You May Not Be In Compliance With Airworthiness Directive 2010-07-02

May 2014

There are two steps to Airworthiness Directive (AD) 2010-07-02. You are not in compliance unless you have completed both.

Many operators believe they are in compliance with this AD. However they find out differently when they send the units in for maintenance. Duncan Aviation avionics technicians continue to see Primus II RNZ units arrive that only meet half the AD requirements.

Step One – Part Number Conversion

AD 2010-07-02 addresses erroneous localizer and glideslope indications that have occurred on certain aircraft equipped with the Honeywell Primus II with part numbers 7510100 –xxx.

The AD affects all of the following NV-850 navigation modules with part number 7510134-xxx (part of the RNZ) with or without Mod T.

Basically, AD 2010-07-02 requires part numbers to be converted from NV-850 7510134-8XX & 9XX to 7510134-6XX & 7XX with Mod T installed. (Mod T is discussed in Step Two).

The AD is a simple process that requires a microwave pad for the NV-850 and installation of new Product, ID and Mod plates to the RNZ and NV-850 for future quick reference that the AD has been complied with.

You can receive partial warranty credit for this AD. For more information about the Honeywell warranty, contact aDuncan Aviation Avionics Instruments Tech Rep.

Step Two – Mod T Installation

You are not in compliance with this AD until the second step is performed. Once the above part numbers have been converted, the nav module needs to have Mod T installed.

If you have a unit installed with one of the above part numbers, check the mod status on the bottom of the data tag. On a NV-850 unit, if the block “T” is blackened out, then the unit is in compliance. On an RNZ-850, if the "Mod AS" is marked off, the unit is in compliance. If the “T” is still visible, the unit does not have mod “T” installed and requires modification to comply with this AD.

Don’t Delay

Aircraft that have NOT complied run the risk of approaching a landing at an unsafe altitude and alignment, which could result in impact with an obstacle or terrain.

Contact a Duncan Aviation Component Solutions Avionics Tech Rep for more information.