2004-08-16 NARCO AVIONICS INC. AT150 TRANSPONDERS: Amendment 39-13586. Docket No. 2002-NE-32-AD.

Airworthiness Directives; NARCO Avionics Inc. AT150 Transponders

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

SUMMARY: The FAA is adopting a new airworthiness directive (AD) for certain serial numbers (SNs) of NARCO Avionics Inc. AT150 transponders. This AD requires modification to the transponder by adding a resistor and transistor to the circuit board. This AD results from reports of AT150 transponders not recognizing and responding properly to Mode S interrogations from Mode S ground stations and Traffic Alert and Collision Avoidance System (TCAS-II) airborne equipment. We are issuing this AD to prevent loss of aircraft airspace separation and the possibility of mid-air collision.

DATES: This AD becomes effective June 1, 2004.

Applicability
   (c)    This AD applies to NARCO Avionics Inc. AT150 transponders with "Chassis Level A", serial numbers (SNs) 10000 through 12598 inclusive.

Unsafe Condition
(d)    This AD results from reports of AT150 transponders not recognizing and responding properly to Mode S interrogations from Mode S ground stations and Traffic Alert and Collision Avoidance System (TCAS-II) airborne equipment. The actions specified in this AD are intended to prevent loss of aircraft airspace separation and the possibility of mid-air collision.