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Xiolablu3
01-26-2008, 06:54 AM
Could anyone tell me what was the usual time a plane like the 109G10/G14 could use MW50 for?

I have been reading about this just now, and it seems that the usual amount of Methanol-Water carried was enough for about 10 minutes of use.

In the sim I dont think it ever runs out does it?

WHy would Oleg strive hard to get other details of the sim so spot on, but give the MW50 unlimited use and also give the Spitfire WEP almost constant use?

I am thinking that boosts are highly over-used in this sim. They should be precious, as they were in real war-time.

Or perhaps we are just not that bothered to preserve the aircraft in the sim and the plane WOULD run for this long while boosted? Only requuiring a constant engine rebuild after every sortie? (unrealitistic)

Comments welcome..

Xiolablu3
01-26-2008, 06:54 AM
Could anyone tell me what was the usual time a plane like the 109G10/G14 could use MW50 for?

I have been reading about this just now, and it seems that the usual amount of Methanol-Water carried was enough for about 10 minutes of use.

In the sim I dont think it ever runs out does it?

WHy would Oleg strive hard to get other details of the sim so spot on, but give the MW50 unlimited use and also give the Spitfire WEP almost constant use?

I am thinking that boosts are highly over-used in this sim. They should be precious, as they were in real war-time.

Or perhaps we are just not that bothered to preserve the aircraft in the sim and the plane WOULD run for this long while boosted? Only requuiring a constant engine rebuild after every sortie? (unrealitistic)

Comments welcome..

Bewolf
01-26-2008, 07:35 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Xiolablu3:
Could anyone tell me what was the usual time a plane like the 109G10/G14 could use MW50 for?

I have been reading about this just now, and it seems that the usual amount of Methanol-Water carried was enough for about 10 minutes of use.

In the sim I dont think it ever runs out does it?

WHy would Oleg strive hard to get other details of the sim so spot on, but give the MW50 unlimited use and also give the Spitfire WEP almost constant use?

I am thinking that boosts are highly over-used in this sim. They should be precious, as they were in real war-time.

Or perhaps we are just not that bothered to preserve the aircraft in the sim and the plane WOULD run for this long while boosted? Only requuiring a constant engine rebuild after every sortie? (unrealitistic)

Comments welcome.. </div></BLOCKQUOTE>

MW50 had a total useage time of 10 minutes, but you could only run it on a couple minutes at a time. The modelling of MW50 in this sim is wrong indeed. It does eventually run out, but lasts quite a bit longer then just 10 minutes in this game. There have been several mails beeing adressed at Oleg from the german community to correct this, if I am not mistaken. CsThor or Frankyboy should be able to tell you more about it.

Kurfurst__
01-26-2008, 07:44 AM
10 minutes at a time. But you are incorrect in your basic facts..

Bf 109 K-4 Handbuch :

"Der mitgeführte MW-Stoff (75 Ltr.) reicht für 26 Flugmin.-Sondernotleistung aus. Es kann also 2 x 10 min Sondernotleistung entommen werden, oder eine andere Zeitaufteilung; auf keinen Fall mit Sondernotleistung über 10 min fliegen. Weiteres über Bedienung siehe L. Dv. T. 2109 K-4/Fl. Zwischen zwei Sondernotleistungen muss eine Betriebszeit mit geringer Motorleistung von mindestens 5 min liegen."

"The amount of MW booster fuel being carried (75 liters) is sufficient for 26 minutes of flight while using the Sondernotleistung. Therefore Sondernotleistung can be used for two 10 minute periods, or in any other subdivision; in no case should one fly with Sondernotleistung for over 10 minutes. For further servicing instructions, see L. Dv. T. 2109 K-4/Fl. Between two uses of the Sondernotleistung the engine must be run at a lower power output for ca. 5 minutes."

ie. 10 minutes at a time, but there is enough supply to run for 26 minutes on WEP while using MW50, if engine thermal load is not a concern.

The MW 50 tank had 118 liters capacity, for CoG reasons 70 to 85 liter of MW-50 was filled. 118 liter was allowed if the tank was used as an aux. FUEL tank (ie. density ~0.74 vs .98). The consumption rate was 180 lit/h on the G-10/K-4 w. the DB 605D, and 150 for the G-14, G-14/AS or G-6/AS with MW50 and DB 605 AM or ASM engine. Easy math.

Now, considering that 26 minutes at WEP equals an fuel consumption of 270-280 liters of fuel out of the 400 liter internal capacity..

I believe the only aircraft that could actually face a practical problem with running out of MW50/ADI is the P-47D with water injection, but I am not sure.

As far as the sim goes, of course Spitfires, officially limited to 5 mins at WEP can run on WEP indefinietely, late Bf 109s, FW 190s w. MW-50 etc, cleared for 10 minutes of WEP will overheat after 2-3 minutes and force you disengage WEP.

But you`re right that WEP is overused in this sim, however this is true for all aircraft. Real world pilots used Emergency powers much more sparingly.

luftluuver
01-26-2008, 07:48 AM
MW50 was fed at 150l/hr. How big was the tank? Should be easy to do the math to see how long the MW50 would last.

Some of the early 109s could only use MW50 for a couple of minutes but the G-6, on could use it for 10 minute periods with a 'cooling off' period between each usage.

see for engine specs, http://mitglied.lycos.de/luftwaffe1/aircraft/lw/DB605_varianten.pdf

Xiolablu3
01-26-2008, 08:14 AM
Thanks for the Info, however about Spitfires, Spitfire V models without the Auto-rads are limited to about 5 minutes at a time of WEP, as per the 5 minute limit given above.

Its the Spitfire IX's with the updated engine and auto-rads which run almost indefinitely on WEP.


As you have shown me that the MW50 is in fact pretty much correctly modelled (overheat after about 5mins, another 3-4 minutes before it ruins the engine)

Perhaps overheat IS modelled correctly after all. My findings were based on the fact that both overheat were modelled wrongly. I highly doubt if Oleg is correct with the MW50, he has 'fudged' the Spitfire IX WEP.

A different thought - WHy can almost all models of plane boost their engines to 110% + WEP, but the Spitfire is limited to 100%? And does this have anything to do with it not overheating as badly? After all the Me109 can run with MW50 at 104% indefinitely too.

Kurfurst__
01-26-2008, 08:22 AM
Most of these WEP limits were prescribed to save wear on engines due to the strong thermal/phyical load certain components would take if max power was used for a long time. The limits weren`t set in stone, and certainly the engines would not fail if they would have been run at WEP beyond the prescribed period; however, wear would accumulate faster over time, and eventually, engine output would slowly decrease, but nearly so dramatically as in the sim. Now, of course, the sim doesn`t model wear over time at all, so this 'Overheat' is kind of an artificially imposed limitation on players, so they would not run mindlessly on WEP all day.

I believe BoB will model wear over time for both airframes and engines.

VW-IceFire
01-26-2008, 08:32 AM
Nobody in the sim is worried about what the engine life is going to be 5-6 flights from the first and none of us have a crew chief to complain that the engine needs rebuilding either http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

Interesting information about the MW50! Cheers!

Brain32
01-26-2008, 09:56 AM
Ok I can't say I'm not heavily suprised by some comments here, especially since they come from il2 vets...

First total time of MW50 for in game late ME109's is about 20-25minutes, after that the MW50 is gone, but as soon as it is gone engine will be fataly damaged immidiately, coming to the full engine seize in about a minute.
But hey who flies one sortie for 25 minutes on a dogfight server right? Well me...

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content"> After all the Me109 can run with MW50 at 104% indefinitely too. </div></BLOCKQUOTE>
Again not correct, at the usual setting which is btw 103+mw50+rads auto, you will overheat not immidiately and not as insanely fast as on 110+mw50 but you will, in less then 10minutes too http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif

However if you go full out 110+mw50+rads closed your 109 will have completely destroyed engine in 10minutes, while IRL 10minutes was limitation for boost usage, not time to engine destruction.

Yes some boost systems are a bit overdone... http://forums.ubi.com/images/smilies/shady.gif

Jaws2002
01-26-2008, 09:58 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by VW-IceFire:
Nobody in the sim is worried about what the engine life is going to be 5-6 flights from the first and none of us have a crew chief to complain that the engine needs rebuilding either http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

Interesting information about the MW50! Cheers! </div></BLOCKQUOTE>

Exactly. You don't take up the plane and engine you abuzed last sortie. You get a new plane every time. That's why some of the real life limitations won't apply here.

Brain32
01-26-2008, 10:00 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Jaws2002:
Exactly. You don't take up the plane and engine you abuzed last sortie. You get a new plane every time. That's why some of the real life limitations won't apply here. </div></BLOCKQUOTE>
Bolded for truth, we sure have "the Chosen Ones"... http://forums.ubi.com/images/smilies/shady.gif

Xiolablu3
01-26-2008, 12:17 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Brain32:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Jaws2002:
Exactly. You don't take up the plane and engine you abuzed last sortie. You get a new plane every time. That's why some of the real life limitations won't apply here. </div></BLOCKQUOTE>
Bolded for truth, we sure have "the Chosen Ones"... http://forums.ubi.com/images/smilies/shady.gif </div></BLOCKQUOTE>

You mean like the best plane in 1940? The 109E? or the best plane in 1941? The 109F4? Or what about the joint best in 1942? The 109G2/FW190A4, Or the joint best in 1944-45? The Me262/FW190D? Yup the blue side certainly has some great planes....


I am not surprised at these comments from this long term heavily blue-biased IL2 pilot, but please dont turn this thread into the usual 'tit for tat' biased arguments.

We all have our slight biases, however hard we try not to, but I try HARD not to be biased, I am certainly not anti-blue, I love both sides planes. Kurfy's posts are sometimes heavily blue based, (and I am aware he hates me and the rest of the Brits http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif, no hard feelings mate http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif ) but he provides some great info, and I gain a lot of knowledge from reading some of his posts, and am therefore greatful and glad hes around. I forgive people like this, because they are such fans of the equipment, that they provide a wealth of information and are bound to have 'feelings' for the entity in question, otherwise they would not be such fans/experts. Trolls who make no effort to see their own biases, from BOTH sides just annoy me for their worthlessness and useless posts.

If you have some real life info on a certain plane, please show it, dont make troll'ish' comments with no real information...As I have read so many of your comments before, I know that you are heavily suggesting that the SPitfire IX overheat is wrong and blue planes are all undermodelled and hard done by.

As you seem so certain on things, can you show how long it took to wreck an engine on a Spitfire IX when he climbed at full power plus WEP in real life?

I seem to remember the main Spitfire IX test where it climbed at full power and never over-heated, only the auto-radiators opened, but I dont knwo if that was with WEP or not.

I am interested in facts only, I dont care which 'side' 'wins'. There are no 'sides' any more, only truths and non-truths.

Messaschnitzel
01-26-2008, 01:44 PM
I think I remember a thread(s) about a similar topic about this at one point or another.

I wonder what the actual results were like from engine to engine when using the recommended advice for boost usage. I know that many of the materials and methods that we use for bearings and seals today were not in use back then. For example, using poured babitt bearings and paper or leather for seals and gaskets.

It seems reasonable to conclude that even under ideal conditions, the engines would deteriorate and/or overheat when any type of boost is used within operational parameters. One engine might be able to perform to the full 26 minutes, and another may begin to overheat and break down a few minutes after the boost is switched on.

Another consideration is that a ground crew will be told to "make it work", when faced with a shortage of parts, sustandard or the like. This can include building up a number of sheets of paper to make a gasket, or rebuilding parts with worn out components. This can include reusing barrels with practically no rifling left to them during weapons maintenance.

I suppose that the pilot would have to trust that the entire operating system would hold under operating stress. I can imagine that whenever a pilot with any influence was transferred, he would do everything in his power to take his usual support crew with him.

Viper2005_
01-26-2008, 03:41 PM
The biggest problem with this debate is that "Overheat" in IL2 is a catch-all thing because the only things stopping you from running your engine flat out the whole time are (in rough order of importance):

1) Overheat
2) limited ADI in the aircraft which use ADI
3) Fuel in the unlikely event that you're range limited
4) Conscious

If you go into the IL2 model in detail, you will find that the Overheat model does bizarre things.

Overheat works with a timer. Once the warning comes up, the timer starts counting down.
Each aircraft has an "Overheat time".
If you run out of "Overheat time" then the engine damage sequence starts.

BUT

If you cool your engine down and bring up the "Engine Normal" message, the timer is reset.

So for example, I know that the overheat time in a 190 is about 5 minutes.

In combat I can therefore shut my radiator and run flat out until the Overheat message has been up for about 4 minutes.
Then I can open my radiator and close the throttle. At 0% power, the engine will cool down very quickly.

As soon as the "Engine Normal" message appears, I can close the radiator and slam the throttle back to MAX again. Of course, the Overheat message will come back very quickly. But I know I've got another 4-5 minutes before I have to cool my engine again.

I can keep doing this until I run out of fuel.

I can do this with any piston engined aircraft in the game, apart from those which use ADI (MW50, water etc), in which case the ADI will probably run out before I run out of fuel...

***

This sort of engine handling technique would very quickly kill a real engine due to thermal shock. But in IL2 it's basically the optimal strategy for extracting performance from your aircraft.

You've just got to learn the overheat time and get used to judging it...

The Emperor may or may not be naked, but he certainly spends a lot of time on nudist beaches.

***

Unfortunately, if you look at real life data, you'll see that overheating wasn't really a big issue, especially for liquid cooled engines, because it's quite easy to do the heat transfer sums and size a radiator, or decide how many fins you need to machine on an air-cooled cylinder to keep the temperature within limits.

So you might see overheating in a steep climb, whilst idling on the ground, or maybe in the circuit if the landing gear obstructs the radiator inlet (Spitfire).

But in high speed level flight there's no particular reason to expect it unless the designer was incompetent.

Generally speaking the limiting factors were mechanical, and perhaps the best mental model is one of fatigue. Each engine component has a "life". Operation at any given power setting consumes "life" at some rate which is a function of that power setting. Once a component runs out of "life" it fails.

Since not all components were created equal, the concept of "safe life" was created. This was a certain number of standard deviations from the mean life such that the probability of failure by the end of the "safe life" was acceptably low.

The rate of life consumption was calculated based upon an assumed sortie profile, and this resulted in an overhaul life in either logged flying hours or logged engine hours depending upon the type.

Deviation from the assumed sortie profile would set the cat amongst the pigeons because it might consume life far faster than expected, leading to failure in service, or it might consume life far slower than expected, leading to unnecessary maintenance action being conducted.

(Hence the attraction of "on-condition" maintenance.)

To account for this variation in the real rate of life consumption, the engine manufacturers were generally quite conservative in defining overhaul lives, and for this reason as well as due to improvements in the engine design resulting from the embodiment of various modifications ("Mods"), overhaul lives tend to increase during the course of any engine programme.

In addition, various limits were set in order to control deviation from the assumed sortie profile. Which is why you'll see various "time limited" ratings.

These limits were not generally set such that exceeding them would lead to immediate failure (though it might). In general they were set such that at the end of the specified overhaul life the engine would still be acceptably safe (i.e. "airworthy").

In the real world, abusing an engine early in its life might result in it failing on a subsequent flight under normal conditions.

As is demonstrated annually at Reno, if you're prepared to accept a greatly shortened overhaul life and a greatly increased risk of engine failure, you can actually push most of these engines far beyond the limits in the POH.

Because running engines to death is expensive, and because failures tend to fall along a random statistical distribution (Weibull distributions often work well*), it's rather difficult to produce a sensible model of the behaviour of a large number of WWII aircraft in a flight simulator, especially since as all the aircraft are modelled in "as new" condition, and we get a new one after every flight, the chances are that such a model would allow engines to sustain a level of abuse which would lead to considerable forum whine.

Unfortunately, the current model based upon "Overheat" leads to all sorts of misconceptions, and also in certain cases leads to unrealistic performance (e.g. consider the level speed performance of the P-51 with the radiator in AUTO...). Because not all aircraft are created equal in this regard, the current model leads to strange discrepancies in relative aircraft performance.

Sadly, attempts to explain these complex issues generally result in a flamewar (eg the P-47 performance thread).

Therefore I'm now retreating to my bunker...

* See http://en.wikipedia.org/wiki/Weibull_distribution

Xiolablu3
01-26-2008, 03:56 PM
Very interesting, thanks Viper http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

Brain32
01-26-2008, 06:03 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content"> I am not surprised at these comments from this long term heavily blue-biased IL2 pilot </div></BLOCKQUOTE>
Very convinient for you to say, this reminds me of lufluver's favourite saying, you know about the pot and a kettle... http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content"> We all have our slight biases, however hard we try not to, but I try HARD not to be biased... </div></BLOCKQUOTE>
Maybe you really do, but it definitely does not show http://forums.ubi.com/images/smilies/shady.gif

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content"> Trolls who make no effort to see their own biases... </div></BLOCKQUOTE>
You don't see your bias at all, it's pretty obvious from your statements that you are completely blind to your bias...

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content"> If you have some real life info on a certain plane, please show it, dont make troll'ish' comments with no real information... </div></BLOCKQUOTE>
It's highly interesting but I made far, FAR, more posts showing RL info and in-game tests than you did, so if my comments are "troll'ish'" what are yours then?

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content"> As I have read so many of your comments before, I know that you are heavily suggesting that the SPitfire IX overheat is wrong... </div></BLOCKQUOTE>
Considering what overheat means in-game yes I bloddy well do suggest that.

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">...and blue planes are all undermodelled and hard done by. </div></BLOCKQUOTE>
Highly generalized statements, I never even remotely suggested that. Also I find it funny how much support I had when I talked about how there's no base for Tempest overheating as hard as it did in previous versions(before v407), heck nobody even asked me for the data I made my claims on http://forums.ubi.com/images/smilies/16x16_smiley-very-happy.gif
Want to talk bias? Ok, I had no problems saying Tempest overheats too bad when it did, I had no problems saying P47 roll rate is off, I had no problems saying(and testing) that CW spits should be faster than full wings but aren't in-game, I had no problems saying D-9 '44 is too fast at altitude, I had no problems saying 109K4 climbs too good, I had no problems saying razorback P47's and P51's have bad gunsights, I had no problems saying P38 is hard done by in regards to compression at low alt, climb rate and that it's tail section is too weak.
BUT HEEEEEEEEEEEEY
When I said Spitfire doesen't overheat - WHAM!...insta-nazi, Tempest super turn - WHAM, FW190 gunsight - WHAM, FW190A series turn times - WHAM, 109 elevator and ridiculously weak DM - WHAM

Pure gold, well atleast I know what this forum is all about http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content"> I am interested in facts only, I dont care which 'side' 'wins'. There are no 'sides' any more, only truths and non-truths. </div></BLOCKQUOTE>
I agree but I sure as he11 do not see that here...

Ratsack
01-26-2008, 06:20 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Xiolablu3:
...
In the sim I dont think it ever runs out does it?
... </div></BLOCKQUOTE>

I recall somebody doing some tests in a previous version of the game, showing that it does indeed run out. Don't know how long it took, though.

cheers,
Ratsack

JG53Frankyboy
01-29-2008, 02:27 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Ratsack:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Xiolablu3:
...
In the sim I dont think it ever runs out does it?
... </div></BLOCKQUOTE>

I recall somebody doing some tests in a previous version of the game, showing that it does indeed run out. Don't know how long it took, though.

cheers,
Ratsack </div></BLOCKQUOTE>

as already mentioned - the MW50 runs out in the 109s after 26 minutes , in the 190/152s after 35 minutes.
in the Zero after 18 minutes (also used below 101% power setting).
in my experince it dont run out in the Frank, George, Ki-100 and Jack ?!?! (but , beside the Frank, i never tested it )

someone said in other topics it runs out in the P-47s (cant remember the time).

the whole CEM concept is sure simplified , its a game http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif , but better than nothing !!

Xiolablu3
01-29-2008, 10:56 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Brain32:

When I said Spitfire doesen't overheat - WHAM!...insta-nazi, Tempest super turn - WHAM, FW190 gunsight - WHAM, FW190A series turn times - WHAM, 109 elevator and ridiculously weak DM - WHAM
</div></BLOCKQUOTE>


I really dont have time to answer all your trollish comments,

however a few notes :-

I asked to see real-life SPitfire overheat figures in tests, if its wrong I will agree its wrong - No question. Just like as soon as some 109 experts pointed out that MW50 use is 10 minutes at a time, not 10 minutes overall. No argument, just accepted.

I dont think I have ever commented on the Tempest turn ever have I? Your imagination.

I have alaways agreed that the FW190A turn times are too low. Your imagination again.

The 109 Elevator WAS bad on late model 109's at high speeds, I have seen enough pilot opinions about it, however nor me nor you know how bad it actually was, so why pretend you do?

109 Weak damage model, its about the same as the Spitfire, maybe slightly weaker, it IS smaller and lighter after all.

FW190 view, have I ever commented on it at all? I may have done once to say that two pictures looked pretty much the same, thats it, not really 'WHAM' is it?



Are you confusing me with somebody else?



A little education here :- Having different opinions about planes is not being 'biased'. But always ****ging off the red planes, and always saying blue planes are hard done by IS. http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif You ARE the blue HayateAce on these boards.

fordfan25
01-29-2008, 11:40 AM
yea and mk108s are over moddled