Wep and cooling.......

[hazed-]

thanks mandoble that helps  
 (i was beginning to worry i was speaking some form of ancient celtic dialect )

Ive tried to say it as clear as i can.

[Wilbus]

I think the only plane we have in AH that is actually modelled with MW50 is the Ta152, Pyro said in a Ta152 thread it is Mw50 and it can also quite clearly be seen on the extra performance gained when you look at the AH charts. However, as it IS modelled in the Ta152, the Ta152 should have 10 minutes WEP and 5 minutes Cool down time HiTech, there is quite much eveidence of the MW50 being used like this, pilot reports aswell as other reports. Any way you can modell it like that?

As for the other planes we have, I don't think they are modelled with MW50. MW50 gave much better performance then just normal WEP and can be seen on the Charts. The Dora we have is most likely the 1900 HP version and not the MW50 equiped 2,200 hp.

I don't think the 1900 HP version used MW50.

[hazed-]

Originally posted by Bombjack
Since the G10 and D9 are completely different aircraft, there is no reason I can see to suppose that their WEP systems should be modelled identically. HT has said that the modelling is a necessarily compromised abstraction of reality, and this kind of analysis is therefore rather futile.

er couldnt the same be said for :

P51d
P47s
P38s
spitfires
la7/la5s
Niks/zeros

all i believe 5 mins wep 10 mins cooling?, all with COMPLETELY different engines and cooling systems

among others! but i havent tested all but then it isnt really down to me to test every plane in the game is it?

seems to me bombjack you know nothing about this system either.You merely have taken offence to this post because it questions an aircraft you associate with Luftwaffe types.You havent read what ive posted or tried to grasp the reason behind the question.You have just 'stuck your oar in' and tried to have a bash at me.

as to the 'necessary compromise of reality' and it being futile you are completely wrong.The point here is this:

either the LW Mw50 has been modeled into the equation fairly or it hasnt.
If you read back and visit the site ive posted it says the La7s could run on wep for only 30 seconds
Someone else said the pilots handbook on p47s and p51s says it could run from 3 to 5 minutes on wep
German litrature says 2 to 20 minutes with MW50 (book quoted in this thread)and 10 minutes on with GM1 nitrous and 5 minutes cooling before it can be used again fro 10 minutes up to a total of 43(from memory) minutes using this on off method.
if all engines in emergencies could be run ntil they blew surely those with water methanol or liquid cooling would run longer if run indefinately at high explosive tempretures? the methoanol whilst it lasts would help protect the engines right?
so in a game where we have to decide on some form of limit surely all should run up to that limit and cool at basically the same rate?(air cooled should be less efficient of course and if we can find information on the efficiency differences between liquid cooled systems then by all means factor that in) only those with extra systems(water methanol/nitrous) should gain extra bonuses ie slightly longer wep.the cooling aspect is what is the most confusing part here.Seems to me the limit mentioned in these books is the one recommended because further use causes damage/wear and tear maybe seizing?.If we have to impose a limit for the games sake surely the damage/wear/seizing aspect would make more sense.

now you tell me now , IF these things are TRUE this would not affect combat in WW2?

I CANNOT confirm this information is true that appears in the many books you can read.and i suspect HTC had the same problem.
Thus being unable to confirm the running tempretures or actual time the MW50 etc really had?, having no charts etc ? maybe HTC were right to use the system we have BUT are we never to question it? is it to be ignored forever more until some data does turn up? we must ignore all the quotes from actual WW2 pilots and some manuals and handbooks in favour of HTCs best guesstimate?

i hope you too can now understand finally why this was asked.
I want to fly these planes in combat exactly as they were if it is at all possible.Thats the whole appeal of this sim for me personally, how about you?.

like i said before if it turns out thats the way it has to be because thats the way HTC wants it then ok fair enough i'll play it for how it is, but i'll no longer feel it it a totally accurate representation.Im sorry but i prefer to believe what was on the manuals over the best guess a person can make some 60 years later.I should not be insulted for saying this either.I think they wrote those things in their documents for a reason and they were probably wep times recommended to avoid engine damage.

seems to me all countries made pretty good engines so for the sake of a game we can assume they all have pretty much the same lifespan if used within 'recomended' limits otherwise why did they bother recomending limited times for wep use at all? I think they probably ran tests with wep on full and found the engines seized or became damaged and lost power or something and forced them to recommend only certain durations in order to keep the thing flying longer and keep pilots alive.If we now have the arguement that if a pilot really wanted to he could run on wep for an indefinate period then it applies to every aircraft and therefore doesnt need to be factored in at all.I think if its to be fair the only thing that should affect the length of wep is the 'aids' that boost the engines and allow longer use of wep without considerable damage and their limit on fuel/specialised fuels(ie nitrous) capacity.I dont see how anything else could be a factor.Longevity of an engine used within its limits is pretty much the same.If you dont think so explain why we still have so many working original warbirds today some 60 years later?.And as for overuse in emergencies meaning 'some' could wep indefinately 'so it can be argued a select few aircraft could run almost indefinately' then this must also apply to all engines pretty much.If you dont agree on that, what information would you base the arguement on? books that mention their reliability? or the ol' pilots hanbooks? you see? if theres charts then FINE fair enough but it appears there isnt.

something made HTC decide these times and all thats asked is what it was.

[hazed-]

!!

Originally posted by Wilbus
As for the other planes we have, I don't think they are modelled with MW50. MW50 gave much better performance then just normal WEP and can be seen on the Charts. The Dora we have is most likely the 1900 HP version and not the MW50 equiped 2,200 hp.
I don't think the 1900 HP version used MW50.

now this is confusing, so why do LW planes have 10 minutes rather than 5 minutes wilbuz? did they have normal wep that was able to be run for 2x the length of other WW2 aircraft?

if not  to 'factor in mw50' why do we have 10 minutes?

and also if it isnt 'factored into the model' WHY no mw50 on the dora / 109g10 /190a8 etc? its pretty clear they had them given that RAF tests state most of those captured examples had it?

this gets more even more confusing !!:confused: !!

[john9001]

check my post on the merlin eng , it used water/methenol injection also, ......soooo
44MAG

[hazed-]

Originally posted by john9001
check my post on the merlin eng , it used water/methenol injection also, ......soooo
44MAG

well then thats another one to question. id check how much methanol it carried and see if it is the engine modeled in AH.
If it turns out it had quite a bit that might justify a similar amount to Lw planes maybe there is a basis to ask for an extended wep capability.

Unfortunately as i still dont really know why the times are set how they are,( most of my ideas on why they gave LW extra wep seem to be wrong if wilbuz is correct about no mw50 being modeled).I have to say it, i just dont get it.the basis for HTC's decision on the times they did choose may not have anything to do with water methanol at all it seems.I can understand that in real life a pilot could run an engine until it just blew which could make an arguement for unlimited wep but if this was the case for ALL aircraft why do we have differing times? doesnt make sense at all.

basically you got me john! I had no idea why its like it is and i stilll dont

btw could you do the tests for spits in AH?

so far just these ive retested properly offline to make sure i got it right:
190a5 10 mins 20 mins
190d9 10 mins 20 mins
p51d  5 mins 10 mins
hurri C 5 mins 15 mins
109g10 10 mins 10 mins
109g2 10 mins 10 mins

the spit with merlin 61, im guessing, is 5 mins wep on 10 mins cool as ive flown them a bit and thats what ive assumed but if like you say, it had methanol, who knows maybe it is already modeled with longer wep by HTC. I guess I will end up having to test all of them but id hoped others would do it too to save me the trouble (like them doing italian and japanese and russian planes etc.) its dull and time consuming though.

[Bombjack]

Hazed,

I fear it may be pointless trying to debate this subject with you, since you clearly reached your conclusions immediately and are now merely trying to work back to the proof.

I make no claims of special knowledge in this area, but I would suggest that, if anyone intends to continue this argument (although I would advise against it, since HT's intervention has made it moot), they first check that they understand the following related issues:

1) What is water/methanol-water injection? How exactly does it boost power, and how does that differ from other types of emergency power?

2) What was the purpose of the posted limit times on emergency power usage in pilot's notes? To what extent were they literal indicators of performance?

I doubt that you will take this as anything other than another personal attack, since you clearly see bias in anything I write.

John9001,

As far as I know, water-injection for Merlins was experimented with but not used during wartime. Certainly the planes currently in AH did not have it. N2O (GM-1 as the germans called it) was used operationally by Mosquitos (but not the FBVI afaik).

[Naudet]

Folks you all are way way to far going into speculations.

You know i am the 1st to stand up and argue pro-LW and in the past i have supported my arguments most times with charts etc.

But in regard to cooling, there are no hard facts (OK i have posted the temperatures for a JUMO213, so HT could model a correct gauge, but hey, nowhere in the handbook the cooling times were mentioned) about engine cooling.

All WEP times we have are "cleared" WEP times. This means an institution (for LW the Rechlin Test Center) has test i.e. the MW50 injection on the D9 an cleared it for 10mins use at a time, cause test revealed that the engine would normaly survive that without damage.

But in the fight, noone actually had a limited WEP time, the limit was what the engine could take.
There are multiple stories from both sides, were a pilot in emergency ran the engine on WEP for much longer.

And cooling down is a similar thing, as most aircraft have different radiator flaps settings (at least FW190 has), this means the pilot could influence the cool down rate by ajusting the rad-flaps manually.

Wide open rad-flaps would cool the coolant much faster than close one.
But wide open rad-flaps would also bring more drag an cost a few mphs speed.

And as HT didn't model a complete engine physics model, he had to make gameplay consessions.

I can ensure that i am pretty pissed that this leads to an drawback for the D9 (from my viewpoint), as the WEP system the D9 had was one of its strength, that made it the exellent plane it was.

[Bombjack]

Good points Naudet. As an illustration of how tremendously complex this issue is, I am once more indebted to Mike Williams' site which contains this test report .

The test was conducted when the Merlin 45 in the Spitfire MkV was rerated from +12lb boost for emergency power to +16lb boost. This in itself raises one point: engines could be rated conservatively for emergency power when first introduced, and later rerated when they showed themselves capable of enduring greater stresses (and/or as in this case, the need was pressing).

You can see from the report that the proposed rated limit on the new wep was 3 minutes, this is what would appear in pilot's manuals. However the test itself ignored these limits, using full wep for over 10 minutes without exceeding normal operating temperatures for the northern european summer climate it was conducted in. It is unexplored whether any overheating at all would have occurred at the old rating of +12lb, but it seems doubtful.

So, from this single test report, we see that:

1) Engines could be conservatively rated initially then see rerating.
2) The climate and time of year of the flight were highly significant.
3) Pilot's manual ratings could have little relevance to the engine's actual capability on any one flight - they had more significance as an attempt to reduce maintenance requirements.

Now see the impossibility of finding this level of detail for every aircraft in the game, and  consider HTC's problem in WEP modelling.

Perhaps all aircraft should have the same WEP limits, to remove this as a source of controversy?

[HoHun]

Hi Hazed,

Quoting "Die deutsche Luftfahrt - Flugmotoren und Strahltriebwerke" by Kyrill von Gersdorff, Kurt Grasmann and Helmut Schubert (ISBN 3-7637-6107-1), p. 81:

"The Jumo 213A-1 had a normal take-off power of 1285 kW (1750 PS). By applying a conversion kit an emergency power of 1395 kW (1900 PS) could be generated by increased boost at altitudes of up to 5000 m. Another increase of power to 1540 kW (2100 PS) was possbible by the installation of a 'special substance system' for methanol-water injection (MW-50). The associated boost increase was +0.28 bar, the time of application was limited ot 10 minutes, then 5 minutes at normal power had to follow. The MW tank of the Fw 190D-9 had 115 L content and sufficed for 40 minutes of operation using 'special emergency power'."

(Original is German, my translation.)

In WW2, von Gersdorff was an engine specialist at the RLM. Grasmann was conducting engine tests at Rechlin. Karl Prestel worked at BMW and was involved in the development of the Kommandogerät and the BMW jet engines. After WW2, they all continued careers in the aero engine industry. (Schubert, who pursued a similar career, was born in 1935 and does not have the same direct experience with WW2 engines as the others.)

In short, the authors are top experts :-)

So, unless the Aces High Fw 190D-9 doesn't have MW50 at all, it certainly should cool down in half the time required to heat up, not vice-versa.

Regards,

Henning (HoHun)

[hazed-]

bombjack im sorry but im getting tired of trying to explain to you what im asking.
I know what you are saying:

engines were rated at one level at one time and a higher level at other times right?
well my point would be this:
couldnt that be said for any WW2 engine?(doesnt this make it a pretty mute point?)
we have models in this game based on a certain performance chart for climb,turn,wep power etc right? so in those charts there is 'usually' a listing of the manifold pressure or boost level used during those tests.why arent these levels used as a basis for the levels in the game?? if they are then whats the point in pointing out what you are saying?

you've shown what i would have said is fairly good evidence that the spitfireIX merlin61 was run at 16 boost and wep at 18 for 3 minutes max. It would seem that is the model used in AH as ive just been to test it.Heres result:

SPITFIRE IX:
normal running boost full speed at sea level 16 boost
WEP power 18 boost
WEP duration 5 minutes
COOLING back to normal tempreture 15 minutes.

so we have revised list:

190d9 10 mins wep 20 mins cooling
109g2 10 mins wep 10 mins cooling
109g10 10 mins wep 10 mins cooling
HurIIC 5 mins wep 15 mins cooling
SpitIX  5 mins wep 15 mins cooling
P51d  5 mins wep 10 mins cooling

my theory was 190s and 109s got 10 mins because of the exceptional amount of fuel for mw50/gm1 they carried.190s taking longer to cool because they used to have heating trouble.I had assumed all others were 5 mins wep with 10 mins cooling (unless older aircooled types) but i was wrong.After the tests I merely asked so that i could understand exactly why they were the way they were.I knew the dora was liquid cooled inline and had assumed it would have cooled better than the aircooled radials of the 190A/F models.seems HTC doesnt.

now i guess the answer could be the gauges on the 190d9,spitfireIX,Hurricane etc are all reading wrong? perhaps HT could.. "change the gauge to read higher on the so it looks like it's cooling the same rate as the p51. But in the end all that would change is the lable on the dash board." but like ive said i cant understand quite what this means. maybe you do bombjack? Seems to me if they are just displaying wrong it still means it is making flying them and using the wep a rather awkward prostect doesnt it? Im sitting there waiting for it to cool when it already has? if they read right then my timings are correct.

anyway this is like beating my head against a brick wall and ive had enough of it.

this is the last time ill be in here to ask:

'why is cooling times set up in AH the way they are? on what basis were the times decided?'

thats it

[Furious]

Hazed,

First let me apologize if I repeat something already said.

Now, if you look at my first post in this thread you will see, I light of what HT has told us, that though I was posting tongue in cheek, I was pretty close to the answer to your question.

Each plane that has wep in the game has a specific amount of time that the wep will run per flight.   I am assuming that the time limit is based on amount of anti-detonate carried or on some maintence schedule requirement devised by HTC.

No matter how you work the throttle, the total duration of wep per flight is going to be the same.

The engine cools at whatever rate is necessary to comply with limiting the wep to that specific amount of time.

It is not an issue of relative cooling performances between the aircraft.



....of course I could be entirely wrong, but this is the impression I get from HT's posts.



F.

[Bombjack]

Furious,

I agree that the WEP modelling in AH is clearly time-based. The only datapoints we have are duration (of continuous WEP) and delay (before engine cools to normal). Since these all hit fairly broad figures (5, 10, 15 minutes) it is obvious that these were the chosen datapoints, and that WepHeatPerSec and WepCoolPerSec (see HT's code, above) were chosen to match up with them.

Hazed,

I apologise if I have unintentionally frustrated you, or wound you up. I agree that the wep/cooling times seem a little arbitrary, but I think HT has already answered your question with "because it seemed reasonable". Not altogether satisfactory perhaps, but it is nonetheless an answer.

If we wanted now to go further and argue that one particular aircraft is being disadvantaged over others by the modelling as it stands (as it appeared, earlier, you wished to), that is when all the complexity and uncertainty I talked about before comes into effect. It is, in my view, very near impossible to find out where every aircraft stands in relation to every other in this respect. HTC seem basically to have taken an educated guess, and that is IMHO the best anyone can do.

That is the situation as I see it: a 'best guess' is all that's achievable. We can present all the data we can find and if HTC did not have it previously, maybe they will think a slight rejig is in order.

The other points you raised are more technical, and I'll add what I can:

engines were rated at one level at one time and a higher level at other times right?
well my point would be this:
couldnt that be said for any WW2 engine?(doesnt this make it a pretty mute point?)

That certain engines are known to have been rerated over their lifetime in no way implies that all engines were. This point was meant to illustrate the great uncertainty with using pilot's manual ratings as a basis for simulation, since such ratings address many competing concerns.

my theory was 190s and 109s got 10 mins because of the exceptional amount of fuel for mw50/gm1 they carried

I think that these aircraft have a higher duration limit directly because of their pilot's manual ratings. As I showed above this is a poor referent, but HTC may have found it compelling enough to put it in, perhaps simply for the purposes of making a distinction between types.

I do not intend to go into how water-injection or N2O works here, but I will say I think you have a false impression of how the various types of 'emergency power' relate to one another.

"change the gauge to read higher on the so it looks like it's cooling the same rate as the p51. But in the end all that would change is the lable on the dash board." but like ive said i cant understand quite what this means. maybe you do bombjack?[

No, I admit this one kind of had me stumped, too

[hazed-]

bombjack my appologies for becoming a little defensive.force of habit im afraid.

as to what you summed up yes thats basically it.

but without HT defineing for us how they made their guesstimates we will never be in the position to question how the wep system works.
When i said earlier that there are certain aspects of AH that appear biased in favour/against certain aicraft i have to say this is one such area where i feel the setup in AH fares unfavourably toward the dora.
Of course i wasnt aware and i still dont know if its true that the mw50 hasnt been factored in or indeed modeled at all.
seems to me in every book ive read about the 190s the mw50 is mentioned again and again by the pilots who emote great praise for it.If we seem to be flying a game without it im severely dissapointed.
Like i said i was under the assumption that HTC had agreed the LW planes had great engine systems and had added 5 mins of wep as a compromise.And i do mean compromise as for all intents and purposes it would appear they had far more than a mere 5 minutes extra.But I was more than happy with it because i could appreciate their problem concerning modelling it.When i realised it takes twice as long to cool and not just a touch longer I was struck by the thought that 5 mins wep and 10 mins cooling or 10 mins wep and 20 mins cooling amounted to the same thing! I suddenly thought well where is the bonus in it? wheres the attempt to model the quite substantial amounts of (mw50/gm1) fuels they carried?
even worse as furious points out if you look at the total time of flight as the guide the dora fares even worse against the p51d:

MA flight time for aircraft with 100% fuel +DT:
190d9 = 51 minutes
P51D = 85 minutes
which means during a complete flight you can use wep/boost for a total of 20mins whereas the p51 gets to use its wep for nearly 30 minutes. it is a considerable advantage if you wish to stay at high alts for long periods which many do in AH.
the same thing could be said for the poor old spit9 pilot who fares even worse.with a full fuel load (56mins)a spitfire pilot can use his wep close to 3 times which works out 15mins total boost time in any one flight.(109g10 gets 20 mins wep total<43mins total flight time>). BTW im not sure how the extra consumption of fuel whilst wepping would affect these calculated times.

Whatever way its been worked out, and i might be wrong here, and if i am im sorry but it seems to favour the P51 or the planes with nice fuel loads which i dont really understand the reason behind it.If it was worked out that each aircaft had a proportionate amount to its total flight time i guess it could be argued it penalises the aircraft with greater endurance but as it stands it seems if you want to rule the high alts the p51 is the aircraft to use.

But without knowing the reasons its all conjecture i guess and i may as well give up but like i said to HT he should be aware certain areas of AH 'appear' to be biased.I could be totally wrong and falselt thinking this and i can honestly say id like HTC to show me ive got the total 'wrong end of the stick' but as they dont seem to want to give any explanation other than 'it was reasonable' im afraid ill make up my own mind on it.

Im going to stop posting in this thread now as it makes me more annoyed each time i read over it   . its just not worth the time is it?
Thanks mandoble,wilbuz,naudet,ho hun,furious,john and bombjack for adding info etc and not turning this thread into the usual namecalling threads which bore me to death
oh and HT , thanks for coming in here and trying to answer me but im afraid i didnt grasp all of what you meant.

[john9001]

the P51 was designed as a high alt long range A/C.

what was the fw190 d9 designed for?