Engine fail

[BAT-2I]

Don't know If this has been mentioned already, but I've been away for a couple months with an injury and I just got back and I've been playing Storm of war for about a month now.  I seem to be breaking the P-51 engine a lot more than I used to.  I'm monitoring my temperatures The only thing that I don't seem to have any control over is my carburetor temp. Is that's what's causing my engine to seize, I'm already aware that if you adjust the throttle too fast you can break the motor and if you don't monitor your engine oil temperature or your coolant temperature it can also cause engine problems.  I'm pretty disciplined at the last three things that I've mentioned. again I don't seem to have any control over the carburetor I try to adjust the ram Air and it doesn't seem to work that well.  I understand they did a lot of updating since I've been gone, did I miss something?

[saburo_cz]

You can`t control carburetor temperature, it is ambient temperature.

 

HOT air control is for icing conditions and can`t be used above 12k feet. There is no icing conditions in DCS W.

What has effect is UNRAMMED FILTERED air, IRL used together with HOT air in icing conditions or alone in dust conditions, no dust conditions in DCS W.

But if you use filtered air, then only lose several hundrets feet critical altitude (if it still works, it did).

[grafspee]

Main thing which you have to monitor is relation between MP and RPM

Those 2 are the most important. So look at engine limitation chart and apply those rules.

RPM is limiting factor for available MP, for example at 2700 rpm max safe MP is 46" going a little bit above this 48" wont hurt the engine.

But flying at 61' and 2700rpm will kill engine. Same in case of super low rpm like 2000rpm and 40"

So for now the safest way is to just stick to this chart.

As far as i know, only thing which was changed recently is ground handling.

Any engine or FM related things weren't changed since i fly p-51 in DCS which is couple of years.

If it comes to operation of carburetor air control there is no easiest way just to show this.

If you switch to filter air position you loose dynamic pressure. MP increase from RAM air depends on IAS, higher IAS gives higher MP gain. So at low speeds like climb speed 160-170IAS there is little gain from RAM air, but at speeds above gain become much higher.

Edited April 5, 2021 by grafspee

[Sacarino111]

Hi. I don t know if I do it right, but I usually open or close the Coolant or the oil radiator manually to help me control the temperatures of the engine. Those controls are on the left hand side panel, two levers with a cover (for auto funtion) over them. I have them bound to the MFD butons so I can reach them with ease and they seem to have great impact on those temperatures. As I said, maybe I use them wrong, but they do the trick for me. By the way, closing the lever cover is suposed to put them into auto opening/closing, but they fail considerably on keeping the right temps. Also, keeping them open or too much time in the open position lowers the temperatures way too much, so keep an eye on those temps (besides the aerodinamic impact, of course).

Saludos.

Saca111

[grafspee]

While in combat, manual control is out of question, l live it at auto, i open coolant door before take off in higher ambient temps, beside that i leave them on AUTO.

My engine never failed because  auto holds wrong temps. 

In my case engine fails after using WEP, if i don't use it im fine.

[BAT-2I]

10 hours ago, grafspee said:

While in combat, manual control is out of question, l live it at auto, i open coolant door before take off in higher ambient temps, beside that i leave them on AUTO.

My engine never failed because  auto holds wrong temps. 

In my case engine fails after using WEP, if i don't use it im fine.

So just to get this straight, u open the coolant all the way for take of then place it back to manuel?, Also while left at auto and the gauges read high I am still good cause the gauges are wrong?, For example 46 no and 2700 rpm is continuous, but when running that I go over my temperature limits pretty fast.  

[122sqn Bruv]

Some of us have different views on what "combat" is.  How are you flying the P51?

 

I find if rads are left in auto whilst low and slow things heat up pretty quick so I have to manually open everything.   Once your done flying like a Spitfire I then pop them back to Auto.

 

Don't forget the fuel booster switch is up. 

[grafspee]

2 hours ago, No.119_Bruv VK-B said:

Some of us have different views on what "combat" is.  How are you flying the P51?

 

 

I was thinking about manual maintaning optimal temps. Which impossible in combat. I do pop doors wide open in combat. When i gain speed i pop it back to auto.

3 hours ago, BAT-2I said:

So just to get this straight, u open the coolant all the way for take of then place it back to manuel?, Also while left at auto and the gauges read high I am still good cause the gauges are wrong?, For example 46 no and 2700 rpm is continuous, but when running that I go over my temperature limits pretty fast.  

After take off i switch to auto. I pop red coolant cover up

[grafspee]

Regardless what was said. OP mentoned already that he kept temps in green. So no need to talk about this. Only left is miss managing rpm and MP.

I assume that OP know that fuel tanks in p51 arent interconnected so pilot have to switch to other one when first drains out

 

[122sqn Bruv]

You said

 

"While in combat, manual control is out of question, l live it at auto, i open coolant door before take off in higher ambient temps, beside that i leave them on AUTO."

 

then in next post

 

"was thinking about manual maintaning optimal temps. Which impossible in combat. I do pop doors wide open in combat. When i gain speed i pop it back to auto."

 

This is why I asked him how he is flying when the engine fails.   I've never had a P51 engine fail randomly unless I've used WEP for too long.   Even then it can be pretty random.   2700rpm 46mp for going places and 3000rpm 61MP when fighting.  radiators and coolant wide open.   It's not much fun hanging on your prop in a P51 when your used to flying a Spitfire but it can be done when fuel is light with some success.   Just not advisable.   Flying the P51 the way it was designed for, AUTO is fine as we have both stated. 

 

If he kept them in the green then the choices are fuel booster not selected up / fuel or mismanged RPM settings. 

[Nealius]

I've had the Mustang's engine randomly fail once on a standard takeoff (3000/52)--not catastrophic but a failure nonetheless--in conditions where it shouldn't have, so there could be something up. We won't know without a track file to watch, and I thought there were some known issues with the cooling system modeling as well. 

[grafspee]

20 minutes ago, Nealius said:

I've had the Mustang's engine randomly fail once on a standard takeoff (3000/52)--not catastrophic but a failure nonetheless--in conditions where it shouldn't have, so there could be something up. We won't know without a track file to watch, and I thought there were some known issues with the cooling system modeling as well. 

Then you have to do something wrong, i did not encounter any troubles when keeping engine below 61".

I do my take offs at 61" very often.

[Nealius]

7 minutes ago, grafspee said:

Then you have to do something wrong, i did not encounter any troubles when keeping engine below 61".

I do my take offs at 61" very often.

 

Does closing the radiator/oil cooler doors to accelerate warm-up on a 20C day, then putting them to auto once temps are in the green before takeoff count as "doing something wrong?" That was the only thing I did different from usual. Temps were green all throughout takeoff and gear up, then as I reduced MP from 52 to 46 the oil temp simultaneously rose past the red line with the same pace as my throttle reduction, and I lost most of my engine power. 

[grafspee]

1 hour ago, Nealius said:

 

Does closing the radiator/oil cooler doors to accelerate warm-up on a 20C day, then putting them to auto once temps are in the green before takeoff count as "doing something wrong?" That was the only thing I did different from usual. Temps were green all throughout takeoff and gear up, then as I reduced MP from 52 to 46 the oil temp simultaneously rose past the red line with the same pace as my throttle reduction, and I lost most of my engine power. 

I use Auto position for warm up, it will close doors when engine cold, and it will open then when hit critical temps, manually keeping them closed, a bit dangerous for me, too easy to over heat then.

About P-51 cooling system topic.

I think that it is something not right there.

One thing is that Auto position keeps too high temps, when manual describe AUTO position should hold green range unless cooling doors are wide open then temps can go higher, case in DCS looks different. AUTO holds temps a bit higher then green range. Which is not critically bad since it guards max temps pretty good.

Second thing the most important for me that radiator efficiency seems to be under performing. Set 25C ambient temp and take off in p-51 with shutters set to AUTO coolant temp will over shoot 121C limit, take same P-51 but load it with bombs and rockets you will hit close to 150 at full power take off.

There is not a single mention about that issue in any manual. 

The most weird thing is that after take off when im accelerating through 170mph coolant temp still rising up, hee? 170mph + prop wash isn't enough to cool it off ?

P-51 has single coolant radiator but this one is big.

In DCS when outside temps are +15C i open coolant door before every take off alwayes.

 

Edited April 9, 2021 by grafspee

[Nealius]

This is an interesting discrepancy. The only temp I have ever seen go above green (and on a regular basis) is oil temp. My coolant temps are always in the green or below green. 

[grafspee]

5 hours ago, Nealius said:

This is an interesting discrepancy. The only temp I have ever seen go above green (and on a regular basis) is oil temp. My coolant temps are always in the green or below green. 

So are you using air start, you've never tried to take off P-51 in hot day in DCS ??

Look at this, max take off weight 61" 3000rpm, even when i reduce to 50" wont help much in temps which can be tricky for short normandy fields. 25C ambient temp.

Watch coolant temp.

 

250mph temp dive below redline, just imagine combat at high alt where your IAS is 200-250, so what i need to drop power? 24k ft 61" and your temp shoots out above limit.

P-51 D final iteration of this fighter, and coolant door actuators are way to slow, they cant keep up with temps change.

As you can see 121C starting form 80C happened in a blink of an eye in mean time coolant doors barely start moving at this point.

About Oil temp as you can see it stays very nicely at 85C for that power it is more then satisfactory. 

now we have 25C just imagine what would happen at 30 or more  P-51 cant operate at temps above 25C

No manual for P-51 mention anything about temps problems at take off.

Edited April 10, 2021 by grafspee

[Nealius]

I fly everything from the ramp. Didn't think that would make a difference. We might also have to define what a "hot" day is, because 25C isn't hot. 28+ I'd consider hot. 

[grafspee]

19 minutes ago, Nealius said:

I fly everything from the ramp. Didn't think that would make a difference. We might also have to define what a "hot" day is, because 25C isn't hot. 28+ I'd consider hot. 

Exactly 25 isn't hot that much and P-51 struggling a lot. We don't have it in DCS but when coolant exceed 121C system will open valve which vents coolant out just next to rear exhaust pipe to prevent damage of the radiator from excessive pressure. So in RL this is RTB because all your canopy is sprayed with coolant. It is glycol so your visibility is reduced and it wont vaporize quick.

This is second attempt how i do it. pre open coolant door, reducing power to climb just after take off. Still coolant super hot. Apply power more slowly.

I don't know how you manage to stay at green at take off.

 

Edited April 10, 2021 by grafspee

[Sacarino111]

Hi.

To me, the AUTO doesn t work properly. I blow engines very easily, even when keeping an eye on the RPM and Manifold Pressure closely. So the trick of opening the radiators for take off/combat is the think that reconciliated me with the Mustang. Before,I couldn t understand how this plane could have gone so popular with an engine that finiky! I hated it! If I keep the RPM and Manifold to the charts, I struggle to reach enough air speed to cool it properly, so I bound the radiators to the HOTAS and I manage to keep the temps on the green. To me, a nightmare...

Saludos.

Saca111