All valid points scott, but the Borgelt device rounds the barometric altitude to steps of 100ft and in my experience GPS altitude is more accurate then this... Lets say you are at FL99 according to Borgelt and FL100 is the airspace, you don't know if you are 1m below it or 99m. This value doesn't seem that usefull to me... Maybe we have someone on this mailing list with contacts to Borgelt, might be possible for them to change the protocol and output the real barometric altitude without rounding...
Turbo Am 05.10.2010 12:32, schrieb Scott Penrose: > On 05/10/2010, at 7:21 PM, Tobias Bieniek wrote: > >> Why do you think that the _rounded_ baro altitude would be more >> accurate then the GPS height?! > GPS vertical is far less accurate than horizontal. I can't remember the > numbers, but it might be 10 times less accurate. > Now if you are out by 10m horizontal, that is nothing (now, depending on > location on the earth, this is somewhat improved, and I believe is now 3m) > but vertically 30 or 100m is a lot. > > There are lots of threads on the net about using combination of GPS and > Barometric. Some even talk about combinations. Assuming you know your ground > pressure, the barometric pressure is more accurate. > > Ah, I just found an article that said it is only 3 times the horizontal > error, but that they are only right 90% of the time, and that 10% they can be > out by 100s of feet - which is no where near as bad as I thought. > > Scott > ------------------------------------------------------------------------------ > Beautiful is writing same markup. Internet Explorer 9 supports > standards for HTML5, CSS3, SVG 1.1, ECMAScript5, and DOM L2& L3. > Spend less time writing and rewriting code and more time creating great > experiences on the web. Be a part of the beta today. > http://p.sf.net/sfu/beautyoftheweb > _______________________________________________ > Xcsoar-user mailing list > Xcsoar-user@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/xcsoar-user > ------------------------------------------------------------------------------ Beautiful is writing same markup. Internet Explorer 9 supports standards for HTML5, CSS3, SVG 1.1, ECMAScript5, and DOM L2 & L3. Spend less time writing and rewriting code and more time creating great experiences on the web. Be a part of the beta today. http://p.sf.net/sfu/beautyoftheweb _______________________________________________ Xcsoar-user mailing list Xcsoar-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/xcsoar-user
