Focke Wulf Ta 152H.

Originally Posted by KraziKanuK

GT,

MW50 is a low to medium (6-7km) altitude boost juice. GM1 is used at altitudes above that of MW50.

Also I have been told, on this board, that the 'boost juices' were only good for climbing and not top speed.

Umm, not quite.

MW50 could be used any time it was needed. Its primary function was to cool the cylinder and prevent detonation.

GM1, i.e. Nitros-Oxide injection, could only be used when load conditions were right. The engine had to be at full throttle, the prop pitch had to be set proprerly, AND IT COULD NOT BE USED W/O MW50 (I read this just recently, I'll post the source if I can locate it).

If you've ever had a vehicle with NO2 injection you understand how carefully it must be used. It must be mixed into the air-fuel mixture in the proper proportions, too much will cause very late burning fuel. You also have to be very careful about over-revving the engine. It is used for hard acceleration (racing) or sustained hill climbing (RV's), but it is not genrally useful for maintaining high speeds. This is not to say it could not be used for such under very specific conditions such as trying to set an air-speed record, but for combat flying it is highly unlikely. The pilot is far too likely to over-rev and blow the engine.

=S=

Lunatic

[KraziKanuK]

MW50 was of no use above the engine's rated altitude since the boost was decreasing.

GM1 was for use above the MW50's use altitude. The 109E-7, iirc, had a restiction that said not to engage GM1 below 6km. I am not at home so can't check.

You had better find that source, for afaik they were not be used together.

Originally Posted by KraziKanuK

MW50 was of no use above the engine's rated altitude since the boost was decreasing.

GM1 was for use above the MW50's use altitude. The 109E-7, iirc, had a restiction that said not to engage GM1 below 6km. I am not at home so can't check.

You had better find that source, for afaik they were not be used together.

When using GM1, the boost does not matter, the engine develops more power and needs more cooling. The whole point of MW50 is to cool the cylinder, which is not normally needed when the boost level drops, but when you add in the Nitros injection you again need the cooling.

I'm sure I'll locate the info again soon. Been reading a lot recently, I have a trove of new docs to study. It may be in the TA-152H manual, which I used translation software to translate what appeared to be interesting sections - if so we should find out as soon as delcyros is done with his translation. I'm hesitant to keep searching until that translation is complete.

=S=

Lunatic

[DerAdlerIstGelandet]

I am not really up to date on this but everything that I have read says that they are not to be used together. The MW50 was for use at lower altitudes and the GM-1 was for use at higher alltitudes.

Here is what it says on a site about the Ta-152:

Engine: Junkers Jumo 213E-1 twelve-cylinder liquid-cooled engine rated at 1750 hp for takeoff (2050 hp with MW 50 boost) and 1320 hp at 32,800 feet (1740 feet with GM 1 boost). Maximum speed: 332 mph at sea level (350 mph with MW 50 boost), 465 mph at 29,530 feet with MW 50 boost, 472 mph at 41,010 feet with GM 1 boost. Service ceiling was 48,550 feet with GM 1 boost. Initial climb rate was 3445 feet/minute with MW 50 boost. Weights were 8642 pounds empty, 10,472 pounds normal loaded, 11,502 pounds maximum. Wingspan 47 feet 41/2 inches, length 35 feet 1 2/3 inches, height 11 feet 0 1/4 inches, wing area 250.8 square feet.
http://www.csd.uwo.ca/~pettypi/elevo...her/ta152.html

Series production orders for the Ta 152C had been placed in October 1944, the delays being a result of the Luftwaffe still continuing to support the Jumo 213 over the DB 603 for the Ta 152 as late as the autumn of 1944. The Ta 152C with the lighter DB 603 engine was otherwise identical to the Ta 152B. It was considered primarily as a Zerstorer. The MW 50 boost installation for the enhancement of low-altitude performance was standard.
http://www.csd.uwo.ca/~pettypi/elevo...her/ta152.html

I used to think so too. But recently I read that GM1 use was prohibited without MW50. Lets wait till delcyros finishes the translation (or you might scan for it ???), it may be in the TA152 manual.

=S=

Lunatic

[DerAdlerIstGelandet]

I will look for it. If it had to be used with the MW50 then it is new to me.

[Erich]

I./JG 3 used the MW 50 boost in high altitude Bf 109G-6/AS in April and May of 44 as well as JG 1. this was to compete with P-51's at over 32,000 feet. Our staffel 10.(N)/JG 300 also flew the same 109G-6/AS with the same two stage supercharger and thinned oil to take on the Mossies of the LSNF attacking by different routes to Berlin in the fall of 1944. MW 50 was definately used at high altitude !

v/r E ~

[DerAdlerIstGelandet]

I thought it was the other way around.

If you think about it, it makes sense. The NO2 allows more fuel to be utilized, providing oxygen in the post flash phase of combustion. The fuel burn from the spark plug flash heats the NO2 and splits the molecule releasing the O2 to allow unburned fuel to burn. More fuel burning means more heat in the cylinder, which means there is a need for additional cooling, which is the primary function of the MW50.

=S=

Lunatic

[DerAdlerIstGelandet]

Yeah sounds right.

[KraziKanuK]

Erich, what was the rated altitude of the AS engine?


RG, pg 71 of the Harmann 152 book does not mention any use of the 2 together. Specifically saying, MW50 below the engine's rated altitude and GM1 above the engine's rated altitude (max boost altitude).

MW50, or as the Allies called it ADI, cooled the intake charge which stopped pre-ignition thus keeping the combustion chamber temp down.

Where did the GM1 go in the 109, for the MW tank was behind the pilot?

Originally Posted by KraziKanuK

Erich, what was the rated altitude of the AS engine?


RG, pg 71 of the Harmann 152 book does not mention any use of the 2 together. Specifically saying, MW50 below the engine's rated altitude and GM1 above the engine's rated altitude (max boost altitude).

MW50, or as the Allies called it ADI, cooled the intake charge which stopped pre-ignition thus keeping the combustion chamber temp down.

Where did the GM1 go in the 109, for the MW tank was behind the pilot?

I've seen that statment too. I'll have to find the info. I know I saw it, but I seem to have failed to create a link to it with a special name so I can find it. Like I said above, I have lots of docs I've been investigating recently (the TA manual is one example), so it's hard to remember exactly where I saw it. I was surprised when I saw that GM1 needed MW50 to be used, but I know that's what it said.

As for the NO2 tank, I'm not sure where it went on the K, but it's a relatively small tank so it could go lots of places. Typically NO2 injection occures after the air and fuel are mixed, at the top of the intake manifold.

=S=

Lunatic

[KraziKanuK]

I think you, or whomever made the statement, read it wrong. NO2 also acted as an anti-detonant. It was in a liquid form until released into the intake. In the G-6, a full GM system weighed 434lb. The fill point was the same for MW and GM.

Maybe the 109 expert, Dalton, will enlighten us?

[Erich]

The G-6/AS did not have both though just to make it clear. Not sure what the engine ceiling height was but in the case of nf operations always the 109 was in hot pursuit of the Mossies by diving on them so they did have an altitude advantage on operations.

to tell you the truth I have not heard that the Ta 152H had the GM-1 boost system installed only the MW 50

E

Originally Posted by KraziKanuK

I think you, or whomever made the statement, read it wrong. NO2 also acted as an anti-detonant. It was in a liquid form until released into the intake. In the G-6, a full GM system weighed 434lb. The fill point was the same for MW and GM.

Maybe the 109 expert, Dalton, will enlighten us?

Nitrous does provide some cooling and anti-knock benifits, but it is easy to see how this would not be enough since it was taking the engine back up over the normal power levels. Also, radiators are inefficient at high altitude as there is very little air flowing through them relative to the power outputs involved.

I seriously doubt the MW50 and GM1 used the same "fill point", as normally water is injected into the airstream either with the fuel or before the fuel, where NO2 is injected after the air. But it is possible, there would be no reason the two could not be mixed and use the same hole.

PS: I'm pretty sure the source is a Luftwaffe or Messershmitt document. I have a bunch of them, but unfortunately you cannot search on images of documents, which makes finding this specific info... difficult.

=S=

Lunatic