Wep and cooling.......

[straffo]

Originally posted by hazed-
straffo this isnt a request for true engine management.The way wep works is a fine compromise ie all aircraft with wep have roughly 5 minutes before they reach critical temprature of 130 degrees or what ever then they take 9 minutes to cool down and away you go again.
HTC decided it was fair, seeing as how LW 190s had twice the amount of fuel for their boost systems as the average Allied plane, that the 190 could have 10 minutes boost.

BUT they then decided for some inexplicable reason to double the length of time it takes for it to cool down.THUS making the fact that 190s had more fuel for boost pointless in some respects.

Perhaps the same rule is used for the increase and decrease of temperature ...

I need to test a bit to form my opinon on this

[john9001]

the P51 did not use "boost fuel" it had a throttle stop to limit manifold pressure, the stop could be overridden for WEP, the only limit on "WEP' for the P51 was eng temp , too much use of WEP would shorten time to next overhaul.

so when your dora ran out of "boost fuel ' the P51 would catch you and shoot you down as they did in real life.

[TBlayde]

Hazed,

My Understanding of WEP is Water Injection into the manifold and not Nitrous. Most engines will get about 20% more power with this.

As for Cooling, your comparing an Air Cooled engine (190) to a Water Cooled engine (P-51). Further, the Pony has an air duct  directly under the wings that opens or closes depending on the current engine temperature.

The P-51 has a much more advanced cooling system, but pays for it in an extra vulnerability. It only takes one good hit to inspire a forced landing sometime soon, while the FW190 and P-47 can take a lot more punishment.

Try comparing the 190 to the Jug or Corsair and see what kind of cooling you get.

As for the Dora I don't know a thing about it.

See ya in the Skies, Mahaps the " 113th Lucky Strikes " Should double as test pilots? Would they name airfields after us if we Augered?

Dan / TBlayde.

[J_A_B]

First, the FW-190D-9 in AH is modeled as though it has MW50.  Note that the AUX tank is unavailable for fuel (you can use it on the A-8), also it performs as though it has MW50.  FYI.

On to my main issue:

What I have to wonder is how long till a 190D take to cool down in AH if you run its WEP for 5 minutes.  

Will it cool down to "normal" temp in 10 minutes?


I haven't tested this, but I suspect the following:

I think WEP modeling in AH is fairly generic, made so that 1 minute of WEP usage requires 2 minutes cooldown time.  Each plane also has a hard limit on WEP use time--5 minutes for most planes, 10 minutes for a few (like the D-9).  

If this is indeed the case, this means that the planes that have the longer WEP time available have the advantage in that they don't need to worry as much about WEP running out in the middle of a fight.  The drawback to doing this is longer cooldown times, but that is well worth it as opposed to not being able to use WEP when you really need it  

Anyway, that is what I suspect.  It might be reight, it might be wrong.


Realistic WEP modeling is undesirable in AH because of the fuel multiplier.  Consider that in a real 190D-9, the MW50 allowed it for 40 minutes total WEP time......but in the AH MA, the D-9 only has 32 minutes flight time on 100% fuel TOTAL...and even less if you use WEP!   And, if you applied fuel multiplier to the MW50, then you'd actually be REDUCING the amount of WEP available to the D-9 from what it already has!

J_A_B

[DingHao2]

Originally posted by TBlayde
The P-51 has a much more advanced cooling system, but pays for it in an extra vulnerability. It only takes one good hit to inspire a forced landing sometime soon, while the FW190 and P-47 can take a lot more punishment.

To begin TBlayde, Hazed is referring to the Fw-190 D-9, which was liquid cooled, like the P-51 (exept with an annular radiator instead of one under the fuselage), and not the Fw-190 A or F models, which were fan-assisted air cooled engines.

Fw-190 F-8 engine can be killed with a single hit inexplicably (and it's air cooled; Fw-190 A-5 and A-8 seems to be pretty vulnerable in the engine oil case, which my research has shown that it was armored.  I know this from my own experiences flying these planes.

Now, as for the P-51D, I have heard reports from some people that it is difficult to get a hit on the radiator from the 6 'oclock position, but I can't verify this; I have hardly ever ran into a 51 before, anyways.

[Wilbus]

John, 190's could override their engines just like the normal WEP on the P51. The MW 50 gave it extra speed, more then normal WEP though and it was run 10 minute then 5 minute cool down.

[hazed-]

Yes basically the 190D9 engine the Jumo 213A-1 liquid cooled 12 cylinder in-line engine is rated at 1,776HP for take off.With MW50 water methanol injection the engine rates 2,240HP.
this is from 'The luftwaffe fighter force: the view from the cockpit' Adolf galland et al edited by david C Isby and all info is taken from 'Air defence of the reich volume 2 the fighter arm (the jagdwaffe) Pamphlet series september 1944'
this is part of a training sect.Nr 1410/44 confidential report for trainees in 44.....

'Another method of raising engine performance is by water-methanol injection.This helps to cool the engine and brings about an incresed performance by greater manifold pressure.Methanol has a favourable influence on anti-knock properties.The increase in power is greatest at low altitudes.It has an increase of about 30 km/hour at all altitudes up to full boost altitudes(where the engine had its best performance).Used in periods of 2-20 minutes.'

so here you have an explanation. What it basically means is the p51 would run his engine at max boost until it overheated where as the water metanol actually PROTECTED the engine from damage while it was used.Also according to this book it ran for 20 minutes so again the dora has half what it had in real life.
I knew this before and have accepted the 10 minutes in AH as a 'representation' of the real times just as im sure the p51d runs at full manifold(wep) for more than 5 minutes right? Lets hope so eh? or we may have uncovered yet another strange discrepency.

So John9001 when you say "so when your dora ran out of "boost fuel ' the P51 would catch you and shoot you down as they did in real life." lets think about it for a second.You run full boost for too long you cause more damage to the engine than the dora would and the dora would STILL have normal wep after the methonol ran out.so the dora could go full boost for something like 20 minutes with methanol while you boost to top temp in half that time in p51 then probably after the water methanol is switched off the dora could then run quite a while without the water methanol and ignore the wear and tear to the engine (if hes chased) whereas your P51 by this time is rattling its pistons and melting! catch them at the end of a fight in your 51 and yes you would run them down but so would a dora that catches your overheated p51 if the situation was reversed

maybe this explains that report by kurt tank about how he opened the throttle on a ta152 and left 2 diving p51s behind? We all suspect its just idle boasting but then again who knows?


anyway back to the subject:

Dora should have 10 mins boost and then cool at the same rate as any other liquid cooled aircraft.The top temp is around 120 to 130 on all planes in AH's simplified wep so they should cool down in the same time. I really cant see any justification so far which explains the present system of 2X the wait for the dora.

[Wilbus]

US pilot report that the P51 and P47 (although different engines) could be run on WE (overboost) for 3-5 minutes depending on how you treated the engine. We obviously have the longer.

[HoHun]

Hi Hazed,

>Yes basically the 190D9 engine the Jumo 213A-1 liquid cooled 12 cylinder in-line engine is rated at 1,776HP for take off.With MW50 water methanol injection the engine rates 2,240HP.

Actually, I don't think the Jumo 213A-1 was able to produce 2240 HP in the Dora. The fastest speeds I've seen are for the ca. 2100 HP rating (curve 3):

http://server3003.freeyellow.com/jagdhund/FW190D-9/D9speedGraphWeb.jpg

It seems like the AH Fw 190D-9 uses either curve 2 or curve 4:

http://www.hitechcreations.com/charts/190d9speed.gif

However, the data for the Focke-Wulf chart shows that the sea level speeds of these curves were achieved with around 1900 HP only:

http://server3003.freeyellow.com/jagdhund/FW190D-9/D9speedWeb_01.jpg

So the AH Fw 190D-9 appears not to be a fully developed, 2100 HP Dora, but an earlier version with just 1900 HP.

Regards,

Henning (HoHun)

[HoHun]

Hi again,

Correct link:

>It seems like the AH Fw 190D-9 uses either curve 2 or curve 4:

http://www.hitechcreations.com/models/190d9.html

Regards,

Henning (HoHun)

[Wilbus]

Hohun, naudet did ALOT of research about the Dora and his conclusions were indeed that we have the 1900 Hp version, meaning that the Dora could very well go faster and climb faster.

[DingHao2]

Sounds like Hitech's got some explainin' to do on why the Dora's porked.

[Naudet]

Wilbus, i never really was sure which version we have.

I am just sure that our D9 uses curve 4 (matches it closest) and so indicates that it should be a D9 using MW50.


Even after a long discussion with Henning, i can not say which one we really have.
Henning says its a 1900PS D9 and he has some exellent arguments.
What is especially interesting is this
http://server3003.freeyellow.com/jagdhund/FW190D-9/D9speedWeb_01.jpg
page.

It shows that with 1925PS 611 km/h IAS were achieved at SL. And as there is no difference at SL between IAS and TAS, if we look at the TAS curves in the speed chart, we will see that 611 km/h exatly match the SL point of curve 2 (Special WEP C3fuel)

And as curve 4 (Special WEP +MW50) is only 600km/h at SL, it must have less than 1925 PS.

So we should have a 1900PS D9, as AH's D9 matches curve 4.


My problem with that is,  that i could not find any evidence that there was a special WEP boost setting using MW50, that gave 1900PS. In all sources and documents i found MW50 WEP is always noted with a power output of 2100-2240 PS.

[Dowding]

I understand that they are different and the figures concerning this issue. But...

Hazed - so you don't actually have any evidence to contradict the current modelling?

There is no reason why the cooling dynamics of the P-51 engine compared to the 190 engine should be the same. Same goes for any other plane in the game.

Clearly HTC has some reason for creating a difference... it's entirely possible they have data that you don't have or have not seen and the difference is entirely justified.

[Wilbus]

there is lots of evidence that the MW50, when used in the Jumo 213 A and E, was run for 10 minutes then cooled for 5 minutes. This was kept up intull the fluid was gone whereafter normal overboosting could be used.

This is indeed proof that the cooling in AH is wrong.