AD FAA-2009-0699

We are clarifying information contained in Airworthiness Directive (AD) 2009-21-08, which applies to PIAGGIO AERO INDUSTRIES S.p.A. (Piaggio) Model PIAGGIO P-180 airplanes. AD 2009-21-08 currently requires repetitive functional tests of the manifold system and replacement of any system that does not pass the functional tests (i.e., movement of the steering system). The language in AD 2009-21-08 incorrectly references not passing the functional tests as "movement of the manifold," and it should read "movement of the steering system" as specified in the service bulletin. The notice of proposed rulemaking (NPRM) referenced it as specified in the service bulletin. This document incorporates the intent of the action as already proposed in the NPRM. We are issuing this AD to prevent a potentially dangerous veer along the runway. The steering system must be in the `off' position during landing and takeoff (in this case when airspeed is higher than 60 knots) according to the aircraft flight manual limitations.