Fw-190D-13 "Yellow 10" Restoration
Rob Arndt
What a beauty. JG 26 only received two of these, and there is no known
photos surviving of the other a/c.
Rob
Eunometic
I believe the Soviets, after having captured the Prussian factories of
Fw, continued making some of these equiped with extended tail yokes
that could be used as torpedo bombers and they saw a few years of post
war service in the baltic.
Compared to the Fw 190 D9 the Fw 190 D-13 can be differentiated by:
1 Lack of synchronised machine guns over the cowl, the fire power being
compensated by a motor canon mounted between the engine V firing
through the propeller boss. (The most common Fw 190D-9 used Junkers
Jumo 213A engines surplus from the bomber program that was abandoned
post D-day and did not have the neccessary mounting provisions)
2 The Jumo 213F engine had a 3 speed two stage supercharger compared to
the single stage two speed unit of the Jumo 213A of the Fw 190D-9.
However unlike the 2 stage 3 speed Jumo 213E-1 of the Ta 152H (itself
essentially a Fw-190 with hig aspect ratio large wings wings) there
was no intercooler although high pressure water-methanol injection
provided for charge cooling.
3 Externally the supercharger inlet is oval rather than round,
presumably to provide the extra airflow.
Speed was an impressive 458mph. There were planed versions with a
variety of Junkers 213 or Daimler Benz 603 engines from D-11 through to
D-15.
There was also a Junkers Jumo 213J and 213S(armoured) under-development
with RPM increased to 3200rpm able to produce nearly 3000hp that
probably would have seen speed extended into the 500mph zone. At
some point low altitude variants of the Ta 152C with new wings
optimised for low altitude dog fighting would have taken over from the
Fw-190D series.
Even the old radial engined version was going to get a new wing and a
new powerfull radial (BMW 801 F?) of some 2480hp.
All quite interesting what the engineers had planed as the jet era
began, ofcourse it all came to late to make much difference.
Geoffrey Sinclair
>There was also a Junkers Jumo 213J and 213S(armoured) under-development
>with RPM increased to 3200rpm able to produce nearly 3000hp that
>probably would have seen speed extended into the 500mph zone.
Jumo 213 performance chart,
model / take off HP / cruise HP / RPM
A-1 / 1,725 / unknown / 3,200
B or C / 1,725 / 1,576 / 3,250 (C model similar to A but with engine cannon)
E / 1,750 / 1,320 / 3,200 (Three speed 2 stage supercharger)
F / 2,030 / 1,770 / 3,250 Supercharging like E, but no induction cooler.
J / 2,560 / 1,970 / 3,700 (Projected version)
S / unknown / 2,365 / unknown (Projected version)
The J was meant as the armoured version, the S was to have
4 valves per cylinder (an extra outlet valve). The T version was
to have an exhaust driven turbocharger.
See Junkers Aircraft and Engines by Antony Kay.
Geoffrey Sinclair
Remove the nb for email.
Rob Arndt
fighter a/c than the Fw-190 using both the BMW 802 and 803 engines.
The 802 version of 2,600 hp was conventional and very similar to the
earlier Corsair in layout. The twin-boomed pusher variant was to be
powered by the 803 in the 4,000 hp range.
It should be noted that Fw's last piston fighter design of Feb 20, 1945
was to be powered by a 4,000 hp Argus As-413. It was to be a swept-wing
pushed using contra-props and armed with three 30mm cannons. Projected
max. speed- 509 mph.
FWIW,
Rob
Keith W
"Rob Arndt" <teut...@aol.com> wrote in message
news:1114800410....@g14g2000cwa.googlegroups.com...
Rather reminiscent of the Curtiss XP-55 "Ascender" proposal
of 1940 which was also a swept wing pusher and was
designed for the Pratt & Whitney X-1800 engine.
It too was supposed to be a 500 mph aeroplane, unlike
the FW design Curtiss actually built 4 of the type but
by the time it flew it had no real advantages over
existing aircraft and would be clearly inferior to the
jets being developed and so was dropped
Keith
Dan, U.S. Air Force, retired
Darn the luck, the war ended too soon for you.
Dan, U.S. Air Firce, retired
Rob Arndt
1,275 hp. The first XP-55 was lost on stall trials on 11/15/43. The
other two prototypes flew in 1944.
The XP-55 had a tendency to over-control at low speeds, stall behavior
was bad, and engine cooling was critical. Max. speed?
Only 390 mph with cruising speed being around 250 mph.
I'd say by comparison the Japanese actually got it right with the
Kyushu Shinden... but too late.
Rob
Rob Arndt
my posts. That's why I ended it FWIW.
Yet you still have to push it. Why didn't you comment on the Thread's
title instead and tell us what you thought of the Fw-190D-13
restoration? I guess you can't say anything good about any German
a/c... but that's you. At least some people could see the beauty in it.
~sigh~
Rob
Keith W
> Actually Keith, the three prototypes had Allison V-1710-95 engines of
> 1,275 hp.
I know, thats because the intended engine was never deployed
> The first XP-55 was lost on stall trials on 11/15/43. The
> other two prototypes flew in 1944.
> The XP-55 had a tendency to over-control at low speeds, stall behavior
> was bad, and engine cooling was critical. Max. speed?
> Only 390 mph with cruising speed being around 250 mph.
> I'd say by comparison the Japanese actually got it right with the
> Kyushu Shinden... but too late.
>
> Rob
>
No they didnt
On August 3, 1945 Captain Tsuruno made the first flight. He took the
Shinden aloft only twice more, on the 6th and the 9th of August.
The war ended six days later. In flight, he never raised the landing gear
and the Shinden clocked just 45 minutes of total flying time. These short
flights revealed several potentially serious problems. The airplane pulled
hard right with applications of full engine power at takeoff and the
propeller and drive shaft exhibited strong vibrations.
The aircraft and the second prototype were shipped to the
USA post war but dont seem to have been flown for evaluation
purposes.
Keith
Thom
<keith...@kwillshaw.demon.co.uk> wrote:
>
>"Rob Arndt" <teut...@aol.com> wrote in message
>news:1114814444.8...@z14g2000cwz.googlegroups.com...
>> Actually Keith, the three prototypes had Allison V-1710-95 engines of
>> 1,275 hp.
>
>I know, thats because the intended engine was never deployed
The Allison record shows no serial production of the -95. It jumps
from the -87 to -99
THOM
Dan, U.S. Air Force, retired
<snip>
>I guess you can't say anything good about any German
> a/c... but that's you.
<snip>
> Rob
>
I can and I have, but I recognize they weren't all the best or
prettiest. I was commenting on you once again bringing up yet another
paper aircraft and telling us how it would have performed. It may have
been yet another flop. We will never know.
Dan, U.S. Air Force, retired
Rob Arndt
http://home.att.net/~jbaugher1/p55.html
Rob
p.s. Tons of references on it...
Rob Arndt
All major industrial nations and combatants had paper a/c and
prototypes that were rejected for service.
Why do single out German types?
The USAAF had plenty of paper designs and bad prototypes.
Rob
Dan, U.S. Air Force, retired
I don't single them out. You present them all too many times as proof of
superior German technology and this time the one you presented had
nothing to do with the Fw-190 being restored which is the subject of
this thread.
I am fully aware of some of the loonier designs thought up in other
countries.
Eunometic
opinion he doesn't do as good a job teasing out the story of this
engine as one would hope. Note, at the bottom of column 1 on page 273
in reference to the Jumo 213A:
"MW50 could not be used for takeoffs nor at altitudes above 5000m
(16,400ft). It boosted the manifold pressure sufficiently to give
powers of 2240 hp a sea level, 2000 hp at 3400m and 1880 at 4700m"
In other words the above table that you kindly reproduced does not
include emergency power ratings such as "noteleistung" ( emergency
power) sonder noteleistung (special emergency power) or erhoete
sondernoteleistung (increased special emergency power). PS hope I got
that German spelling right.
The Jumo 213A-1 seen in the Fw 190D-9 appears substantially the same as
the Jumo 213 B & C appart from the lack of mountings for motor canon
and certain provisions for power boosting. In fact the 213 A1 were
diverted from the bomber program and had to be used up first and I
suspect few Dora 9s received these engines.
The 1725 horsepower of the Jumo 213A was hardly better than the BMW 801
radial; however within weeks of entering sevice 3 field modifications
were phased in.
Modification 1: Injection of fuel into the inlet manifold (where the
carburator would be) to produce 1900 hp. I believe this worked by a
charge cooling and rich mixture effect.
The story of this is interesting. The Germans lagged in quality of
fuels in two areas:
Firstly overall octane rating with insufficent plant being available to
synthesise iso-octane and similar components. (they used two different
more combersome process for producing via synthesis high octane fuels
rather than the catalytic upgrading process used by the allies).
Secondly their fuels lacked the aromatic content of British fuels
(which were imported not synthesised I believe; US fuels had a high
octane rating but not a partciularly high rich mixture octane rating).
Lack of aromatics meant that the fuel didn't vaporise well in a
carburator so they had to resort to direct in port fuel injection.
Secondly the aromatic compounds produced a dramatic charge cooling
effect that increase charge density and decreased temperature as well
as producing a rich mixture 'octane rating' that could be used to
overboost the engine.
Fuel injection has advantages but because it is injected into the
cylinders this charge cooling effect is not fully available hence the
modification to add extra fuel to the manifold. The Russians also
favoured fuel injection for this reason I believe.
Modification 2; Low pressure water methanol. I believe this boosted
power to 2100hp.
Modification 2: High pressure water methanol. This boosted power to
2240 hp.
There are unconfitmed stories of one Fw 190 D-9 flown with Nitorus
Oxide injection 'GM-1' but AFAIK only the Ta 152H had this fitted as
standard. Possibly the Fw 190D-12 have GM-1. GM-1 couldn't usually
be used below full pressure altitude of the engine becuase it was set
up to restore power lost rather than boost power.
The Jumo 213J, when I've seen it quoted, is given as having not only an
increase RPM of 3,700 versus 3,200 (18% increase) but also as having 4
instead of 3 valves. (probably an 10-20% increase in valve area as
well). Kay is a bit ambigious on this matter and only notes the 213S
as having the 4 valves. Presumably it also had the two stage 3 speed
supercharger introudced witth the F series.
Given MW50 and some of the other power boosting strategies it is easy
to expect the engine to be producing the 2750-3200 hp it is sometimes
quoted as Junkers projected to getting. (PS I can't find my sources,
still resporing my computer) but it makes sense don't you think)
These variations also seem to give some confustion as to Fw 190D-9
performance. I believe 426 mph was top speed for earlier models
whereas 442 was top speed for later models.
Also worth noting that while the intercooled Jumo 213E-1 of the Ta 152
used 87 B4 octane fuel the non intercooled A and F engines seem to have
mainly used C3 (variously given as 93, 95,98 octane)
Geoffrey Sinclair
Jumo 213 performance chart,
model / take off HP / cruise HP / RPM
A-1 / 1,725 / unknown / 3,200
B or C / 1,725 / 1,576 / 3,250 (C model similar to A but with engine cannon)
E / 1,750 / 1,320 / 3,200 (Three speed 2 stage supercharger)
F / 2,030 / 1,770 / 3,250 Supercharging like E, but no induction cooler.
J / 2,560 / 1,970 / 3,700 (Projected version)
S / unknown / 2,365 / unknown (Projected version)
The J was meant as the armoured version, the S was to have
4 valves per cylinder (an extra outlet valve). The T version was
to have an exhaust driven turbocharger.
See Junkers Aircraft and Engines by Antony Kay.
Eunometic wrote in message <1114871204.4...@f14g2000cwb.googlegroups.com>...
>I've got Kay's book, several of his books in fact, however in my
>opinion he doesn't do as good a job teasing out the story of this
>engine as one would hope. Note, at the bottom of column 1 on page 273
>in reference to the Jumo 213A:
>
>"MW50 could not be used for takeoffs nor at altitudes above 5000m
>(16,400ft). It boosted the manifold pressure sufficiently to give
>powers of 2240 hp a sea level, 2000 hp at 3400m and 1880 at 4700m"
However, since this specifically refers to the Jumo 213A-1 I used
the take off power figures so the different types could be compared.
>In other words the above table that you kindly reproduced does not
>include emergency power ratings such as "noteleistung" ( emergency
>power) sonder noteleistung (special emergency power) or erhoete
>sondernoteleistung (increased special emergency power). PS hope I got
>that German spelling right.
The trouble becomes finding reliable figures for such settings since
they varied according to engine type and whether things like MW 50
or GM 1 were fitted.
>The Jumo 213A-1 seen in the Fw 190D-9 appears substantially the same as
>the Jumo 213 B & C appart from the lack of mountings for motor canon
>and certain provisions for power boosting. In fact the 213 A1 were
>diverted from the bomber program and had to be used up first and I
>suspect few Dora 9s received these engines.
There were some 700 Fw190Ds produced. The 213A engine was in
mass production as a bomber engine, so the D-9 became the modified
Fw190A with 213A engine. The D-12 used the 213F engine. So why
suspect the D-9 mainly received another engine?
As far as I know the Jumo 213A had the space left for a motor cannon,
but could not drive the propeller needed to fit the cannon.
>The 1725 horsepower of the Jumo 213A was hardly better than the BMW 801
>radial;
This ignores the fact the engine performed that bit better at altitude, the
main weakness of the BMW, the A-8 best speed was at around 19,600
feet, the D-9 21,300 feet to use Smith and Kay (18,000 versus 21,600
feet to use Green and Swanborough) and it boosted the top speed by
around 20 mph. Making the fighter more competitive at the USAAF
bomber altitudes.
>however within weeks of entering sevice 3 field modifications
>were phased in.
>
>Modification 1: Injection of fuel into the inlet manifold (where the
>carburator would be) to produce 1900 hp. I believe this worked by a
>charge cooling and rich mixture effect.
Presumably at a cost in range given the fuel was being used more
to cool than burn.
>The story of this is interesting. The Germans lagged in quality of
>fuels in two areas:
>
>Firstly overall octane rating with insufficent plant being available to
>synthesise iso-octane and similar components. (they used two different
>more combersome process for producing via synthesis high octane fuels
>rather than the catalytic upgrading process used by the allies).
"The isoparaffins were produced by standard, well known methods
and there was nothing abnormal found in their compositions. "
and
"Every effort was being made toward the end of the war to increase
isoparaffin production so that C-3 volume could be increased for
fighter plane use. The isoparaffin usage in that grade had already
been cut to a minimum."
The octane ratings were increased by the addition of additives,
but to get the best result the base stock needed to be further
refined, at a cost of a significant amount of total output.
The better refined fuel was then blended with the additives and
the result was higher octane fuel. It looks like you could have
something like 30% less 100 octane than 87 octane, and
possibly 95 octane as well.
And since almost all of Germany's avgas was synthetic, costing
several times fuel made from crude oil you can see the supply
problems. It seems the Germans tried things like higher
concentrations to tetra ethyl lead to boost fuel ratings. The US
went from 3 to 4 cubic centimetres to the gallon in November
1941 to increase the 100 octane rated fuel supply by around 20%.
The Germans were using 4.35 CC per gallon, this caused lead
deposit problems.
Not even the US considered it had enough 100 octane fuel.
>Secondly their fuels lacked the aromatic content of British fuels
>(which were imported not synthesised I believe; US fuels had a high
>octane rating but not a partciularly high rich mixture octane rating).
The allies used natural oil, from the Middle East, Caribbean and the
US to make high octane avgas. There was a joint allied supply.
The USN rates the German C-3 grade as roughly comparable
to the US 100/130 Performance Number grade, the standard
allied fuel for most of the war. It seems in the later war years
maybe 2/3 of the German avgas output was C-3 grade.
> Lack of aromatics meant that the fuel didn't vaporise well in a
>carburator so they had to resort to direct in port fuel injection.
Pre war the Luftwaffe was not as worried about octane ratings,
this changed but it meant it was playing catch up, but it did mean
more work on direct fuel injection. Note the allies standardised
on 80 octane leaded fuels for vehicles, when the Germans were
using 87 octane for aircraft. As octane ratings went up so did
the amount of "aromatics".
>Secondly the aromatic compounds produced a dramatic charge cooling
>effect that increase charge density and decreased temperature as well
>as producing a rich mixture 'octane rating' that could be used to
>overboost the engine.
B-3 had around 10 to 15% aromatics, maximum 25%, C-3 no
more than 45%.
Since the fuel was always cooler than the engine it helped
cooling, but water injection was better as far as I know when
it comes to cooling effects.
B-3, "It contained normally 10 to 15 percent volume aromatics,
45 percent volume naphthenes, and the remainder paraffins. "
C-3. "The C-3 grade was a mixture of 10 to 15 percent volume of
synthetic isoparaffins (alkylates and isooctanes) and 85 percent
of an aromatized base stock produced by hydroforming types of
operation on coal and coal tar hydrogenation gasolines. "
Also,
"The C-3 grade corresponded roughly to the U. S. grade 130
gasoline, although the octane number of C-3 was specified to be
only 95 and its lean mixture performance was somewhat poorer"
See the various papers at www.fischer-tropsch.org
>Fuel injection has advantages but because it is injected into the
>cylinders this charge cooling effect is not fully available hence the
>modification to add extra fuel to the manifold. The Russians also
>favoured fuel injection for this reason I believe.
>
>Modification 2; Low pressure water methanol. I believe this boosted
>power to 2100hp.
The question is which engine, Kay notes MW 50 figures for the 213A-1
engine.
>Modification 2: High pressure water methanol. This boosted power to
>2240 hp.
The engine always had the capacity for effectively water cooling and
the 213A-1 rating was 2,240 HP at sea level with the cooling.
>There are unconfitmed stories of one Fw 190 D-9 flown with Nitorus
>Oxide injection 'GM-1' but AFAIK only the Ta 152H had this fitted as
>standard. Possibly the Fw 190D-12 have GM-1. GM-1 couldn't usually
>be used below full pressure altitude of the engine becuase it was set
>up to restore power lost rather than boost power.
The Jumo 213 series started out with nitrous oxide capacity given the
bombers used it. Be aware the system cost, the Ju88S version
weighed in at 900 pounds. It is very unlikely the Fw190D carried GM-1,
the better answer was better supercharging. The Ta152H carried it
along with the very long wings because of the altitude it was designed
to fight at.
All supercharging has an altitude below which it is not helping.
>The Jumo 213J, when I've seen it quoted, is given as having not only an
>increase RPM of 3,700 versus 3,200 (18% increase) but also as having 4
>instead of 3 valves. (probably an 10-20% increase in valve area as
>well). Kay is a bit ambigious on this matter and only notes the 213S
>as having the 4 valves. Presumably it also had the two stage 3 speed
>supercharger introudced witth the F series.
Simply put since the S version was not built it "could" have had anything.
>Given MW50 and some of the other power boosting strategies it is easy
>to expect the engine to be producing the 2750-3200 hp it is sometimes
>quoted as Junkers projected to getting. (PS I can't find my sources,
>still resporing my computer) but it makes sense don't you think)
Given the way different fuels were used and different superchargers
as well on the various engines I would be very wary of claiming what
each engine would do. In any case the claim was the engine did
produce the power, at over 3,00 HP, not that it might have and maybe
around 2,700 HP.
The claim was,
"There was also a Junkers Jumo 213J and 213S(armoured) under-
development with RPM increased to 3200rpm able to produce nearly
3000hp "
>These variations also seem to give some confustion as to Fw 190D-9
>performance. I believe 426 mph was top speed for earlier models
>whereas 442 was top speed for later models.
There are always going to be variations in top speed, the build quality
of German aircraft in 1944/45 left a lot to be desired. Note the MW 50
boosts were for low or medium altitude, and the best speed was above
20,000 feet. So an increase in top speed means an increase in power
above 20,000 feet.
>Also worth noting that while the intercooled Jumo 213E-1 of the Ta 152
>used 87 B4 octane fuel the non intercooled A and F engines seem to have
>mainly used C3 (variously given as 93, 95,98 octane)
So the E-1 in effect tried to use an induction cooler to enable the lower
grade fuel.
Eunometic
I appreciate that. I wasn't criticising your presentation, just
emphasising out we don't seem to have clear MW-50 ratings for the jumo
213F or the projected jumo 213J and Jumo 213S . The table above in the
column for takeoff power clearly doesn't include application of Water
Methanol MW-50 for the Jumo 213A or any of the other boosting measures.
I recall (sorry from somewhere) that from 2700hp and expectation of
over 3000hp was anticipated for the Jumo 213J or S. This puts it in the
same range as the Griffon. Both engines being about the same volume
and both stepping up from single stage to two stage superchargers.
>
> >In other words the above table that you kindly reproduced does not
> >include emergency power ratings such as "noteleistung" ( emergency
> >power) sonder noteleistung (special emergency power) or erhoete
> >sondernoteleistung (increased special emergency power). PS hope I
got
> >that German spelling right.
>
> The trouble becomes finding reliable figures for such settings since
> they varied according to engine type and whether things like MW 50
> or GM 1 were fitted.
Comprehensive data for the Jumo 213A-1 of the Fw 190D-9 is available
though you have to be aware of the 3 field modifications carried out to
increase emergency boost power to make sense of them. Comprehensive
data is also available for the jumo 213E-1 of the Ta152H in this case
with MW50 or GM-1 or both since it was tested by the allies after the
war.
Ratings for the Jumo 213F aren't as clear except to say that it has a
full pressure altitude of 9500m instead of 5500m but approximetly the
same power. It may simply be that this engines improvements lie mainly
in the area of better high altitude performance. It may be that this
engine does allow MW-50 at takeoff whereas the A does not.
>
> >The Jumo 213A-1 seen in the Fw 190D-9 appears substantially the same
as
> >the Jumo 213 B & C appart from the lack of mountings for motor canon
> >and certain provisions for power boosting. In fact the 213 A1 were
> >diverted from the bomber program and had to be used up first and I
> >suspect few Dora 9s received these engines.
>
> There were some 700 Fw190Ds produced. The 213A engine was in
> mass production as a bomber engine, so the D-9 became the modified
> Fw190A with 213A engine. The D-12 used the 213F engine. So why
> suspect the D-9 mainly received another engine?
I suspect, from Kays wording, a few ended up with Jumo 213C's but most
with Jumo 213A.
>
> As far as I know the Jumo 213A had the space left for a motor cannon,
> but could not drive the propeller needed to fit the cannon.
The only difference between an A and a C was the oil distribution for
the variable pitch mechanism.
>
> >The 1725 horsepower of the Jumo 213A was hardly better than the BMW
801
> >radial;
>
> This ignores the fact the engine performed that bit better at
altitude, the
> main weakness of the BMW, the A-8 best speed was at around 19,600
> feet, the D-9 21,300 feet to use Smith and Kay (18,000 versus 21,600
> feet to use Green and Swanborough) and it boosted the top speed by
> around 20 mph. Making the fighter more competitive at the USAAF
> bomber altitudes.
I think these figures would include the note leistung.
There is comprehensive tables available here:
http://jagdhund.homestead.com/files/Dora.htm
This also gives a fairly good summary of boosting kits used on the Jumo
213.
This is one of the few tables. It shows a maximum speed of 438mph at
5500 meters which is also full pressure altitude.
http://jagdhund.homestead.com/files/DoraData/horizontalgeschwindigkeiten.htm
If GM-1 was used (and it may or may not have been but test data is
available speed of 443 mph is maintained to 11000m. effectively GM-1
doubles the full pressure altitude.
http://jagdhund.homestead.com/files/DoraData/speeds_with_gm.htm
>
> >however within weeks of entering sevice 3 field modifications
> >were phased in.
> >
> >Modification 1: Injection of fuel into the inlet manifold (where
the
> >carburator would be) to produce 1900 hp. I believe this worked by a
> >charge cooling and rich mixture effect.
>
>
> Presumably at a cost in range given the fuel was being used more
> to cool than burn.
Yes. Effectively they ran a multi-point direct in cylinder fuel
injections system using variable displacement pumps and then to get
extra power by a charge cooling effect added a sort of crude throttle
body central fuel injection system in a similar position to to the one
on the Merlin/Griffon. It appears to have used C3 rather than B4 fuel.
This makes sense as C3 had a high aromatic content as you pointed out
and so would have a very high cooling effect. It may even be that the
main engine ran of B4 but used C3 for boosting since data for B4 shows
that it produced 1725hp takeoff power.
The Merlin Griffon I believe ended up with a system using swash plate
opperated variable displacement pumps with adjustment for throttle
position and compensation for altitude, exhaust temperature.
This central fuel injection syastem provides a natural cooling effect.
RR didn't want to loose this so this was one reason they never went to
multipoint injection during the war. Kay also says that the Germans
weren't confident of producing Carburators since they were too well
developed in the UK and USA.
The Germans were certainly in awe of engines such as the Kestrel.
The fuel injection allows freedom from freezing, immunity to poor
vaporisation from inferior fuels and allows the inlet and exhaust
valves to be phased for a resonant scavenging effect so that both
valves are concurrently open thus scavenging the final amount of
exhaust and replaceing it with a an air charge without loosing any fuel
air mixture.
On the other hand although rich mixture octane responses are improved
when running rich mixtures the valuable charge cooling effect is
absent.
>
> >The story of this is interesting. The Germans lagged in quality of
> >fuels in two areas:
> >
> >Firstly overall octane rating with insufficent plant being available
to
> >synthesise iso-octane and similar components. (they used two
different
> >more combersome process for producing via synthesis high octane
fuels
> >rather than the catalytic upgrading process used by the allies).
>
> "The isoparaffins were produced by standard, well known methods
> and there was nothing abnormal found in their compositions. "
>
> and
>
> "Every effort was being made toward the end of the war to increase
> isoparaffin production so that C-3 volume could be increased for
> fighter plane use. The isoparaffin usage in that grade had already
> been cut to a minimum."
>
> The octane ratings were increased by the addition of additives,
> but to get the best result the base stock needed to be further
> refined, at a cost of a significant amount of total output.
>
> The better refined fuel was then blended with the additives and
> the result was higher octane fuel. It looks like you could have
> something like 30% less 100 octane than 87 octane, and
> possibly 95 octane as well.
So for the same amount of coal and investment in plant and FLAK to
protect that plant you could have 100 units of B4 versus only 70 units
of C3. That would make C3 100/70-1 = 40% more expensive and requiring
40% more plant.
>
> And since almost all of Germany's avgas was synthetic, costing
> several times fuel made from crude oil you can see the supply
> problems. It seems the Germans tried things like higher
> concentrations to tetra ethyl lead to boost fuel ratings. The US
> went from 3 to 4 cubic centimetres to the gallon in November
> 1941 to increase the 100 octane rated fuel supply by around 20%.
> The Germans were using 4.35 CC per gallon, this caused lead
> deposit problems.
>
> Not even the US considered it had enough 100 octane fuel.
There appears to have been a daily peek production of 50,000 barrels
without disruption. (a barrel is about 158L or 128kg or 320lbs of
fuel). By my reckoning that allows for about 10,000 1 hour single
engined fighter sorties.
>
> >Secondly their fuels lacked the aromatic content of British fuels
> >(which were imported not synthesised I believe; US fuels had a high
> >octane rating but not a partciularly high rich mixture octane
rating).
>
> The allies used natural oil, from the Middle East, Caribbean and the
> US to make high octane avgas. There was a joint allied supply.
The Houdry process, developed by a Frenchmen in the US for catalytic
upgrading. There also appears to be a BP developed process.
>
> The USN rates the German C-3 grade as roughly comparable
> to the US 100/130 Performance Number grade, the standard
> allied fuel for most of the war. It seems in the later war years
> maybe 2/3 of the German avgas output was C-3 grade.
>From my reading of the Fischer Tropsch archives the rating would seem
to work out as 95/130.
This is a suprise to me. This is quite a good rating. Apparently a
relatively pure octane would have been an ideal fuel for the German
engines so they had good rich ratings but poor lean ratings so their
cruise fuel efficiency would have suffered about 5%.
Whether this tells the full story is another matter but it would seem
to contradict the general impression that the Germans had a shortage of
C3 fuel versus B4 fuel. They had a shortage of all fuel but strenious
efforts must have been made to limit C3 consummption as it cost so much
in therms of resources compared to B4.
I believe the BMW radial of some tansport aircraft had seperate C3 and
B4 tanks thus allowing over boost on the more precious fuel only during
takeoff.
I take an interest in this area. The 12 or so big hydrogenation plants
were vulnerable to bombing becuase they couldn;t be hidden or reduced
in size (becuase they opperated at 700 bar). The 12 main Fischer
Tropsch plants were only about 1/5th the size. In addition there were
about 42 mini fischer trospch plants that could be hidden becuase they
opperated at only some 10 bar and were lightly constructed, however
their fuel grade was low and usefull only for chemical feedstock and
Army grad fuels of about 77 octane and diesel. Some 42 mini plants
were so well hidden they were never found but they were only able to
produce army fuel.
It looks like from this they were heading towards direct synthesis of
iso-octane from syn gas by increasinly efficient prcesses produced it
in dispersed smaller plants as well.
http://www.fischer-tropsch.org/Bureau_of_Mines/tom_meeting/butane_hydrogen.htm
>
> > Lack of aromatics meant that the fuel didn't vaporise well in a
> >carburator so they had to resort to direct in port fuel injection.
>
> Pre war the Luftwaffe was not as worried about octane ratings,
> this changed but it meant it was playing catch up, but it did mean
> more work on direct fuel injection. Note the allies standardised
> on 80 octane leaded fuels for vehicles, when the Germans were
> using 87 octane for aircraft. As octane ratings went up so did
> the amount of "aromatics".
German "Army" fuel I believe was rated 72 or 77 octane. Goering began
demanding large amounts of C3 from 1939 onwards I believe though it
must have been a long time in comming.
The introduction of the BMW801D in the Fw 190A3 and the Me 109F would
seem to mark the introduction of C3 coincident with a 10% increase in
power but with a black flip to B4 occuring with the 109G while the Fw
190A continued on with C3. The Fw 190D-9 had at least the option of
running of B4.
>
> >Secondly the aromatic compounds produced a dramatic charge cooling
> >effect that increase charge density and decreased temperature as
well
> >as producing a rich mixture 'octane rating' that could be used to
> >overboost the engine.
>
> B-3 had around 10 to 15% aromatics, maximum 25%, C-3 no
> more than 45%.
>
> Since the fuel was always cooler than the engine it helped
> cooling, but water injection was better as far as I know when
> it comes to cooling effects.
The Americans used water injection on the P-47 but the British never
seem to have gone for it prefering higher octane fuels. Water-Methanol
added weight and complexity and displaced fuel. (The MW50 tanks could
be used for fuel if the MW50 was deemed unnecesary for ferry flights
for instance.)
>
> B-3, "It contained normally 10 to 15 percent volume aromatics,
> 45 percent volume naphthenes, and the remainder paraffins. "
>
> C-3. "The C-3 grade was a mixture of 10 to 15 percent volume of
> synthetic isoparaffins (alkylates and isooctanes) and 85 percent
> of an aromatized base stock produced by hydroforming types of
> operation on coal and coal tar hydrogenation gasolines. "
>
> Also,
>
> "The C-3 grade corresponded roughly to the U. S. grade 130
> gasoline, although the octane number of C-3 was specified to be
> only 95 and its lean mixture performance was somewhat poorer"
>
> See the various papers at www.fischer-tropsch.org
>
> >Fuel injection has advantages but because it is injected into the
> >cylinders this charge cooling effect is not fully available hence
the
> >modification to add extra fuel to the manifold. The Russians also
> >favoured fuel injection for this reason I believe.
> >
> >Modification 2; Low pressure water methanol. I believe this
boosted
> >power to 2100hp.
>
> The question is which engine, Kay notes MW 50 figures for the 213A-1
> engine.
They were field modifications fitted by Luftwaffe technicians or in the
case of the High pressure water methanol system it was fitted by
junkers technicians since it required a new control system. The
designation Jumo 213A would probably remain though there must be
another set of seriel numbers eg someting like Jumo 213A-2 or R1 to
denote the upgrade.
>
> >Modification 2: High pressure water methanol. This boosted power to
> >2240 hp.
>
> The engine always had the capacity for effectively water cooling and
> the 213A-1 rating was 2,240 HP at sea level with the cooling.
Yes MW50 could be used a sea level on the Jumo 213A but not at takeoff
according to Kay. Technically the only reason I can come up with is
the limited cooling flow available at takeoff overt he oil cooler and
radiator. At low speeds this could thermally over stress the engine.
MW50 was time limited to a few minutes (20 or so) presumably becuase of
thermal considerations or spark plug fouling issues.
>
> >There are unconfitmed stories of one Fw 190 D-9 flown with Nitorus
> >Oxide injection 'GM-1' but AFAIK only the Ta 152H had this fitted as
> >standard. Possibly the Fw 190D-12 have GM-1. GM-1 couldn't
usually
> >be used below full pressure altitude of the engine becuase it was
set
> >up to restore power lost rather than boost power.
>
> The Jumo 213 series started out with nitrous oxide capacity given the
> bombers used it. Be aware the system cost, the Ju88S version
> weighed in at 900 pounds. It is very unlikely the Fw190D carried
GM-1,
> the better answer was better supercharging. The Ta152H carried it
> along with the very long wings because of the altitude it was
designed
> to fight at.
The Fw 190D-9 was fitted and tested with GM-1 as data is available but
whether or not it was flown in combat is another matter. Speed was
life.
Me 109G/K did use GM-1 however.
Kay claims that at some point GM-1 was made "bullet proof" i.e.
explosion resistent and this made it popular again.
>
> All supercharging has an altitude below which it is not helping.
Depends on the set up and fuel? eg supercharger gear ratios. There is
a rather nice convertible that is a product of Daimler-Chrysler that
has a "Kompressor" that works to boost sea level power quite nicely.
>
> >The Jumo 213J, when I've seen it quoted, is given as having not only
an
> >increase RPM of 3,700 versus 3,200 (18% increase) but also as having
4
> >instead of 3 valves. (probably an 10-20% increase in valve area as
> >well). Kay is a bit ambigious on this matter and only notes the
213S
> >as having the 4 valves. Presumably it also had the two stage 3
speed
> >supercharger introudced witth the F series.
>
> Simply put since the S version was not built it "could" have had
anything.
>
> >Given MW50 and some of the other power boosting strategies it is
easy
> >to expect the engine to be producing the 2750-3200 hp it is
sometimes
> >quoted as Junkers projected to getting. (PS I can't find my
sources,
> >still resporing my computer) but it makes sense don't you think)
>
> Given the way different fuels were used and different supercharger
> as well on the various engines I would be very wary of claiming what
> each engine would do. In any case the claim was the engine did
> produce the power, at over 3,00 HP, not that it might have and maybe
> around 2,700 HP.
>
> The claim was,
>
> "There was also a Junkers Jumo 213J and 213S(armoured) under-
> development with RPM increased to 3200rpm able to produce nearly
> 3000hp "
Well, I've have to dig up my sources but I must admit to having some
doubts about the 3200hp statement but the 2700 pretty sure of. The
developments after the Jumo 213A such as the F and E series were the
addition of two stage superchargers that didn't do much for sea level
power but did increase full pressure height. Perhaps they even reduced
performance at low altitude
>
> >These variations also seem to give some confustion as to Fw 190D-9
> >performance. I believe 426 mph was top speed for earlier models
> >whereas 442 was top speed for later models.
>
> There are always going to be variations in top speed, the build
quality
> of German aircraft in 1944/45 left a lot to be desired. Note the MW
50
> boosts were for low or medium altitude, and the best speed was above
> 20,000 feet. So an increase in top speed means an increase in power
> above 20,000 feet.
There is comprehensive tables available here:
http://jagdhund.homestead.com/files/Dora.htm
This also gives a fairly good summary of boosting kits used on the Jumo
213.
>
> >Also worth noting that while the intercooled Jumo 213E-1 of the Ta
152
> >used 87 B4 octane fuel the non intercooled A and F engines seem to
have
> >mainly used C3 (variously given as 93, 95,98 octane)
>
> So the E-1 in effect tried to use an induction cooler to enable the
lower
> grade fuel.
I think its fair to say the intercooler, which reduced temperature by
30%, had this effect. The non intercooled F series engines which also
had two stage 3 speed superchargers seem to have almost same
performance, about 3-5% less, without the intercooler but with the
higher grade fuel but were ofourse about 150kg lighter and shorter.
http://www.focke-wulf190.com/indexneu.htm
While most sources (eg War prizes) mention the use of B4 as standard I
would question whether it might still be able to take advantage of C3.
It appears that the late model Me 109K and G could use either B4 or C3
by adjusting its maxiumum boost pressure with 2000hp being available
with C3 and 1800hp without.
oddly I've never ever come across a Luftwaffe Pilots account where he
has complained of being ony given B4 instead of C3.
Eunometic
Geoffrey Sinclair wrote:
> To restore the table being mentioned,
>
> Jumo 213 performance chart,
>
> model / take off HP / cruise HP / RPM
>
> A-1 / 1,725 / unknown / 3,200
> B or C / 1,725 / 1,576 / 3,250 (C model similar to A but with engine
cannon)
> E / 1,750 / 1,320 / 3,200 (Three speed 2 stage supercharger)
> F / 2,030 / 1,770 / 3,250 Supercharging like E, but no induction
cooler.
> J / 2,560 / 1,970 / 3,700 (Projected version)
> S / unknown / 2,365 / unknown (Projected version)
>
I believe a book by Dietmar Hermann's on the Ta 152 book states that
the Jumo 213J projected power was to be 2700 HP (or PS?). The 213S
should have had even more so. Presumably this was with all possible
short term power boosting methods in play.
The book is available from Amazon and seems to get good reviews. My
sources seem to have been a newsboard discusion.