Airworthiness Directive · Amendment 39-11508 · Pilatus Aircraft Ltd. Model PC-7 Airplanes
Pilatus Aircraft Ltd. Model PC-7 Airplanes
Model PC-7 airplanes, all manufacturer serial numbers (MSN) up to and including MSN 614, certificated in any category.
This amendment supersedes Airworthiness Directive (AD) 98-08- 07, which currently requires replacing the rudder and elevator pivot arms with parts of improved design on certain Pilatus Aircraft Ltd. (Pilatus) Model PC-7 airplanes. This AD requires replacing the rudder and elevator pivot arms with parts that have been improved since issuance of AD 98-08-07. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. The actions specified by this AD are intended to prevent failure of the elevator and rudder caused by fatigue cracking of the pivot arms, which could result in reduced airplane controllability and possible loss of control of the airplane.
Required as indicated in the body of this AD, unless already accomplished.
To prevent fatigue failure of the elevator and rudder trim tab pivot arms because of cracks, which could result in the loss of airplane control, accomplish the following:
(a) Within the next 100 hours time-in-service (TIS) after the effective date of this AD, replace the rudder and elevator pivot arms with parts of improved design (or FAA-approved equivalent part numbers), as specified in and in accordance with Pilatus Service Bulletin No. 55-003, dated July 7, 1999. The part numbers of the improved design pivot arms are reflected in the following chart:
| per AD 98-08-07 | ||
|---|---|---|
| Pivot arm, inner elevator | 113.50.07.108 | 113.50.07.108 |
(green paint).
| Pivot arm, outer elevator | 113.50.07.109 | 113.50.07.109 |
(green paint).
| Pivot arm, upper rudder | 113.40.07.084 | 113.40.07.084 |
(green paint).
| Pivot arm, lower rudder | 113.40.07.083 | 113.40.07.083 |
(green paint).
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
