Luftwaffe and Allied Air Forces Discussion Forum  

Go Back   Luftwaffe and Allied Air Forces Discussion Forum > Discussion > Luftwaffe and Axis Air Forces

Luftwaffe and Axis Air Forces Please use this forum to discuss the German Luftwaffe and the Air Forces of its Allies.

Reply
 
Thread Tools Display Modes
  #1  
Old 2nd January 2009, 01:35
kennethklee kennethklee is offline
Member
 
Join Date: Feb 2005
Posts: 91
kennethklee
Focke-Wulf Fw 190A poor high-altitude performance

The poor performance of the Fw 190A above 20,000 feet is well-known. As best I could ascertain, the reason for this limitation was ineffective superchargers for the Fw 190's BMW radial engine. The Republic P-47 Thunderbolt had excellent high-altitude performance with its radial engine, which was attributed to a large degree to its supercharger. The Germans seem to have effective superchargers for their inline Daimler-Benz and Junkers Jumo engines, so I am curious why an effective supercharger was not able to be developed for the BMW radial engine. (Searching on Google was fruitless for me.) Am I missing the real reason(s) for the poor performance of the Fw 190A at altitude?

Thanks,
Kenneth
Reply With Quote
  #2  
Old 2nd January 2009, 03:10
John Beaman John Beaman is offline
Super Moderator
 
Join Date: Dec 2004
Location: Greensboro, North Carolina, USA
Posts: 2,130
John Beaman is an unknown quantity at this point
Re: Focke-Wulf Fw 190A poor high-altitude performance

The P-47 was the happy recipient of a lot of research and experiments by the USAAF with turbo-superchargers (exhaust driven) and was, therefore, ready for high-altitude combat.

The Germans, on the other hand, never anticipated the WWII high altitude combat that resulted from the USAAF’s high altitude bombing campaign. Recall, that the DB 601 engine was developed in the late 19030s when medium altitude combat was the expected norm. The DB engines were not that great over 20k feet, hence the eventual addition of GM-1 to the DB 601 and 605 for high altitude performance and eventually, the make-shift AS types. This was also true of the RR Merlin which did not have effective high-altitude performance until the Merlin 61(?) in the Spitfire IX. Superchargers for in-line liquid cooled engines were much simpler to develop than for radial engines, hence all the work by the US on the turbo superchargers—it was tedious work. The Germans never made that much effort for radials until the Fw 190 experiments which resulted in nothing for the BMW radials. It was simpler, easier and quicker to do the D-9, pending the Ta 152.

Bottom line: the need was not anticipated and money for experiments was always a big issue for the pre-war Luftwaffe. Goering and Hitler wanted a strong air force, now, not a few years down the road.
Reply With Quote
  #3  
Old 2nd January 2009, 07:44
kb kb is offline
Senior Member
 
Join Date: Dec 2004
Posts: 111
kb
Re: Focke-Wulf Fw 190A poor high-altitude performance

IIRC US Navy/USMC radial engine fighters (F4F, F6F, F4U) had similar performance drop offs to the 190A at high altitude.
Reply With Quote
  #4  
Old 2nd January 2009, 11:23
Graham Boak Graham Boak is offline
Alter Hase
 
Join Date: Jan 2005
Location: Lancashire, UK
Posts: 1,602
Graham Boak is on a distinguished road
Re: Focke-Wulf Fw 190A poor high-altitude performance

It is not a function of radial engines. It is largely a matter of superchargers and the maximum compression ratio. All single-stage supercharger engines begin running out of power around 20000ft. The radial BMW 801 was no different to the inline Sabre, hence the problems with accepting the Typhoon into a Fighter Command that increasingly emphasised high-altitude performance. For performance at higher altitudes the US went to turbochargers, the UK to two-stage superchargers, the Germans to exotic fuel additives. This was partly a matter of available materials, turbochargers requiring exotic metals the Germans lacked; and available expertise, RR being particularly good with superchargers.

For additional altitude, aerodynamic advantage can be gained from larger wings, either by increased span or greater aspect ratio (span divided by mean chord, or span squared over wing area). The Fw 190 has a low aspect ratio wing, so loses out here. Consider the Ta 152H.....
Reply With Quote
  #5  
Old 2nd January 2009, 11:28
Harri Pihl Harri Pihl is offline
Senior Member
 
Join Date: Aug 2006
Location: Finland
Posts: 110
Harri Pihl is on a distinguished road
Re: Focke-Wulf Fw 190A poor high-altitude performance

Focke Wulf and BMW planned to add the turbo charger but these developements never went beyond experimental stage. IIRC the only plane which reached more or less experimental service with the BMW turbo charged engine was the Ju 388.
Reply With Quote
  #6  
Old 2nd January 2009, 11:35
Harri Pihl Harri Pihl is offline
Senior Member
 
Join Date: Aug 2006
Location: Finland
Posts: 110
Harri Pihl is on a distinguished road
Re: Focke-Wulf Fw 190A poor high-altitude performance

Quote:
Originally Posted by Graham Boak View Post
For performance at higher altitudes the US went to turbochargers, the UK to two-stage superchargers, the Germans to exotic fuel additives. This was partly a matter of available materials, turbochargers requiring exotic metals the Germans lacked; and available expertise, RR being particularly good with superchargers.
The Germans were going towards two stage mechanical superchargers as well. There were numerous such projects, the development was just slow. The Jumo 213E was the only such engine to reach the service in some degree.
Reply With Quote
  #7  
Old 2nd January 2009, 11:42
Graham Boak Graham Boak is offline
Alter Hase
 
Join Date: Jan 2005
Location: Lancashire, UK
Posts: 1,602
Graham Boak is on a distinguished road
Re: Focke-Wulf Fw 190A poor high-altitude performance

And Allison did a two-stage supercharger, which saw production in the P-63, and postwar in the F-82.

It is worth pointing out that phrases such as "poor high-altitude performance" is only meaningful comparated to those aircraft with turbochargers or two-stage superchargers. The Fw 190 was superior to the Yaks and Lavochkins it faced on the Eastern front, although curiously it does not seem to have gained the same reputation in the East that it had in the West. A supercharger design is set to a given pressure, and hence a given fixed throttle height. Witness the "cropped" LF series of Merlins, which gave the Spitfire LF Mk.V possibly the highest low-level climb rate of any WW2 service fighter, but reached its maximum power at only 5000ft.
Reply With Quote
  #8  
Old 2nd January 2009, 13:11
Ruy Horta's Avatar
Ruy Horta Ruy Horta is offline
He who rules the forum...
 
Join Date: Dec 2004
Location: Amstelveen, The Netherlands
Posts: 1,467
Ruy Horta has disabled reputation
Re: Focke-Wulf Fw 190A poor high-altitude performance

Kenneth,

I suggest you take a look at:

Focke-Wulf Fw 190A
Die Ersten Baureihen
Dietmar Hermann, Ulrich Leverenz & Eberhard Weber
Aviatic Verlag, 2002
3-925505-72-5
Laminated, 222p

Focke-Wulf Fw 190 "Long Nose"
An illustrated history of the Fw 190 D series
Dietmar Hermann
Schiffer Publishing, 2003
0-7643-1876-4
Hard Cover, 206p

Focke-Wulf Höhenjäger
Vom ersten Höhenjäger zur Fw 190 H
Jet & Prop Typen-Chronik 6 Spezial
Dietmar Hermann
VDM, 2002
3-925480-XX-X
Softcover, 132p

The first title is also available in English as published by Schiffer (I usually by original German if I have a choice).

These three books cover your questions regarding the Fw 190 and high altitude performance.

Issues as design philosophy, impact of the RLM, engine and supercharger research are all covered. The Fw 190 was seen by Tank as a flexible frame for a work horse.
__________________
Ruy Horta
12 O'Clock High!

And now I see with eye serene
The very pulse of the machine;
A being breathing thoughtful breath,
A traveller between life and death;
Reply With Quote
  #9  
Old 2nd January 2009, 14:43
Jim Oxley's Avatar
Jim Oxley Jim Oxley is offline
Senior Member
 
Join Date: Mar 2005
Location: Canberra, ACT, Australia
Posts: 525
Jim Oxley is on a distinguished road
Re: Focke-Wulf Fw 190A poor high-altitude performance

Thanks for those book recommendations Ruy, I've been looking for quality books on the Fw190 for ages.

Btw, what does IIRC mean?
Reply With Quote
  #10  
Old 2nd January 2009, 15:09
John Beaman John Beaman is offline
Super Moderator
 
Join Date: Dec 2004
Location: Greensboro, North Carolina, USA
Posts: 2,130
John Beaman is an unknown quantity at this point
Re: Focke-Wulf Fw 190A poor high-altitude performance

Quote:
Originally Posted by Jim Oxley View Post
Thanks for those book recommendations Ruy, I've been looking for quality books on the Fw190 for ages.

Btw, what does IIRC mean?
"If I Recall Correctly"
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Performance of the Fw 190A on the Deck? Boomerang Luftwaffe and Axis Air Forces 173 11th August 2008 10:30
I'm seeking these 1/48 kits ! jmarcpe Wanted 0 26th April 2008 18:41
Focke Wulf FW 190 D Camouflage & Markings Vol.2 Rudi Penker Luftwaffe and Axis Air Forces 0 19th September 2007 20:14
Aircraft performance curves Christer Bergström Luftwaffe and Axis Air Forces 17 19th November 2005 22:49
Low altitude tests: P-47 vs. Fw 190 Six Nifty .50s Luftwaffe and Axis Air Forces 4 20th April 2005 01:13


All times are GMT +2. The time now is 09:00.


Powered by vBulletin® Version 3.7.2
Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.
Copyright ©2004 - 2018, 12oclockhigh.net