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amekler
01-08-2012, 03:46 AM
Rob,
I have noticied I lose 100 ft or more while in a turn and once wings level altitude corrrects. Is this an adjustment for this?
Alan

Rob Hickman
01-08-2012, 12:08 PM
The Static Lag adjsutment in the AP can make this worse, you might try lowering it.

Increasing the EFIS ALT gain should also help, if it gets too high it will overshoot when moving to the altitude bug.

amekler
01-08-2012, 02:04 PM
The Static Lag adjsutment in the AP can make this worse, you might try lowering it.

Increasing the EFIS ALT gain should also help, if it gets too high it will overshoot when moving to the altitude bug.

Rob,
ALT GAIN currently set to 5.0 Static Lag set to 2
What numbers do you suggest?
Alan

Rob Hickman
01-08-2012, 05:36 PM
Your only choice for the static lag is 0,1, or 2

amekler
01-08-2012, 06:09 PM
ok will try it.
alan

rshannon
12-16-2012, 06:22 PM
Alan, would appreciate knowing how this issue worked out for you. Thanks.

amekler
12-17-2012, 02:26 AM
Ron,
despite trying what was suggested i still loose altitude in a turn and it corrects.
alan

Rob Hickman
12-17-2012, 10:05 AM
Did the static lag make any difference?

How much are you losing?

Do you have autotrim?

amekler
12-17-2012, 11:26 AM
did not notice any difference with the static lag. usually lose 100 ft in a turn. it corrects after the turn but not in the turn???
yes have autotrim.
alan

TrutrakTech
12-17-2012, 02:29 PM
Alan, what version of software do you have in the AP? What kind of bank angle are you seeing during turns?

amekler
12-17-2012, 04:46 PM
Lucas,
I will check. I had the autopilot upgraded to the advanced flight model a year or so ago.
Bank angle seems to be about standard rate.
Alan

NoahF
01-12-2013, 08:14 AM
I have the same problem. Static Lag was 5, now set to 4, no change. No autotrim.

Alan, were you able to resolve this??

Rob Hickman
01-12-2013, 10:21 AM
I have software version 2.53 in the AP in my RV-10 and the static log only goes to (0-4)

1. What happens if you set it to 1, does it get better?

2. Have you tried increasing the ALT gain in the EFIS ?

3. Have you tried increasing the VERT Activity in the AP?

amekler
01-13-2013, 02:15 PM
Still haven't had a chance to improve on the altitude loss in a turn. will check my software edition.
alan

amekler
01-14-2013, 06:56 PM
Lucas,
I have version 2.44.
Alan

amekler
01-14-2013, 07:05 PM
rob,
i have version 2.44
what does 2.53 have different?
why aren't we informed of new software updates for the AP?
Alan

rleffler
01-15-2013, 06:24 AM
Alan,

I suspect the reason is that it usually requires sending the AP back to Trutrak. I don't think we have the ability to upgrade the software on the AP head. My experience is that Lucas will recommend upgrading if you are experiencing a known issue. Being an IT guy myself, publishing known issues is a double edge sword. While I prefer to see list of improvements/fixes for each release, I understand why some companies don't publish that information.

bob

amekler
01-15-2013, 09:28 AM
Bob.
I have already had my AP upgraded twice so I know its a pain but if there is a better version its worth doing.
Alan

Rob Hickman
01-16-2013, 07:10 PM
I will have to check with TruTrak.

amekler
01-16-2013, 07:54 PM
rob,
thanks,
alan

TrutrakTech
01-24-2013, 09:15 AM
An update wouldn't hurt. Call, PM or email me with your serial number. The last record I have under your name shows version 2.30 on a DII VSGV. I'll set you up with an RMA to send it in for update. Let me know. Thanks!

amekler
01-24-2013, 01:41 PM
thanks.
alan

jkgoblue
01-25-2013, 03:47 PM
Is there any material from TruTrak or AFS that describe the differences in the software versions? I have 2.45 now. Should I update?

amekler
01-26-2013, 04:23 AM
John,
I would check with Lucas at TruTrak.
I'm sending mine in for the update.
Alan

amekler
03-09-2013, 05:44 PM
i upgraded to 2.53
i see no difference. still lose altitude in a turn and descents go 50 to 60 feet below set altitude and then slowly correct. in level altitude i show about 40 feet lower than set altitude.
have tried playing with vert activity and static lag and only made it worse.
maybe i'll just have to live with it???
Alan

Rob Hickman
03-10-2013, 10:29 AM
What is the vertical speed command showing when you are level and 40ft low from the check list page?

amekler
03-10-2013, 11:55 AM
it says 120
alan

amekler
03-10-2013, 12:00 PM
static lag set to 1
2 made it worse
alan

Rob Hickman
03-10-2013, 03:28 PM
That means that the EFIS is telling the AP to climb at 120 Ft/min. Do you have the ALT gain in the EFIS set to 3?

AP V Speed = EFIS_ALT_GAIN x ALT_ERROR

3 x 40 (FT Error) = 120 FT/Min climb

In my RV-10 I have the ALT Gain set to 5 and with a 40 FT error I get a 200 FT/Min climb.


5 x 40 (FT Error) = 200 FT/Min climb

amekler
03-10-2013, 04:41 PM
rob,
No. I originally had the alt gain at 5 and had increased it to 9 in hopes of having it help. Why does the altitude stay 30-40 feet below the set altitude despite the EFIS commanding the AP to climb?
I saw 200 after increasing from 5 to 9.
Alan

ps AP is set to 6 vertical activity static lag 1

Rob Hickman
03-10-2013, 06:29 PM
If you have the EFIS ALT gain set to 9 you should see this:

V Speed = 9 x 40 FT

V Speed = 360 Ft/Min

Double check the EFIS ALT gain, I don't think it could possibly stay at 40FT low with an EFIS ALT Gain of 5 or more.

amekler
03-11-2013, 01:15 AM
ok will check on my next flight
should i reset EFIS ALT GAIN to 5?
Alan

Tom Martin
03-11-2013, 05:48 AM
A year ago now I send my servos in for the upgraded safety nut on the main arm. The safety nut replaced the original screw. I installed the servo and all seemed well. During the summer, and an upgrade from an ADI II to the new EFFIS driven autopilot I experienced a lot of small roll issues. One of the problems that I experienced was that in turns the autopilot had trouble holding altitude. I chased this issue ALL summer, numerous tests, numerous settings, and it seemed to get worse until it failed. When describing the problem to Lucas he told me that they had had a manufacturing issue last winter in some of the upgraded servos. I would not have thought that the altitude control would be affected by the roll servo but it most definitely was. I have not had any altitude issues in turns since the roll servo was repaired.
It would have been nice if the company had sent out an email to those whose servos may have been affected. This would have saved me hours of testing and also saved one ILS approach that went south on me when the system did not hold course or altitude on a turn to final in IMC conditions.

amekler
03-11-2013, 08:15 AM
tom,
interesting. my servos are from 2009. i replaced the safety nut about 3 years ago.maybe i should replace my roll servo.
Lucas what do you sugest?
Alan

TrutrakTech
03-11-2013, 09:45 AM
Alan, your servos are most likely fine. Tom's servo was serviced in early 2012. His problem in the servo was caused by a broken roll pin inside the gear box. We identified an improperly sized hole in the servo shaft which allowed the roll pin to break. Unfortunately there is no way to track the individual servo shafts that are installed. The supplier has been changed since that time.

How much altitude is being lost in a turn?

amekler
03-11-2013, 11:11 AM
100 feet.
alan

TrutrakTech
03-11-2013, 11:21 AM
What is your GPSS gain setting?

amekler
03-11-2013, 12:45 PM
16
The loss seems mostly when in heading mode on the efis and i turn 90 degrees or more.
Alan

amekler
03-11-2013, 05:02 PM
flew today in smooth air. Altitude read about 20-30 feet low with EFIS ALT gain set to 10. This was better than with it set to 5.
What I didn't like was in descents I would bust through the altitude set by 80-100 feet before slowly correcting .
Alan

Rob Hickman
03-11-2013, 05:24 PM
ALT Gain of 10 is way to high, It should be hunting up and down like mad with a gain of 10?

V_SPEED = 10 (gain) x 20 FT

= 200 Ft/min commanded climb rate

Was it showing a 200 FT/min commanded climb on the check list page?

Are you adjusting this on the screen that is wired to the ARINC module?

amekler
03-11-2013, 05:28 PM
yes it was showing 200 varying from 120-220.
it was not hunting up and down, in fact it was quite steady at 20 feet below set altitude.
what do you recommend?
alan

Rob Hickman
03-11-2013, 05:34 PM
We need to find out from TruTrak why it is not climbing when we are sending a command of 120 to 220

amekler
03-11-2013, 05:56 PM
yes thats what i don't understand. if the efis commands a 120-200 foot /min climb why doesn't it climb back to the set altitude and see a 0 ft/min/
also i don't like it busting altitudes in a descent.
Alan

Rob Hickman
03-11-2013, 07:25 PM
If the ALT gain is too high it will bust altitudes.... Put it back at 5.

amekler
03-12-2013, 01:15 AM
ok will put it back to 5.
alan

Rob Hickman
03-12-2013, 09:03 AM
These are the settings from my RV-10

AP VRT Activity 4 ; MICROACTIVITY 2
EFIS ALT Gain 5

Video using these settings:

http://www.youtube.com/watch?v=gQfEVvIk_MQ

amekler
03-12-2013, 10:49 AM
Rob,
these are my current settings

static lag 1- should i change it to 0?
vertical activity 6- should i change it to 4 ?
microactivity 0- should i change it to 2?
alt gain 5- as you suggested

Alan

amekler
03-16-2013, 03:23 PM
Rob,
Flew today with your AP/EFIS settings. Lost about 50 feet in heading mode with a 90 degree turn. Efis showed between 100 and 330 ft/min.
in level flight altitude was about 20-30 feet low with efis saying 100-120 feet per minute.
This is a bit better than what I had before.
Alan

amekler
05-18-2013, 02:17 PM
Rob,Lucas
I
have noticed that my altitude usually runs 30-40 feet lower(always lower) than what is in the EFIS. When I hit check it shows the EFIS is telling the AP to climb at 120-170 ft/ min but nothing happens. all i see is the altitude staying and 0 fpm on the vertical speed. Why is the efis telling the AP to correct yet it appears the AP isn't making a response.
Alan