GPS anomalies

Flyingmac100 · Post by **Flyingmac100** » Mon Sep 07, 2009 12:39 pm

I have a Lowrance Airmap 600c GPS which shows the runway at Dundee to be surrounded by water.
Having landed there several times without floats, I know that this is not the case. Does anyone have any thoughts on how to correct this and a number of other less major errors?.

Nigel Ramsay · Post by **Nigel Ramsay** » Mon Sep 07, 2009 3:38 pm

...... never treat it as a primary navaid! (I'm sure you don't of course). I once navigated to Holland (I can't remember the actual airfield) before GPS was available, dead reckoning and quite pleased with the job, using a new Jeppeson map. I found myslef flying the wrong way on the downwind leg of a busy fly-in! Upon landing I was summoned to the tower for a b******ing but amazed the controllers by showing them my new Jeppeson chart which showed the airfield on the opposite side of a major motorway to it's actual position!

GPS can and will catch some out if they don't use a chart to confirm their position. I expect you'll be thanked for telling them the graphics are wrong, just like I was when I phoned Jeppeson, something like "Oh, ok, we'll make a note of that and put it right at the next edition, thanks for calling" At least the airfield was in the right place

malcolm frost · Post by **malcolm frost** » Mon Sep 14, 2009 4:16 pm

The GPS is not the problem, what is is the database. If you are going to check against a chart, it would have to be made by a different manufacturer from the GPS database provider.
In Airmaps case the database is produced by Jeppesen, and the way charts are produced these days any errors in one would be replicated in the other.

Flyingmac100 · Post by **Flyingmac100** » Fri Sep 18, 2009 5:35 pm

Cheers Malcolm. Guess I'll just have to remember not to get my feet wet by attempting to fly a GPS approach into Dundee in IMC.