Aces High Bulletin Board
General Forums => Aircraft and Vehicles => Topic started by: MiloMorai on July 07, 2005, 02:30:27 PM
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Before you get your knickers bunched in a knot you know where Barbi, I ask because I am trying to defend your uber 109.:eek:
Early 109s, afaik, were limited to 2 minutes and then later to 10 minutes. What is being said that 2 minutes was always. It is also being said that it was restricted to climb only. No level speed usage.
So 109 expert Barbi, give me some ammo to debunk and put the record straight.
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It`s 10 minutes continous use time at one time, then ca. 5 min to be allowed for cooldown. All MW50 models.
The DB 605A`s max coolant temperature of 115 celsius was also allowed for 10 minutes at a time, 105 celsius was allowed continous. I guess the 605D`s limit was 120, as the cocpit`s temp gauge was marked at that regime.
From the 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."
Which translates to :
"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."
As for not allowed to be used in level speeds, well that`s strange, why there are countless german max speed curves with MW50, GLC charts ? And no instruction not to use it under specific conditions?
The only kind of restriction that woud appear in use during max level speed flight is the opening of radiators when heat increased, unless they were overidden manually. This would allow for much greater cooling capacity, but the drag penalty is great. True for all kind of WEPs and liquid engined fighters, though.
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Originally posted by Kurfürst
From the 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."
How is 'geringer motorleistung' specified in terms of revs/boost levels/coolant temperture etc. ? Max continuous cruise? Just curious you understand. Could it indeed be influenced by opening radiator flaps allowing more cooling (and more drag?)
How is this implemented for 'our' Bf-109G6 and G-10? Is WEP implemented as being MW-50? I've seen a ton of threads discussing this but frankly I don't know. I am aware of the zillions of mods available for the 109, but I do not know how the AH version is modelled in this regard.
I never even used all the WEP time when flying a 109 in AH in one go, so I never checked cooling time either. I would expect it to be 20min in AH, not 5 (2min cooling for 1 min WEP). AFAIK only the Ki-84 has this reversed (1min WEP, 30s cooling). Correct me if I'm wrong.
Another thought: 10min WEP, 20 min 100%, 10 min WEP, wouldn't even be possible I guess with the 109's fuel load in AH.
And another issue: How do the climb rates of the AH2 F4U's and the 109-G6 compare at let's say 15k? I would expect the 109 to leave any F4U far behind, save for the F4U-4. I had trouble shaking one by outclimbing the other day. Could have been an F4U-4 though but my ISP discoed me before he came close enough to see it :(
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The G-6 didn't have MW-50 (rl or in AH).
I don't think Kurfürst or MiloMorai play AH.
As for 'WEP' in AH its not based on reality for any plane. The way it works in AH is the plane runs at 'WEP', engine temperature goes up limiting the time of 'WEP' (it is different for the various planes) then automatically shuts off. Then after a given 'cool down' period (again varies with the plane) 'WEP' can be used again. You can repeat this indefinitely.
In real life the G-10 would be limited to around 26 min of MW-50 at a max of 10 min with a 5 min cool down.
In AH the time limit for 'WEP' and the cool down period vary with the aircraft.
'WEP' is also a rather generic term as used in AH.
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Originally posted by Wotan
The G-6 didn't have MW-50 (rl or in AH).
I don't think Kurfürst or MiloMorai play AH.
As for 'WEP' in AH its not based on reality for any plane. The way it works in AH is the plane runs at 'WEP', engine temperature goes up limiting the time of 'WEP' (it is different for the various planes) then automatically shuts off. Then after a given 'cool down' period (again varies with the plane) 'WEP' can be used again. You can repeat this indefinitely.
In real life the G-10 would be limited to around 26 min of MW-50 at a max of 10 min with a 5 min cool down.
In AH the time limit for 'WEP' and the cool down period vary with the aircraft.
'WEP' is also a rather generic term as used in AH.
Thanks for the answer Wotan. The use irl for the G-10 was clear from Kurfürst's info, but I didn't know that the G-6 never had MW-50. After all, WEP times for the G-6 and G-10 in AH are the same so I expected similar systems.
I always thought that 'WEP' in AH2 was in some ways related to how it worked irl, like water injection for P&W's, MW-50 etc. for LW birds. Especially the arrival of the Ki-84, with it's odd WEP function made me think this.
People discuss fuels and engine settings here all the time (think about the +12lbs issue on the Spit I, or the settings for the D-9).
Makes me wonder why the old AW system (not that I ever played it) of reduced fuel quality = reduced performance was never implemented to some degree here. Knock out a few refineries and influence plane performance, disabling WEP or breaking the engine when you run it at WEP settings.
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Fyi,
generally G-6 + MW-50 = G-14
HTC tried to implement some level of engine management with the increased fuel burn multiplier and re-did most of the planes with the correct power settings and fuel consumption.
However, this only really effects those planes with small fuel capacity to begin with. Ami planes still run at 100% power all the time and take less then 100% fuel. They have done nothing to address the unlimited 'WEP' or the 'run at full throttle all the the time' beyond that.
To be fair though most engine / power limitations that were set by the various countries were not set so much because engine will 'blow up' or fail but to keep aircraft in service. When engines are run at max power for pro-longed periods this will increase the time between overhauls / maintenance.
I am not so sure about 'reduced fuel quality' because it would be too subjective. It would just be another 'made up' fix.
In AH there's no real concern about 'service life' of the engines, we just get a brand new plane each re-spawn. The question becomes what should be done (if anything) to create a more real flight profile (cruise, climb & combat etc).
In some games like FB/AEP/PF the artificial solution is to have engines overheat so that you are forced at times to run at less then 100 / 110% power.
However, for AH planes that use water (ADI / MW-50 etc...) to increase boost certainly should have a limit. Like fuel there wasn't an endless supply of water, it ran out.
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As a general rule G-5s and G-6s did not have MW 50. Otoh, many were converted to use it in early 1944. This was possible as there were quite a few GM-1 using G-6s produced (G-6/U2), and these already had the neccesary installations requiring only minimal changes.
Butch mentied some time ago that in May 1944 250 G-6/U2 were converted into MW50 using G-6s, and there are anecdotal evidence from Heinz Knoke using the stuff in April 1944.
However in July the G-14 production started, and it was basically a standardized G-6 with MW50 installed as standard in the factory.
For all practical purposes, an in-game G-14 should represent G-14s and all G-6s with MW, while the in-game G-6s those aircraft that were around in 1943 w/o the booster.
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What would the performance gain of MW-50 be for our G-6? Near G-10 standards? Seems likely as it shouldn't be that hard to include a G-14 for HTC.
I know this has been discussed before (at length :( ) but I don't want to dig up old posts.
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The G-14 basically has the same engine as the G-6 (DB 605A) except with the addition of MW-50. (G-14 = DB 605AM). MW-50 would provide a performance boost above the current G-6 but only below FTH. Which considering the low alt combat of most of the furballs in AH the G-14 would fit right in.
The G-6 that is in AH is a later G-6 with the improved canopy and larger tail.
The G-10 has a DB 605D with a larger supercharger (from DB 603). The Large supercharger allows better performance at higher altitudes (higher FTh then the DB 605A).
Pyro has said that the G-10 in AH is really a K-4 but with the option of 2cm instead of just the 3cm. AH doesn't really have a G-10.
A G6/AS (DB 605AS) has a DB 603 supercharger as well.
A G-14/AS (DB 605ASM) would include MW-50.
Performance wise the addition of a G-14 into AH would give better speed then the current G-6 at emergency power below FTH.
It would not have the performance of the AH G-10 and performance would be about the same as the current G-6 above 5700m (? IIRC).
Personally I like to see HT do a real G-10 and K-4 (split the hybrid they have now) and add a G-14.
The AS (either G-6/AS or preferrably the G-14/AS) would be nice but that's probrably asking to much (well asking for G-14 is probrably in vain as well but WTH).
One would think with ToD OTW that HTC woul dbe somewhat focussed on filling the gaps in the planse set. With the release of the newer aircraft this doesn't seem to be the case.
However if I were GOD/DOG I would do as follows:
add a 109E-7
Keep the current G-6
Add the G-14
Real G-10 (maybe small perk)
K-4 perked
This would give AH
109E-4
109E-7
109G-2
109G-6(late)
109G-14
109G-10
109K-4
ToD could make do from there for the time being.
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Nice Wotan, was about to ask what the optimal 109 lineup would look like.
Oh, hijack warning:
109E-4 counter with Spit Ia, cs 100 oct ;)
109E-7 Spit II
109G-2 Spit IX LF
109G-6(late) Spit VIII
109G-14 Spit IX merlin 66/70 clipped
109G-10 Spit XIV
109K-4 ,,,,emmm still thinking.
Well, sorry, just couldn't resist. :D
Anyway, a G-14 in Hartmann's colours would be utterly cool for AH!
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The G-14 basically has the same engine...
A G14 is basically the G series w DB605A engine upgraded to a standar. Officialy laters G6 w MW50 where renamed to G14 ( w some additions), the problem is that you can found a lot of mix of set up.
Btw, and regarding MW boost time:
It`s 10 minutes continous use time at one time, then ca. 5 min to be allowed for cooldown. All MW50 models
What about MW30?, i know it was used too. Lack of enough boost liquid.
This bring me a question, the cooling effect seem less to me as im gessing. This will bring differents heating times? i mean, less cooling effect, less time on "WEP".
regards
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Good info, but you forget the nicest 109, the F series ;)
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Mw 50 better than GM 1? Galland said the GM 1 stuff would evaporate in summer.
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Mw 50 better than GM 1?
GM-1 and MW-50 aren't the same thing.
GM-1 could only be used above 7500m (? IIRC).
MW-50 only provided increase boost below FTH.
Above FTH the SC is already losing power .
hogenbor,
Yup I forgot the F-4
Orka,
Hello Orka!!!!
Its been a while. How are you?
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I know they aren't the same thing. that's why I asked which is better.
MW 50 cools engine, & perhaps weighs less?
Which provides more power & is less problematic?
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Its not an either or question.
GM-1 was to provide more power at higher altitudes (above 7000m or so).
It wasn't widely used in service. Although some 109 variants (109E-7z etc...) were designed with GM-1 in mind.
MW-50 was simply injecting water into the eye of the SC to cool the charge. The cooler the charge the less risk there is of detonation and thus the engine can be run at higher boost below FTH. Above that (5,500m or so for most LW planes) MW-50 isn't needed because the SC is already losing power.
MW-50 and GM-1 are completely different not only in 'what they are' but what they were 'used for'. A comparison question of 'which is better' makes no sense.
With the introduction of the AS engines and DB 605D (which meant a larger supercharger) providing better performance and extending FTH GM-1 wasn't need for the late war 109s.
GM-1 = high alt performance
MW-50 = higher boost below FTH.
For example the Ta-152H had both MW-50 and GM-1.
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The reason I asked an either or question was because GM1 appeared earlier, then MW 50 seemed to replace it as it appeared after.
Thanks for explanation though. Both do provide extra power, so they are similiar engine adds.
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They're not similar.... GM1 provided oxygen at altitudes where supercharger couldn't (above FTH) , and MW50 was a antidetonant/refrigerant so you could raise the manifold pressure using the supercharger (below FTH)
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So, one for high-up, and one for low-down?
Clever.
But some weight penalty?
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They were similiar in that they provided extra power. Yes they did it at different altitudes, understood, but still extra power is extra power.
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The power boost GM-1 prodived was scary : + 300 HP at above 1500m of the full throttle height...
Ie. the standard DB 605A-1 had 750-790 PS output at 10000m. GM-1 would boost it to 1000-1100 PS at 10 000meter altitude... and the speed is boosted by 120 kph... to well over 700... :eek:
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They were similiar in that they provided extra power.
MW-50 didn't provide 'extra power' it simply cooled the charge. Any extra power was the result of being able to run at higher boost with out the fuel detonating pre-maturely.
GM-1:
I will quote Hohun from a previous post:
GM-1 was the German WW2 code-name for N2O (nitrous oxide, or laughing gas).
N2O can be added to the fuel-air mixture of an internal combustion engine. In the compression cycle, it's broken up into its components, releasing oxygen that can be used for combustion.
As the challenge of high-altitude flight mainly consists of getting enough oxygen into the cylinder to maintain adequate power - which due to the decreasing air density becomes more and more difficult at altitude - N2O equates to extra power.
In fact, N2O was injected into the supercharger in liquid form through small jets, and each jet gave a constant power boost when employed. Depending on the type, you might have a 120 HP jet and a 240 HP jet, which of course added 360 HP when used in combination.
That's the resason N2O was available in steps - you couldn't add 360 HP to an engine that was already running at close to full power, or the resulting forces would destroy vital parts of the engine.
This is the main reason N2O was preferred over pure oxygen, which could be (and experimentall, was) used for the same purpose - it just gave too much power.
The nitrogen share of the nitrous oxide has a benefit, too, since it absorbs some energy on being broken up in the cylinder, controlling the detonation and allowing higher pressure.
Since N2O is injected into the supercharger as a liquid, it also gives a charge cooling effect on evaporation (cooler air means more oxygen in the same volume).
Initially, N2O was stored under high pressure to keep it liquid (laughing gas, after all, is a gas under standard conditions), but that meant the N2O vessels blew up like a bomb on being hit, so from 1941/42 on it was stored at very low temperature in an insulated tank that kept the content at less than -90 °C for as long as the sortie lasted.
(It was used by bombers like the Ju 88 and by reconnaissance planes like the Ju 86 as well, so that could be quite a long time. For fighters at readiness on the ground in the hot summer sun, though, the insulation would not have sufficed and the N2O would have begun to boil out through the safety valve after a while.)
For comparison: 0.1 kg/s of N2O injection gave extra 300 - 400 HP, virtually out of nothing.
The only drawbacks were the weight of the system (which also included compressed air bottles to force the N2O out of the insulated tank), and - more importantly - the high rate of consumption. If 0.1 kg/s gave 350 HP, that made for a specific fuel consumption of 1000 g/HPh, which compares very unfavourably to the DB601A's normal 220 g/HPh at high power :-)
So, N2O was bad for range, but great for high-altitude power.
Oh, by the way, someone mentioned that N2O was to be used for short bursts only. According to what I have read, it could be used as long as it was available and in fact short bursts were to be avoided as filling and emptying the N2O lines took some time and created some engine management difficulties.
Regards,
Henning (HoHun)
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So the plane went "faster" when MW 50 was applied, hence more power.
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That's not how it works.
With the GM-1 N2O released O2 and the O2 was 'burnt'. This additional oxygen at high altitude allowed for more power.
MW-50 was a 50/50 water-methanol mix that didn't burn it just cooled the charge. You get more power because you run the engine at a higher ATA. (move the throttle all the way up).
MW-50 was 'turned-on' by a switch on the dash. It was then injected only when the throttle was pushed up all the way to stop. Pull back the throttle injection stopped.
You can't compare the two as if one would be better then the other, they were used for different things, operated differently etc...
You may keep this circular line of discussion going if you like but your question was answered.
Your original question was:
Mw 50 better than GM 1?
With your on-going words games you look like some one who is trying to avoid being wrong.
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So, one is the nuke, and the other one keeps it from cooking the engine?
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Meyer dixit, thats how it works. :
GM1 provided oxygen at altitudes where supercharger couldn't (above FTH) , and MW50 was a antidetonant/refrigerant so you could raise the manifold pressure using the supercharger (below FTH)
GM1 not mean rise engine power, that engine only can run at max MP, just raise FTH. So you have an engine runnig at max power@higher alt.
MW50 provide cooling effect, just rise MP. So you have an engine running above max power w/o cooking.
@Wotan
Im still alive, i think S!
regards
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No word games really. I was attempting to find out which of these 2 devices was better, hence more efficient, less problematic, easier to work on, weighed the least, & last but not least - which one did the job of making the plane go faster "better".
& I'm not wrong when I say both of these devices did the same job, ( albeit at different altitudes ), which is- make the plane go faster. Now if a plane goes faster, technically speaking more power has been obtained.
Different methods are employed by these devices to achieve this goal which is very interesting & I appreciate explanations. But the Germans, ( on single engined fighters ), used GM1 early, then seemed to favor MW 50 boost, (152 being an exception employing both), which may well be a hint that mw 50 was prefferred, my speculation. & that's why I asked.
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Using GM-1 was an hassle, the product being highly volatile you could not fill the tank and just wait a few days before using it.
Moreover it lost most of it's interest when the engine being produced reached FTH in the 7-8km range, indeed GM-1 could not really be used below FTH+1500/2000m meaning that you had to fly at 9000-10000m to use it.
At such an altitude you most likely need a pressurised cockpit and it's very unlikely you'll encounter anyone except for some recce a/c.
G-5/U2 and G-5/U2/AS were kept with GM-1 just for such business, intercepting high flying mossies and the likes.
Most usefull was the MW-50 boost which permitted higher outputs for a long time at usual combat altitude.
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Thankyou Butch.