Airworthiness Directives; Gulfstream Aerospace LP Model 1125 Westwind Astra Series Airplanes

This amendment supersedes an existing airworthiness directive (AD), applicable to certain Gulfstream Aerospace LP Model 1125 Westwind Astra series airplanes, that currently requires revising the airplane flight manual (AFM) to provide the flight crew with operational guidance under certain failure conditions and a limitation not to engage the long-range navigation system during takeoff, approach, or landing. This amendment requires replacing the low-voltage sensing relays with higher-accuracy relays, and replacing the circuit breakers of the directional gyros with circuit breakers with lower amps. After the replacements have been accomplished, this amendment also requires inserting a new temporary revision in the Limitations section of the AFM, or removing the revision to the AFM required by the previous AD. The actions specified by this AD are intended to prevent the loss of primary attitude and directional gyros, which relate position information to the flight crew. This action is intended to address the identified unsafe condition.