Can someone possibly give me a TL;DR on engine management?

[Tree_Beard]

I take off and close cowl flaps, interlink boost and throttle, and then fly similarly to how I fly the BF109, which is keeping throttle around "mil power" (like 80% or so), until I really need a boost of speed, where I go max power for short stretches. I never unlink boost and throttle. 

My issue is that the engine eventually stalls out on me like almost every flight, so clearly I'm not doing something right.

There is a lot of scattered, conflicting info out there, so I am hoping someone can give me a short how-to on what I need to be doing instead of what I am currently doing.

Thanks. 

[razo+r]

To power up: Increase RPM, Increase throttle, and if throttle is full open and desired MP cannot be reached, increase boost lever. 

To decrease power: decrease boost lever, if boost lever fully aft and MP still above desired value, decrease throttle, then decrease RPM.

Important to watch: Oil temp is probably the most important one, but also check carb temp and cylinder head temp. Open/close respective coolers as required. 

Don't let the engine windmil for too long. 

Obey the engine limit tables. 

And very important: warm up your engine properly after engine start. 

Also, depending on your loadout and fuel load, don't forget to switch fuel tanks. 

If you follow all this, your engine should stay alive. 

Edited July 3, 2023 by razo+r

[Tree_Beard]

On 7/3/2023 at 2:28 PM, razo+r said:

To power up: Increase RPM, Increase throttle, and if throttle is full open and desired MP cannot be reached, increase boost lever. 

To decrease power: decrease boost lever, if boost lever fully aft and MP still above desired value, decrease throttle, then decrease RPM.

 

So it sounds like you're running the boost lever disconnected from the throttle always?

Edited July 5, 2023 by Tree_Beard

[grafspee]

4 minutes ago, Tree_Beard said:

So it sounds like you're running the boost lever disconnected from the throttle always?

 

You can use throttle interconnected with boost or not up to you, with boost lever and throttle interconnected you lose some power in peak it may be 300 hp less.

But main difference between B-109 and P-47 is that you control engine rpm separately when in Bf-109 engine rpm are linked with throttle.

You can link rpm lever in P-47 to throttle but i am not sure if you can use that all the time.

So watch your rpm and do not over boost engine this is often quick death if you set very high MP while at low rpm.

[razo+r]

1 hour ago, Tree_Beard said:

So it sounds like you're running the boost lever disconnected from the throttle always?

 

Like grafspee said, you can have them connected, but you will lose power this way. I personally always run it disconnected.

 

[Andy1966]

 Hi, sounds to me like you are over boosting the engine (too high manifold pressure not enough RPMs) not sure though, a track would help. 

[peachmonkey]

On 7/3/2023 at 5:10 PM, Tree_Beard said:

I take off and close cowl flaps, interlink boost and throttle, and then fly similarly to how I fly the BF109, which is keeping throttle around "mil power" (like 80% or so), until I really need a boost of speed, where I go max power for short stretches. I never unlink boost and throttle. 

My issue is that the engine eventually stalls out on me like almost every flight, so clearly I'm not doing something right.

There is a lot of scattered, conflicting info out there, so I am hoping someone can give me a short how-to on what I need to be doing instead of what I am currently doing.

Thanks. 

if you're coming from IL2 (since you mentioned %) then there are no engine timers in DCS, there's a full thermodynamic simulation of cooling and mechanical systems in each engine.

With P47:

- don't go above 52" of manifold pressure. You can occasionally overboost for 5-10 seconds, but make sure you bring that MP down to below 52". It doesn't matter whether you're using Throttle only, or Throttle+Turbo linked.

- if you need more power and must go above 52" you need to turn the water injection on. At which point the engine can boost up to 64" MP for 10-15 minutes. 64"is the max on water, if you go above it the engine will start to degrade very quickly (30-50 seconds) due to rising temperature and other factors.

- the Max MP in either of above cases is best achieved with the RPM set to 2550/2600 (continuous max) or 2700 (military max 15mins).  Anything above 2700 will kill the engine within 30-60 seconds.

- there are additional detrimental cases such as pushing 52 or 64" MP with much lower RPM (2000-2400) at which point the engine starts to experience detonation and will die within 1-10 minutes.

- make sure the Oil temperature is always in the green, using the oil cooler shutters. If they are fully open and the oil temp is climbing into red zone then lower MP and RPM's, or the engine will die in 1-5 minutes.

- forget about all % settings/read outs, they don't really serve as good indicators of the engine's health. Watch the gauges and remember the above mentioned limits, that's where it's at.

 

It's not an easy bird to dogfight with due to all the lever action / gauge watching

 

[grafspee]

@peachmonkey all of that what you said is crucial to operate P-47 i will only add that for ppl who start adventure with DCS P-47, it is very good to set oil cooler shutter wide open all the time, it won't impact performance much but it will save engine from death very often  

[Art-J]

^ I concur. Months ago tried "torture testing" with continuous hefty overboost at sea level (water injected 75" after a dive, down to 71" level flight @ 2550 rpm). As long as oil shutters were wide open keeping the temp below redline, the engine was surprisingly resilient and kept on ticking no problem. Got bored after 25 minutes or so and stopped the test, but I suppose nothing bad would happen as long as the water supply was still available.

At the same time partially open intercooler doors were enough to keep carb temp within limits, which was good, because they are the ones that cause tons of drag when fully open.

Granted, one might want to repeat the test after recent engine modelling tweaks to see if these observations are still valid.

Edited July 6, 2023 by Art-J

[Obic]

Like it should be 

Max wide open throttle can be sustained as long as engine/oil parameters are kept under control. 
You just increase the chance that a weaker part might <profanity> the bed.
You can run boost in excess as long as it's not detonating. *Problem for you it's a game so your ass won't feel it* so restrain to operation manual.
Radial love speed as the airflow takes all the hot air away & cool the back cylinder better.

That being said coming back to the field in Real life, you would inform the crew chief that you exceeded the 15minute limit for the prescribe manifold */ Rpm.
Peaks of playing the game we get a factory new aircraft every time

[WingC3]

I'm new to the Jug, and I'm having intermittent engine issues with it.  (Unsurprising I'm sure).

I'm wondering, do you all tend to keep the same aircraft through many sorties: Landing, rearming and taking off again? Is the 15min of WEP cumulative such that after a couple flights you're basically obligated to get a new plane, or does resting the engine reset things over time as long as you didn't exceed the 15min in any single stretch?

Tonight I did 4 flights in the same Jug. Was very careful not to ever let the temperatures overheat.  Had two very successful dogfights.  After the 3rd kill, I reduced RPM and MP back to max continuous (MP was a bit lower at 40inHg).    Crusing along level for about 3 more minutes, and a grinding noise starts.  Then, power loss followed by complete seizure.

Temperatures were normal right up until the grinding noise, then they skyrocketed right as the engine died.

I'm at a complete loss as to what went wrong. I was very careful to not exceed 64inHg for more than a brief instant in any of the fights.

Do these engines just die after a few hours of flying??

Also, with the intercoooler shutters at neutral, I did notice that my carb temp was a bit low. Can that kill the engine on its own?

Edited December 9, 2023 by WingC3

[grafspee]

15 hours ago, WingC3 said:

I'm new to the Jug, and I'm having intermittent engine issues with it.  (Unsurprising I'm sure).

I'm wondering, do you all tend to keep the same aircraft through many sorties: Landing, rearming and taking off again? Is the 15min of WEP cumulative such that after a couple flights you're basically obligated to get a new plane, or does resting the engine reset things over time as long as you didn't exceed the 15min in any single stretch?

Tonight I did 4 flights in the same Jug. Was very careful not to ever let the temperatures overheat.  Had two very successful dogfights.  After the 3rd kill, I reduced RPM and MP back to max continuous (MP was a bit lower at 40inHg).    Crusing along level for about 3 more minutes, and a grinding noise starts.  Then, power loss followed by complete seizure.

Temperatures were normal right up until the grinding noise, then they skyrocketed right as the engine died.

I'm at a complete loss as to what went wrong. I was very careful to not exceed 64inHg for more than a brief instant in any of the fights.

Do these engines just die after a few hours of flying??

Also, with the intercoooler shutters at neutral, I did notice that my carb temp was a bit low. Can that kill the engine on its own?

 

This is big issue for all ww2 modules in DCS, they are modeled that way that pretty much engine will die after longer use like flying single airplane and going through couple tanks.

Engine models are way too sensitive, at first release P-47 main bearing modeling was nightmare, even now after couple fixes you can't go above 2800rpm because it kills engine instantly, despite fact that every P-47 manual states that engine can handle 3060rpm for brief time.

Famous P-51 WEP engine killer, i am so traumatized by this that i don't use WEP in P-51 anymore.

Low carb temp is good, only concern is too high carb temp.

Chances are that you are managing engine perfectly are high but it is just DCS which loves to kill engine w/o reason. 

Limits on WEP are only limits how long you can use it in single use not total flying hours.

If you are doing WEP for max allowable time you need to drop power to continuous and cool engine down.

My only advice is to keep oil cooler wide open in P-47.

Edited December 9, 2023 by grafspee

[WingC3]

Thanks. 

Like you say, it must have something cumulative from all the flights. It would be nice if you could shutdown and have maintenance done rather than having to get a new plane. Especially if you can't spawn a P-47 at the airfield where you've landed.

I took it up for another flight and tried to really put it through its paces. I used water injection at low level for 4 minutes, then rested it a bit. Climbed up, used it at high level. Did some dives... All good.  Tried to keep the MP and RPMs reasonably high until the plane was slowed down for landing.    Engine survived just fine. 

Thank goodness the piston engine in the PA28 I fly in real life isn't this tempermental. I'm sure students at the club abuse it all the time, and I sure as heck don't want it dying on me!

 

[grafspee]

3 hours ago, WingC3 said:

Thanks. 

Like you say, it must have something cumulative from all the flights. It would be nice if you could shutdown and have maintenance done rather than having to get a new plane. Especially if you can't spawn a P-47 at the airfield where you've landed.

I took it up for another flight and tried to really put it through its paces. I used water injection at low level for 4 minutes, then rested it a bit. Climbed up, used it at high level. Did some dives... All good.  Tried to keep the MP and RPMs reasonably high until the plane was slowed down for landing.    Engine survived just fine. 

Thank goodness the piston engine in the PA28 I fly in real life isn't this tempermental. I'm sure students at the club abuse it all the time, and I sure as heck don't want it dying on me!

 

Many engine abuses which effects should be noticed after 10 or more hours of engine life, DCS shows those effects sometime after couple minutes or even couple seconds.

I am not telling that engine should be immune to whatever how you treat it, but if you follow plane's manual, engine should last many many hours.

So for example over revving engine for 10s should not lead to immediate engine failure. Using WEP should not doom engine to death. 

Am i asking too much ?  If anyone putting this issue to question, asking too much ?

Edited December 9, 2023 by grafspee

[Cool-Hand]

To echo what's been said its a bit of a mystery how the engine will seemingly die from a little bit of Water Injection. I would love to know what "Engine Degraded" is caused by. That's the number one cause of engine failure I run into. It rarely seems to happen during a fight but usually happens 3/4ths of the way back to base after everything has calmed down and I'm at a low power cruise setting for fuel economy for 5 or 10 mins with all the gauges in the green. I get the sudden surge followed by the rapidly rising oil temp to a soon to be dead engine. Sometimes I can just go max throttle and 75in's running away and use all the water in the tank and have no problems though, it's just so random...the only link I've found though is the water injection. If I don't use it, I've never had the "Engine Degraded" failure.

@NineLine

Added a track to illustrate that it happens out of nowhere after combat just crusing around. Its a long track

Engine Degraded December 11 2023.trk

Edited December 12, 2023 by Cool-Hand
added track

[Gunfreak]

Maybe if the F4 wear and tear could be transfered to other aircraft (but it seems that would require remaking most of the internal parts) 

But that would be cool if abusing the e engine didn't automatically kills it in seconds. But caused wear and tear. 

But realistically a worn or damaged engine would get rebuildt or replaced.

But I have read a few instances of pilots both prop and jet having to fly aircraft that was know to be less then mint, meaning they flew them gently on missions.