Cant fly without breaking the engine

Hi, i want to fly this plane just for fun and chill, but im braking the engine every single flight:D

 

i start up the plane and taxi to the runway. on Start i set RPM to MAX and MP goes to 45

i get into the air without any problems. at 1000 to 1500ft AGL I decrese RPM to 21 (middle of the green bar) and pull the MP back so that the engine is capable to maintain RPM without much prop increase. that means MP is also in the first half of the green bar. at this setting, i mostly got 250knts and cruise around. there is not a single guage near a red line, all of them are well in the green zone but still engine crackles and its dead. no rpm increase no MP increase, it just dies. sometimes the prop brakes abruptly

 

what I tried:

toggle cooling off on the ground and activate it in flight - no effect

use ram air on the ground and switch to unrammed in flight -no effect

 

the aircraft is in a clean configuration with about 75% fuel

i dont know what i do wrong:(

 

EDIt: before i take off, i always make sure oil temp is ok and not too low

Edited September 6, 2019 by whaaw

Hi, i want to fly this plane just for fun and chill, but im braking the engine every single flight:D

 

i start up the plane and taxi to the runway. on Start i set RPM to MAX and MP goes to 45

i get into the air without any problems. at 1000 to 1500ft AGL I decrese RPM to 21 (middle of the green bar) and pull the MP back so that the engine is capable to maintain RPM without much prop increase. that means MP is also in the first half of the green bar. at this setting, i mostly got 250knts and cruise around. there is not a single guage near a red line, all of them are well in the green zone but still engine crackles and its dead. no rpm increase no MP increase, it just dies. sometimes the prop brakes abruptly

 

what I tried:

toggle cooling off on the ground and activate it in flight - no effect

use ram air on the ground and switch to unrammed in flight -no effect

 

the aircraft is in a clean configuration with about 75% fuel

i dont know what i do wrong:(

 

When you are in green at rpm and mp you should be ok, no matter is it low range rpm and high range mp.

Minimum t/o power is 50" irc 55-61" is preferable, it helps clean engine after long ground operation.

then after t/o you should reduce power to 46"/2700 and keep it for a while to warm engine up once you get decent oil temp you can reduce to cruise power. Radiator flaps should be in auto position. For t/o i open coolant radiato fully.

Before t/o you should warm up engine to 60 coolant and 40 oil,

When you get this engien problem in flight check fuel presure.

Remember that boost regulator is kicking in above 40" of MP, so when you fly at mp 30" you need to monitor your MP all the time. For exmaple if at 5kft you set 30" 2100rpm and you descent to SL you will end up with mp 40" and this may damage your engine while running 2100rpm.

but you need provide more data about your fligh

Is engien just quiting or jamming so prop make sudden stop.

Edited September 6, 2019 by grafspee

Reduce MAP before you reduce RPM; otherwise you are over-boosting the engine and causing detonation that will lead to failure.

 

When demanding more power increase MAP after increasing RPM for the same reason.

 

Wanna get slow? Throttle first to go.

Wanna get fast? Throttle up last.

Edited September 6, 2019 by DD_Fenrir

Reduce MAP before you reduce RPM; otherwise you are over-boosting the engine and causing detonation that will lead to failure.

 

When demanding more power increase MAP after increasing RPM for the same reason.

 

Wanna get slow? Throttle first to go.

Wanna get fast? Throttle up last.

 

oh yeah i missed that :).

Whaaw, if you set 45" and 2100rpm you will kill engine quite quick, i assumed that you did read manual.

Edited September 6, 2019 by grafspee

oh yeah i missed that :).

Whaaw, if you set 45" and 2100rpm you will kill engine quite quick, i assumed that you did read manual.

 

i did read the manual on the constant speed prop, but it still is most likely pilot error :D

 

why do you mean i kill the engine with these setting? the numbers aer from my head, as i already wrote in flight i keep 2100-2400 RPM and give MP until i reach the RPM and maybe a notch more MP. Both RPM and MP are then in the green zone

 

Reduce MAP before you reduce RPM; otherwise you are over-boosting the engine and causing detonation that will lead to failure.

 

When demanding more power increase MAP after increasing RPM for the same reason.

 

Wanna get slow? Throttle first to go.

Wanna get fast? Throttle up last.

 

that is good to know, thx for the reply

 

When you are in green at rpm and mp you should be ok, no matter is it low range rpm and high range mp.

Minimum t/o power is 50" irc 55-61" is preferable, it helps clean engine after long ground operation.

then after t/o you should reduce power to 46"/2700 and keep it for a while to warm engine up once you get decent oil temp you can reduce to cruise power. Radiator flaps should be in auto position. For t/o i open coolant radiato fully.

Before t/o you should warm up engine to 60 coolant and 40 oil,

When you get this engien problem in flight check fuel presure.

Remember that boost regulator is kicking in above 40" of MP, so when you fly at mp 30" you need to monitor your MP all the time. For exmaple if at 5kft you set 30" 2100rpm and you descent to SL you will end up with mp 40" and this may damage your engine while running 2100rpm.

but you need provide more data about your fligh

Is engien just quiting or jamming so prop make sudden stop.

 

also thx for this reply, after my first few failures i went extremly

carefully with RPM and MP, maybe to much?

 

normal failure for me is engine quits, makes a few noises and dies. prop still spinning.

yesterday while buzzing around Lasvegas i got the sudden prop stop for the first time.

i then watched the replay and everything was alright, the oil temp was at 85C° when the motor died. i know its a bit high, i was flying low and slow but 85 is still in the green bar.

Edited September 6, 2019 by whaaw

i did read the manual on the constant speed prop, but it still is most likely pilot error :D

 

why do you mean i kill the engine with these setting? the numbers aer from my head, as i already wrote in flight i keep 2100-2400 RPM and give MP until i reach the RPM and maybe a notch more MP. Both RPM and MP are then in the green zone

 

 

 

that is good to know, thx for the reply

 

it is all about how you change power setting after t/o if you reducing rpm and keeping this 45" MP you will harm engine and it will fail at some point.

it is all about how you change power setting after t/o if you reducing rpm and keeping this 45" MP you will harm engine and it will fail at some point.

 

ok this now makes sense to me. after take off first MP has to go, then reduce RPM. this is a good tipp, i will try this asap

i keep 2100-2400 RPM and give MP until i reach the RPM

Yeahhhh, nope :doh: . You're most probably overboosting.

 

The procedure is, in order to increase power, go first rpm and only then MP, while to reduce power go first MP, then rpm. If you use MP to get rpm while trying to get 2100, then rpm are waaaaayyyyyyyy low and MP definitely overboosting.

 

 

Instead of that, take off with full rpm (check 3000 in tachometer), 45-50" MP is fine if that works for you, no need to go 61" at all. Once airborne of course you can (and should) reduce power, and that means MP to a cruise, or climb, or whatever you plan to do, and only then reduce rpm to that MP you set. Those are 2700-46" climb and maximum continuous, 2400-36 or 35" for cruising (green MP). 2100rpm could be possible, but probably that means like 24-25" or something alike which is not stated in the manual. So you reduce to 46" (if you were 50 or more at take-off) and then and only then reduce rpm to 2700.

 

A constant speed propeller means governor will keep the rpm you set no matter what, so if you keep rpm lever who knows where and use MP to seek that rpm… engine is dead for sure. You have to see it like rpm you set is sort of a roof and MP can't go any further than the rpm you set (in the numbers said in the manual I told above, 27-46, 24-36, and so). So in order to keep the roof without crossing it MP goes first when reducing and later when increasing power.

 

And remember, don't brake the engine.

 

S!

Edited September 6, 2019 by Ala13_ManOWar

I dont understand this part that you applying MP to reach desire rpm. If i understand it right.

Let me say that RPM you control with rpm lever next to throttle, with throttle you setting MP.

You absolutely should not care about prop pitch, this will change during flight even if you keep same rpm and MP, your air speed has massive impact on prop pitch too.

For t/o Prop handle all way forward.

you should say something like this, I set my desire MP by throttle then i reduce RPM to optimal level.

You can use 2100 rpm with 36" boost no problem once you are in green every combination should be possible.

Edited September 6, 2019 by grafspee

no need to go 61" at all.

 

S!

 

I just love full power t/o in p-51

I dont understand this part that you applying MP to reach desire rpm.

He means he probably was doing so, and there's the problem.

 

 

With regards to high boost low rpm super economy cruising, yeah, that's a thing and can be done, but I think he should learn first the regular procedure, not to mention P-51 boasts such a good endurance it's a bit pointless to use those unlike the Spitfire in which those comes in very handy.

 

I just love full power t/o in p-51

Yeah, but you can live without it even taking off fully loaded, so for somebody learning it makes sense not to go full power until you tame it.

 

S!

2100rpm could be possible, but probably that means like 24-25"

 

Just an aside, but 2000RPM/30" does actually work as a cruise setting too, or at least did when I last flew the bird a couple of months ago.

Just an aside, but 2000RPM/30" does actually work as a cruise setting too, or at least did when I last flew the bird a couple of months ago.

 

you should be able to do 2100rpm 36' too.

I've never did that in game for long cruise so i cant say that im 100% sure.

i use max cruise 2400/2300 36'

i will test lowest rpm and highest MP for longer flight :)

Edited September 7, 2019 by grafspee

First thanks for all the replies. After spending some more time in the cockpit I think I got it right now. I took more time to warm up the engine and was more careful after takeoff

After taxi, I stood on the brakes and moved the throttle forward very slowly to get the temps higher before I let go for take-off.

Wanna get slow? Throttle first to go.

Wanna get fast? Throttle up last.

also helpt a lot.

 

I also changed the map, somehow on Las Vegas map the engine is more likely to break. At least for me.

 

Is it normal that after a flight the oil temperature doesn't go back at all? I landed with 82C° and it wouldn't go back into the green. rpm was min. and MP just a little bit

 

I dont understand this part that you applying MP to reach desire rpm.

 

as I understood from the manual RPM is only reached by the prop with sufficient MP. if there isn't rpm goes down

that means i set my rpm move MP slowly until RPM is reached and then give just a notch more pitch by moving the MP a bit further

Edited September 7, 2019 by whaaw

Just an aside, but 2000RPM/30" does actually work as a cruise setting too, or at least did when I last flew the bird a couple of months ago.

Thanks, will try that :thumbup: .

 

I guess if I convert Fenrir super cruise settings for Spitfire and use them in the P-51 they must work, but just didn't try yet. P-51 endurance is more than enough always till now, to be honest :D.

 

 

as I understood from the manual RPM is only reached by the prop with sufficient MP. if there isn't rpm goes down

that means i set my rpm move MP slowly until RPM is reached and then give just a notch more pitch by moving the MP a bit further

I think there comes the problem. It's more or less the opposite, the governor will keep rpm set for you no matter what and only will be unable to do so if MP isn't enough (see at take-off, rpm is set full, but you don't get 3000 until a certain MP). But try to see it the other way around, the MP range in which governor is able to keep rpm is, if I recall now by heart, way wider than the range in which it can't do so. That range is were you usually operate, with the rpm set being your roof as I said before. You have 3000rpm set? Then you roof is all of the throttle like there's no tomorrow. You have 2700rpm set? Then your roof is 46". And so on, 24-36, 20-30. What is important to understand in the end is, you DON'T set rpm, pitch or whatever, by using the throttle and MP, you do so with the rpm lever, then MP is used within the available range to those rpm.

 

 

S!

Edited September 7, 2019 by Ala13_ManOWar

 

I think there comes the problem. It's more or less the opposite, the governor will keep rpm set for you no matter what and only will be unable to do so if MP isn't enough (see at take-off, rpm is set full, but you don't get 3000 until a certain MP). But try to see it the other way around, the MP range in which governor is able to keep rpm is, if I recall now by heart, way wider than the range in which it can't do so. That range is were you usually operate, with the rpm set being your roof as I said before. You have 3000rpm set? Then you roof is all of the throttle like there's no tomorrow. You have 2700rpm set? Then your roof is 46". And so on, 24-36, 20-30. What is important to understand in the end is, you DON'T set rpm, pitch or whatever, by using the throttle and MP, you do so with the rpm lever, then MP is used within the available range to those rpm.

 

 

S!

 

yeah, I think I got it now, flew the whole weekend without a broken engine.

the definitiv trick was to bind oil and water radiator to my hotas. i can now fly forever on 2700RPM 46Hg i also managed to go to 30k feet multiple times without any issues. what i use now:

 

2700 / 46 take-off (i know its 3000 / 60 but even with bombs i don't need that much power)

2400 / 35 Auto Cooling / Cruise / climb max 500-800ft/min

2700 / 46 Manual Cooling / max Cruise / climb up to 2000ft/min

2700 Landing

 

thx all!

Edited September 9, 2019 by whaaw

as I understood from the manual RPM is only reached by the prop with sufficient MP. if there isn't rpm goes down

that means i set my rpm move MP slowly until RPM is reached and then give just a notch more pitch by moving the MP a bit further

 

But what is sufficient rpm heh this is question.

Sufficient rpm to hit target rpm will change a lot.

when you are on the ground with no air speed you will need a lot on MP gage to hit 3000rpm.

you can perform a little test, start t/o roll with 30' it will not give you 3000rpm but as you start gaining speed you will notice that rpm will go up too.

so in flight with sufficient airspeed you can cut thorttle completely and you will still be able to maintain 3000rpm.

So when you thinking that you adjusting throttle just to be at verge of set rpm you are far mistaken, once you gain speed this point will fade away and no thorttle setting will let you to drop rpm below rpm which you set by rpm handle. If you slam throttle fast you will see that rpm change but this is only due to acomodation speed of gavernor thats it.

So when you thinking that you adjusting throttle just to be at verge of set rpm

yeah thats what i understood from the manual, but i know now that this was wrong. when landing i do 2700 RPM and throttle goes to idle and i still have 2700RPM :)

yeah thats what i understood from the manual, but i know now that this was wrong. when landing i do 2700 RPM and throttle goes to idle and i still have 2700RPM :)

 

exactly, and when air speed drops below certain point rpm will start goes down :)(prop at this point is reaching its minimum pitch angle and is no longer able to keep 2700 rpm).

Similar situation may happen in extreme dive when gavernor will hit max pitch angle on the prop forcing engine overspeed, but this situation is probably not possible to happen in p-51 where designers make sure that overspeed wont happen from excesive airspeed, but overspeed still may happen is rapid dive acceleration where prop gavernor will not be able adjust prop pitch as fast as is needed, so combining rapid throttle movment with begining of steep dive from low MP level will most likely lead to extream prop overspeed.

And another info, Power developed by engine = more or less to inducted air.

So your throttle and rpm lever will change engine power. using throttle you will increase density of inducted air and with rpm lever you will control how often air/fule mixture is inducted to combustion chambers.

Both things if goes higher will give you more power.

Idea of low rpm and high boost is to let supercharger sping slower and high boost is for compensating for power lose due to low rpm and to use all of potnetial boost provided by supercharger with no need of cuting of excesive boost, this setup will make plane burn a lot less fuel extending range by lot.

Edited September 9, 2019 by grafspee

I have two last question regarding engine:

 

when do i use ram air or filtered air? as of now, I use filtered on the ground and takeoff and after takeoff i go ram air and don't touch it again. I read in the forum the lever has not a function ingame because its always ram air. (posts from 2013)

 

when do i use carb heat? i understood its used as de-ice but only when run on ramair, and not over 12kfeet because the mixture gets to lean. my carb temp is always in the green except when im high it goes down to -20C but the engine doesn't care as far as I can tell.

 

otherwise, I think im pretty good now in not breaking the plane.

I have two last question regarding engine:

 

when do i use ram air or filtered air? as of now, I use filtered on the ground and takeoff and after takeoff i go ram air and don't touch it again. I read in the forum the lever has not a function ingame because its always ram air. (posts from 2013)

 

when do i use carb heat? i understood its used as de-ice but only when run on ramair, and not over 12kfeet because the mixture gets to lean. my carb temp is always in the green except when im high it goes down to -20C but the engine doesn't care as far as I can tell.

 

otherwise, I think im pretty good now in not breaking the plane.

 

IF ram air is used(ram air lever forward) it uses ram air inlet visible under prop, at this position heat lever has no effect.

If you want tu use heat you have to move ram air lever back then you can engage carb heat.

Filtered position is used in dusty conditions,ground operations,etc. For t/o use ram air

Up high there is very little water in air, no need to bother with carb icing.

carb heat is used when flying in icing conditions(low temp,high humidity,snow,rain,clouds)

IF ram air is used(ram air lever forward) it uses ram air inlet visible under prop, at this position heat lever has no effect.

If you want tu use heat you have to move ram air lever back then you can engage carb heat.

Filtered position is used in dusty conditions,ground operations,etc. For t/o use ram air

Up high there is very little water in air, no need to bother with carb icing.

carb heat is used when flying in icing conditions(low temp,high humidity,snow,rain,clouds)

 

thx for your replys, i think im all on its way now to fall in love with this airplane. after all the jets I flown this is probably my jumpstart into the ww2 World. And i love it

yeah, I think I got it now, flew the whole weekend without a broken engine.

the definitiv trick was to bind oil and water radiator to my hotas. i can now fly forever on 2700RPM 46Hg i also managed to go to 30k feet multiple times without any issues. what i use now:

 

2700 / 46 take-off (i know its 3000 / 60 but even with bombs i don't need that much power)

2400 / 35 Auto Cooling / Cruise / climb max 500-800ft/min

2700 / 46 Manual Cooling / max Cruise / climb up to 2000ft/min

2700 Landing

 

thx all!

you can get away with 2700rpm46' t/o in game, irl it is just major safty procedure, taking off at 3000 50-61' is made for that once you lift off your engine is clean, any spark plug foul burned off you are at the same time testing engine "can he take full power"if not you have time to abandon t/o . you would not like to loose engine just after lift off.

p-51 manual advice, before landing and after long low power cruise, to crank up power to 61' 3000rpm for couple minutes to clean engine.

P-51 is totaly capable of climbing from SL to 40k ft at full power setting 61' 3000rpm it can do it at WEP rating 67' with no problem too.

Oil and coolant radiator flaps should be in auto position all the time even with WEP climb, they will open fully if required.

I dont know why lot of ppl want to maintain oil temp in green all the time, no realy point for doing that.

For me green line on oil works like engine check.

If im at cruise power coolant/oil flaps are set to auto and everything is in green i know that engine is in good shape, but if for example oil temp would be above green line, that would be indication of something wrong going on, it would alarm me.

Actual p-51 manual state that at wep power rating oil tem cant exeed 95 degrees for longer then 5 minutes.

if you are at 46'2700 oil temp should be just above green line or at very end same as coolant temps. Ofc we are talking about level flight not soem crazy climbs or dives.

Edited September 12, 2019 by grafspee