Complex Engine Management & planes limits

[jf1981]

Hello,

I expect that through time, each single aircraft will start to have very good filght model & engine model.
In numerous airplanes, we have many gauges available, however it is not so easy to know which limits not to exceed to run the engine safely e.g. when to turn compressor on/off and how to set mixture up depending upon altitude, RPM limit, how much time allowable above certain RPM.

In other words, thanks to the packaging, we have a good Sptfire manual available with the game. But for other planes, will we have any documentation ? How do other people do ? Is there some good documentation about that on the web ?

I'd like to have a documentation of quality available with this game for each plane in the technical matter. Would that ever be possible ?

Regards

J.-F.

[Redroach]

http://lmgtfy.com/?q=he+111+pilot+manual

[jf1981]

First of all I'm not sure all of them are available in english, for exmaple the HE-111 you mentionned in your post.

Of course it will be possible to learn through time, I'm posting that to know if the technical documentation will be available through the game. It may not however.

[MadTommy]

There is soooo much documentation lacking for this game. We really should not have to find it from outside sources. Simulators should come with the info needed to master them, or at least explain the basics.

I really hope documentation will arrive in patches soon.

[Redroach]

if you are resistant to learn for yourself (not that I think that anyone would read a 500+ pages manual anyway), why don't you fly with CEM off then?

[Troll2k]

You would need over 200 manuals for IL2 1946.

[jf1981]

if you are resistant to learn for yourself (not that I think that anyone would read a 500+ pages manual anyway), why don't you fly with CEM off then?

I am not, I just keep burning the engines before I figure out what's happening, not a convenient way to learn.

I don't mean a full manual, key figures should be enough. It's like they are implemented but not documented.

I honetsly think it's not too much to ask for such.


You would need over 200 manuals for IL2 1946.

Of course not realisctic, just engine limits shall be enough.

I just discovered that Bleinheim IV mixture needs to be decreased progressivingly when getting alt but then the engine burnt for an unknown reason (oil & air rads fully open) ?

Just an example.

[Blackdog_kt]

Wall of text incoming...

Engine limits and where to find them:

The PDF manual is in (your games folder)\steam\steamapps\common\il-2 sturmovik cliffs of dover\manual
The section about aircraft operating limits starts with the Spitfire on page 83.

The Spit limits are probably the same as the Hurricane, because they have the same engines. At least i didn't have any problems whatsoever using the same settings on both: 2800 RPM for climb, 2650 for general use including combat, as low as 1800 for fuel economy cruise, the never exceed limit is 3000 RPM and i only use it during take-off.
As for the boost, it's clearly marked on the instruments with a red arc and a white triangle in the middle of it marking level flight power (which is probably max continuous setting).

This also goes for the Ju88 and He-111H, they have Jumo engines so you can use the same settings as in the Ju87, plus the Ju88 also has the limits clearly marked on the RPM and manifold pressure gauges with color-coded lines: green for continuous, yellow for combat/climb (probably a 30-60 minute limit on that one) and red for emergency.

The 110 also has DB601s but they are rated somewhat different than those used on the 109 so you can't use the values from the manual that refer to the 109. Once again though it's not a problem, because the limits for RPM and manifold pressure are marked on the instruments: d means continuous, 30 means "don't use it for more than half an hour" and 1 means "emergency power, don't use for more than 1 minute".
I bet the same settings will work on the He-111P as it has the same engines.


The only aircraft that completely lack any documentation are the radial engined ones: G50, Br20 and Blenheim.
These are a trial and error business with some interesting findings.

G.50 "glider":
For example, i was flying the G50 against some Gladiators in a QMB mission last night. At some point i was getting low on ammo and i had 3 of them swirling around me, so i got hit a couple of times but i didn't suffer any kind of serious damage. I decided to use my higher speed and disengage, so after forcing a sideways head-on merge i rolled level, put the nose down and turned for France, easily escaping them.

They were still following but couldn't catch me, in fact i was increasing the distance constantly. And then i had a "let's see what happens" moment and decided to do a little experiment. There was a cloud in front of me and i decided to see what happens if i fly through it. You see, there are no carb heat controls on the G50, so i assume it doesn't have such a device.
Sure enough, a couple of seconds before exiting the cloud my engine coughed, sputtered and seized :-P

The Blenheim:
The Blenheim is another tricky one, because it seems way sensitive to temp effects and especially having the correct oil temps. If your oil is cold, the oil pressure in the prop governor gets high and you get a governor failure.

Engine run-up:
Make sure to cycle the props between low and high RPM before applying power for take-off, as this will cycle the oil inside the governor and get warmed up oil from the engine into the system. This is called exercising the prop and is done during the engine run-up, prior to take-off.

Just keep the props at fine pitch, step on the brakes, full back stick, apply throttle until you get 1000-1500 RPM or so (arbitrary numbers, just something that won't break the engine from overheating while sitting on the ground and there's no airflow to cool it...in reality all aircraft have a specified RPM for the run-up) and move the pitch controls all the way back and forth a couple of times.

How the props work and how the game interface displays it:
As for the actual props now, it only has two-stage props but to put it in coarse pitch (the low RPM position) you have to pull the pitch slider all the way to the back. Anything higher than that puts it into fine pitch/high RPM. Effectively, this means that it has a prop similar to the one found on the in-game Spit Mk.I, but it doesn't "snap" between the two extreme positions (top and bottom) on its own. The bottom of the slider is the coarse pitch position, the rest of the slider all the way to the top is the fine pitch position.

Carburetor heating:
It does have carb heat but i haven't found any instruments displaying carb temps, so you need to read up a bit more to be able to set it.
You can't just set it to max either as it will reduce power, running too much heating lessens the air density in the carbs, so it's like running with too rich a mixture and choking the engine.

I've had some success setting it by ear, i just increase carb heat until the engines sound like they are losing power (this means i found the critical spot), then i decrease it a notch or two to get it back into the proper operating range and the engines sound healthy again. Had no problems up at 8000ft with this method last time i tried it in the free flight mission.

This is similar to leaning in an aircraft with manual mixture controls, which brings us to...


Setting the mixture:
First of all, there are two correct mixture settings for each altitude. The economy mixture is the leanest you can go without losing engine power, but it won't allow you to run high boost settings because of detonation and overheating. The best power mixture setting is a bit richer, burns a bit more fuel, but lets you run higher boost.

In modern and even not so modern general aviation aircraft, there are easy ways to set this: exhaust gas temperature and/or fuel flow gauges let you judge where is the correct mixture for each altitude.

In the Blenheim however we don't have those toys and we can't see the exhausts either, so we can't lean based on the colour of the exhaust flames.

Fear not, because there is a way. If you have a fixed pitch or two stage prop (which essentially is like having a fixed pitch prop that you can change mid-flight for another one with a different pitch) you can easily judge the changes in power.

This happens because for a given prop angle of attack, the power delivered by the engine has a direct effect on RPM. If your prop pitch remains constant, any change of throttle will change the RPMs too. In a similar fashion, every change of mixture that makes the engine run better or worse will also have an effect on RPMs.

This can be observed in aircraft with fixed props like the Tiger Moth (just lean until you get the highest RPM without touching your throttle), two-stage props and it would also work in aircraft that use the luftwaffe propellers, because they too are manually set to a specific angle by the pilot. It wouldn't work in an aircraft with a constant speed prop, because the resulting RPM change would be mitigated and cancelled out by the propeller governor, giving no useful indication to the pilot.

So, how does that help us with the Blenheim?
First, lean the mixture until you hear the RPMs increase. To know if you can lean further, keep at it until you hear the RPMs drop. This marks the point where further leaning doesn't yield any benefits, in fact leaning too much causes the engine to overheat.

So, as soon as you find that spot you've discovered the bottom of the useful mixture range for your altitude.

Go ahead and bump up the mixture towards rich a notch or two until the RPMs rise again. This is the economy mixture setting we mentioned earlier.

If you add a couple more notches of rich mixture (but not so much that it chokes and starts decreasing the RPM again), you will be at the best power mixture setting. This one is the best power mixture setting and it's the top of the useful mixture range for your current altitude.

In short, the scale looks something like this:
too lean---economy---best power---too rich.

Going too lean or too rich will cause your RPMs to drop, so just move the mixture controls until you find the range of highest RPM: the bottom of the range is economy mixture and the top of the range is best power mixture.

All this is presuming that the Blenheim has a completely manual system.

I don't know how exactly it works (is it semi-automatic between rich and lean like the Spit, or is it completely manual?), but if you try out the above method you can nail it down: if you don't see it working like i described, then it has a different system.

Also, just like in the Hurri, Spit and Tiger Moth, rich is backwards and lean is forward in regards to not only the animated cockpit controls, but also the info window sliders (the interface "HUD") and your actual, physical game controllers: you will need to press your "reduce mixture" key or pull your slider backwards to move towards richer mixture.

I've also found that the engines don't start easily if i set it to full rich, so i set it about halfway (if you look at the throttle quadrant, left-hand side in the cockpit, you will see a line marked as "normal" for the mixture controls, set it there). I guess full rich is only used when setting emergency and/or take-off/climb power to prevent the engines from overheating and cruising is done with mixture between "normal" and "weak".


Damn, you guys got me interested, now i'll have to go and test it all out ;)

[MadTommy]

Blackdog_kt thanks a lot mate.. invaluable information. :cool:

[jf1981]

Wall of text incoming...
[...]

Thanks for your post, in particular Bleinheim, I understand what could have happened, rads open, cold oil => failure

[Tex-Twil]

what does it mean when the Hurricane's engine is puffing black smoke from time to time ?

[jf1981]

Hello

With Bleinheim, I keep damaging the egine shortly after take off, eventually before I could eventually rool up to taking off speed.

I try running the procedure, warmin g up engine, I tried various sets of mixture and carburetor heat positions, fully open, fully closed, in-between.

I reach something like 200 to 250 °C for motor temperature, 50 to 60°C for oil temperature, 55 to 60 for oil pressure, apparently normal behaviour of both engines, mixture normal to rich, full rpm, full throttle, thin pitch.

I build up speed, eventually take off, then get oil leakages, engines loosing power.

[TeeJay82]

what does it mean when the Hurricane's engine is puffing black smoke from time to time ?

Its not burning the fuel correctly, most likely too rich mixture, or you apply too much negative G

[TeeJay82]

Hello

With Bleinheim, I keep damaging the egine shortly after take off, eventually before I could eventually rool up to taking off speed.

I try running the procedure, warmin g up engine, I tried various sets of mixture and carburetor heat positions, fully open, fully closed, in-between.

I reach something like 200 to 250 °C for motor temperature, 50 to 60°C for oil temperature, 55 to 60 for oil pressure, apparently normal behaviour of both engines, mixture normal to rich, full rpm, full throttle, thin pitch.

I build up speed, eventually take off, then get oil leakages, engines loosing power.

OIL RADIATORS - FULL OPEN
ENGINE COWL FLAPS - FULL OPEN
MIXTURE 100%
PITCH 100%

apply throttle slowly and watch so your manifoil pressure doesnt go over the maximum recommended value

[jf1981]

Hi,

I seem to have burnt the engine flying at 19'000 ft simply after pushing up the power a little bit. True the oil temp was only 40°C and pressure a bit high 75-80 lb per sq inch.

I could manage to get running, but apparently, if one gives the engine full power for a while, it will not last long.

Not an easy plane to fly !

[Blackdog_kt]

At high altitudes you can close your cowl flaps a little bit (especially if on moderate power settings), since the outside air is cold enough to provide a more pronounced cooling effect.

Radials are reliable and resistant to combat damage but they do have a high workload. Imagine flying a P-47 with CEM: throttle, semi-automatic mixture, prop pitch, cowl flaps, turbo-supercharger, intercoolers (like carb heat but they can also lower the carb temps instead of just raising them) and oil coolers.

Generally speaking, 220-250 is the highest your cylinder head temp should be allowed to reach. On the other hand, if you want to apply power and its below 200, you would be well advised to apply it gradually so it has a chance to warm up, or momentarily close the cowl flaps a bit and open them again after increasing power.

[Skiiwa]

Awsome Info In this thread!

[2GFlea]

The files linked in this thread might help some.

http://simhq.com/forum/ubbthreads.php/topics/3269457/2GvSAP_Flea_s_Data_Sheets_for_.html#Post3269457

[jf1981]

Hi

Regardnig Bleinheim IV, I could now start and fly, the main thing being not putting too much power until it reaches 200°C, then never nuder any circumstance let the temperature rise up to 250°C.

In spite of this, when reaching up to 16,000 ft, the engine will start to have problems anyway.

Is someone able to fly up to the limits ? How high can safely fly this plane ?

[Blackdog_kt]

I've been looking for a pilot's operating handbook but i've been unable to find a free version of one. I'll check and see if Flea's datasheets on the simHQ thread contain any information for the Blenheim's operating limits.

That being said, if you get sputtering engines at high altitude try giving it some carb heat.

Also, if you get engine damage during takeoff or when running high boost make sure you really are running rich mixture. It's reversed like in the Hurri and Spit, full rich is with the levers fully back.

I do know how it works more or less but i still damage the engines from time to time, it's a very challenging aircraft with a lot of stuff to keep in mind. The fact that there's no carb temp indicator further complicates things, because you have to more or less guess when and how carb heat to apply.

[MD_Wild_Weasel]

hi guys, very interesting reads. 2 things regarding the Blenheim and full CEM........
1) Has anyone elses CEM controls on the bottom left hand side dissapeared?
All i have left is the throttle controls. PP, Carb heaters and mixture sliders have all gone. :eek:
2) Finnaly got her off the ground and flying sweet till i go through a cloud. Then my windscreen freezes up and the revs fluctuate and die. Cloud level is about 2500ft. I manged to recover engine stability by dropping almost to ground level(once). How can i combat this? Sorry im not a pilot so this is a steep learning curve for me if this is a stupid question.

cheers

[Seeker]

hi guys, very interesting reads. 2 things regarding the Blenheim and full CEM........
1) Has anyone elses CEM controls on the bottom left hand side dissapeared?
All i have left is the throttle controls. PP, Carb heaters and mixture sliders have all gone. :eek:
2) Finnaly got her off the ground and flying sweet till i go through a cloud. Then my windscreen freezes up and the revs fluctuate and die. Cloud level is about 2500ft. I manged to recover engine stability by dropping almost to ground level(once). How can i combat this? Sorry im not a pilot so this is a steep learning curve for me if this is a stupid question.

cheers

Bearing in mind I'm still working on getting off the ground....

The CEM controls are part of an "info window". You've managed to close it some how, but you can make a new one, and it's up to you if you want a grphic showing control positions or just % numbers.

Your engines died in the cloud because your carberetters froze in the cloud - you have to heat the carbs, and the controls are down by your left hip behind the pilots seat, you'll have to wiggle a bit as a Track IR user to see them.

[MD_Wild_Weasel]

cheers for that Seeker, I will have to bind a key for the carb heaters as as you said they are a pain in the behind to get to! LOL.
What about the windscreen freezing up? is there a key?

[Seeker]

cheers for that Seeker, I will have to bind a key for the carb heaters as as you said they are a pain in the behind to get to! LOL.
What about the windscreen freezing up? is there a key?

Check you've got the Z axis enabled in Track-ir, then lean forward and breathe very hard on the screen.

This only works if you've got FFB enabled..

[naz]

Check you've got the Z axis enabled in Track-ir, then lean forward and breathe very hard on the screen.

This only works if you've got FFB enabled..

LOL! That made my day.:grin:

Great info in this thread too lads, thanks a lot!

[MarckCargo]

I don't know weather is it like by all of you guys or not but I love the wing design for complex engine planes. Wing design in Flight cycle limits is always my first attraction.

One more thing for Redroach, leaning is process of success that is never ever stop. We just need to open our self for learning every moment. You are so right we don't have to resist our self for learning.

[TomcatViP]

Great post. My best read since long on this Forum (including my own post :( ) - Thx BlkDg

As there is no warm air being vented in the 'pit I wld suggest to open the side windows once out of cloud.

@Seeker :mrgreen::mrgreen: