Airspeed calibration

[Tuiliere]

Hello,
I discover during a windless flight that my Air Speed Indicator was a little bit optimist compared with my GPS speed. I would like to correct the Skyview Air Speed but I don't see how to do that in the installation manual. Can you help me ?
Thank you
Sylvain

 

[Dynon]

The airspeed on SkyView can't be adjusted for position error. You'll need to look at pitot and/or static position error, which is most likely the source of the discrepancy (I'd say 98% of the ADAHRS/EFISes we see back here for "airspeed accuracy" issues in fact work properly, down to the knot). Almost always it's the pitot/static system isn't quite generating the right pressures.

 

[Pilots8000]

Or... your TAS will read too high if your air temperature sensor is reading too high (possibly in your engine exhaust airflow).  For example, at 3000 feet and 150 KCAS, a +10 deg C error in OAT will cause the TAS to indicate about 3 knots faster than the correct TAS.

 

[paul330]

Also bear in mind that the probe technically measures Total Air Temperature not OAT. This will be slightly higher due to the kinetic energy of the aircraft. I guess the effect is small on a GA aircraft but could account for a couple of knots.

 

[Highlander1]

My airspeed was indicating consistently 10 knots higher than my

 

[Highlander1]

My airspeed was consistently 10 knots higher than the GPS was showing. I had my static system vented behind the panel. Since this wasn't any problem I let it go for a couple of years until I couldn't stand it any longer. Then I installed a static vent on either side of the fuselage and tee'd them together close to the ADAHRS. Now things are looking as they should.

Gil T

 

[rv12roger]

What is the experience of the RV12 crowd. Pitot in the nose cone and statics on both sides of the tail cone. I would it is pretty optimal.