Q. Let's see...locked onto 3+ satellites? A. Who isn't these days? Many are now locked on to 6+. Q.Selective Availability turned off? A. You know it. Q. If you're able to do simple pre- high school math, do you think a GPS unit could? A. Of course. Q. Is GPS altitude accurate? A. Yes, more so than most barometric solutions. Seriously, think about it...more than 3 birds in view and it has to be pretty damn accurate if you can do trig and know a little about how GPS works :-p -marc On 15/6/03 19:33, "Dave King" wrote: > At 02:05 PM 15/06/03, you wrote: >>> >>> Actually, on a serious note, I have often thought about incorporating a GPS >>> into a RC plane and programming it for a specific flight plan, including >>> takeoff and landing, maintaining specific speeds and such... but the one >>> thing I never investigated is if you can use a GPS to get the current >>> altitude ? >> >> Yes, but the altitude is not very precise. I've seen boats at 1000' above, >> and 600' below sea level, on the same ocean. >> >> You're better off to use barometric or some other means. > > The aviation gps's seem to be bang on for altitude. Flying around in the > mountains in a float plane it nailed every > altitude in the air or on the water. The baro altimeter might be 75ft out > on a known surface while the gps was > within 10' of the published all the time. That was just using a Garmin > handheld with the stock antenna and > 3-5 lock-on's. > > Dave > > -- > http://www.piclist.com hint: To leave the PICList > mailto:piclist-unsubscribe-request@mitvma.mit.edu > -------------------------------------------------- Marc Nicholas Geekythings Inc. C/416.543.4896 UNIX, Database, Security and Networking Consulting -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu