Panel Help- AV-30? Other? Nothing?

[skywagon8a]

Pete, that does vary. I think that’s true for CAR 3. Part 23, not so much.

Take a look at the Cub Crafters CC-19-180 type certificate. It calls out “Day/Night Visual Flight Rules(VFR)”.

The CC-18-180 listed Day Visual Flight Rules”. When CC opted to include night VFR, all airplanes had to go back to the factory, to be modified to night VFR.

On the other hand, here’s the pertinent excerpt from the Aviat Husky TC:

Equipment
Part 23 of the Federal Aviation Regulations dated February 1, 1965 as amended by 23-1 thru 23-31 (Normal Category)
The basic required equipment as prescribed in the applicable airworthiness regulations must be installed in the aircraft for certification. In addition, the following items of equipment are required:
1. FAA Approved Airplane Flight Manual
2. Stall Warning indicator.
3. Cylinder head temperature gage.

MTV

Mike, Definitely Part 23 is more strict in it's requirements. The only work I've done with a Part 23 airplane is to install floats or skis which had been previously STCd. The advantages or disadvantages of Part 3 or Part 23 could be a subject of another discussion. You could likely guess my view.

[Cardiff Kook]

Was looking behind panel again today and assessing depth/space. I actually think the crossbar behind the inclinometer may prohibit any instrument of much depth from replacing it so punching another hole might be the only option if I go that route.

[Cardiff Kook]

OP update.

I ended up installing the av-30. I think it was the right call for my situation. I appreciate the diverse opinions on the matter. Neat little unit.

For those of you who have one with the magnetometer- can someone explain the function aid setting “mag 1” vs “mag 2.”

I saw in document that mag 1 adjusts DG and mag2 DG and “ahrs algorithm”- not sure what that means. I get it probably reduces drift on the HI? Does it still need to be set to wet compass? Will the magnetic interference in my panel that will mess with the magnetometer?

Thanks.

[bcone1381]

Kook;

I have no experience with the AV-30, but have with other installations. Generally a remote Magnetometer gives the DG its compass heading information. No drift is experienced with a Magnetometer if set up right. Ones I've used magically align the DG and will stay in alignment the entire flight. The Magnetometer is installed on the airframe in an area that has no magnetic distortions and wires cary the signal. So mine is installed in out near the wing tip 3 feet away from any large iron. Moving iron can be especially bothersome to a magnetometer, like an aileron bell crank or a steel fight control able.

I suspect (key word is suspect) Mag1 is the setting used if no magnetometer is installed, and Mag2 is going to give the DG compass indication information from the Magnetometer + AHRS.

AHRS stands for Attitude heading reference system. It's electronics that do the job of gyros. Sometimes an AHRS is a box that sends signals to a Attitude or Heading indicator mounted on the instrument panel. An AV-30 has the AHRS built into its indicator. Amazing to me.

[wireweinie]

The AV-30's magnetometer is optional and is built in (i.e. not capable of being mounted remotely). This means it WILL be subject to magnetic interference in the panel area. And since it's mounted inside of a ferrous tube cage, you will need to do some checking to see if it will point accurately. The most accurate check would be using a compass, outside of the aircraft, to line up the fuselage center line with 0º/180º and 90º/270º while the tail is raised to flight level position.

Web

[frequent_flyer]

I suspect (key word is suspect) Mag1 is the setting used if no magnetometer is installed, and Mag2 is going to give the DG compass indication information from the Magnetometer + AHRS.

It seems to be documented reasonably well in the installation manual. My understanding is that the magnetometer is an optional device internal to the AV-30. The magnetometer usage options are defined in para 14.1.7 AID Mode.

Value AHRS Aiding Source
NONE None used
MAG1 Internal magnetometer provides correction data to DG – Do Not Enable unless authorized by follow on approval
MAG2 Internal magnetometer provides correction data to DG and aiding to core AHRS algorithm – Do Not Enable unless authorized by follow-on approval

I agree with your summary of how the magnetometer could be used for "aiding". Perhaps of interest that the AV-30 without magnetometer option will use external GPS for AHRS aiding but that option doesn't seem to be available if the optional magnetometer is fitted.

I don't know what "follow-on approval" is needed. Perhaps the firmware to support these options is not available yet. The internal magnetometer seems to be a very recently added option.

It's impressive how far MEMS based AHRS have come. I added the optional AHRS module to my Stratux ADS-B receiver and it provides a reasonably useful attitude indicator for about $20. (No, I would not use it in IMC.)

[mvivion]

Kook,

I suspect that the Mag 1, Mag 2 reference comes from the AV-30's capability of being connected to a GPS input to provide DG input. Otherwise, the ADHRS (the "brain" for the attitude instrument) updates the magnetometer, once set to Compass.

Maybe. Give Rebekah at uAvionix tech support a call. She's really sharp on these things.

MTV

[Cardiff Kook]

I spoke with Rebekah at uavionix. Very nice.

She said the answer is very complicated the engineers explain it in engineer talk which is difficult to understand.

She said the just of it as she understands it:
1. Mag 1- relies on the internal magnetometer a little
2. Mag 2- Relies on the internal magnetometer alot

I appreciated her dumbing it down for me.

[frequent_flyer]

I appreciated her dumbing it down for me.

Did she explain what "follow-on approval" was required before selecting either option?

[Cardiff Kook]

Take this part with a grain of salt because I wans't listening as well here: she said it is not legal to accept either option at this time- even if you can- for certified aircraft because of something that has to do with FAA approval? Again, grain of salt, but apparently the hardware is legal and the software is legal but the process of making the selection is not yet approved?

Again- don't take that as gospel. It seemed rather complicated.

[coxcub]

Web - Re post #85

I have been in contact with Uavionix about a remote magnetometer for the AV30 after reading this

https://uavionix.com/uavionix-announ...anel-displays/

I wanted to know if and when one would be certfied - the reply was this

"certified by FAA any day now so good for an N reg if you have it. For a G reg we are talking some months"

Frank

[wireweinie]

The AV-30's magnetometer is optional and is built in (i.e. not capable of being mounted remotely). This means it WILL be subject to magnetic interference in the panel area. And since it's mounted inside of a ferrous tube cage, you will need to do some checking to see if it will point accurately. The most accurate check would be using a compass, outside of the aircraft, to line up the fuselage center line with 0º/180º and 90º/270º while the tail is raised to flight level position.

Web

Thanks Frank. That's good news from µAvionix. My opinion is that all aircraft should use a remote mount flux gate for any magnetic instruments. The remote mount allows you to find the best place, with respect to magnetic interference, to mount the gate, in order to get the best accuracy from the mag instruments. With switches, breakers, bus bars, and most of the wiring in or passing through the panel area, that's about the worst place to mount any kind of compass. Most of the older Cubs up here used a remote compass with the flux gate mounted out near a wing tip (remember the larger square inspection panel? That was for the flux gate). Those were about the only magnetic instruments that I found to be accurate. The flux gate was away from heavy wiring, charging system, and ferrous metals, which improves it's function.

Web

[skywagon8a]

And when you run the power to that remote fluxgate, run the ground back twisted around the power several feet to eliminate any inductance from the power wire.

[wireweinie]

Or use shielded wire, with the shield as the ground.

Web

[bcone1381]

And when you run the power to that remote fluxgate, run the ground back twisted around the power several feet to eliminate any inductance from the power wire.

I'd like to add to this good advice....Also try to run the magnetometer wires away from your strobe/Nav light wires. For example, I ran my Nav/Strobe wiring along the rear spar and the Magnetometer wiring along the front spar. The lower the amp draw the less the Nav/Strobe wiring can will influence stuff, so therefor, LED lights will be less of an influencer than a traditional neon bulb strobe set up. Garmin wanted a 3' separation.

[wireweinie]

A basic electricity point: magnetism is produced by the current flow in a wire, NOT by the voltage applied. I know, I know, it takes voltage to push amps. That is correct. But until there is a flow of current there will be no magnetic field formed around the wire. For example if you routed a heavy wire near a compass and opened the breaker on it, even if you applied eleventy jillion volts to that wire, it would not affect the compass. As soon as you closed the breaker and current started to flow, a magnetic field will form around the length of the wire. The strength of the field will be proportional to the amount of current. So, as bcone points out above, old school incandescent nav lights pull lots of current compared to LED navs, therefore, you will need more separation between the compass and incandescent wiring than you would when using LED lights. Web