missing info Engine Degraded

[Cool-Hand]

Hi, I'm sure there is some kind of operator error on my part and in the past the P-47's engine was pretty reliable with WEP usage, recently I have been experiencing a brief drop in the engine and a rolling moment followed by an uncontrollable rise in oil pressure with the message in the debrief "Engine Degraded". It happens randomly sometimes during WEP usage other times afterwards when I return to a lower power setting for cruise. Sometimes, I can really abuse then engine and will will tick on just fine for several Rearms and Refuelings on multiplayer until I run out of Water injection...other times it dies if I just tap the water for minute.

 

I'll attach a track that I tried to stay well below 65" for the fight and around 2 to 3 minutes on the 3rd 109, I get the "engine degraded" failure. Pardon the shooting but its the third time I ran it and got similar results. I'm sure it's probably operator error on my part and maybe someone more knowledgeable can set me straight but nearly all my losses since November this year have been due to this and I'd like to know what I might be doing wrong or if it's possibly a bug. I don't have random failures enabled and it happens online and offline for me as well.

I have repeated with oil cooler full open and slightly open from neutral and got similar results but random times it fails.

engine dead3.trk

Edited December 11, 2021 by Cool-Hand
added screnshot of debrief

[razo+r]

Just to make sure, you warmed up the engine before flying, correct?

[Cool-Hand]

Yeah, I've got quite few hours in this bird and noticed this behavior starting a month or so back for me and if you watch the track it's an air start.

Edited December 11, 2021 by Cool-Hand

[grafspee]

Have you cut the throttle during fight, and have you opened oil cooler fully ?

64" for WEP is max not 65", but this is not important, you can push more then 70" but you need to watch your carb temp, in hot day you won't be able to push above 60" so staying below 64 won't guarantee engine safe operation, second thing watch boost in high speed dives it can rise up quite a bit. 

Edited December 12, 2021 by grafspee

[Cool-Hand]

Nope I'm well aware of cutting the throttle and incurring bearing damage which is very distinct. All those questions you ask are answered in the roughly three minute track I posted. Yeah you are right 64" is max, fat fingered the post i guess. I get this failure when the oil cooler is open or neutral, it doesn't seem to matter which is what is perplexing to me. I kind of suspect the oil temp gauge may be lagging or reading incorrectly but i don't have the under the hood sim knowledge or diagnostic damage model tools like nineline or yoyo would to make a call like that.

 

If it was as simple as RTFM that would be one thing but i get the same message and failure at different times, sometimes during WEP usage for a minute, sometimes well after and I am cruising away and at cruise power setting with the temps in the green. What is doubly perplexing is i can run the engine full WEP for 15 mins and have no problems at all sometimes, the only limiting factor is they dont refill the water injection at re arm and refuel. 

[Tuturuu]

Hey what is the context of the mission ? 

Quick action dogfight ?

 

I noticed on storm of War that repairing the P47 does not seems to reset the random WEP/slight overheat failure Factor 

[grafspee]

3 hours ago, Cool-Hand said:

Nope I'm well aware of cutting the throttle and incurring bearing damage which is very distinct. All those questions you ask are answered in the roughly three minute track I posted. Yeah you are right 64" is max, fat fingered the post i guess. I get this failure when the oil cooler is open or neutral, it doesn't seem to matter which is what is perplexing to me. I kind of suspect the oil temp gauge may be lagging or reading incorrectly but i don't have the under the hood sim knowledge or diagnostic damage model tools like nineline or yoyo would to make a call like that.

 

If it was as simple as RTFM that would be one thing but i get the same message and failure at different times, sometimes during WEP usage for a minute, sometimes well after and I am cruising away and at cruise power setting with the temps in the green. What is doubly perplexing is i can run the engine full WEP for 15 mins and have no problems at all sometimes, the only limiting factor is they dont refill the water injection at re arm and refuel. 

Your track is broken for me, it ends like in 20s, you just dive in to the sea and that's it

Edited December 13, 2021 by grafspee

[Tuturuu]

Tracks will do almost something different everytime you replay it unfortunately but you can read every inputs and variables with it i think (at least devd Can)

[Cool-Hand]

5 hours ago, Tuturuu said:

Hey what is the context of the mission ? 

Quick action dogfight ?

 

I noticed on storm of War that repairing the P47 does not seems to reset the random WEP/slight overheat failure Factor 

 

Yeah just a quick airtart dogfight against 4 k4s. Yeah its funny on storm of war ive had the same plane for 5 or 6 sorties and not had any issue with WEP usage all the way to drying up the water tank and others where even a minute of usage will result in the engine dipping suddenly audibly and a slow uncontrollable rise in oil temp and loss of power. It seems to happen if I baby or abuse the engine, doesnt seem to matter.

[kablamoman]

I've taken the jug out a few times on SoW and it's the one engine I can't get to behave reliably (and I fly the Dora pretty regularly, so that's saying something).

I've often experienced the same failure mode (loss of power, engine oil temp rising) after an hour or so of flying, often with a reduction of power -- it's especially frustrating when you successfully RTB after a long sortie only to have it roll back on you in the pattern. I've checked and double checked and as far as I can tell I'm not exceeding any limits, and as a rule any changes to prop, throttle or boost controls are done very gingerly.

Open to any suggestions as I'd like to fly it more, but it's just way too fragile to use online as far as I can tell.

[Brigg]

probably a stupid question but did you have your generator switched on? 

because when the battery gets low it doesnt give correct needle readings on the gauges. Where you thought you were ok temps wise you actually could of been a lot higher

[Cool-Hand]

17 hours ago, Brigg said:

probably a stupid question but did you have your generator switched on? 

because when the battery gets low it doesnt give correct needle readings on the gauges. Where you thought you were ok temps wise you actually could of been a lot higher

Yep generator comes right on after start. This problem seems to manifest air start or ground start, doesnt seem to matter.

[Lixma 06]

I've been having the same issue and I'm reluctant to use the 47 online because I don't trust it.

Here's one example.

I take off at 7:16 with both oil and intercooler open. Cruise down the coast for a bit, turn around, and at 7:22 apply military power (no water). At 7:24:20, just two and a half minutes later (all temperatures fine) I move the oil and intercooler shutters back to neutral and immediately the engine dies. I don't know whether that indicates causation or just unfortunate timing.
 

 

p-47 engine.trk

[saburo_cz]

I do not know if it is the reason, but 56inHg without water injection is definitively not correct engine setting.

52inHg is maximal permissible without water injection for fuel what we have in DCS W.

[Reflected]

@Lixma 06 your oil temperature ran away.

[Lixma 06]

4 minutes ago, Reflected said:

@Lixma 06 your oil temperature ran away.

These are my gauges the moment before I move the oil and intercooler shutters back to 'neutral' - all of them in the green blue. One second later my engine blows.

Timestamp here...

3 hours ago, saburo_cz said:

I do not know if it is the reason, but 56inHg without water injection is definitively not correct engine setting.

52inHg is maximal permissible without water injection for fuel what we have in DCS W.

 

I'd be surprised if the difference between running safely at military power and destroying the engine was a mere 4", but I don't know.

[Reflected]

Yeah, I'm not saying it's correct or realistic - it may be though- , but in game, you want the oil cooler wide open unless you're at cruise settings.

[peachmonkey]

you're running the engine at 2700 rpm's (past green) and manifold in past green/red mark. In my experience the engine won't last more than 2-3 minutes with these settings without water. Lower the rpm's to the green (2600) and then you can run at higher manifold for 5-10 minutes, or vice versa...

Edited January 14, 2022 by peachmonkey
added water

[grafspee]

You can run engine at 2700 up to 52inch for very long time, just watch oil temp from my experience cooler needs to be wide open, after take off it give impression that neutral position is ok bu it will creep above 100c if you do nothing.

Anyway engine is too fragile still, if you over rev the engine it dies even if max diving rpm are not exceeded so as i feel it engine in P-47 wasn't tweaked for very long time.

Edited January 14, 2022 by grafspee

[peachmonkey]

2 hours ago, grafspee said:

2700 up to 52inch

up to 52inch is the key here... the video shows 56" at 2700

[Lixma 06]

I think I've found the reason I was inadvertently running too high manifold pressure.

When you're on the deck (50m-ish) you can push your physical throttle to maximum and the MAP will sit squarely on 51" without having to finesse it. No fuss - perfect!

But climb to just 100m and the MAP surges to 57" (accompanied by nasty mechanical sounds). Descend back to 50m and the MAP will remain on 57" until you back off the throttle whereby the MAP decreases to healthy levels and you can again go max throttle to 51". Weird.

 

surge.trk

Edited January 15, 2022 by Lixma 06

[grafspee]

9 hours ago, Lixma 06 said:

I think I've found the reason I was inadvertently running too high manifold pressure.

When you're on the deck (50m-ish) you can push your physical throttle to maximum and the MAP will sit squarely on 51" without having to finesse it. No fuss - perfect!

But climb to just 100m and the MAP surges to 57" (accompanied by nasty mechanical sounds). Descend back to 50m and the MAP will remain on 57" until you back off the throttle whereby the MAP decreases to healthy levels and you can again go max throttle to 51". Weird.

 

surge.trk 2.01 MB · 0 downloads

 

Look at turbo rpm, when you climb up it spools up so this boost comes from turbo, once turbo kick in it can maintain boost at lower alt.

[Lixma 06]

Why is it happening, though? What's different between 0m and 100m that causes the MAP to increase? I wonder if it's a 'hack' to allow players to take off at full throttle without having to worry about wrecking the engine?

[grafspee]

Hard to tell, but P-47 manual tells pilot to not draw more then 52" on take off, but apparently in DCS you can't do tat 52 is about max you can have for take off, manual mention something about take off stop on throttle quadrant.

[saburo_cz]

12 hours ago, Lixma 06 said:

Why is it happening, though? What's different between 0m and 100m that causes the MAP to increase? I wonder if it's a 'hack' to allow players to take off at full throttle without having to worry about wrecking the engine?

Unwanted MAP increasing is caused by sudden the turbo's RPM jump from 2000 to 4000.

It happens sometime in some conditions.

You can usually set the turbo's RPM in this range too (somewhere between 2000 and 4000), but in this case not...

It is probably one from several trouble what the P-47 supercharger has in DCS W.

 

A trigger switches opening waste gate, perhaps due to increasing altitude, but missing steady increase in the turbo's RPM causes your MAP jumps up.

Edited January 16, 2022 by saburo_cz