Engine died for no apparent reasons

[Gunfreak]

Did an auto start. Took off at ata 1.2

Kept the engine within ata 1 and 1.1

After mabye 5 minutes in the air. The engine just died.

[Art-J]

Should've saved the replay track - otherwise how are we supposed to help with troubleshooting this issue?

[saburo_cz]

Auto start does not switch On "Guvernor Automation" - auto RPM control.

It is probably the reason for failure.

[grafspee]

Yep, over revving K-4 can easy kill engine. But someone had to not pay any attention to rpm gauge in flight to do so.

Edited March 11, 2023 by grafspee

[Jef Costello]

On 3/11/2023 at 10:48 AM, Gunfreak said:

Did an auto start. Took off at ata 1.2

Kept the engine within ata 1 and 1.1

After mabye 5 minutes in the air. The engine just died.

 I have the same problem in combat with 1.35ATA or less and the engine dies.

bF109k4 vs P47D engine die.trk

Edited March 20, 2023 by Jef Costello

[Art-J]

^ This time we've got a replay track and it's a bit puzzling indeed. Prop regulator clearly works and maintains RPM around 2200, boost never exceeds 1.25. The only thing that's worth investigating is oil cooler beahviour. Even at these modest power settings oil temp goes up during combat to 110 and stays there. Module manual is inconsistent in description if such temp is OK or not - in one place it says permissible max is 130, while in the other it says max is 95 but only "briefly" (?). So, which one is it - can we go above 95 or not? At the same time, oil cooler outlet flap remains almost closed.

The big MT patch allegedly brought some changes in oil pressure simulation, so one has to wonder it that hasn't caused some unintended (buggy) side effect? Last small patch hasn't changed anything further (probably, because we know patch notes are always incomplete).

Does anyone remember what oil temps the plane was reaching in typical combat scenarios two versions ago? In either case, some more test flying is needed.

[Jef Costello]

Thank you for your answer. My guess too there is "something" with the oil temp behaviour that cause engine to die. I did more tries at different altitude, til 20000ft, and the problem remains. Of course MW50 is unusable. Please ED investigate what's going on here.

Regards

[Jef Costello]

Here again 3 flights, in the 2 & 3 I removed the sounds mod from Echo19 for the Spit and the P51, switched off MW50 or selected P2 pump instead of 1&2, radiators in Auto or Open. Same result when I push to 1.39ATA. I joined the corresponding DCS log. Please forgive my aerobatic takeoffs

Cheers

Bf109k4 messing around engine quit1.trk Bf109k4 messing around engine quit2.trk Bf109k4 messing around engine quit3.trk dcs1.log dcs2.log dcs3.log

[Jef Costello]

Another one! One circuit and at the second takeoff engine quit at 1.1 ATA!

dcs4.log Bf109k4 messing around engine quit4.trk

Edited March 21, 2023 by Jef Costello

[zerO_crash]

Are you heating up the engine properly pre-flight?

[Jef Costello]

Just now, zerO_crash said:

Are you heating up the engine properly pre-flight?

As you can see the temps are ok before takeoff.

[zerO_crash]

Sadly, I cannot check the track-files atm. (bad performance after recent patches). I am not talking about the temperatures, I am asking specifically if you are doing the engine warm-up prescribed in the manual? Check the BF-109K4 manual on pages 123-124. If you haven´t done this, try it, follow the exact warm-up procedure, and check again.

[Jef Costello]

7 minutes ago, zerO_crash said:

Sadly, I cannot check the track-files atm. (bad performance after recent patches). I am not talking about the temperatures, I am asking specifically if you are doing the engine warm-up prescribed in the manual? Check the BF-109K4 manual on pages 123-124. If you haven´t done this, try it, follow the exact warm-up procedure, and check again.

I understand what you mean but it happens the same with quick start missions even those starting in flight. I noticed most of the time the engine quits at 1.39ATA. As I can see I'm not the only one who get this trouble:

 

Edited March 21, 2023 by Jef Costello

[zerO_crash]

4 minutes ago, Jef Costello said:

I understand what you mean but it happens the same with quick start missions even those starting in flight. I noticed most of the time the engine quits at 1.39ATA

 

There is too much to ask about, without being able to see the track-file. The one final section of the manual, that you can check before eventually opening a bug report, is to check pages 142 and further (engine overheating). It´s possible that you are pushing the engine too hard for too long at too low speed, or any of the other listed reasons there.

[Jef Costello]

I don't push engine too hard as can be seen in the tracks and even with 1.10ATA RPM in AUTO, oil temp rise at 110°C, the radiator flap is closed and engine quits at this power. 

[grafspee]

Oil gauges in german plane shows engine outlet oil temp and allied planes probes engine inlet oil temp , that is why german planes have limits at 130C and allied 90C-95C

110C oil temp in K-4 is completely fine.

[Art-J]

@Jef Costello Took a look at your last four tracks and found the culprit I think - you've always got fuel/MW selector set to "fuel" (down) position (see page 99 of the manual), which causes slow fuel system contamination with water and methanol - thus making the engine quit after a few minutes.

The selector by default shouldn't spawn in the wrong position in any mission (cold start / air start) unless you've got it assigned to some switch on your HOTAS, the switch sends the signal to the game all the time plus synchronize controls with HOTAS option is on. That's what most likely happens in your setup. I don't remember how this selector is called in controls, but that's what I'd check if I were you.

Edited March 22, 2023 by Art-J

[Jef Costello]

12 hours ago, Art-J said:

@Jef Costello Took a look at your last four tracks and found the culprit I think - you've always got fuel/MW selector set to "fuel" (down) position (see page 99 of the manual), which causes slow fuel system contamination with water and methanol - thus making the engine quit after a few minutes.

The selector by default shouldn't spawn in the wrong position in any mission (cold start / air start) unless you've got it assigned to some switch on your HOTAS, the switch sends the signal to the game all the time plus synchronize controls with HOTAS option is on. That's what most likely happens in your setup. I don't remember how this selector is called in controls, but that's what I'd check if I were you.

 

Thank you so much Art, I'm gonna check that, may be I've a control assign to the selector and at the start of the mission it synchronizes the position of this selector to fuel.

[Art-J]

The cockpit tooltip might be confusing, so to sum it up: if rear tank contains MW mix - the selector handle should be rotated UP, if it contains fuel, the handle should be rotated DOWN.

By default, the plane should spawn with handle UP.

Edited March 23, 2023 by Art-J

[peachmonkey]

thank you for the troubleshooting/explanation, @Art-J, I definitely learned something new

Just as a reference, this is where the MW50/Fuel selector is located:

null

[Jef Costello]

That was the culprit. Art-J you are my mate, thank you so much for taking the time to look at my tracks!

Best regards 

Jef