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rjtjrt
08-12-2007, 08:13 PM
In certified aircraft autopilots are not renown for reliability.
Any reports of reliability on the various autopilots builders put into their homebuilts? And how much use of said aotopilot?
John

kevinh
08-12-2007, 08:59 PM
My TruTrack Pictorial Pilot has never had a problem - 190ish hours. About half of those hours are XC and I used it at least once per XC flight.

My Altrack control unit died a few months ago (2 yrs of flying, and 4 years since I purchased). TruTrack repaired it and FedExed it back - no charge! As opposed to many certified APs the control unit is entirely solid state, so I suspect a failure is unlikely...

Ironflight
08-12-2007, 09:29 PM
550+ hours with the Pictorial Pilot and Altrak - no problems yet.

I remember growing up with simple autopilots in rental Cessnas and Pipers....if they ever worked at all, they tried to aileron roll you as soon as they were engaged! Technology has come a LONG way....:)

Sam Buchanan
08-12-2007, 09:50 PM
In certified aircraft autopilots are not renown for reliability.
Any reports of reliability on the various autopilots builders put into their homebuilts? And how much use of said aotopilot?

The following units have flown in my RV-6:

1) Navaid, ~400 hrs. Control head was returned to factory once for defective turn coordinator display. Operationally, the device was about as good as can be expected from an analog system using low-cost components. The newer digital systems offer far more features and reliability. The servo (~800 total hours) has been trouble free and is still used with my Trio Avionics EZ-Pilot.

2) TruTrak AlTrak, ~300 hrs. A very simple system that operated as designed with no problems. Was replaced with Trio EZ-Hold because I wanted climb/descent/target altitude features.

3) Trio Avionics EZ-Pilot, ~400 hrs. Because I have flown this system since its earliest days, I worked through some minor issues with very early software. The software released in the past couple of years has been flawless and there have been no operational issues. I have flown three versions of this device, all with different displays.

4) Trio Avionics EZ-Hold, ~250 hrs. Software and hardware has been flawless and I have flown EZ-1, EZ-2, and EZ-3 versions of this device along with several different generations of software.

All in all, these systems have been rock solid. The current generation of digital autopilots are amazing devices especially considering their features and prices.

MarkC
08-13-2007, 02:16 AM
230+ hours and a Trutrak Digiflight IIVS with no problems. It flies the plane much more than I do :-)

Mark - N234C
RV-7 - 230hrs+

w1curtis
08-13-2007, 05:23 AM
In certified aircraft autopilots are not renown for reliability.
Any reports of reliability on the various autopilots builders put into their homebuilts? And how much use of said aotopilot?
JohnYou must be basing this on the old Cessna/ARC autopilots. Not that I'd put one in my RV-10 because there are better products (Trutrak) out there for the experimental market but S-Tec owns the certified and certified retrofit market and they are VERY reliable. I've had the S-Tec 30 in my 177RG since install in 2003 and it has been 100% reliable. The TruTrak that I've selected for my RV-10 also has a proven track record for the experimental market.

kentb
08-13-2007, 12:09 PM
I remember growing up with simple autopilots in rental Cessnas and Pipers....if they ever worked at all, they tried to aileron roll you as soon as they were engaged! ....:)
I was wondering where you learned to do acro. ;)

Kent

rv9av8tr
08-13-2007, 01:53 PM
I had a Navaid Devices wing lever unit in my LEZ for 22 hrs (1200 hrs) and never had any troubles with it. I'm going with the same unit in my new -9A.

SteinAir
08-15-2007, 09:30 PM
I had a Navaid Devices wing lever unit in my LEZ for 22 hrs (1200 hrs) and never had any troubles with it. I'm going with the same unit in my new -9A.

Let me preface this by saying it's a little tongue in cheek...but food for thought none the less.

My 1946 Aeronca Chief (used to have) had a nice cork with a piece of wire on it and a little dab of red paint for the fuel guage. Worked well for decades - but - on my RV6 did I want to use the same thing?! Sure it'd work, but..... ;)

Just my 2 cents as usual!

Cheers,
Stein.

Wayne
08-16-2007, 07:04 AM
I have the pictorial pilot and altrack alt hold. Everything worked great for the 1st 90 hours then the altrack would not hold the altitude anymore and would hunt for it. I called TruTrak and they said never heard of that problem and never have any problems with the Altrak - send it back and we will repair.
At Oshkosh this year I made a comment to the RV4 pilot next to me about the Altrak and he said that he removed his because it would not hold and the factory could not fix and the RV6 pilot next to him also was having problems with the Altrak. Maybe the Altrak is having more problems than the factory want to admit however they are very customer service orientated which helps.
I haven?t taken the time to pull the Altrak unit and send back so I have no conclusion to this story.

BTW-my pictorial display will occaisionaly not dispaly level (but is flying level) Kind of disconcerting and doesn?t help the confidence factor when flying on instruments. The factory had no comment on this sporadic problem

Sam Buchanan
08-16-2007, 07:05 AM
In response to this:

I had a Navaid Devices wing lever unit in my LEZ for 22 hrs (1200 hrs) and never had any troubles with it. I'm going with the same unit in my new -9A.


Stein replied:

Let me preface this by saying it's a little tongue in cheek...but food for thought none the less.

My 1946 Aeronca Chief (used to have) had a nice cork with a piece of wire on it and a little dab of red paint for the fuel guage. Worked well for decades - but - on my RV6 did I want to use the same thing?! Sure it'd work, but.....


Good reply, Stein.

I wanted to reply to that post but couldn't figure out a diplomatic way to do it. :)

RVadmirer
10-12-2007, 10:09 PM
...but with less pleasant prior experience. My Navaid has always taken several attempt to lock on to a track and do it's job. The first couple do that Cessna trick previously mentioned. On a recent flight home to Cal from TN it quit doing anything useful. Nothing but trimming constantly kept it headed in the right direction. Would run me off on weird tracks, made reversing 90 degree turns and made a full circle once. I'll send it in for service but am ready to move up to better gear despite the cost. :o

Bob Axsom
10-13-2007, 02:35 AM
Pictorial Pilot and Altrak in our RV-6A for the past ~270 hours. Perfect performance. As with any physical system if the external forces exceed the force of the system it will yield to the external force (pilot inputs, strong vertical air currents, gross CG offsets from datum). I am not aware of any MTBF, failure modes & mitigation analysis but in the everyday world of IFR flying I manage my fuel distribution (4 tanks) and trim for level flight activate the pictorial pilot and altrak and it stays on course and altitude - all the time. When I pass over a VOR, I just dial in the new angle in the pictorial pilot and the plane tracks the desired course. When an altitude change is required I hit the ALT button to disengage Altrak fly to the new altitude hit the ALT button again to engage Altrak and it hold the altitude well within one division on the altimeter (less than 20 ft). When I hand flew for the first year before installing the autopilot ATC would ocassionally verbally jab me for heading or altitude but now I only hear from them when there is a frequency change or an amendment to my clearance. In such a maneuverable and fast airplane this is a good thing in the IFR system and when I want to enjoy the freedom of VFR flight I just have them setting on and ready for engagement when I want to change charts or study something.

I had an Archer II for 22 years with a Century single axis autopilot and I never used it for well over 4,000 hours of IFR and VFR flying except to ocassionally verify that it still worked. It would snake through its little bug capture routine and hold a heading if the fuel imbalance did not get too great for it. The RV is a whole different flying experience and you do not have much time to make a correction before a noticable deviation occurs. The rock solid track and altitude provided by the autopilot has been very reliable.

Bob Axsom

Skytrash
10-13-2007, 04:43 PM
I have a Trutrak Digiflight 2 VSGV and use it everyday for nearly all of the hour and a half flying time to and from work. I have over 850 hours on the airplane and I would guess over 500 of them using the autopilot with no problems.

Just another data point for you.

n5lp
10-13-2007, 05:31 PM
My airplane was built with a Navaid Devices autopilot. That is an amazing device for the time but the time is in the past.

The Navaid is a VERY analog device. It gets rate of turn by balancing the turning force on the gyro against springs. I got pretty familiar with mine over the years because I had to take it apart and adjust gyro balance so many times, because it would show a turn in straight flight. Even when brand new the rate of turn indication was vastly different, and wrong, for left and right, caused simply by different spring tensions.

During all this it would work fine for the basic task of tracking the GPS course.

I swapped out for the Trio EZ Pilot a while back and it is a different world. Many more functions, like holding a random ground track not entered as a course on the GPS or changing a desired track a certain number of degrees (ATC instruction to turn 15 degrees left). Most appreciated is the lack of a need to tinker with it all the time.

I'm still using the Navaid Devices servo and it is working fine. The head is now displayed on my shelf that holds obsolete devices, alongside my WWII era DG and my vacuum pump.

RVadmirer
10-13-2007, 10:23 PM
Larry, am deciding to move up to the Trio now and quit hassling with the Navaid. If the servo does OK, I guess I'll keep it for now to keep the upgrade costs down. Look forward to real world Autopilot rather than the constant tinkering to keep it going the right way!

Jim, did you folks move and is Vickie commuting with you every day? What happens when the fog comes in? I'm thinking of doing the same but am not instrument rated. Pine Mt. and Columbia look better and better all the time..:rolleyes:

Thanks again for the input,
Dave