ASI and Artificial horizon not working

[Jenson]

We have just installed a D180 in a CSTW and have two main problems.

1. The ASI failed to show anything other than 0. The altimeter and VSI seemed to work fine as did the backup ASI which was t’ed off the same lines. The only point we were not sure about was the AOA port on the D180, this had the red plastic plug left in as the AOA pitot was not fitted.

2. The Artificial horizon appeared to be slow in responding (the VSI an Altimeter worked fine). And whilst in a constant bank of 20 degrees (circling) within less than 60 seconds the artificial horizon slowly changed from showing a 20 degree bank to indicating we were flying straight and level. On the ground with the unit removed the artificial horizon seemed to respond fine to being tilted.

Any help would be appreciated.

 

[dynonsupport]

The Dynon EFIS units require airspeed to act properly in flight, so your horizon problem is tied to your airspeed problem. What you describe for the horizon is what we expect with no airspeed.

As for airspeed, the easiest thing to do is probably pull the unit from the panel, and put pressure on the airspeed (pitot) port and see if it responds. If it does, it is tubing or some other issue, if it doesn't then the EFIS is at fault.

It's really easy to put pressure on the port- all you need is your finger. When looking at the back of the EFIS, place your finger over the center port so that it makes a good seal with the brass part. Press your finger hard against this port, and you should be able to get 100-200 knots of speed on the EFIS.

If you do this and just can't get any airspeed, it looks like we'll need to see the D-180 at the factory and look it over. If you do get airspeed, then make sure your plumbing isn't kinked and that the pitot line goes to the proper port on the D-180.