My club’s Cirrus SR20 has an EXP5000. The knob on the right side bottom of the PFD, which changes values for the Hdg Bug, Alt Bug, VSI bug and Baro Set is no longer working. Twisting it in any of those modes does nothing.
The only thing that works with that knob is that pressing it will sync the heading bug with the current heading…
With that IFR flights are forbidden on the aircraft.
The club member in charge of maintenance says our avionics shop (I don’t know who this is) said he needs to change the entire PFD at a cost of approx. 15,000 EUR.
I proposed to look into it.
Why does one need HDG/ALT/VSI bugs to be “legal IFR”? I don’t recall anything as such in nco.ide.a.125, so where that come from? the SR20 PFD manual? or MEL?
You will need BaroSet working (even for VFR) unless you are using your backup altimeter for that job, I am talking about what you need to legally fly IFR, it should not be an issue to fly IFR in VMC with that one? for IFR in IMC the list of convenience items is very subjective…
Just open it up and either replace or fix the knob. My car had a similar issue on the volume knob and they wanted to exchange the entire center module at 4 digits. Got the thing out, did unsolder the rotary encoder, unfortunately no usable part number on it so had to fix the existing one. Usually there is dirt resulting from friction when turning those things forming inside. Did open it, clean it, put it back together and happy motoring ever since. But you will need someone familiar with eletronics to do such work.
But, seriously, I would find somebody who is good with mechanical stuff and just repair it. It is probably an off the shelf part (the last company making their own knobs was the great American Tektronix and what happened to them is a sad story) and can be found on e.g. mouser.com.
It may not be the knob that’s broken. It may be the linkage behind it, or the potentiometer/switch it is operating. This needs an “electronics guy” and of course you do it off the books The linkages are easy to damage by bumping against them.
I have a Cirrus 22 with the Avidyne R9 which is really fabulous, but it has had a few issues with failures. With prior warning this might happen I took out a warranty program with Avidyne directly. From memory this was around 8k usd for three years, all RTB, so I cover shipping both in and outbound. So far I am very much ahead so if your system is anywhere like ten years old or more then I would absolutely recommend the warranty.
Thank you all for your hints, including those of Alexis who isn’t registered on the forum but found me on internet and emailed me.
I’ll discuss all options with the club’s administrators. One option would be to spend the initial proposal $15k but get a complete upgrade with WASS and a digital autopilot.
I will keep you posted.
I reckon an hour to repair it
The DFC 100 autopilot is superb. I replaced my Stec 55 and it was night and day.