Electric backup AI

[MooneyBob]

My turn coordinator died. I'd like to get new electric backup AI, probably RCA26. 

1. Do I still have to have turn coordinator legally? The ball will be attached to the AI. 

2. What is the panel tilt on my 1977 M20J? it is either 0 or 8 degrees?

Any experience with the unit?

Thanks. 

 

[smwash02]

1) No, I have the same AI as you are looking to get as my primary with the ball.

2) It depends. I'm pretty sure 77s are all 0 since there isn't a bend, but hopefully someone else can confirm. I know on my '66C the top is 0 and I have the bottom written down somewhere, but have forgotten.

 

[MB65E]

I would look at the solid state gyro from RCA. It's probably close to the same price as a new mechanical gyro. RCA-2600-3. You should have 0-tilt. 

 

This is what I would do when my current one rolls over.

http://www.aircraftspruce.com/catalog/inpages/rca2600-3.php

 

-Matt

[ArtVandelay]

I assume you don't have a Stec AP, otherwise you'll have to repair it, Stec uses the TC.

[ChrisH]

If you go solid state, why not go all the way with http://www.aircraftspruce.com/catalog/inpages/sai340-11-12817.php.

If for nothing else, the backup battery.

[MooneyBob]

4 hours ago, MB65E said:

I would look at the solid state gyro from RCA. It's probably close to the same price as a new mechanical gyro. RCA-2600-3. You should have 0-tilt. 

 

This is what I would do when my current one rolls over.

http://www.aircraftspruce.com/catalog/inpages/rca2600-3.php

 

-Matt

That's what I meant. I just posted wrong pic. 

[MooneyBob]

3 hours ago, ChrisH said:

If you go solid state, why not go all the way with http://www.aircraftspruce.com/catalog/inpages/sai340-11-12817.php.

If for nothing else, the backup battery.

Definitely option to consider. I have to ask my avionics guy about installation time and cost. 

[tls pilot]

6 hours ago, MooneyBob said:

My turn coordinator died. I'd like to get new electric backup AI, probably RCA26. 

1. Do I still have to have turn coordinator legally? The ball will be attached to the AI. 

2. What is the panel tilt on my 1977 M20J? it is either 0 or 8 degrees?

Any experience with the unit?

Thanks. 

 

most likely O tilt

I changed my old one to a new digital

simple easy install

call he folks at RC Allen about a trade up with your core

[FlyDave]

I got the RCA 2600-3 earlier this year and I find it easier to fly with than the King KI-256. During an IPC earlier this year the instructor failed the AP, 530 and KI-256.  I was left with a King KX-155 and the RCA2600 for an ILS - it was a pleasure to use....partial panel? I don't see no partial panel .

If a solid state device fails, it goes blank or X's out so you know it's not reliable. Mechanical gyros can die slowly and, unless your scan is really good you may not recognize quickly enough that it's providing errant information. As I've stated before, I'm done buying mechanical gyros!

[rbridges]

1 hour ago, FlyDave said:

 

If a solid state device fails, it goes blank or X's out so you know it's not reliable. Mechanical gyros can die slowly and, unless your scan is really good you may not recognize quickly enough that it's providing errant information. As I've stated before, I'm done buying mechanical gyros!

good point.  I didn't realize it was such a gradual fail until mine failed during a VFR flight.  Since it was bright, it took me a while to notice the low vacuum light.

[Bennett]

Mid Continent manufactures their LifeSaver backup electrical AI with built in battery. I had one installed a couple of years ago, and it is perfect as a backup instrument. You can order it with an inclinometer for the ball.

[Jerry 5TJ]

Just say No to mechanical spinning gyros. 

 

[MooneyBob]

I will go most probably with Sandia SAI 340  

 

 

[PMcClure]

On November 24, 2015 1:50:39 PM, ChrisH said:

If you go solid state, why not go all the way with http://www.aircraftspruce.com/catalog/inpages/sai340-11-12817.php.

If for nothing else, the backup battery.

Why does this instrument have vacuum fittings on the back?

And how do these new solid state AI's work with analog A/P like the KFC 150 or 225. I guess there would be no flight director?

[Marauder]

On November 24, 2015 1:50:39 PM, ChrisH said: If you go solid state, why not go all the way with http://www.aircraftspruce.com/catalog/inpages/sai340-11-12817.php.

If for nothing else, the backup battery.

Why does this instrument have vacuum fittings on the back?

And how do these new solid state AI's work with analog A/P like the KFC 150 or 225. I guess there would be no flight director?

If they are like the Aspen, the digital signal generated by the AHRAs is translated into analog through a separate box. In the case of the Aspen, it is an EA100.

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[Bennett]

On November 24, 2015 1:50:39 PM, ChrisH said: If you go solid state, why not go all the way with http://www.aircraftspruce.com/catalog/inpages/sai340-11-12817.php. If for nothing else, the backup battery.

Why does this instrument have vacuum fittings on the back? And how do these new solid state AI's work with analog A/P like the KFC 150 or 225. I guess there would be no flight director?If they are like the Aspen, the digital signal generated by the AHRAs is translated into analog through a separate box. In the case of the Aspen, it is an EA100.

Sent from my iPad using Tapatalk

Reply from Bennett:

The fittings on the back are for the Pitot Static system. When I was at the Palm Springs show I asked about autopilot interfaces. I was told that there were none. As I understand it, the unit can be primary only as an AI.

[Marauder]

On November 24, 2015 1:50:39 PM, ChrisH said: If you go solid state, why not go all the way with http://www.aircraftspruce.com/catalog/inpages/sai340-11-12817.php. If for nothing else, the backup battery.

Why does this instrument have vacuum fittings on the back? And how do these new solid state AI's work with analog A/P like the KFC 150 or 225. I guess there would be no flight director?

If they are like the Aspen, the digital signal generated by the AHRAs is translated into analog through a separate box. In the case of the Aspen, it is an EA100.Sent from my iPad using Tapatalk

The fittings on the back are for the Pitot Static system. When I was at the Palm Springs show I asked about autopilot interfaces. I was told that there were none. As I understand it, the unit can be primary only as an AI.

For most non King rate based autopilots they use an ACU to do the A/D conversion.

[Ned Gravel]

How do you demonstrate a Rate 1 turn without a turn coordinator?  Am I missing something?

[cnoe]

How do you demonstrate a Rate 1 turn without a turn coordinator?  Am I missing something?

In a piston single it's as simple as 15% of airspeed (kts TAS) = bank angle. Easy peasy.

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[LANCECASPER]

4 minutes ago, Ned Gravel said:

How do you demonstrate a Rate 1 turn without a turn coordinator?  Am I missing something?

Standard rate is 20 degrees. Just do the turn a little past the 15 degree markings on the AI.

[cnoe]

Standard rate bank angle depends on airspeed. The best reference on the subject I've ever seen is http://www.luizmonteiro.com/Article_Bank_Angle_for_Std_Rate_05.aspx

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[bradp]

Nice to see the Sandia unit TSO'd.  If they had gotten the altimeter function TSOd as well and, being a solid state instrument, leveraged that altimeter as an encoding unit they would have hit a grand slam.  Still pretty cool.  

[Ned Gravel]

OK.  Got it.  15 degrees for 100 knots (115 mph), 20 degrees for 130 knots (150 mph), 25 degrees for 170 knots (196 mph).  All in TAS, of course so I would have to do that calc first.  Just being safe (because the errors are from 0 to 3 degrees from 100 to 170 knots), in a pinch, I can stick to 20 degrees throughout the envelope.

[Marauder]

How do you demonstrate a Rate 1 turn without a turn coordinator?  Am I missing something?

In a piston single it's as simple as 15% of airspeed (kts TAS) = bank angle. Easy peasy.

Sent from my iPad using Tapatalk

OK.  Got it.  15 degrees for 100 knots (115 mph), 20 degrees for 130 knots (150 mph), 25 degrees for 170 knots (196 mph).  All in TAS, of course so I would have to do that calc first.  Just being safe (because the errors are from 0 to 3 degrees from 100 to 170 knots), in a pinch, I can stick to 20 degrees throughout the envelope.

Or you could be lazy and match the turn rate to the standard rate indicator on the Aspen display.

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[cnoe]

2 hours ago, Marauder said:

 

Or you could be lazy and match the turn rate to the standard rate indicator on the Aspen display.

 

Isn't that what the A/P is for? After all, that yoke thingie makes my hands cold in the wintertime.