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Installed an uAvionix AV-30

Rick G

1977 Lance P32R-300
Jul 9, 2019
Reaction score
Atlanta, GA
1. Background on why I installed it as opposed to an upgrade
2. Initial thoughts impressions
3. Issues and has anyone had the same problem?
4. Pics

I don't trust Vacuum systems as primary instruments. However, my vacuum system drives my autopilot. The cost of swapping autopilot is a minimum of $7000 for an Aerocruz 100 or $14,000 for a Garmin system (requires a minimum of a G5 panel or better a GI-275). I had to think a lot about my goals. Because the economy has peaked and fuel prices are rising, I am not in a rush to spend 5 figures on a new avionics suite. Also, I'm not sure how long I will stay in this airplane.

I have a working Century IIIc autopilot that is repairable. It's not perfect, but it works good enough for my satisfaction. I'm going to stick with it for a while until there are other options such as Dynon (not currently certified for Lance). Meanwhile, I want something that works as a good backup and possibly replace my primary attitude indicator. The $2000 cost for an AV-30c and ability to self-install is attractive. After all, on a cross country trip I might spend $2000 of fuel. So cost is relative.

The next viable option would be a Garmin Gi-275. If not connected to my autopilot, the installed price would be about $4500. The Gi-275 is better, but essentially serves the same purpose for what I need. An advantage of the Gi-275 would be the upgrade path to a full digital system. But, at a cost of about $8000, and I would still have an analog autopilot.

So, the final decision came down to: a) invest in a bunch of toys that look cool. b) Spend that money on flying a lot this year. We opted to fly more.


I did a partial install with only minimal connections. My plan is to connect the GPS and audio alerts later. I already had an AV-20. I moved the AOT probe from the AV-20 to the AV-30. This cut install time in half. I also had all of the quick connect plumbing done due to the AV-20 installation. Because of this, the pitot/static connections took only about 30 minutes.

The AV-20 comes with a wiring harness. The AV-30 does not. I had to build the connector.

I didn't have enough time to redo the plumbing for the vacuum attitude indicator to move it (it's required for my autopilot). I would need to replace various rubber hoses. Also, I wasn't wanting to make "fully committed" changes yet until I have some experience with the AV-30. So for now it is installed as a backup instrument, replacing the turn-and-slip. However, it is fully functional as an attitude indicator.

Out of the box, the airspeed, VSI, attitude and slip indicator were perfect. No adjustment required. I took a short flight in daylight to verify indications by cross checking with analog instruments.
I have never flown with a digital instrument. But within minutes I found myself using the AV-30 as my primary instrument. I like the consolidated, intuitive view. Everything you need to see is in one instrument as opposed to scanning the six-pack. I still believe in scanning for cross-checking but having everything in one view, to me, reduces work load and fatigue.

I flew with it both in day and night. The AV-30 is bright enough in the daytime, even in direct sunlight. There is no glare. At night I would prefer it to be a bit dimmer (which is probably adjustable). But out of the box it was okay.

Vertical speed: The digital field not display less than 100 fpm change. Above or below 100 fpm it displays in 10' increments. I'm not sure if this is an adjustable setting or not. I would prefer the minimum to be +/-50'. However, I don't see this as any kind of impediment to using it. The analog VSI shows trend and will lead the actual vertical speed. The AV-30 shows actual. The AV-30 also has a trend indicator that has no minimum. It seemed to show approximately the same as the analog VSI. I found the digital VS to be useful for ascent/decent rates and the trend to be more useful for holding altitude in turbulence.

Heading: No lag, but drifts if not slaved. See issues.

AOT: Seems to work.
TAS: Would have been nice, but seems to have same issue as AV-20. It shows 5% high. See issues.

The heading drift - not good. I have a unit with an internal magnetometer. However, in the installation manual it says not to turn this on until pending approval. I think it's better to connect it to the GPS. However, choosing between the AV-30 non -and non-slaved vs. using the wet compass, the AV-30 wins. I'll probably try the internal magnetometer even though it is not officially approved. I can do this because I'm technically using the instrument as a standby.

True airspeed is showing 5% higher than what it should. I have the exact same problem with the AV-20. I don't know if there is a fix for this or not. Anyone know? I will probably contact support Anyway, TAS is not a required instrument. So whatever. I know how to calculate it accurately if I need to. I'll probably change the layout to put something else in the TAS field like maybe AOT.

Was it worth it?
So far, I like it. It does what I wanted it for. I feel safer because I have a full backup. Even in the event of an engine out and power failure this thing will still work for 2 hours. (BTW.. if the engine dies, so does the vacuum). Not that I can glide for 2 hours, but it's good to have that piece of mind. But I have had a power failure in the middle of nowhere. So that 2 hours battery might come in handy someday. I look at the AV-30 as an insurance policy. For about the cost of about 2 years worth of life insurance, I feel more confident that a vacuum failure will not cause me to crash in IFR.




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