Throttle surge - SOLVED

Post any technical issues here. This forum gets priority from our staff.
User avatar
RMM
Airman First Class
Posts: 74
Joined: 24 Nov 2015, 17:49

Throttle surge - SOLVED

Post by RMM »

P3D v 3
Suddenly this problem shows up for the first time out of nowhere. Starting up with engine running at idle. Suddenly the engine goes to full throttle with zero input. Dropping to zero throttle or advancing the throttle, either way restores control. If I hold at idle, after some time another throttle surge will occur.

This is something that I read about going back in time, but nobody presents the fix.
What is the cause? What is the cure?

EDIT:
On full throttle climb out had a random reduction in throttle. On base, had a random surge.

thanks
RMM
Last edited by RMM on 17 Nov 2017, 19:30, edited 3 times in total.

User avatar
Nick - A2A
A2A Captain
Posts: 13728
Joined: 06 Jun 2014, 13:06
Location: UK

Re: Throttle surge

Post by Nick - A2A »

Sounds like a control conflict RMM - in other words, some axis, button or key is sending throttle commands as well as your main throttle. Another possibility would be a faulty/dirty potentiometer in your throttle, or just a bad calibration

If you can give us a bit more info on your throttle hardware and software (e.g. do you use FSUIPC?) we can hopefully help. Also, can you confirm you've applied a recent Accu-Sim update to the 172 since installing?

Thanks,
Nick

User avatar
RMM
Airman First Class
Posts: 74
Joined: 24 Nov 2015, 17:49

Re: Throttle surge

Post by RMM »

Hello Nick..
Thanks for the assist. There were no hardware changes that would explain this suddenly starting.
I fly with an IrisDynamics Yoke via profiles in FS-Force2. P3Dv3.4 Saitek throttle quadrant. Saitek Cessna Trim Wheel.
I do not use FSUIPC.

I have reviewed assignments very carefully to assure no conflicts. Evidenced by several hours of flight time without this new problem of sudden Throttle Surge.

I will check for calibration on the throttle and report back.

Strange to say, but I changed airports from PGUM to KHII and the problem did not follow me there. Will fly some tomorrow and advise.

thanks
RMM

User avatar
Nick - A2A
A2A Captain
Posts: 13728
Joined: 06 Jun 2014, 13:06
Location: UK

Re: Throttle surge

Post by Nick - A2A »

Thanks for the added info RMM. Sounds like an odd one so please let us know if the problem persists, and if so, if it's just in the A2A Skyhawk.

Also, just to reiterate, please make sure your Accu-Sim installation is fully up to date too: http://a2asimulations.com/forum/viewtop ... 23&t=57819.

Cheers,
Nick

User avatar
RMM
Airman First Class
Posts: 74
Joined: 24 Nov 2015, 17:49

Re: Throttle surge

Post by RMM »

Today the throttle surge problem became worse. Both directions, power up and power down surges.
Almost incessant. Makes flying impossible.

Yes, I have applied the most recent update package.
Yes, the same problem with the LM J3 Cub. I can see the throttle at my left side actually move on its own.

I don't fly other aircraft. The C172 is for real world training support. Other aircraft have no value for me.

Please advise.
Thanks
RMM
Last edited by RMM on 14 Nov 2017, 08:56, edited 1 time in total.

User avatar
Oracle427
Chief Master Sergeant
Posts: 3916
Joined: 02 Sep 2013, 19:30
Location: 3N6
Contact:

Re: Throttle surge

Post by Oracle427 »

Have you checked your control calibrations? Do you have a noisy signal from your hardware? You will see the position indicator bouncing about rapidly in the calibration screen of the signal has a lot of noise.

As you move the control through its range of travel check to see if the signal spikes Also check to see if moving one control affects the signals of the others.

This could be a hardware issue.
Flight Simmer since 1983. PP ASEL IR Tailwheel
N28021 1979 Super Viking 17-30A

User avatar
RMM
Airman First Class
Posts: 74
Joined: 24 Nov 2015, 17:49

Re: Throttle surge

Post by RMM »

I made some more edits to note this is also a problem in the J3 Cub from LM.

I just did the calibration and found no difference. The calibration in P3D looked normal. No anomalies were apparent as I moved the three axes of the throttle quadrant.

I do have access to another throttle quadrant. Do you suggest I swap them? I agree this could be a hardware problem.

Thanks

RMM

User avatar
Nick - A2A
A2A Captain
Posts: 13728
Joined: 06 Jun 2014, 13:06
Location: UK

Re: Throttle surge

Post by Nick - A2A »

RMM,

Yes, it's definitely a good idea to eliminate the throttle hardware itself. I'd suggest you try a flight or two with it unplugged and control the throttle/mixture with just the mouse and see if the problem reoccurs.

Also, make sure your default start-up flight doesn't use the A2A 172 as this can cause problems. It's recommended to load a default P3D aircraft before switching to the Skyhawk.

Thanks,
Nick

User avatar
RMM
Airman First Class
Posts: 74
Joined: 24 Nov 2015, 17:49

Re: Throttle surge

Post by RMM »

Disconnected the Saitek Throttle Quadrant. Started up with the default P3D aircraft, some military jet. Switched to the A2A C172 and also to the LM J3 Cub
BOTH aircraft, without the throttle connected, still had this constantrepeating throttle surge.

I also noticed that the throttle did not respond properly to either the mouse wheel or the number pad assignments from the "Mouse Yoke" settings.
Rolling the mouse wheel would cause the throttle to move a little but not through the needed range from idle to full power.

In calibrating the Throttle Quadrant, after watching a few videos, I can detect a tiny bit of quivering in a few spots along the 0 to 255 scale. But this was very limited.

Thoughts?

RMM

User avatar
Nick - A2A
A2A Captain
Posts: 13728
Joined: 06 Jun 2014, 13:06
Location: UK

Re: Throttle surge

Post by Nick - A2A »

When you're experiencing the throttle surge RMM, I suggest you unplug all your hardware, one item at a time until the behaviour stops. This way you should be able to see exactly what is causing the issue.

If it still persists when everything is disconnected, it will indicate a non-hardware issue of some sort, but my money would still be on a conflict somewhere.

Thanks,
Nick

User avatar
Lewis - A2A
A2A Lieutenant Colonel
Posts: 33284
Joined: 06 Nov 2004, 23:22
Location: Norfolk UK
Contact:

Re: Throttle surge

Post by Lewis - A2A »

Hello,

yes you will want to unplug all devices to aid in troubleshooting, I agree with Nick, it sounds like you have some stray mapping or software causing control inputs.

thanks,
Lewis
A2A Facebook for news live to your social media newsfeed
A2A Youtube because a video can say a thousand screenshots,..
A2A Simulations Twitter for news live to your social media newsfeed
A2A Simulations Community Discord for voice/text chat

User avatar
RMM
Airman First Class
Posts: 74
Joined: 24 Nov 2015, 17:49

Re: Throttle surge

Post by RMM »

The cause lies in the IrisDynamics Yoke. It was easy to eliminate the Saitek Throttle Quadrant and Cessna Trim Wheel.
So I went through all the settings and removed all bindings that overlapped. There were a few of those.
The problem persists. I have contacted IrisDynamics for guidance.

If you have any suggestions, please let me know. I will advise what happens next.

RMM

User avatar
Nick - A2A
A2A Captain
Posts: 13728
Joined: 06 Jun 2014, 13:06
Location: UK

Re: Throttle surge

Post by Nick - A2A »

Okay, thanks for the update. What sort of handle do you have on the yoke? Does it have hat switches or buttons? If so, I'm wondering if one of these could be assigned to a throttle input.

Nick

User avatar
RMM
Airman First Class
Posts: 74
Joined: 24 Nov 2015, 17:49

Re: Throttle surge

Post by RMM »

Hello Nick..
There is scope for a throttle assignment from the IrisDynamics Yoke. In fact, on close review yesterday, I found a throttle assignment to a "slider" and deleted the assignment. I was excited and thought.."OK. Found the culprit!" But unfortunately, on restart the erratic throttle returned. I have contacted IrisDynamics for their suggestion.

Now there are no overlapping/duplicate assignments anywhere. One assignment for a given function and only from one device. A bit later tonight, I will start up my flight sim computer and recheck everything again. I am going to unplug the usb keyboard as well this time. Maybe there is an odd combination of usb devices that triggers this behaviour.

I agree we have a hardware problem. Should be close to the solution now.
If you have any other flash of insight, please do advise.

Much appreciated. Thanks to you and Lewis, also. Will come to you with an update as soon as I hear from IrisDynamics.

RMM

User avatar
Nick - A2A
A2A Captain
Posts: 13728
Joined: 06 Jun 2014, 13:06
Location: UK

Re: Throttle surge

Post by Nick - A2A »

Yes, sounds like we're getting somewhere. Do you just use the control assignments within P3Dv3, or is there additional software involved such as FSUIPC4 or an Iris Dynamics control interface of some sort?

Thanks,
Nick

new reply

Return to “C172 Trainer Tech Support”

Who is online

Users browsing this forum: No registered users and 17 guests