and replace with airworthy parts.
(ii) Inspect the vertical fin vibration absorber installation P/N 109-B810-79-101 for hole elongation; for fretting between the plate and the masses and in-between the masses; for fretting on doubler P/N 109-0372-53-213; and the bolts for scratches and corrosion. If there is any hole elongation; fretting between the plate and the masses or in-between the masses; fretting on doubler P/N 109-0372-53-213; or bolts with scratches or corrosion, before further flight, remove the vertical fin vibration absorber installation P/N 109-B810-79-101 from service.
(2) Within 12 months after the effective date of this AD unless already accomplished per paragraph (g)(1)(ii) of this AD, remove the vertical fin vibration absorber installation P/N 109-B810-79-101 from service.
(3) As of the effective date of this AD, do not install vertical fin vibration absorber installation P/N 109-B810-79-101 on any helicopter.
(4) Removing the vertical fin vibration absorber installation P/N 109-B810-79-101 from service, as described in paragraphs (g)(1)(ii) or (2) of this AD provides a terminating action for the 100 hour TIS repetitive inspections required by paragraph (g)(1) of 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
