GPS glide ratio calculations

hi,

i posted a message on this board last year - see below - asking advice for a GPS
to record the "flights" i make with my wingsuit from aircraft / cliffs.

I purchased an Garmin etrex vista in the end and am very satisfied with the results.

If anyone is interested in seeing the resulting data then feel free to contact me.

Blue skies,

James


1 messaggio/i nella sequenzaDa:james )
Oggetto:GPS glide ratio calculations *
View this article onlyNewsgroups:rec.aviation.soaring
Data:2003-09-03 05:45:13 PST

Hi,

I am looking into buying a small compact GPS unit to measure the
flight performance of an un-powered aircraft (of sorts - more later).

Can anyone recommend particular brands/models that are particularly
suited
to my application?

2 units I have found so far a

-Magellan Free Flyer
-eTrex vista

comments or opinions on these models please?

I am interested in obtaining accurate position/altitude data so that I
can
find (preferably from the GPS itself, rather than post a PC download)

- horizontal speed
- vertical speed
- glide ratio
- flight time

Is it also true to say that I will be able to display the flight over
a 3D terrain map on a PC using the correct 3rd party software? (e.g.
Oziexplorer3D) - just for the novelty!

My aircraft is well, err, me (not a troll!) - I practice a form of
parachuting which is called BASE jumping. To extend the length of my
freefall I wear a special "bird suit" that gives me a glide angle
of 2:1 (or more as my technique improves and hence why I want to
measure it).

For those who are interested - www.bird-man.com - the website of my
suit manufacturer.

This is one of the fastest developing areas of skydiving / BASE
jumping. There are people making 2+ minute flights (3:1+) jumping from
various cliffs around the world.

Before you ask - no, you would be mad to try and land one! The best
flyers are getting the vertical speed down to below 50km/h but the
horizontal speed is over 160km/h!

Thank you for your time,

James