Fluctuating TAS, Density altitude while flying

[jethound]

Dynon,
Although it has happen a couple times when flying and again today I would like to see what you think
While flying at a constant altitude doing about 185 TAS all the sudden the airspeed is flu coating from about 150 to the 185 and changing speeds very rapidly like every nano second. And the DA is changing altitudes just as fast.

I thought perhaps a bug got in the pitot tube.. I turned on the Pitot heat. For a couple minutes and when I glanced back down whether it was due to the pitot heat or not the speed was constant and the DA for most part was stable.

Any Ideas.
Thanks
Jack Hunt

 

[lgabriel]

Which airspeed fluctuates - IAS or TAS?

If TAS...did you notice any fluctuations with your OAT? I suggest something is up with your OAT probe or wiring...which (as far as I know) is the only common link between DA and TAS.

 

[jethound]

TAS fluctuated one temp probe is located under right wing the other probe is on the bottom of the aft fuselage about 1/2 way between wings and horizontal
Jack

 

[Dynon]

If IAS and the altitude tape are solid, but the TAS and density altitude are moving, then it's likely your OAT that's actually fluctuating (intermittent connection, probe failing, etc). If you export a data log you might be able to see it after the fact when you open it in excel.

 

[jethound]

I will check the connections out.
Jack