Messerschmitt 109 - myths and facts - article now out

[Grendel]

Originally posted by pasoleati

The article has other hilarious gems as well. For example, the author (Mikkolainen) claims with a straight face that German and Finnish pilots had more muscle power than Allied pilots! And he is to be taken seriously?
[/B]

Oh, does it?


-  So why the Allied test pilots have so different opinion? Simple. They were not used to the plane.

- ... they were perhaps partly compensated by the emphasis put on physical exercise in the Luftwaffe and FinAF. Numerous accounts by pilots of those forces mention the amount of exercise and sports conducted by the aircrew. Given that every flight was practically a work out session, the Me 109 pilots flying it regularly were markedly more adapted to its requirements than a pilot who was only flying limited number of test sorties.


Please don't twist what has been written in the article. Besides, that was not written by Markus.

And yes, I stand by my theory. I've discussed with IRL Bf 109 pilots about their lives overall, and debated about this theory with fellow aviation enthusiasts, and the more we've discussed about the theory the more assured I've became about its validity. If somebody explains it in more believable way I'm ready to change my opinion, but so far this theory seems to hold water. I wouldn't go hand wrestle with somebody doing heavy physical work, if I'm a "white collar" worker myself and not adapted to my competitor's field.

Besides, as you can see yourself, the article is primarily about the pilot quotes, and it is not related to Kurfurst's article. This is primarily about anecdotes, Kurfurst is all technical. I tought that is obvious? I must say that I'm pretty satisfied, if a critical reader only found two nitpicks in the secondary content of the article, making up some 0,01 % of the wholeness.

[Kurfürst]

I think it`s a very nice collection and serves the purpose of mythbusting well.. after all people who dislike the 109 usually operate with a few anecdotal evidence - now this collection has TONs of first hand account of what the REAL 109 pilots thought. It`s really hard to claim the messer was a complete cr@p with all these overwhelming amount of opionion of serious men being there. I`ll certainly list the URL for it later on, if that`s ok.

"What ever Gersdorff may say, turbocharging is far more efficient than mechanical supercharger plus exhaust thrust. "

Yes for thrust, but there is a HUGE cost in drag and weight. Just look at the P-47 and P-38. All those expensive airframes, giant turbos, was performance any better than simple mechanical s/c fighters? No. Turbocharging is a very advanced method, it just doesnt pay out for fighters.

[HoHun]

Hi Pasolati,

>The article has other hilarious gems as well.

Hm, I seem to have missed that article. Could you please re-post the link? :-)

>What ever Gersdorff may say, turbocharging is far more efficient than mechanical supercharger plus exhaust thrust.

Von Gersdorff quotes the DVL studies by von der Nüll, including a diagram comparing turbo-supercharged and jet-exhaust equipped engines in motive power and fuel consumption at 6 km and 12 km altitude.

At 6 km, the turbo-supercharger is more effective at about 400 km/h TAS and slower, and more efficient at at speeds up to 500 - 600 km/h TAS.

At 12 km, the turbo-supercharger is more efficient at any speed, and more effective at speeds up to 900 km/h TAS at least :-)

According to von Gersdorff, the main reason why German manufacturers didn't come up with a series production turbo-supercharger was the problem of creating high-temperature, high-speed turbines with the materials available to war-time Germany.

Additionally, most German engineers who had specialized in turbine development were employed in jet engine development, leaving turbo-supercharger development a bit under-staffed. (Insufficient engineering capacity was a major problem in all branches of the German aviation industry.)

>It is interesting to note that the advocates of the exhaust thust theory usually come from countries and manufacturers who failed to develop workable turbochargers.

Well, the contribution of exhaust thrust to total motive power often is forgotten (or at least underestimated), but the German aviation industry definitely appreciated the advantages of the turbo-supercharger - BMW, Daimler-Benz and Hirth-DVL were seriously trying to get them into series production.

(Junkers actually had them in production, but only for the Jumo 205/207 Diesel engines which were running with a relatively cool exhaust so the materials weren't a serious problem.)

Regards,

Henning (HoHun)

[pasoleati]

Originally posted by Kurfürst
I think it`s a very nice collection and serves the purpose of mythbusting well.. after all people who dislike the 109 usually operate with a few anecdotal evidence - now this collection has TONs of first hand account of what the REAL 109 pilots thought. It`s really hard to claim the messer was a complete cr@p with all these overwhelming amount of opionion of serious men being there. I`ll certainly list the URL for it later on, if that`s ok.

"What ever Gersdorff may say, turbocharging is far more efficient than mechanical supercharger plus exhaust thrust. "

Yes for thrust, but there is a HUGE cost in drag and weight. Just look at the P-47 and P-38. All those expensive airframes, giant turbos, was performance any better than simple mechanical s/c fighters? No. Turbocharging is a very advanced method, it just doesnt pay out for fighters.

Kurfurst, do me a favor. Compare wing area/installed power and you will see the 109 wasn´t so superior in aerodynamics.

We don´t really have a valid comparison here as comparing a short range aircraft (little fuel needed) with long range aircraft (plenty of fuel needed) is not valid. For example, the original turbocharger installation in the XP-39 was very compact.

What is more, none of the series produced aircraft with turbos had pure turbocharging, i.e. without mechanical stage.

And, the best mechanical superchargers (i.e. those two-stage designs fitted to the R-2800 and capable of the highest pressure ratios) were definitely as large as their turbine driven counterparts.

Finally, a P-47D with ADI with fuel to provide the same range as that of the 109G/K does not require any larger operating field despite the latter´s "advanced high lift devices" and better power/weight...

[gripen]

Originally posted by Grendel

And yes, I stand by my theory. I've discussed with IRL Bf 109 pilots about their lives overall, and debated about this theory with fellow aviation enthusiasts, and the more we've discussed about the theory the more assured I've became about its validity.

Generally people believe the things which they want to believe.

gripen

[Grendel]

Originally posted by gripen
Generally people believe the things which they want to believe.

That's true, I admit that. I'd like to say, neverthless, that I *have* changed my mind on things when presented with superior argument and I hope to keep my mind open yet for few decades, until Alzheimer or something else comes to rot my mind

[Charge]

"Turbocharging is a very advanced method, it just doesnt pay out for fighters."

I think it does and US AirForces had advantage of them in THEIR strategic situation.

However, I don't see what turbo technology would have given Germans in their situation else than more drain to their already limited resources? And why focus on turbo technology at all when jet technology was already there and could give unsurpassed performance in high alt?

Considering the materials needed in jet engines I think it is logical that turbo technology was given only slight interest in Germany.

-C+

[GScholz]

The turbocharger was invented in 1911 in Switzerland, and it was in limited use in aircraft engines in WWI and in racing engines in the 1920s and '30s. It's not like it was a new technology in WWII.

[joeblogs]

These things weren't really useful until the metalurgy was sorted out in the mid 1930s. Issues of bearings & controls took some time too.

-Blogs

Originally posted by GScholz
The turbocharger was invented in 1911 in Switzerland, and it was in limited use in aircraft engines in WWI and in racing engines in the 1920s and '30s. It's not like it was a new technology in WWII.

[GScholz]

For very high altitude interceptors a turbocharger is preferable to a supercharger because of its flexibility. However for the 0-30k altitude regime the supercharger was deemed most suitable.

The P-38 was designed as a high altitude interceptor. They used a blower in the P-51.

[straffo]

Originally posted by GScholz
The turbocharger was invented in 1911 in Switzerland, and it was in limited use in aircraft engines in WWI and in racing engines in the 1920s and '30s. It's not like it was a new technology in WWII.

Wrong not 1911

It was breveted in 1902 by Louis Renault (studies by Auguste Rateau 1901) and used by Auguste Rateau in 1916/1917
Some SPAD and Bréguet XIV used it.

[GScholz]

Didn't know that. Thanks

[joeblogs]

These were "Roots" blowers yes?

-Blogs

Originally posted by straffo
Wrong not 1911

It was breveted in 1902 by Louis Renault (studies by Auguste Rateau 1901) and used by Auguste Rateau in 1916/1917
Some SPAD and Bréguet XIV used it.

[straffo]

You will need to explain because I don't  now how to translate "root" in this context

[MiloMorai]

Originally posted by straffo
You will need to explain because I don't  now how to translate "root" in this context

Google search

"The principle of the Roots compressor/blower was discovered by two brothers in the mid 1800's. They were Philander H. and Francis M. Roots, joint owners of a woollen mill in Connersville Indiana."

http://www.cashflo.co.uk/Roots.html