iFly 737 MAX Autobrake Disarm with FSUIPC

[DannyEvans]

Hi There, 

I'm having an issue with the 737 Max disarming autobrakes on touchdown whenever the toe-brakes are calibrated via FSUIPC. I've isolated this issue to just the IFly's Max, no other aircraft (payware or default) are affected. I'll provide my system/hardware details below and a test scenario:

 

System/Hardware

- i7-9700, RTX3060, 32GB Ram, 1 TB SSD, Fully updated windows/drivers

- Thrustmaster Airbus Joystick (brake axis deleted)

- Cyborg V.1 Joystick (brake axis deleted)

- Logitech Flight Rudder Pedals (Where toe brakes are calibrated)

- FSUIPC6, Version 6.2.2 (Registered)

- Prepar3D V5.4.9.28482

- Windows 11 Version 24H2 

- iFly 737 Max (Latest version)

 

Prior to Touchdown:

- Stabilized ILS Approach

- Speedbrakes Armed

- Flaps 30

- Autobrake 3

 

On Touchdown:

- Power Idle

- Speedbrakes Deploy

- Autobrake setting remains on 3, Disarm amber light ON, brakes do not apply

- Only ground friction and reverse thrust marginally slow down the aircraft

- Toe Brakes manually pressed via rudder pedals, actual braking commences

 

Notes:

I've tested regular braking of the plane while taxiing, parking, using the realistic parking brake mode, and for differential braking, it all seems to be working perfectly except for the autobrakes on touchdown. In the air on approach, there's no error or issues of any kind, and there is no indication the brakes are being applied erratically by hardware spikes/3rd party software. The issue happens right on touchdown.

 

Temporary Workaround:

The only solution (not really) that I've focused on has been when I isolated the issue to the FSUIPC brake calibration not working well with the iFly MAX. When I delete the brake calibration lines in the FSUIPC.ini file, the iFly's autobrake system works great on touchdown, however manual braking becomes very rough (i.e. Even with the brakes manually depressed say only 20%, a 100% brake force will apply, the action is not progressive as compared to when it's calibrated via FSUIPC). As a result, deleting the FSUIPC calibration does bring the autobrake functionality back, however it comes at the cost of having an incorrectly calibrated default manual braking axis.

 

Additional References:

 

Below is the Brake Section of my aircraft.cfg:

 

[brakes]

parking_brake = 1             

toe_brakes_scale=0.80         

auto_brakes = 4

hydraulic_system_scalar = 1   

 

Below is the Brake Calibration from my FSUIPC.ini file:

 

[JoystickCalibration]

LeftBrake=-16383,16383/8

RightBrake=-16383,16383/8

SlopeLeftBrake=15

SlopeRightBrake=15

 

Finding Summary

The core issue here seems to be that the FSUIPC brake calibration is somehow disarming the iFly Max's autobrake function on touchdown. 

 

It confuses me because this product does require the latest version of FSUIPC to function, however any calibration made via FSUIPC is wreaking havoc with the aircraft's autobrake system. I will attach my FSUIPC log file, my FSUIPC settings, and all relevant screenshots of the issue. Any help I can get on this would be greatly appreciated! 

 

Thank you in advance for your help 

 

 

****Update, I can only attach my INI file for FSUIPC, my log file from the latest file is too large to be attached or even pasted below. The logging was started at approx. 1000 AGL on approach to CYUL ILS RWY06L in the iFly 737 Max 8, and was stopped during the rollout on the runway after touching down. I used FS interrogate to identify any Brake-related codes in the log file. During the logging period, manual brakes were not used at all, nor was manual braking registered in the sim from what I could see. What's interesting though is that the log file read a bunch of lines coded as Read "32F9" which is the "Brake being used Flag", var U8, Size 1, Read Only, Category Controls. I'm absolutely confused over what is really causing this issue, and if it's an FSUIPC issue or an iFly issue (as no other aircraft is experiencing anything like this).

 

 

 

 

 

 

FSUIPC6 INI File.ini

[John Dowson]

Looking at your ini, the only thing you seem to be using FSUIPC for is the brake calibration, where you have set quite a big slope (flattened at the start and stepper later), and rudder calibration.
You don't have any assignments at all, neither axes or buttons. Are your brakes assigned in P3D, or in iFly itself?

I am not sure why brake calibration could affect the auto-brakes.

13 hours ago, DannyEvans said:

I can only attach my INI file for FSUIPC, my log file from the latest file is too large to be attached or even pasted below.

It is very large as you have so much logging enabled. Could you please just enable logging for the following (and disable the rest): Axis Controls, Events & Extras. Also, please add logging for offset 2F80 (as U8, and make sure to check to send to the normal log file). The file may still be too large to attach (your attachment limit will increase the more you post) - try compressing/zipping it.

This will show if the auto-brake setting in offset 0x2F80 is being changed. If it is, we may need to enable IPC Write logging to see if this is being changed by an external program, but leave this off for the first log.

It would also be useful if you could provide two log files - one with the FSUIPC calibration and the autobrake issue, and another with he calibration removed and the autobrake working as expected.

You could also try with the toe brakes both assigned and calibrated in FSUIPC, to see if this makes a difference. Try assigning the toe brakes using the Send direct to FSUIPC calibration option.

John

[DannyEvans]

Hi, 

Thanks so much for getting back to me.  My brakes are unassigned anywhere in P3D (except for "." for keyboard), but definitely not to any controller axis. I also assigned the toe brakes in FSUIPC as suggested above.

I recorded both logs as requested but even after compressing it to a .rar they're still too big to be attached. What I did instead was take any entries that have 2F80 in either log and just put those into one file (attached) and labeled it accordingly. Hybrid log File.rar

From what I can tell, when the brakes calibration is active, 2F80 or any autobrake command isn't read, but without the calibration the log entries did read it and activate the autobrakes on touchdown. Really strange. Should I try it again with the IPC Write logging enabled?

Danny

 

[John Dowson]

26 minutes ago, DannyEvans said:

My brakes are unassigned anywhere in P3D (except for "." for keyboard), but definitely not to any controller axis.

Then where re your brakes assigned?

27 minutes ago, DannyEvans said:

I also assigned the toe brakes in FSUIPC as suggested above.

And then what ha[[ened?

27 minutes ago, DannyEvans said:

What I did instead was take any entries that have 2F80 in either log and just put those into one file (attached) and labeled it accordingly. Hybrid log File.rar

That doesn't help much - I need to see the full logs. But it does seem that something is turning off the autobrakes
You can also use a free file transfer service to show me the logs, e.g. https://filetransfer.io/

 

31 minutes ago, DannyEvans said:

From what I can tell, when the brakes calibration is active, 2F80 or any autobrake command isn't read, but without the calibration the log entries did read it and activate the autobrakes on touchdown

2f80 just shows the autobrake setting as it is in the sim - nothing to do with reads.   It is showing 1 (off) when calibrated, but going from RTO to off and back to RTO when calibrated, But hard to tell anything more when that is all that is logged. But looks lik it was never even set to RTO when calibrated, if the offset always holds 1. But, I really need to see the full logs to understand anything here.

But it is certainly not FSUIPC altering auto-brake settings. May be the calibration is triggering iFly to turn this off, not sure. Where are your brakes assigned? And what happens if you remove the current assignment and assign in FSUIPC?

[DannyEvans]

I ran the tests again to get new log files, this time from brakes off on takeoff to a full stop landing (short flight starting and ending at CYYZ). 

Currently the Left/Right Brakes are only assigned via FSUIPC to my knowledge, as suggested. In both tests, the results were the same when trying with & without the brakes calibrated.

I used your link and I attached both the logs, along with my user controls file for P3D and my current FSUIPC.ini (without the brakes calibration). 

https://limewire.com/d/Elgms#WwQbqWkls4 

I hope that's a little bit more useful! If there's anything else you would like me to try and log please let me know.