(2008) Service Advisory 0841 Rev A: GPS 400W/GNC 420W/GNS 430W/GPS 500W/GNS 530W VNAV Advisories

AFFECTED PRODUCTS

All 400W / 500W Series Units with software Version 3.11 or earlier

DESCRIPTION

Garmin has identified an issue with the operation of 400W / 500W Series Units and VNAV guidance:

When the operator performs a “direct-to” operation to one of the waypoints in the active flight plan and then sets up a vertical navigation profile (VNAV) to any point in the flight plan, the unit may not generate VNAV guidance or it may generate inaccurate VNAV guidance messages.

The problem only occurs when both:

• The operator performs a direct-to operation to a waypoint in the active flight plan 
• A VNAV profile is set up during the direct-to leg 

The problem may occur when flying direct-to a waypoint on any portion of the flight plan (departure, enroute, or approach). 

RESOLUTION 

This issue will be corrected in a future software release. Pilots are to be aware that VNAV descent alert messages and vertical speed required (VSR) are for advisory purposes only and should not be used to maintain terrain or ATC clearances. Compliance with terrain and ATC clearances is the sole responsibility of the pilot.