Quite a few over at the Cessna 150/2 group are singing the praises of the AC30. I've extracted some comments that seem relevant - keeping it to the last six months as the units get into the field and used.
Though they have been a bit twitchy to get set up correctly. uAvionix sent this process to some members and it seems to make a difference:
uAvionix Support wrote:Startup:
-Battery master applied while stationary on a level surface in front of the hangar.
-The AV-30's are left running for three minutes completely stationary. Nothing else in the aircraft is powered other than the electric turn coordinator and intercom system.
-Shut down master
-Apply battery master and let the aircraft sit stationary for 5 minutes until engine start.
-Engine Start
Shutdown:
-Aircraft is positioned in the middle of the taxiway on a straight and level surface
-All electrical equipment shut down in the aircraft other than the two AV-30's and the electric turn coordinator.
-Alternator Off
-Mixture pull, propeller comes to a full resting stop.
-Mags Off
-Wait 30 seconds, Battery master shut down.
We are currently doing some flight tests and hope to have a solution for you, this current solution would be temporary.
Because your units have gotten a bad calibration, we might look at bringing in your unit and sending some other ones. Let us know if you see a difference in applying these steps a few times.
Though a few reported multiple calibration attempts before they would work correctly.
There have been problems with precession on the DG heading - which uAvionix say has been solved with a firmware upgrade and at least one member there sent theirs back for a screen that went dim.
Clean power with no ripples or spikes seems to be important.
It MUST be installed level and square to the aircraft axes to deliver good heading information.
In the overall scheme of things though - folks seem happy. They have been the early adopters and survived the experience.
Here a selection of comments:
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DonB
Make sure you system is wired in accordance with the Notes in the wiring instruction. Pay close attention to the shields and keeping all the unshielded wire connections inside the D-Subs. You might not think it makes a difference but it really does.
Mike Brennan
Well I will say that aside from this problem (DG drifting) which I am hopeful and mildly confident will get fixed, I am super happy with the two units I purchased and had installed. All the other features work great and the the removal of the vacuum system not only saved some weight but odds were I would experience a failure of the system in the not to distant future. They look good, are easy to read and are interchangeable if necessary. Pricewise I think they are a winner. Just a few growing pains for being an early adopter!
A key feature of the AV-30 is the internal DG, which would allow you to replace both the attitude indicator and directional gyro in a vacuum airplane. Overall it worked well, remaining accurate for 20-30 minutes at a time. uAvionix says a software update readied since my unit was built improves that performance. And while this unit didn’t prove as steady as a system with a magnetometer, which constantly corrects itself, it’s worlds ahead of your typical vacuum gyro. Remember how bad those could be? One possibly important distinction here: The AV-30 does not have a dedicated rate-of-turn indicator, which would be an issue for Experimentals whose operating limitations say they can fly IFR as long as they’re equipped in accordance with FAR 91.205; that FAR explicitly requires a rate-of-turn indicator. In this case, you’d need to keep your old turn coordinator alive to be strictly legal, while the other instrument-hole EFISes we’re familiar with do include the rate-of-turn feature.