For anyone having IAS or TAS problems;
The web site below is easy to use and seems to be exceptionally accurate. I have used it with many airplanes to check the accurracy of the air speed indicators. You will need a GPS or a LORAN. I use my hand held GPS.
REA Computing
Sorry I don't know an easier way to bring it up.
Computing True Air Speed
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TAS/IAS Software
If there is an interest I have a utility program for Windows that calculates true and indicated airspeed from GPS groundspeeds. I have used it to calibrate my airspeed indicator and got good results from it.
Phil
Phil
- flyguy
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BOO BOO
I went there yesterday but didn't go to the "APPLETS" link. (SUMTIMES HESA JES DUMMER N DIRT_)
Now is this really a way to "calibrate an airspeed indicator? I have some misgivings about the procedure and time spent doing all those gyrations. With 'SO MANY' variables to consider what is the "real" benefit. GPS reported ground speeds vary between different units. Maybe not much but a variable nevertheless. Magnetic variation way out west does another curious alteration to the "Cardinal Heading" requirement. Compasses act goofy way out in them thar deserts! A GPS heading/track will show something different than that ole whiskey compass does. Next variable, I can do straight and level but sometimes not at the same time!
My suggestion( FWIW) "Go to a good avionics shop and do a certified calibration" - then spend the flying time behind that "SUPER ACCURATE" airspeed indicator coming to Louisiana to see me! I'll feed you some fried turkey or boudin!
http://www.satansbreath.com/recipes/nav ... boudin.htm
Now is this really a way to "calibrate an airspeed indicator? I have some misgivings about the procedure and time spent doing all those gyrations. With 'SO MANY' variables to consider what is the "real" benefit. GPS reported ground speeds vary between different units. Maybe not much but a variable nevertheless. Magnetic variation way out west does another curious alteration to the "Cardinal Heading" requirement. Compasses act goofy way out in them thar deserts! A GPS heading/track will show something different than that ole whiskey compass does. Next variable, I can do straight and level but sometimes not at the same time!

My suggestion( FWIW) "Go to a good avionics shop and do a certified calibration" - then spend the flying time behind that "SUPER ACCURATE" airspeed indicator coming to Louisiana to see me! I'll feed you some fried turkey or boudin!
http://www.satansbreath.com/recipes/nav ... boudin.htm
OLE GAR SEZ - 4 Boats, 4 Planes, 4 houses. I've got to quit collecting!
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