AD NUMBER: 2006-16-18R1
MANUFACTURER: Terrain Awareness Warning System (TAWS)
SUBJECT: Airworthiness Directive 2006-16-18 R1
SUMMARY: The FAA is revising an existing airworthiness directive (AD) that applies to Sandel Avionics Incorporated Model ST3400 TAWS/RMI units as described above. The existing AD currently requires installing a warning placard on the TAWS/RMI and revising the Limitations section of theairplane flight manual (AFM). The existing AD also requires installing upgraded software in the TAWS/RMI.

This new AD allows installing later revisions of the software described in the existing AD. This AD results from a report that an in-flight bearing error occurred in a Model ST3400TAWS/ RMI configured to receive bearing information from a very high frequency omnidirectional range (VOR) receiver interface via a composite video signal, due to a combination of input signal fault and software error.

We are issuing this AD to prevent a bearing error, which could lead to an airplane departing from its scheduled flight path, which could result in a reduction in separationfrom, and a possible collision with, other aircraft or terrain.

FMI: www.faa.gov/regulations_policies/airworthiness_directives/