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Brantel
05-15-2010, 07:05 PM
Initially my panel was designed around using Dynon's AP. The first half of my Phase I testing has been sans AP because I did not purchase the servos and install them until this week. Originally the panel and the plane were built with the brackets installed, holes drilled and wires ran to make it easier to add the servos later. My cash flow prevented the purchase of the servos earlier this year so they had to wait.

I have a D100, D120, HS34, AP74 and a SV32 in the wing for roll and a SV42 in the back for pitch. I used the Dynon install kits and used the Stein bundle for the servo wiring.

I am starting with firmware version 5.3 so all of my experiences with the Dynon AP will be from that point forward. Major enhancements have been made to the AP firmware since the intial release!

I chose to go ahead and use the SV42 instead of the recommended SV32 for pitch due to the fact that several post here state that the SV32 indicates too much slipage even at 100% torque in the RV7. I would rather have too much torque available and limit the torque % rather than not have enough. For roll, the SV32 seems to be more than enough and I even have the torque % on that backed off a bit.

The install went flawless and Dynon has done a great job with the documentation. The expoded views and the 3D models really make this a no brainer. I did however use an additional washer under the bearing that attaches to the elevator bellcrank to provide additional clearance of the pushrod jam nut to the bellcrank. The hardest part was safety wiring the three servo mount screws while "in the position" of laying thru the seat back bulkhead between the side of the fuse and the flap motor box and into the baggage compartment. This is no small task for a fat man!!!!

The setup and configuration/testing of the AP system went flawlessly and just as explained in the manuals. Very well done by Dynon. It almost idiot proofs the initial setup of the system.

Once configured, the AP is ready to use and since I have the AP74, the operator interface of the AP is second to none. Really easy to operate and the features of the AP/AP74 combo are really amazing for the price. To get comparable features that Dynon includes by default would push you into much more expensive units with the competition. If they ever enable vertical guided modes (AP76 or other), this thing will be for the most part as complete as anyone could ever desire. Even GPSS is supported out of the box with the HS34. VOR/LOC modes are free as well which is something that only the high end TT's support natively.

My in flight testing has been limited at this point so I will make regular updates to this thread as I continue to use the AP.

The initial testing I have done must really be an improvement over past firmware releases in the roll axis. I have started with the new control method that Dynon gives you the option to select and I can tell you that the AP will nail HDG mode rock solid, GPS Trak mode is also rock solid, turns to a new HDG or GPS Trak are smooth and accurate. Have not done any extensive GPS Nav modes yet so I have not intercepted a course at different angles or overflew a waypoint yet. All I have driving at this point is a X96 GPS so I cannot report on GPSS mode.

The pitch axis seems to also work very well. I was not expecting it to work as well as it does based on some of the reports. Altitude changes worked very well. Little to no overshoot at the target. The unit has shown me that it can hold alt to +-10ft in some light chop.

All of these comments may change when I get more time on the unit in different turbulence conditions. Time will tell. Right now I am happy as a clam that it works as well as it does with little to no tuning required on my end. You can't beat the price point to enter into an advanced feature set dual axis AP....

Please do not use these post as a sole method for chosing an AP. One man's opinion is not enough info to make a choice.....when it comes to these things, results sometimes vary and vary greatly...

More to come later!

hydroguy2
05-15-2010, 07:57 PM
nice report Brian

happy as a clam is always good

rvmills
05-16-2010, 12:10 AM
Brian,

As Brian II said, nice report. Glad it went together so well and is performing so well. Big head nod here when you described the pitch servo bracket triple-bolt-safety-wire-fun. I don't have a flap motor tower, so I could twist and roll a little more, and it still was a bear. Got a few nice bruises...mostly because it took me several tries to get it right...rookie (me :p evidence was the pile of twisted wire I drug out with me when I was done!!)

Interested in what Sensitivity and Tq setting you're using, and will look forward to your updates. One phrase caught my eye: "I have started with the new control method that Dynon gives you the option to select". Maybe I'll do a V8 salute when you tell me, but what does that mean? Mostly good roll performance on mine, but if there is a new setting I missed reading about in 5.3, I'm very interested.

Thanks again for the report!

Cheers,
Bob

RV10inOz
05-16-2010, 02:58 AM
There is a choice between roll ate turns or angle of bank turns. The AOB turns seem to be a little nicer in feel, or so it seems!

Good work Brian!

DB

WenEng
05-16-2010, 04:23 AM
I am so on the fence whether to go TT or Dynon. I still am unsettled, but this helps me. Now, if only Dynon can work on the AP76. There is something to be said for having a separate system, just in case....... Like I said, I am working through that decision making process now.

Brantel
05-16-2010, 07:56 AM
Bob,

Its in the roll axis....Every report that I have read of people that switched from the original method to this method that was made available with 5.3 was very positive so I just decided to start with this setting....

Here is a short blurb from Dynon on the new control method option:

"Autopilot Details: Dynon continues to enhance the autopilot functionality. Release 5.3 adds a new roll mode that improves the performance for aircraft that have experienced issues. To try this mode simply set TRN RT LMT to 0. The autopilot will more directly control bank angle instead of targeting a specific turn rate. The maximum bank angle that the autopilot allows is still limited by the BANK LIMIT parameter. In this mode, set the BANK ANGLE LIMIT to the maximum value you want the autopilot to use in a turn. There are no pitch changes in Version 5.3; additional autopilot enhancements will come in a future release."

"I have started with the new control method that Dynon gives you the option to select". Maybe I'll do a V8 salute when you tell me, but what does that mean? Mostly good roll performance on mine, but if there is a new setting I missed reading about in 5.3, I'm very interested.

Thanks again for the report!

Cheers,
Bob

Brantel
05-16-2010, 08:30 AM
One thing about the servos:

I have read many reports that the servo's could have too much play between the output arm and the shaft. This can be caused by slop between the arm and the shear screw. Dynon even put out a SB on the issue that states that there should be no play whatsoever between these two parts.

Well my brand new servo's have some play but I decided that what little play there is should not be an issue and so far that has been correct. From looking at the design, it is almost always going to have a little play. Another place that I see that slop is getting introduced is the fact that Dynon uses a nylon washer under the nut that holds the arm on. That washer gets compressed due to the off axis loads being applied to the arm. This allows for some slop as well. There is also some built in gear lash inside the gearing section of the servo. All three of these added up allows for some slop in the overall setup.

Interestingly though, I have not found this to be an issue with the performance so far. Although my testing has been limited and my opinion here may change.

I have seen other brand servos and all of them have some play between the motor and the arm.

RV7ator
05-16-2010, 08:48 AM
Hi, Brian,

I'd like for you to expand on your meaning of "rock solid" for heading and GPS track mode.

I had a -7 (sold) with v5.1, and based on its performance the current project will get a Tru-Trak (I have several favorable experiences with TT). Dynon dynamic performance on intercepts and limiting variations from target went well when directing the aircraft, but where it failed was in doing...nothing. Pitch and roll would occasionally giggle and wiggle in smooth air, light disturbances making it even more prone to oscillations. There was no combination of torques, sensitivities, linkages, blessings or curses from me or Dynon that would totally damp unwanted activity. I also discovered that the unit was really, really sensitive to yaw trim. The slightest displacement of the ball from exact center of the cage exacerbated roll problems. 5.3's new mode may obviated this issue, but what about pitch?

So I'm real interested in what you discover in droning, straight-line flight. I'd prefer Dynon over TT for $ and features in the current project, but... see the above.

John Siebold

Brantel
05-16-2010, 09:13 AM
John,

I will report my findings more as I test...I am a tell it like it is kind of guy even if I have to talk bad about my choices in gear....I will also give praise when praise is due.

As far as stability in smooth straight and level flight, what time I have in this mode was very good. I have not experienced any twitchyness like you describe.

5.3 has a new method for controlling roll and that may have eliminated the issues you had as I have no reason to try the original mode since the new mode seems to work so well.

5.3 does not have any pitch enhancements per Dynon but maybe 5.2 did?? not sure. The beta testers that I talk too state that there were many changes to the AP firmware between original release and 5.3 and they all say that Dynon is working hard on more to come.

Will report as I have more info.

Hi, Brian,

I'd like for you to expand on your meaning of "rock solid" for heading and GPS track mode.

I had a -7 (sold) with v5.1, and based on its performance the current project will get a Tru-Trak (I have several favorable experiences with TT). Dynon dynamic performance on intercepts and limiting variations from target went well when directing the aircraft, but where it failed was in doing...nothing. Pitch and roll would occasionally giggle and wiggle in smooth air, light disturbances making it even more prone to oscillations. There was no combination of torques, sensitivities, linkages, blessings or curses from me or Dynon that would totally damp unwanted activity. I also discovered that the unit was really, really sensitive to yaw trim. The slightest displacement of the ball from exact center of the cage exacerbated roll problems. 5.3's new mode may obviated this issue, but what about pitch?

So I'm real interested in what you discover in droning, straight-line flight. I'd prefer Dynon over TT for $ and features in the current project, but... see the above.

John Siebold

rvmills
05-16-2010, 10:34 AM
Thanks Brian. I have seen discussions about setting turn rate to zero, but had not seen the blurb you just posted. Couldn't figure out why one would set it to zero from my reading various posts on the Dynon forum, but eliminating turn rate as a control parameter and using only the max AOB as the setting makes perfect sense. It eliminates the need for the AP from trying to adjust AOB to match an average turn rate.

There's my V8 salute! ;)

Guess what I'll be testing out next week (when I get back from this trip).

Thanks much, and happy flying in Phase I and beyond!

Cheers,
Bob

Brantel
05-16-2010, 10:48 AM
Thanks Bob,

There is also a little more info in the latest install manual...



Thanks Brian. I have seen discussions about setting turn rate to zero, but had not seen the blurb you just posted. Couldn't figure out why one would set it to zero from my reading various posts on the Dynon forum, but eliminating turn rate as a control parameter and using only the max AOB as the setting makes perfect sense. It eliminates the need for the AP from trying to adjust AOB to match an average turn rate.

There's my V8 salute! ;)

Guess what I'll be testing out next week (when I get back from this trip).

Thanks much, and happy flying in Phase I and beyond!

Cheers,
Bob

rvmills
05-16-2010, 01:30 PM
Thanks Bob,

There is also a little more info in the latest install manual...

Good call...thanks! If my count is correct, that's two install manual updates you've keyed me into.

So I'm owin' two cases or bottles so far! You gonna be at OSH this year to collect? :)

I'll be in Sleepy Hollow in a rented trailer, and if all goes well, I'll be parked with the Airventure Cup planes. Let me know the brand!! :D

Cheers,
Bob

prporter
05-16-2010, 08:11 PM
What you might want to do is check with one of the companies that build panels, and one that works with several different manufacturers. I had my mind set on brand "x', but after some discussion with a couple of the builders, have decided to go with "y". They are the ones who get many of the calls when it doesn't function properly and can give a fairly unbiased opinion.

Brantel
05-16-2010, 09:34 PM
Which Autopilot? Which one meets your mission for a price you can afford? All of the remaining players in this experimental AP market are well proven customer service oriented companies that are more than likely not going anywhere in the near future.

Panel shops unbiased? Hmmmmm :confused:

Scott Hersha
05-17-2010, 09:03 PM
Brian,
I agree. You can get a better autopilot, but you'll pay a lot more. The new 5.3 improved roll to the point that I would use it IFR if so inclined (I'm not equiped). They tell me that the next software upgrade will do the same for pitch. My pitch axis stability is not that bad for VFR, unacceptable for IFR right now. It varies +- 50' in smooth air. In turbulence, it gets uncomfortable and I turn it off. Heading is also unusable because the heading indicator varies back and forth constantly. 3 other RV's that I know of in Cincinnati with the same setup do the same thing. NAV and TRK work quite well though, go figure. Great VFR autopilot for the money though and it will probably get better in pitch with the next upgrade. If I decide to reconfigure to an IFR setup (probably won't), I will include replacing the autopilot with a TruTrak. I had one in my RV-6 and it was flawless - but more expensive.

Brantel
05-18-2010, 05:09 AM
I suspect the HGD issues are not related to the AP but related to why is the HDG indicator swinging around...After all the AP is trying to follow the HDG indicator.

I have not noticed my HDG indicator moving around much unless the tail does the RV wiggle. I took great pains in mounting and calibrating my remote compass so that might have helped but I am sure you guys did as well.

Is Dynon not the only one (experimental AP's) that actually does Magnetic HDG hold mode?

Time will tell how much better Dynon can make the AP. I suspect we will see some good progress soon.

The only thing I don't understand is why similar model planes have such different results with the AP....

Brian,
I agree. You can get a better autopilot, but you'll pay a lot more. The new 5.3 improved roll to the point that I would use it IFR if so inclined (I'm not equiped). They tell me that the next software upgrade will do the same for pitch. My pitch axis stability is not that bad for VFR, unacceptable for IFR right now. It varies +- 50' in smooth air. In turbulence, it gets uncomfortable and I turn it off. Heading is also unusable because the heading indicator varies back and forth constantly. 3 other RV's that I know of in Cincinnati with the same setup do the same thing. NAV and TRK work quite well though, go figure. Great VFR autopilot for the money though and it will probably get better in pitch with the next upgrade. If I decide to reconfigure to an IFR setup (probably won't), I will include replacing the autopilot with a TruTrak. I had one in my RV-6 and it was flawless - but more expensive.

Scott Hersha
05-18-2010, 08:52 AM
I don't get it either. Jon Thocker and I have two airplanes that are as close as you can get and to get the same pitch performance, he has his set at 6 and I have mine set at 25 (max). If I had mine set at 6, I'd get airsick trying to hold altitude in smooth air....

dedgemon
05-18-2010, 08:57 AM
I suspect the HGD issues are not related to the AP but related to why is the HDG indicator swinging around...After all the AP is trying to follow the HDG indicator.
[\QUOTE]

Yep, its just trying to follow a poor (or no) calibration on the mag. I saw the same thing and a "careful" calibration made a HUGE difference.



[QUOTE=Brantel;433683]
The only thing I don't understand is why similar model planes have such different results with the AP....

I think the key is similar, not same. Some of the early issues were clearly with builders that had more that normal slop or deadband in the controls. Causes a limit cycle that can be really tough to compensate in the autopilot.

My performance with 5.3 is really very solid. Even pitch seems to be very good.

rv7boy
05-18-2010, 09:02 AM
...Jon Thocker and I have two airplanes that are as close as you can get and to get the same pitch performance, he has his set at 6 and I have mine set at 25 (max)...

Maybe his AP performs differently because he's flying with his canopy open! :rolleyes: (See today's VAF news link (http://vimeo.com/11809242) 5/18/10)

P.S. don't take me seriously...just joking!

rvmills
05-18-2010, 11:44 AM
There are times when I see some heading oscillations as well. Kinda drives me batty, as I can't figure out why they appear. Not radical, just a few degrees backand forth, so it may be just a little aircraft movement in flight is causing the heading to move a little.

Another factor may be the strength of the MAG CAL. I've done a number of MAG CAL routines as I've done testing and firmware upgrades over the past year and a half. Last week my compass seemed a bit off on runway heading, and my G396 wind readout seemed far-fetched, so I checked things out on the compass rose at home plate. N/S were dead on, and E/W were off 10 degrees. Not sure when that happened, but I had done the 5.3 upgrade since the last cal.

Any idea if drift such as that can be introduced by a FW upgrade? Any other thoughts on why it might happen? (I've done no other new equipment installations since the last cal, magnatometer is in the mid-aft fuselage on the bottom skin).

So last week after seeing the discrepancey, I did a new MAG CAL on our compass rose...engine running and all avionics on. Went out and did some speed test runs, but no AP work. Planning on setting that turn rate to zero, rechecking the compass on the rose, then heading out for some AP testing, to see if heading is even more solid. My last use of the AP (on a X-C to a formation clinic) was after installing 5.3 but before this most recent MAG CAL, and showed the typically good NAV and TRK hold, and improved HDG hold, though still a bit drifty at times. Hopefully this fresh MAG CAL and setting the turn rate to zero will dial it in the rest of the way.

FWIW, I've been running at 8 roll and 16 pitch, and I drop it down 1-2 in each axis in light chop. If the next FW update improves pitch as mentioned above, that will make this AP really, really nice, as its working pretty darn well now.

Thanks for the continuing discussion!

Cheers,
Bob

rvmills
05-20-2010, 01:10 AM
Brian and the gang:

I did a test flight today after setting the turn rate setting to zero, and swinging throught the compass rose just to be sure the last cal had held (it had).

Conditions weren't ideal for an AP test hop, but actually yielded a bit of a good, challenging test...which the AP did pretty well on. Some smooth air, but a fair share of light chop, and even a near-moderate bump from time to time. Overall, I was impressed with the performance today. Thought I'd post a few notes and see if it matches your results Brian (and others). Just a few more data points for the team. I used settings: 15 pitch, 500 FPM vertical speed, 8 roll, 25 deg AOB max, and 100% Tq (SV-32s).

The roll mode did seem more solid with the new setting. HDG held +/- 1-2 deg in smooth air, and 2-3 deg in light chop. I saw a couple 10 deg excursions in moderate bumps, but that seemed more a wing waggle and tail wiggle (as you described it Brian). Turns to headings showed a smooth roll-in to 25 deg, and no waggle in the turn. I did note that the roll-outs were consistently started about 20-30 degrees prior to the selected heading, and the last part of the turn was pretty slow...like it was "sneaking up" on the selected HDG. Not bad or uncomfortable, just took a bit longer to get on the selected HDG, FWIW. Anyone else see that behavior?

NAV was very solid, perhaps even better than before the change. TRK was solid too, and I played with changing the track with the "TRK bug" (and Barry, yes, the yellow HDG bug turns magenta when you engage TRK on the AP, and it functions just as you described). Something I had not played with before.

Descending turns worked quite well too, and pitch was pretty solid in the descent and when level, given the conditions. I was maneuvering for most of the test hop, so it will be interesting to see how it flies on my next X-C.

Sure seems like Dynon is working through the little bugs, and this is turning out to be a pretty nice AP for X-C/VFR (that's as far as I can test with my equipment). Would love to test the NAV capability with an IFR GPS or an SL-30, and see how localizer tracking and the VSI setting would work during an approach. (Hey, Greg A, can you come out and play?) :D

Please keep the reports coming Brian (and others)!

Cheers,
Bob

Brantel
05-20-2010, 08:33 PM
Today I spent 2.5 hrs behind the Dynon AP...

Here is where I ended up with settings:

Roll Torque: 85% SV32
Roll Sensitivity: 8
Max Bank: 25
Turn Rate Limit: 0.0
Absolutely no slipping during todays tests

Pitch Torque: 75% SV42
Pitch Sensitivity: 13
Vertical Speed: 500
Absolutely no slipping during todays tests

I flew HDG, TRK and NAV modes from my new Aera 510. I also tested climbs/decents to a new altitude both straight and while turning to new hdgs all under full AP control.

Weather today was a mixed bag depending on altitude and I used all the various modes in both light chop and glass smooth and a few moderate bumps.

I must say that I am totally impressed with the AP so far. I really did not expect it to work this well. Altitude hold in straight and level is +- 5 in smooth and 10 in the chop and bumps.

In the turns it is +-10 most of the time but every once in a while it might be +-15. Most pilots are not that good hand flying an RV.

HDG mode follows the compass. Not much more you can say about that. TRK and NAV modes are dead on the money. Once the AP joins the course on NAV mode the Aera reports 0.0 cross track error 99% of the time. No twitchiness.

Long straight and level in smooth air and the thing is dead on. It will put you to sleep.

The pitch trim annunciation works as advertised and never left me with a wild ride on disconnecting the AP.

Climbs and decents were very close to my 500fpm rate setting and worked as one would expect. Occassionally there was some slight back and forth as the plane settled in on the altitude but overall I was surprised.

The AP does not remove the "RV wiggle" that they all seem to have in the bumps and I never expected it to.

I never did get the "Nav Source Lost" message that some get with the X96 series of gps.

I did manage to confuse the AP in one case and I do not know if it was the AP's fault or the GPS's....I was in NAV mode following a flight plan and was on a course to a waypoint that had the next course 175? to the right of the original course and when I crossed the waypoint, the AP turned left instead of right and turned about 90? left from the original course and rolled level. This went on for about 1/2 mile and then the AP turned to intercept the next course. Not sure what happened there. I will need to test that again and see if I can get it to repeat.

I did test the emergency 180? turn feature and it works great.

Now for the way I have the intefaces set up:

I have an HS34 and an AP74...

I have the Value knob on the HS34 set for first action to set baro

The Heading knob on the HS34 always adjust the HDG/TRK bug

The Course knob on the HS34 always adjust the HSI course

The Value knob on the AP74 is set for first action to set the ALT bug

I have the AP74 set to sync bugs on ARM and to clear the modes armed on disengage.

This works more than great!!! I have dedicated knobs for Baro, HGD/TRK Bug, Course, and ALT Bug!!

With the AP74 options selected, I can ARM the mode I want to engage, either leave the bugs alone and engage the AP or I can ARM the mode I want and then tweak the bugs to whatever I want the AP to do when I engage the AP. Works great and would be great for approaches.

I am sure I will find some more flaws in this thing somewhere but the first impressions are good....

RV10inOz
05-21-2010, 06:09 AM
I did manage to confuse the AP in one case and I do not know if it was the AP's fault or the GPS's....I was in NAV mode following a flight plan and was on a course to a waypoint that had the next course 175° to the right of the original course and when I crossed the waypoint, the AP turned left instead of right and turned about 90° left from the original course and rolled level. This went on for about 1/2 mile and then the AP turned to intercept the next course. Not sure what happened there. I will need to test that again and see if I can get it to repeat.

I have seen the same weird thing myself for some bizzare reason. Last time was in IMC flying the RNAV into Hobart Tasmania, maybe I was loading the stick up by hand to the right, as I was doing the vertical nav myself leaving the tracking to the A/P. It seemed to want to do a right orbit to get back on track.....and I was 2 dots right of track by then, and with a Qantas B737 up my butt a right orbit was not going to be a good look, so I disconnected and hand flew the last part.

I did have a strong crosswind from the right and the a/c was cocked to the right also. Not sure what this may have induced. Will try to replicate some day. Dynon can not fathom it as the A/P only follows the GPS commands of fly left or fly right. the GPS is a GNS530W.

Any ideas appreciated.

DB:cool:

PS other than that its been a really great A/P.

Brantel
05-21-2010, 11:01 AM
I thought I would put a picture to my words on how I confused either the AP got confused or the GPS did one or the other.....

I was flying a two leg flight plan with the Aera 510 doing the driving and the change in course was extreme....Something like 175°.

Here is what happened:

http://i50.tinypic.com/6hl277.jpg

rvmills
05-21-2010, 11:47 PM
Brian,

Did the AP stay in NAV and make all 4 of those course corrections hands-off?

(By four, I mean the initial slight left turn, the hard left to the SW, the hard left to the ENE, and then the new SE course intercept.)

I'll try to replicate it next week when I get home (wx and a kiddo B-day party tomorrow, then a 3 day trip). Back atcha when I give it a go.

It is a pretty radical turn...practically speaking, seems only a hold or procedure turn would require a such a course reversal, and they would have intermediate turns (ie, direct, parallel or teardrop)...but of course, never say never, it could happen (and I know you are just testing the APs capabilities and limitations...it'll be fun to do more of the same!) You know, it would also be interesting to see how the AP reacted if you engaged a direct to an airport behind you. Say you were on that magenta course to 3A2 as your destination, and the second course was not it the flight plan. Then, say two miles from 3A2 you hit direct to MOR and enter. Same basic angle of course change...what would it do? I may try that too (different waypoints, of course!), just for grins.

Brings up a side-question on holds and proc turns with a 430 or similar. I have only a 396 and am wondering how an IFR GPS sets up and flies holds and proc turns. Do you as a pilot have to manage the turns and intercepts, or does it draw the hold and do the appropriate pattern entry? I know how the FMC at work does it, and wondering how it compares, given the advanced tech that is so readily available in the gear for our (RV) airplanes (and quite often better than what is in the bigger iron)! Just wunderin'!

Cheers,
Bob

Brantel
05-22-2010, 08:30 AM
Bob,

The 430W will do holds and proceedure turns hands off.. The 430 won't do it. You must be using GPSS for it to work on the 430W. With GPSS, the GPS is really flying the Airplane since the GPS is actually sending bank commands to the AP.

Those of us using portables are stuck handling the turns ourselves but this is easy with the AP74/HS34...just twist the knobs!

RV383
05-22-2010, 11:03 AM
I had quite good performance with the AP performance in TRK/NAV mode, from the G496 or G430W driving it. I have the -10 with dynon roll mount for the servo, but had to build the pitch mount bracket as it was not available when installed. I set it with a longer throw and the arm has more travel, and it has the torq/sens settings backed off and even in heavy chop and some pretty good up/down drafts on a recent 2 hour flight over the mountains it held altitude at a max of 40ft and right on for smooth air/ light chop. I would have to say the HDG mode is much better with the newest software release and was useless before. It might be nice if the EFIS mag compass tape could use a GPS signal to use that info for the magnetic heading, and eliminate the electronic compass, or have an option to do so.

Brantel
05-22-2010, 01:30 PM
Gps ground track and the magnetic hdg will never agree unless there is no wind.

ATC expects you to be flying a hdg not a ground track when they are vectoring you....

If you use the TRK mode, you will be flying ground track.

rvmills
05-22-2010, 02:54 PM
Roger all Brian...makes sense...sounds like nice gear, that 430W!

And twisting knobs is not so bad...one of the six T's, right! Not that we'd be doing procedure turns and holding with a portable anyway! :p

And concur with you on the mag heading thing...to get that from a GPS, it'd have to derive it from the track and the wind...too much math there! For RV383, I agree that after 5.3 and setting the turn rate setting to zero, the heading control is much improved, probably ATC/IFR-ready, though I still want to play more with it to watch those roll-outs.

Brian, a couple of my earlier Q's probably got buried in my blather...do you see any early roll-outs in HDG mode and then a slow last 20 or so degrees of turn? And did the AP do all those turns hands-off in the 175 deg turn event? Will test more next week and let ya know what I see. How's Phase I coming...having a blast? :)

Cheers,
Bob

Brantel
05-22-2010, 04:41 PM
Brian, a couple of my earlier Q's probably got buried in my blather...do you see any early roll-outs in HDG mode and then a slow last 20 or so degrees of turn? And did the AP do all those turns hands-off in the 175 deg turn event? Will test more next week and let ya know what I see. How's Phase I coming...having a blast? :)

Cheers,
Bob

Hey Bob,

I did not notice any early roll outs and then slowness. I will double check this when I fly again...

On my confused AP or GPS....Yep, NAV mode was enabled the entire time. Eventually the thing woke up and rejoined the second course.... I am going to try and recreate this on the next flight. Dynon wants a copy of the logs if I can get it to do it again...

Phase I is going slower than I would like since the weather has not been cooperating with my schedule...I am over half way thru but I hope to get several more hours in this next week. The plane is awesome!!! I fixed a few oil leaks today and gave the FWF a real good look for issues.

I might have an issue with my A210 as last flight it seemed that the reciever lost some sensitivity as I had to be on top of the airports to get the AWOS and noticed that I was having problems with hearing people. After the flight I checked the SWR and it was good so I am not sure what was going on???

rvator51
05-22-2010, 05:16 PM
Hi Brantel,
I have seen the same problem on my A210. I found that if I turn it off, then turn it back on, the reception is back to normal for a time. I sent it back to get checked out, but they said they could find nothing wrong. But it is still doing it. Be interesting if my fix works for you too.

Brantel
05-23-2010, 05:31 AM
Reply about the A210 issue in this thread:

http://www.vansairforce.com/community/showthread.php?t=58259

Brantel
05-23-2010, 04:05 PM
Today I flew 1.5 in moderate (for me anyway) turbulance and the AP worked ok. I did not tweak anything I was mostly trying out my new Zaon XRX and the Aera 510...

Brantel
05-29-2010, 03:53 PM
The nav source lost bug is still there with the Aera and version 5.3.....had this happen about 10 times on a two hour flight. Seems to be no rhyme or reason to it... The HSI never waivers during these events...

dedgemon
05-29-2010, 05:44 PM
nav source lost at random times. Can't even tell it's happened if you don't see the message.

L.Adamson
05-29-2010, 06:19 PM
nav source lost at random times. Can't even tell it's happened if you don't see the message.

I've never seen any type of lost messages on my 696. Have been running it for 1 1/2 years.

L.Adamson -- RV6A

Brantel
05-29-2010, 08:09 PM
You won't see it on your 696.. You won't see it at all unless you are running the Dynon AP.

This message shows up on the Dynon EFIS if the AP downgrades the mode from NAV to TRK/HDG. The AP thinks it is losing the NAV source from the GPS....

I've never seen any type of lost messages on my 696. Have been running it for 1 1/2 years.

L.Adamson -- RV6A

rvmills
05-30-2010, 01:47 AM
I'm still seeing the NAV SRC Lost messages as well. Mine always defaults to TRK, and I agree, the warning is all you see...no flight path changes (unless you get to a NAV course turn point, then it'll miss the turn if you're still in TRK).

The data loss appears to be just moementary, for as soon as I see the message, I can just hit NAV, and it reengages in that mode and trucks along. I've seen posts on the Dynon forum (and Brian I know you are familiar with this part...I post it for other/future readers) that say its due to stale GPS data being rejected by the AP...something along those lines.

It was reportaedly addressed on a recent FW update (can't remember which). After that update the losses did seem to decrease in frequency, but they are still there...sometimes more frequent, sometimes less. Seems to be a timing thing, just seems to depend on when the data is sent to the AP, and whether the GPS data is good or "old". I do notice that sometimes it happens when I update a direct-to course and execute, such as when I'm changing the point I'm flying to, or finishing up a deviation, then want to go direct to the next waypoint. Just an observation.

It's a minor annoyance, but it would be nice to see it go away. Interesting to hear its on the Aera as well as the x96 line. I'll bet you've already put that on their forum! ;) I know Dynon continues to work it.

Cheers,
Bob

flickroll
05-30-2010, 04:58 AM
Back when I had a Dynon panel and AP, as I remember the only times I'd lose the 696 was when I was doing something with the 696. Zooming, going into menus, etc. I don't think I ever had it just tooling along with no input from me. Wouldn't swear to it though. My experiences with losing the 696 were very infrequent. The last software I used was 5.2

RV10inOz
05-30-2010, 05:38 AM
if you have ARINC429 its VERY stable and only if you lose RAIM and go to DR mode on the GNS530/430 does it resort to HDG mode. Otherwise the 429 link and hence A/P is always rock solid.

Brantel
05-30-2010, 06:37 AM
Yep this issue seems to exist with any brand GPS that is using NMEA serial data to communicate to the Dynon. I have found no real association with my interaction with the GPS and when this thing decides to fail down to Trk or Nav.

I flew another 1.5 last evening and it never failed down at all.....

647jc
05-31-2010, 06:17 AM
Yep, lost NAV source a couple times the other day. Apparently the new firmware has not corrected the problem. Also, was requested an audible warning be added when this occurs which didn't seem to get put into the firmware either. Using an Avmap IV and EFIS 100.

CuriousGeorge
06-05-2010, 08:15 AM
Ok, I'm about to pull the trigger on an a/p. TT has the experience and a great product, but it looks like $4,000 for 2 axis without a display, or $4,200 with the new EFIS, but it's big so a complete panel re-do would be encessary.

Dynon has a great display and it fits nicely, also about $4,000 but it has a checkered (at best) history. If the 5.3 firmware fixes the problems so many have been having, I like it. If it's never going to work satisfactorily, I'd rather spend the extra bucks for the TT. This might be a "you get what you pay for" issue.

This thread has been a huge help, so thanks for all who weighed in. I've read lots of complaints on other threads about the Dynon a/p with few contradictions, but all prior to 5.3 coming out.

Are there any other guys out there with Dynon 5.3 experience? Beta testers? Anyone? Anyone? Bueller?

Thanks --


George

Brantel
06-05-2010, 08:31 PM
5.3 is much better in roll or so it seems to me (based on reports of prior versions). I could not ask for a better roll AP.

Pitch still has a few quirks but they are working on it. I would expect the next release to be much better in pitch.

The Dynon AP is a very advanced system. The servo's are smart and talk back to the EFIS to let it know things it needs to know about the servo and its status. Most other (if not all Experimental models except the Trio Gold servos) autopilots have dumb servos that do not communicate back to the controller. The Dynon servos actually have processors in them.

That being said, the possibilities for this system is only limited to the time the resources at Dynon have to spend on it.

The AP was a little slow out of the gate and its growing pains fell right in the middle of the release of the Skyview. The Skyview is turning out to be a sight to behold and is catching up in spades to the competition so most of the resources at Dynon have been busy.

I would not try to talk anyone into any brand AP...I just state the facts and it is up to the individual to make up their own mind. You can't go wrong in my opinion with what is out there right now TT, Trio or Dynon. Just make sure whatever you pick will do (features, connectivity, modes, etc) what you think it will so you are not disappointed....

Sam Buchanan
06-05-2010, 09:14 PM
The Dynon AP is a very advanced system. The servo's are smart and talk back to the EFIS to let it know things it needs to know about the servo and its status. Most other (if not all Experimental models) autopilots have dumb servos that do not communicate back to the controller. The Dynon servos actually have processors in them.

Just to make sure the record is correct--The Trio Avionics Gold servos communicate with the control head. Lots of talkin' back and forth goin' on with the Trio system; load on servo, G's being generated, handshaking, etc, etc, quite advanced stuff.

RV10inOz
06-06-2010, 03:39 AM
And a little known FACT....Trio are struggling with the servo on the RV-10 elevator.

Forces are an issue! Dynon have a fix, which I am testing and possibly the only tester.....don't ask why...coz I won't say, but its really the -10 that needs it. Its not an A/P problem, and its a problem for others too, even if they do not know it possibly.

The Dynon A/P we are finding rock solid, mind you ARINC 429 is the way to go, serial comms is an issue even for True Trak....we have an RV guru down under who has the same drop out with a Garmin 296 and a TT A/P so most of what your hear applies to others too.

George..... I would not like to admit being biased, but after a far better run than I expected I have to say go the Dynon. Given the number of D10/100 etc out there and the new A/P product, you will have a high number of initial problems, most of which are user related. The Dynon folk have made improvements and are working on some more, some I have been apart of to a small extent, so I know better things are to come.

Can't beat it.

DB

Tim 8-A
06-06-2010, 05:44 AM
This thread has been a huge help, so thanks for all who weighed in. I've read lots of complaints on other threads about the Dynon a/p with few contradictions, but all prior to 5.3 coming out.

Are there any other guys out there with Dynon 5.3 experience? Beta testers? Anyone? Anyone? Bueller?
Thanks --
George[/QUOTE]


I have been using the Dynon AP for about a year,and any issues I had with it before have been addressed with the 5.3 update.
I am converting my panel for IFR and I am staying with the Dynon AP.

Brantel
06-06-2010, 05:52 AM
Sam,

You are correct... I forgot about that one. I edited my original post....

Just to make sure the record is correct--The Trio Avionics Gold servos communicate with the control head. Lots of talkin' back and forth goin' on with the Trio system; load on servo, G's being generated, handshaking, etc, etc, quite advanced stuff.

Rainier Lamers
06-07-2010, 01:47 AM
Just to make sure the record is correct--The Trio Avionics Gold servos communicate with the control head. Lots of talkin' back and forth goin' on with the Trio system; load on servo, G's being generated, handshaking, etc, etc, quite advanced stuff.

No, not entirely correct.
The Trio servos do not measure the load on the servo arm. They don't know anything about G forces (the control head does that). The Trio servo reports the position of the arm, if the clutch is slipping or if the servo arm has moved outside it's available position measurement limits. That is all the control head needs to know.
Yes, it's a good servo nevertheless and for this reason supported by our autopilot systems.

As far as I am aware, the MGL Avionics servos that are currently being put into production are the only mainstream servos around that can measure actual forces on the arm while engaged and working without this needing extra external hardware (like load cells).
I was using this on Saturday during flight to develop our automatic trim algorithms. There is only one sure fire way to do automatic trim - and that is to measure actual forces acting on the stick (as you would as pilot), all other methods guess trim based on previous AP activity - and that quickly goes out the window if there is turbulence involved and does not work well on many aircraft types.

Rainier
CEO MGL Avionics

Rainier Lamers
06-07-2010, 01:51 AM
And a little known FACT....Trio are struggling with the servo on the RV-10 elevator.

DB

I dunno, but we have several RV10 aircraft flying with Trio servos on the pitch just fine (on the MGL AP), are you sure ?

Rainier
CEO MGL Avionics

RV10inOz
06-07-2010, 05:56 AM
Yes actually.

Tru Trak and Dynon also have found the same.

Direct exposure to both the Trio and Dynon problems, and the fact Tru Trak have been onto it before suggests there is more to it than meets the eye!

Given you are close to the action you will probably know the results before I do.

DB;)

Rainier Lamers
06-07-2010, 07:53 AM
Yes actually.

Tru Trak and Dynon also have found the same.

Direct exposure to both the Trio and Dynon problems, and the fact Tru Trak have been onto it before suggests there is more to it than meets the eye!

Given you are close to the action you will probably know the results before I do.

DB;)

I am directly aware of two RV-10 units flying the Trio servos and have good reviews on both. One of the pilots involved gave a rather glowing review of the AP (and the servo) performance on the Stratomaster list not long ago.
Can you elaborate a bit on what you mean by "force related" ?

I think I can say with some confidence that whatever the issue may be, it is not related to the servo - the Trio is quite a solid performer in my experience.

I am of course aware of the ease of which an AP can be matched perfectly to certain aicraft yet fail miserably on another. The RV-10 however is not an aircraft that I would classify as difficult to fly for an AP. The most difficult aircraft I have so far been involved with is a GP-4 and as far as I know, no AP has ever been able to fly this aircraft (except ours of course, but only properly after a few firmware updates and head scratching).

Rainier
CEO MGL Avionics

dynonsupport
06-07-2010, 12:09 PM
The Dynon servos measure the force they are exerting, as well as the position, while they are engaged. They do this without "load cells" or extra hardware as well. We currently use this for pitch trim indications and have done this since we first shipped the AP.

On another topic, SkyView is getting enhanced pitch performance in the 2.5 release which should be out shortly, and this will of course roll into the D10/D100 products as well. We are hearing this is doing as much for pitch as 5.3 did for roll, especially in turbulence.

Brantel
06-07-2010, 12:21 PM
Thanks for the update Dynon!

RV10inOz
06-07-2010, 11:18 PM
The amount of force delivered to the elevator can be an issue for the RV-10.

The issue you get is hunting around the set point. Its not that there is anything wrong with the servo from Trio/Tru Trak or Dynon, its the amount of force required and when in turbulence the sensitivity of the system.

My belief with what I have seen so far is the control resolution and the ability to deliver sufficient torque when needed.

The RV10 has a rather high load elevator unless perfectly trimmed, and its very powerful also, it needs to be at slow speeds, however at high speeds it is also very responsive. Small movement = lots of result.

It may be that some of us are very fussy and have picked up on this, but its not just an RV10 & Dynon phenomenon, others have the same symptom with different installations it seems.

Cheers

DB

Rainier Lamers
06-08-2010, 08:45 AM
The Dynon servos measure the force they are exerting, as well as the position, while they are engaged. They do this without "load cells" or extra hardware as well.

I stand corrected :o

Rainier
CEO MGL Avionics

CuriousGeorge
06-08-2010, 01:57 PM
I was gone for 3 days and came back to lots of good info. Thanks to everyone who weighed in.

It looks like there are several fine products out there, which is great for us consumers. It sounds like Dynon's improvements are around the corner, and thanks to Dynonsupport for weighing in on that. I'm glad to see some satisfied Dynon owners piping in as well. TT still has the historical edge, and their new EFIS package is attractive while being competitive with teh D-10A package. Competition is good.

I'm not a big fan of troubleshooting and running down software problems, but if the little Dynon D10A fits nicely into my panel without much effort, that's a plus. Final decision making to go. (I'm sure you're all on the edge of your seats wondering...)

FWIW, the autopilot I use at work requires finesse and attention to operate smoothly, does stupid and annoying things on its own, speed up to 15 kias off, easily prone to VNAV errors either pilot induced or on its own, does more weird stuff when its speed/altitude parameters are exceeded, and surely cost probably 100times more the most expensive of our units. Hardly a set it and forget it unit. How it got part 121 certified when it commonly performs below private pilot standards, I don't know. Gotta love how good things are when the gov't gets involved.

Anyway, I'm looking forward to whatever system I end up with, and the info shared has been a real help. I'll pass on my review when the time comes for future researchers like me.


George

Rainier Lamers
06-09-2010, 01:36 AM
IFWIW, the autopilot I use at work requires finesse and attention to operate smoothly, does stupid and annoying things on its own, speed up to 15 kias off, easily prone to VNAV errors either pilot induced or on its own, does more weird stuff when its speed/altitude parameters are exceeded, and surely cost probably 100times more the most expensive of our units. Hardly a set it and forget it unit. How it got part 121 certified when it commonly performs below private pilot standards, I don't know. Gotta love how good things are when the gov't gets involved.

George

You have just, in a nutshell, described the advantages of uncertified EFIS systems and autopilots.

Uncertified means fast development. Example: Since I design all the MGL systems myself, if there is an issue with the AP reported, I simply climb into my trusty aircraft and see if I can replicate the problem or at least get a hint. Usualy, in this case I have my laptop with me and I will tweak the software as I go along. This has been ongoing since we started including an autopilot. I learn as I go and the result is obvious - it just gets better and better. If I am happy with an improvement, it goes into the release which happens on a frequent bases (sometimes as beta if I need input from others before making a general release). Nothing to sign off, nobody to speak to, nobody to pay, nobody to take for lunch, nobody that needs a bribe. Simple, effective, fast.

The same (or similar) happens with all the players out there and the result is what you see - magnificant EFIS systems that were science fiction a couple of years ago at rock bottom prices.

Competition helps greatly - we all watch each other like hawks and there is little chance anyone will get ahead. I have predicted years ago that EFIS systems will become not only very powerful but also much more similar in capability and price (pretty obvious of course) and this is happening now and it's by no means over and done yet.

Designing and making EFIS systems must be one of the great jobs out there (I get paid for flying - beat that !) and I for one look forward every day to get to work...

Rainier
CEO MGL Avionics

Brantel
06-17-2010, 12:16 PM
While I cannot go into any detail, I can assure those that are interested in Dynon AP's performance, that Dynon is working hard on making it better, much better!!!! ;)

As always, you make up your own mind as to what AP you want to use.....My post are just based on my experience with the Dynon system. Yours may vary greatly due to the huge number of variables involved...

RV10inOz
06-18-2010, 01:10 AM
Have to second that. I cant say any more either...coz I just do not know what they are doing exactly but I can't wait to test the new version as I believe it will be smoothing out the A/P quite well.

Dynon are doing a good job!

DB:)

CuriousGeorge
06-28-2010, 10:58 AM
For those with Dynon experience, think an SV-32 servo is enough for an RV-3?

And... I spent the morning searching for a PC-DI2BK data cable for my Lowrance 2000C. Even the posts here in the recent past came up empty. Anyone know of a source for them?

Thanks --

CuriousGeorge
06-28-2010, 11:57 AM
Update to the cable question - Lowrance and some other posts I just found said it's a NDC-2 101-36 cable. Same thing, if anyone has a recent source...

dedgemon
06-30-2010, 07:42 AM
For those with Dynon experience, think an SV-32 servo is enough for an RV-3?

And... I spent the morning searching for a PC-DI2BK data cable for my Lowrance 2000C. Even the posts here in the recent past came up empty. Anyone know of a source for them?

Thanks --

George,
The SV-32 is plenty for my '8. I would think that the 3's forces would be lower. Probably much lower.

n504tw
06-30-2010, 11:19 AM
Same seller in the UK showing two cables. Check with them to make certain they are 101-36, but it appears they are.

gasman
06-30-2010, 11:23 AM
Update to the cable question - Lowrance and some other posts I just found said it's a NDC-2 101-36 cable. Same thing, if anyone has a recent source...Here is some info from Sam. The 100 cable is the same as the 1000 and the 2000C................

http://www.vansairforce.com/community/showpost.php?p=51419&postcount=7


btw..... I was next in line...........:( for 8TM......... enjoy

CuriousGeorge
06-30-2010, 12:21 PM
Thanks for that info, Gasman - I think I found a cord on ebay. Hope it comes and is right, but it looks good. Lots of work for a $15 cable!

Sorry for you that I beat you to 8TM... but yes, I'm thrilled to have the plane. I was number 2 actually, number 1 had eaten too many donuts and couldn't comfortably fit in it! For once having a skinny non-football body paid off. Hope you find your bird soon...

CuriousGeorge
06-30-2010, 12:24 PM
...and thanks David and Gary.

Buggsy2
07-14-2010, 04:50 AM
...All of these comments may change when I get more time on the unit in different turbulence conditions. Time will tell. Right now I am happy as a clam that it works as well as it does with little to no tuning required on my end. You can't beat the price point to enter into an advanced feature set dual axis AP...More to come later!

Any more news? This topic is quite important to me and many others as I'm sure you know!

Brantel
07-14-2010, 05:26 AM
Since I am now running Alpha firmware I cannot comment on current AP performance.

Rest assured that Dynon is working hard at improving the performance of the pitch axis. That's all I can say about that..

Roll axis has been awesome since 5.3 was released.....

RV10inOz
07-14-2010, 08:24 PM
Since I am now running Alpha firmware I cannot comment on current AP performance.

Rest assured that Dynon is working hard at improving the performance of the pitch axis. That's all I can say about that..

Roll axis has been awesome since 5.3 was released.....
__________________

Thats a strange comment for a NON comment :D

I hope to Beta Test the new version in the Dash 10. Its going to be interesting to see how it goes, I expect great things to come shortly. I hope to do this pre Oshkosh, otherwise the Beta test will be delayed a few weeks.

DB:cool:

dynonsupport
07-15-2010, 10:26 AM
We have updated and released the improved pitch axis in the 2.5 software for SkyView and are working on 5.4 for the D100/D10A/D180 products. So anyone flying SkyView would be able to give their opinion. I'm biased, for sure, but in my experience, the whole AP is a huge improvement from just a few months ago. We've learned a lot about controlling an airplane in the last 18 months.

Brantel
07-15-2010, 10:54 AM
David, Bob,

Since Dynon decided to talk about it....someone with a keen eye could take a look at the AP instructions in the manuals for the Skyview and notice that there may be some differences in key areas that could give someone an idea on where they "might" see some changes that possibly could be in the future for the legacy product's AP....;)

Any more news? This topic is quite important to me and many others as I'm sure you know!


Thats a strange comment for a NON comment :D

I hope to Beta Test the new version in the Dash 10. Its going to be interesting to see how it goes, I expect great things to come shortly. I hope to do this pre Oshkosh, otherwise the Beta test will be delayed a few weeks.

DB:cool:

We have updated and released the improved pitch axis in the 2.5 software for SkyView and are working on 5.4 for the D100/D10A/D180 products. So anyone flying SkyView would be able to give their opinion. I'm biased, for sure, but in my experience, the whole AP is a huge improvement from just a few months ago. We've learned a lot about controlling an airplane in the last 18 months.

rvator51
07-15-2010, 12:10 PM
With as many additional settings as were added to the pitch axis in Skyview, you should be able to fine tune your plane to your hearts content!

rvmills
07-15-2010, 01:32 PM
I'm likin' what I'm readin'! Thanks for the heads-up Brian (and DS)!

Will stop by the Dynon booth at OSH to say hi, say thanks for the continued support, and to check out all the stuff I know I'm gonna wish I had!

And I just know the programmers are gonna make a breakthrough and develop an SV plug-in for the legacy EFIS systems...or is that what you're Alpha testing Brian!? :D (I'm kiddin'...happy camper here!)

Cheers,
Bob