"ArtKramr" wrote in message
...
Subject: more radial fans like fw190?
From: "Jukka O. Kauppinen"
Date: 8/19/2004 7:35 AM Pacific Standard Time
Message-id:

The radial on the FW 190 was built on license from Pratt & Whitney.

No.

FW had built Pratt and Whitney engines under license in the earlier
1930s but BMW 139 and the latter BMW 801 used in the FW 190s were BMW's
own designs, not licensed.


Own designs based on what they learned from the P&W license.


The BMW801 was pure BMW Engineering however they no doubt did learn
something from their earlier liscensed production of PW radials. I did
think that the 139 was a PW derivative though I think through the Bramo
company with which BMW united.

The 801 had a innovations such as a multipoint direct in cylinder injection
of the fuel and completely automatic control of mixture and boost. The
pilot only had a throttle to opperate. It's installation in the 190 was
excellent: the engine was tightly cowled to improve aerodynamics with
airflow being provided by a geared fan opperating at about 3:1 to provide
cooling. The exhausts were beautifully installed and provided an ejector
effect to induce cooling and thrust. I believe that only one Soviet fighter
is regarded to have achieved this level of perfection. Around the cowl was a
circular oil tank that was armoured and thus protected the cylinder heads.
It was thus a very tough battle damage resistent engine that provided the
pilot with a massive piece of armour when going in head on against an
american bombers 50s.

The much loved US Gruman Bearcat for instance was inspired and the P47 was
built specifically to deal with the 190.

It's weakness was that its performance dropped of at altitude. The answer
to this was the BMW801T which was turbo supercharged version. Focke-Wulf
built some 190s with the turbo supercharger built into the belly as a bulge
(unlike the P47 it wouldn't fit in the compact fueselage) but they did not
persue the idea perhaps it was inelegant and the turbo metals were in short
supply for such as massively produced aircraft. About 600 of these engines
with a very neat intercooler installation ended up on the Ju388L high
altitude reconaisence bomber where they were very neatly installed with the
intercooler as 5 segments behind the engine. (The Ju388 also had a night
fighter version built to deal with B29s attacking at night)

(The Ju 388 seems to have had the same type of periscopic sighting system as
used on the A26 invader only it had twin 13.1mm MG in a remote tail turret)

However Fock-Wulf decided to install water cooled V12s into the Fw 190 to
get high altitude performance. The 432 mph Fw 190D9 had a jumo 213A
enigine but the Fw190D11 and Fw190D12 (only 70 entered service) had a Jumo
213E engine with the same two stage intercooler arrangement as the Merlin in
the Mustang and could manage 460mph. Oddly for such an engine seems to have
been heavily armoured for ground attack and torpedo bombing (they were used
by the Soviets after the war for this) Apparently the annular radiators of
the German V12s were quite battle damage tollerant as well as aerodynanic.

The same type of engine jumo 213E with more performance ended up in the
475mph TA 152 H0 and TA 152H1 (H-1 had wet fuel tanks in its wooden wings
for greater range) as this had very large wings it could not only fly
extremely high it could out turn any Allied fighter.

You can tell a Fw 190D9 from a Fw 190D11/D12/D13 by the latter lacking cowl
guns and having an oval air intage instead of round and using a cannon
firing through the propeller boss. One of these (The Fw 190 D13 I think)
was to end up with a long barreled Mk 103 30mm cannon as a tank buster. It
was this aircraft that I guess would have finaly replaced the Stuka.






Arthur Kramer
344th BG 494th BS
England, France, Belgium, Holland, Germany
Visit my WW II B-26 website at:
http://www.coastcomp.com/artkramer