AHRS & Aerobatics

cptndavis

New Member
Does anyone know if the new AHRS gyros are ok to use in aerobatic airplanes??
I assume since there are no moving parts to an AHRS unit, there is nothing to break or topple as with a conventional gyro. Does anyone have any experience installing or using a system with digital gyros, like the G1000 or Aspen PFD, in an aircraft that is also used for aerobatics??
 
I've also been wondering this. I've asked several CFIs here at UND if you can lose AHRS data in an unusual attitude, and they don't know. I know that if you've lost AHRS data in the G1000 you have to be in straight-and-level unaccelerated flight to have the best chance of an AHRS reset, but beyond that I have no knowledge of the limitations of the AHRS in the G1000. I have even less knowledge of the AHRS system in the Entegra, but I don't even think it's possible to do an airborne reset of it's AHRS.
 
Yes, I am not too sure about the Integra unit either. I was told by the folks at Aspen for their new PFD 1000 unit that under unusual attitudes if the AHRS loses orientation than you just do a in flight reset when you are straight & level. But I'm not sure they tested this out and I'm not sure if they documented whether constant unusual attitudes/aerobatics will eventually throw the system out of whack.
 
I know that if you've lost AHRS data in the G1000 you have to be in straight-and-level unaccelerated flight to have the best chance of an AHRS reset, but beyond that I have no knowledge of the limitations of the AHRS in the G1000. I have even less knowledge of the AHRS system in the Entegra, but I don't even think it's possible to do an airborne reset of it's AHRS.
The G1000 can do an airborne reset up to 20 degrees of bank. Attitude information also comes from the GMU (Magnetometer). It not only senses magnetic heading, but also orientation in relation to the earths magnetic field. Try it if you get a chance, its pretty cool.
 
I remember doing power on stalls and slow flight and the GMU was "throwing up" as a Garmin engineer put it. It would flash on and off then just quit only to come back on after 5 minutes.
 
Yeah, you might make it freak out temporarily, but the important thing is that there will be no long-term damage done (unlike mechanical gyros). Also, as others pointed out, the G1000 does a fine job of an airborne re-align.
 
Actually, none other than Bill Kershner labeled the whole thing about modern mechanical gyros not lasting an OWT. He ran Aerobatic 152s with gyros and had no difference in failure rate verses his non-aerobatic airplanes. We'll see how long my AI goes- it's got over 900 hours on it so far.
 
Actually, none other than Bill Kershner labeled the whole thing about modern mechanical gyros not lasting an OWT. He ran Aerobatic 152s with gyros and had no difference in failure rate verses his non-aerobatic airplanes. We'll see how long my AI goes- it's got over 900 hours on it so far.
Well, that's interesting! How modern are the modern mechanical gyros he talks about?
 
I've also been wondering this. I've asked several CFIs here at UND if you can lose AHRS data in an unusual attitude, and they don't know. I know that if you've lost AHRS data in the G1000 you have to be in straight-and-level unaccelerated flight to have the best chance of an AHRS reset, but beyond that I have no knowledge of the limitations of the AHRS in the G1000. I have even less knowledge of the AHRS system in the Entegra, but I don't even think it's possible to do an airborne reset of it's AHRS.


It depends on how old the G1000 is. Older versions (pre - 2007 models) pull attitude information off of an actual AI behing the PFD. newer ones, have a digital one. But with all of them you can reset he AHRS inflight, just keep the wings level and cycle the avionics or cycle the AHRS c/b.

From my experience G1000 usually does good with unuasual attitudes, but I have had to reconfigure a few after they spun the plane. Not that hard to do if you know a guy that is a trained G1000 tech. I don't think I have had to replace any Parts in a G1000 because of playing around yet......
 
It depends on how old the G1000 is. Older versions (pre - 2007 models) pull attitude information off of an actual AI behing the PFD. newer ones, have a digital one. But with all of them you can reset he AHRS inflight, just keep the wings level and cycle the avionics or cycle the AHRS c/b.

From my experience G1000 usually does good with unuasual attitudes, but I have had to reconfigure a few after they spun the plane. Not that hard to do if you know a guy that is a trained G1000 tech. I don't think I have had to replace any Parts in a G1000 because of playing around yet......

Incorrect.... There is a turn coordinator located behind the PFD on the KAP-140 autopilot models to provide for roll steering. There is no attitude indicator located behind the panel. The AHRS provides attitude information in all models.
 
You are correct, unless it's within 20 seconds the Entegra system will not reset. The G1000 obviously but with the new Cirrus Perspective it will be interesting to see if you can even shake both of the AHRS. Gotta wonder. I know that a company called Dynon.

Here is one website I found.
http://www.avionix.com/store/dynon.html

and here is Dynons actual home page.
http://www.dynonavionics.com/

Hope it helps.

I also found out later that it is mainly for homebuild and light sport aircraft! sorry. I know there are some out there. I used to fly into CGI and Cape Avionics alot and they were putting a glass panel into a extra 300? not totally sure. But I know that they are out there.
 
From my experience G1000 usually does good with unuasual attitudes, but I have had to reconfigure a few after they spun the plane. Not that hard to do if you know a guy that is a trained G1000 tech. I don't think I have had to replace any Parts in a G1000 because of playing around yet......[/quote]


What does reconfiguration of the unit entail?? Will an inflight restart suffice??
 
What does reconfiguration of the unit entail?? Will an inflight restart suffice??

An inflight restart is different from a Reconfigure. if you can get the problem to go away after you restart the system then that is all you need. you really Don't even need to mention it to your mechanic. Well, that is unless it happens more than once.

But if it does not go away by cycling the system then MX has to reconfigure the system. A Reconfigure is done on the ground thru the maintenance pages. There is two way this can be done, 1, using data that is stored on the GIA to "refresh" the settings for the failed part. The other is a Target load. The target load is a little more in depth, but 98% of the time, nothing more than putting files on an SD card and re-installing them on the GIAs.
 
I remember seeing Greg Poe's Edge 540 having a Chelton EFIS display, but this was at least two summers ago. Not sure if there was any problems with it though.

Here is the specs:

AHRS (Attitude/Heading Reference System)

  • Inertial AHRS with three solid-state angular sensors, three solid-state accelerometers and three magnetometers
  • Non-tumbling, non-precessing
    Size: 4.66"w x 4.863"h x 5.909"d
    Weight: 4.6 lbs.
    Electrical: 9 to 30 VCD, 0.14 amps max @ 28 VCD
    Operating temperature: -40 to 70 degrees C
    Storage temperature: -55 to +85 degrees C (non-condensing)
    Mounting: Remote
 
Thanks for all the info. I am thinking about the Aspen PFD 1000 unit for my airplane. I'm not sure if this unit has been installed in any acro aircraft yet, but I'll just hope for the best.
 
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