Enigma Altitude

[rastley]

I've just had a Zenith 601XL delivered to me with an Enigma EFIS

The ferry pilot said it was showing some wonky airspeed readings.

Upon investigation it was a blocked pitot tube. While I had the tube off and the panel apart I figured I'd do a pitot and static test.

I had to pull the EFIS out of the panel but the builder didn't leave any service loops. As such I broke off the nipples for pitot and static.
The AOA ports aren't being used so I opened the back and swapped out the two pairs of sensor (they had the same part number). Put everything back together to test.

When slight pressure is applied to the pitot side the airspeed increases which is to be expected. Airspeed stays within 10 knots for a minute.

When applying a vacuum to the static side the altitude doesn't change but the airspeed increases.

I cant figure out or understand what could be causing this.

Does the Enigma source altitude data from somewhere else?

Any ideas?

Cheers
Rich

[sparxfly]

Airspeed increasing as vacuum applied to the static makes sense- you are creating a positive differential pitot over static.
That also indicates the static sensor is working to some degree, as it is responding to pressure changes.
Try calibrating your altimteter channel.

[rastley]

Thank you. Yes, I managed to test that this morning.
I'm making progress.