AD NUMBER: 2006-22-05
MANUFACTURER: Integrated Navigation Unit
SUBJECT: Airworthiness Directive 2006-22-05
SUMMARY: The FAA is superseding an existing airworthiness directive (AD), which applies to various aircraft equipped with certain Honeywell Primus II RNZ-850( )/-851( ) integrated navigation units (INUs). That AD, as one alternative for compliance, provides for a one-time inspection to determine whether a certain modification has been installed on the Honeywell Primus II NV-850 navigation receiver module (NRM), which is part of the INU. In lieu of accomplishing this inspection, and for aircraft found to have an affected NRM, the existing AD provides for revising the aircraft flight manual to include new limitations for instrument landing system approaches. This new AD requires inspecting to determine whether certain modifications have been done on the NRM; and doing related investigative, corrective, and other specified actions, as applicable; as well as further modifications to address additional anomalies. This AD results from reports indicating that erroneous glideslope indications have occurred on certain aircraft equipped with the subject INUs. We are issuing this AD to ensure that the flightcrew has an accurate glideslope deviation indication. An erroneous glideslope deviation indication could lead to the aircraft making an approach off the glideslope, which could result in impact with an obstacle or terrain.

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