B-29's versus Luftwaffe

[davparlr]

Isn't that like saying "George got killed and eaten by a black bear, but if it had been a grizzly he would have realized how deadly it was and fought it off."?

A very astute comment!

 

[Soren]

davparlr,

The Me-262 is a far superior a/c to the P-80. The Me-262 is faster, turns better climbs quicker than the P-80. So if both pilots are equally trained then the Me-262 will come out on top. Ofcourse by late 44 the average Allied pilot was much better trained than the average Luftwaffe pilot, there we agree.

As for the Jumo 213EB engine, it weighed 940 kg, it was to run on C3 fuel and be equipped with MW50 GM-1 boosting systems. The max output was 2,500 PS at rated altitude, and it was planned to be boosted further to 3,000 PS.

The things you suggest occurring would have had to start happening in '43, not April '44 to be effective. By this time the infrastructure of Germany was already crumbling and fighter sweeps were beginning to occur. After D-Day, short range for air strikes would make German defenses miserable. It didn't matter what technology was fielded, it had to be supported and the means to do this was quickly deteriorating.

It had to occur in the beginning of 1944 at the latest, I agree.

 

[Messy1]

I have a question. Back through this thread there are some people stating more or less that the B29 would have been shot down in droves because Hitler would have seen how dangerous the B29 was and developed all these weapons to counteract it like- producing the Me262 as a fighter, developing the Ta152 long before they did, and someone even said developing the SAM(!)missile to shoot it down.

Isn't that like saying "George got killed and eaten by a black bear, but if it had been a grizzly he would have realized how deadly it was and fought it off."?

Less face it, by the middle stages of the war, all Hitler's dogs weren't barking, at least not all together, and he wasn't making the best of decisions. None of his peons were willing to tell him he was wrong so what would really have changed except that a faster higher flying aircraft, carrying more bombs and computer controlled defensive guns was now killing his people?

It wouldn't matter if the P51 and P47 couldn't fight well at 30,000 ft. They would simply patrol in front of and below the B29 and intercept the Germans before they could get up to the B29's altitude.

One more thing, those of you that think the Me262 was the answer to the 30,000 ft B29 question need to study the Me262 alittle better. It didn't do well at extreme altitudes, it had alot of engine trouble up really high. It actually performed better around 25,000 feet or lower.

This is similar to what I was trying to say a few posts back. Agree 100%.

 

[Colin1]

...someone even said developing the SAM(!) missile to shoot it down...

Yes indeed
the Enzian being one such example.
It would have employed an infra-red guidance system too. However, by that late stage, the rapidly disintegrating organisational state of Germany and project prioritisation elsewhere saw the program cancelled in mid-January 1945.

Didn't quite get there but the Germans were knocking on the door of SAM interception.

 

[red admiral]

Didn't quite get there but the Germans were knocking on the door of SAM interception.

The UK was in a similar position with a variety of SAM (or rather GAP, Guided Anti-Aircraft Projectile) projects being built and tested. Their problem was rather more complicated than the German's though; an individual bomber, probably flying at night, is more challenging to hit than a 1000x1000x1000yd box of B-17s.

 

[Erich]

there is documentation of at least 50 ground to air rockets being fired at US heavies in 45...............and I know you all will ask this but will have dig for the info as it is probably in the pit of doom at present, the figure just stuck out to me at the moment.

no matter nothing was going to stop the US heavy armada except for the hand of God, the LW was not or ever ready even by late 44 to counter what was beset before her. She did her best with what she had but it was failed attempt, the Reich defense Jg histories speak of it continually

 

[HoHun]

Hi Messy,

>To me it is a forgone conclusion. If they could not cope effectively with the older, slower bombers, how in hell could they cope with the addition of the B29 to the bomber force in ETO.

If you look at post #1 in this thread, the question was actually "What would the luftwaffe have to do to defend the Reich if they had to combat 8th airforce Superfortresses instead of B-17's and Liberators?"

You are answering the question: "Could the Luftwaffe have achieved total air superiority over the Reich if ..." - they obviously could not, but that was not what Ralphwiggum originally asked for.

Regards,

Henning (HoHun)

 

[Messy1]

Hohun, I did get off topic a little I see, but my opinion does not change too much.

 

[HoHun]

Hi Messy,

>my opinion does not change too much.

Wow - elegant and modest ambiguity

Regards,

Henning (HoHun)

 

[Messy1]

That is what happens when you read through several pages of posts, and then post an answer without first re-reading the question one last time.

What I should have said was although I was off topic, my overall opinion is still the same, minus the B17's and B24's of course.

 

[TheMustangRider]

there is documentation of at least 50 ground to air rockets being fired at US heavies in 45...............and I know you all will ask this but will have dig for the info as it is probably in the pit of doom at present, the figure just stuck out to me at the moment.

no matter nothing was going to stop the US heavy armada except for the hand of God, the LW was not or ever ready even by late 44 to counter what was beset before her. She did her best with what she had but it was failed attempt, the Reich defense Jg histories speak of it continually

I totally agree with you Erich, The Germans had the technology but didn't have the resources. By 1944, once the allies had the solid ground in Europe and the Russians were advancing in the east, Germany was finished.

 

[Glider]

Erich
Have you any idea how many of those ground to air rockets hit?

 

[davparlr]

The Me-262 is a far superior a/c to the P-80. The Me-262 is faster, turns better climbs quicker than the P-80. So if both pilots are equally trained then the Me-262 will come out on top. Ofcourse by late 44 the average Allied pilot was much better trained than the average Luftwaffe pilot, there we agree.

I doubt you have any supportable evidence of the statement that it superior to the P-80, much less far superior. I do not think there is much comparison data available and what there is does not have well documented descriptions of test procedures. I would be surprised if this documentation did not exist somewhere in archives of the AF, and, maybe someday someone will uncover this info. Until this documentation, if existing, is found, you statement is unsupportable. Performance data that is available indicates that the P-80A is as fast or faster, has better power to weight ratio, equal to or better climb, and much better ceiling.

As for the Jumo 213EB engine, it weighed 940 kg,

Don't forget the cooling system and coolant. Gotta cool it to run it.

it was to run on C3 fuel and be equipped with MW50 GM-1 boosting systems. The max output was 2,500 PS at rated altitude,

Unless its critical altitude is much different than the E1 (around 15k ft.?), and it behaves like the E1, it will be nowhere near 2145 hp at 33k ft (10 km).

and it was planned to be boosted further to 3,000 PS.

This is worthless unless we know what was planned for the PW2800. I believe it was reported on this forum somewhere that the PW2800 was tested at 3500 hp for quite a while with no damage. The P-47M had a critical altitude of 38,750 ft (11.8 km) at 2100 hp without nitrous, at this altitude, the E1 makes 960 hp without GM-1, 1040 hp with GM-1, 1140 hp less and 1060 hp less respectively. The maximum power of the E-1, with GM-1, was at 36,100ft (11 km) making 1200 hp. That's an unbelievable amount of hp to make up by the EB. I think that it is apparent that the PW2800 had excellent high altitude performance potential, even better than the EB.

I did read about the development of a Jumo 213T with a turbo that could possibly even things up.

 

[delcyros]

Turbocharging is not necessarely an efficiant instrument to augment performance at high altitude and high speed, altough it appearently worked very well in the RW-2800.
The Jumo-213E at critical altitude developed 200 Kp of exhoust jet thrust.
That´s quite a lot when You consider that the Jumo-004D was producing a mere 380 Kp thrust at this altitude when running at 100% load.
This equates to 200kg or 2000N which at a speed of 200m/s(440mph) from Power = force x velocity = 400kW at the shaft.
Factoring in the propellor inefficiencies at high altitudes this equates to the aequivalent of ~500kW or ca. 670 hp more power developed by the engine in the first place.
Second order maybe but still to substantial to be ignored.
As you know, to get a 10% increase in speed requires approximtely a cubed increase in power whereas it requires only a squared increase in thrust! It does not come in with increased cooling requirements, too (which would add drag in return)! So it´s maybe not worth to waste that source of power to drive a turbocharger, that´s at least the reason why Rolls Royce invested so much in turbocharging. They tried to find a solution to keep the jet exhoust thrust.

 

[davparlr]

Turbocharging is not necessarely an efficiant instrument to augment performance at high altitude and high speed, altough it appearently worked very well in the RW-2800.
The Jumo-213E at critical altitude developed 200 Kp of exhoust jet thrust.
That´s quite a lot when You consider that the Jumo-004D was producing a mere 380 Kp thrust at this altitude when running at 100% load.
This equates to 200kg or 2000N which at a speed of 200m/s(440mph) from Power = force x velocity = 400kW at the shaft.
Factoring in the propellor inefficiencies at high altitudes this equates to the aequivalent of ~500kW or ca. 670 hp more power developed by the engine in the first place.
Second order maybe but still to substantial to be ignored.
As you know, to get a 10% increase in speed requires approximtely a cubed increase in power whereas it requires only a squared increase in thrust! It does not come in with increased cooling requirements, too (which would add drag in return)! So it´s maybe not worth to waste that source of power to drive a turbocharger, that´s at least the reason why Rolls Royce invested so much in turbocharging. They tried to find a solution to keep the jet exhoust thrust.

All valid points and something I am sure every aero engineer traded off to try to get the best all-around solution for the designed performance envelop.
I have avoided the "Can I design a better aircraft thread" because I think that Messerschmitt, Tank, Johnson, et.al. were tops in their field and made all the tradeoffs of available technology to arrive at the solution of their particular requirements. I would never think I could do better, even with hindsight.

 

[red admiral]

Some figures from RR for a Spitfire Mk XIV with and without ejector exhausts. Adds about 50mph at high altitude.

Super-chargergear Altitude(ft)Withoutexhaustthrust-Withexhaustthrust

MS 5,000 345 351
13,500FTH 388 400
23,500 373 399
FS
31,500FTH 419 454
40,000 377 424

 

[Soren]

I doubt you have any supportable evidence of the statement that it superior to the P-80, much less far superior. I do not think there is much comparison data available and what there is does not have well documented descriptions of test procedures. I would be surprised if this documentation did not exist somewhere in archives of the AF, and, maybe someday someone will uncover this info. Until this documentation, if existing, is found, you statement is unsupportable. Performance data that is available indicates that the P-80A is as fast or faster, has better power to weight ratio, equal to or better climb, and much better ceiling.

I disagree. Available data contradicts what you are saying.

Don't forget the cooling system and coolant. Gotta cool it to run it.

I think it's around 125 to 150 kg.

This is worthless unless we know what was planned for the PW2800. I believe it was reported on this forum somewhere that the PW2800 was tested at 3500 hp for quite a while with no damage. The P-47M had a critical altitude of 38,750 ft (11.8 km) at 2100 hp without nitrous, at this altitude, the E1 makes 960 hp without GM-1, 1040 hp with GM-1, 1140 hp less and 1060 hp less respectively. The maximum power of the E-1, with GM-1, was at 36,100ft (11 km) making 1200 hp. That's an unbelievable amount of hp to make up by the EB. I think that it is apparent that the PW2800 had excellent high altitude performance potential, even better than the EB.

Oh I disagree, I think the 213EB engine has the same or more potential in this area.

 

[SoD Stitch]

I disagree. Available data contradicts what you are saying.

I don't want to retype the whole bloody quote, but go here to read more about the Wright Field comparison tests between the Me 262 the -80:

http://www.ww2aircraft.net/forum/polls/me262-vs-p-80-a-562-19.html#post442670

 

[davparlr]

I disagree. Available data contradicts what you are saying.

I think available data is contradictory and mostly anecdotal and until some flight test data from the P-80 and Me-262 are available, this discussion can go on ad infinitum.

I think it's around 125 to 150 kg.

Quite reasonable. I made a guess based on similar US aircraft.

Oh I disagree, I think the 213EB engine has the same or more potential in this area.

I won't say that your statement is unreasonable. German engineers were certainly capable of engines of great performance. It just seems like a huge upgrade to the E1. I suspect the performace data on this engine must be lost. I do believe the PW2800 had very good high altitude potenial. The P-47M could generate 2100 hp at 38,750 ft (11.8 km) without nitrous. With nitrous, using the same profile as the E1, it is reasonable for the PW2800 to generate this same power, plus-or-minus 100 hp up to 46,000 ft, 1000 hp more than the E1 could do (roughly twice the power).

 

[Civettone]

Erich
Have you any idea how many of those ground to air rockets hit?

Perhaps Erich's sources are referring to "operational testing".

Kris