Author Topic: BMW801D2 Horsepower at 1.62ata (Read 9117 times)

Wotan · « **Reply #45 on:** July 30, 2004, 12:05:43 PM »

Thats what I had think to niklas.

C3 injection worked by cooling the heads through injecting fuel into the supercharger. LOTS of fuel.

C3 injection consumed about 70l of fuel per 5 min of the 190's onboard fuel.

The Flugzeug-Handbuch (A-5 bis A-6 and A-7 bis A-9) says to run it "as long as the emergency last's". Even with the 115l tank and DT 1.65 ata it could run as long as there is fuel. Without the 115l tank range would be extremely reduced when running C3 injection.

I had thought that C3 injection was drawn from the aux tank but it is bled right from the fuel line.

Quote

From Janes:

"The pilot had a small push-pull control which operated two c o c k s. The first c o c k opened an air bleed in the boost pressure regulator chamber, causing the regulator to open the butterfly throttle to provide +8.8 lb. boost instead of +5.5 lb. boost at sea level. The second c o c k opened a pipe line from the fuel pump to a spray nozzle fitted in the port air intake.

Crumpp · « **Reply #46 on:** July 30, 2004, 05:15:16 PM »

The tank was optional in the FW-190A8. The manual is clear on that.

The 190A5 was the first to use C3 boost. At least it was the first to include instructions for C3 use in the manual.

The FW-190A5 could use 1.58/1.65ata ONLY when it was equipped with C3. It was limited to 10-15 minutes of use. This is probably due to the high fuel consumption of C3. Without C3 installed the 190A5 was limited to 1.42ata for 3 minutes and unlimted on 1.32ata. It could NOT use 1.58/1.65ata at all. The FW-190A5 was not equipped to use the 115 liter aux tank.

The FW-190A8 was able to use 1.58ata/1.65ata for 10 minutes WITHOUT the installation of C3 boost. It was unlimited on 1.42ata.

WITH C3 installed the 190A8 could use it "as long as the emergency last's". The 115 aux tank would have give the 190A8 an extra 6-8 minutes of 1.58/1.65ata but it drew fuel from the main fuel pump and was not dependant on any special tank. installation of the tank added 120kg to the weight of the 190A8. 90kg of fuel and 30kg of tank/fittings.

Crumpp

VO101_Isegrim · « **Reply #47 on:** July 30, 2004, 06:00:58 PM »

Crummp,

would it be possible to see a weight breakdown on the A-8, how much guns, extra tanks, racks etc. added?

Even better if you could send the relevant performance/weight part to executor@index.hu , I could use that for my site (109K performance comparison with it`s rivals, including the 190A/D)

Crumpp · « **Reply #48 on:** July 31, 2004, 09:19:29 PM »

I tried to send you all three. The FW-190A3, FW-190A5 and the FW-190A8 so you could see the weight breakdowns.

They are for your personal knowledge. You can share facts but not the docs please.

Soon as you empty your mailbox I will send you the A8 weights.

Take care.

Crumpp

Crumpp · « **Reply #49 on:** July 31, 2004, 09:35:38 PM »

BTW,

The FW-190A5 using C3 boost had a different fuel consumption rate than the C3 boost on the A8.

The C3 boost on the FW-190A5 used two different spray nozzles at the injector. One consumed 20 liters an hour and the other consumed 23 liters and hour. This is why using C3 boost the FW-190A5 is limited to 10-15 minutes @ 1.65ata.

FW-190A8 C3 boost dumped a lot more fuel in the supercharger and therefore kept the engine cooler. Hence it's time @ 1.65ata was "as long as the emergency lasted".

Crumpp

sfuchs · « **Reply #50 on:** August 15, 2004, 04:21:21 AM »

Hello,

I'm new to the forum and a bit confused about the subject. In the flight manual of the Fw 190 A is written that the "increased emergency power" should only be used in heights up to 1 km. It also states that the engine runs at 1,65 ata and consumes 70 litre of C3 in 5 minutes at "increased emergency power".

The figures posted in this thread show a setting of 1,58 ata for the low gear and 1,65 ata for the high gear - but as far as I understand it shouldn't be used in high gear and the engine should be at 1,65 ata when used (and not 1,58 ata).

Can someone tell more about this ? Was the usage only restricted in early versions (in the A5) and a changed system without these restrictions installed to later versions (as the A8) ? Are the restrictions posted in the manual only for the A5 ? The manual is the "Bedienungsvorschrift-Fl Fw 190 A-1 bis A-8 L.Dv.T. 2190 A-1 bis A-8/Fl".

As Crumpp already pointed there was a difference in the fuel injection beween the A5 and the A8, are there other differences in the system as well ?

- sfuchs -

Crumpp · « **Reply #51 on:** August 15, 2004, 10:33:02 AM »

Quote

The figures posted in this thread show a setting of 1,58 ata for the low gear and 1,65 ata for the high gear - but as far as I understand it shouldn't be used in high gear and the engine should be at 1,65 ata when used (and not 1,58 ata).

The two stage supercharger is not set by the pilot. It is an automatic function that kicks in when the ambient pressure drops and increased pressure is required to feed the motor.

Quote

I'm new to the forum and a bit confused about the subject. In the flight manual of the Fw 190 A is written that the "increased emergency power" should only be used in heights up to 1 km. It also states that the engine runs at 1,65 ata and consumes 70 litre of C3 in 5 minutes at "increased emergency power".

It should not be used BELOW 1 km.

Quote

Can someone tell more about this ? Was the usage only restricted in early versions (in the A5) and a changed system without these restrictions installed to later versions (as the A8) ? Are the restrictions posted in the manual only for the A5 ? The manual is the "Bedienungsvorschrift-Fl Fw 190 A-1 bis A-8 L.Dv.T. 2190 A-1 bis A-8/Fl".

Yes the FW-190A went thru several engines. The BMW801C is found in the FW-190A thru FW-190A2. The BMW-801D is found in the FW-190A3 thru FW-190A8. The BMW 801D2 recieved several upgrades during it's lifespan including an increase in compression ratio.

The engine operating restrictions were changed throught the lifecycle of the design just as allied engines did as well. All the 801 series radial motors were fuel injected.

Original Engine restrictions are:

1.32ata @ 2400 U/min for 30 minutes (climb and combat power)

1.42ata @ 2700U/min for 3 minutes (emergency power)

The FW-190A5 was "derated" to operate 1.58ata/1.65ata @ 2700U/min for 10-15 minutes IF it was equipped with C3 "emergency power". The C3 system injected fuel directly into the supercharger NOT to burn it in the engine but to use it to keep the heads cool. Same principal as MW-50 and Water injections systems found on LW and Allied Aircraft. It did not actually "boost" the manifold pressure. It just allowed the engine to run at higher power settings for longer periods of time.

Otherwise the FW-190 power restrictions were the same as the Previous FW-190's.

The FW-190A8 was "derated" to operate 1.58ata/1.65ata for 10 minutes WITHOUT any other system installed. Just the basic BMW 801D2.

With the C3 "emergency power" it could operate 1.58/1.65ata "as long as the emergency lasts" or until your fuel ran out. This is why a 115 liter internal auxilary tank is offered as kit in the FW-190A8. A similar 115 liter tank was installed when the FW-190A8 was equipped with GM-1 NOX.
The 115 liter tank was not a popular installment.

Quote

As Crumpp already pointed there was a difference in the fuel injection beween the A5 and the A8, are there other differences in the system as well ?

No as far as I can tell that is the only difference.

You have to purchase the individual FW-190 Flugzeug-Handbuch.

Crumpp

MiloMorai · « **Reply #52 on:** August 15, 2004, 11:40:44 AM »

The BMW 801 engine had 3 cr increases, 6.5 in the early model, to 7.2 in the D model, to 8.3 in the later T models.

MW/ADI/fuel injection was used to STOP pre-ignition which would have destroyed the engine. Pre-ignition would hole pistons and increase temperatures. The primary reason for injection was to stop pre-ignition of the fuel/air mixture. All other reasons were resultant secondary.

The BMW 801 engine used a 2 speed sc not a 2 stage sc.

"High Gear (S) which drove the impellor directly from the crankshaft pinion at a ratio of 7.46:1, while Low Gear (M) was driven via 2 free gears, one if which was clutched, to the impellor at a ratio of 5.07:1. The change-over altitude was set automatically (anoroid switch) at 2500m and there was no way in which the pilot could over-ride the automatic change-over."

from the British report of a 190.

109s were 'derated' from 1.42 to 1.3x, so how can the Fw be derated from 1.58/1.65 to 1.58/1.65? Restricted yes.

sfuchs · « **Reply #53 on:** August 15, 2004, 01:32:25 PM »

Hello Crumpp,

thank you for the quick answer. I'm very interested in the Fw 190, especially the A-Series. I've done some research in the manuals now.

Quote

Originally posted by Crumpp
It should not be used BELOW 1 km.

The Bedienungsvorschrift says clearly "Die erhöhte Notleistung darf nur in Höhen unter 1000 m in äußerster Notlage im Schnellflug entnommen werden." ... that means up to 1 km and not above that height. As far as I know the system was mainly installed in machines which were deployed as Jabos (fighter-bombers).

The flight manual of the Fw 190 A5/A6 (D. (Luft) T. 2190 A5 / A6) reads the same ... "Bei einer Anzahl von Jabo mit BMW 801 D ist eine C3-Kraftstoffzusatzeinspritzanlage vorgesehen, die den Zweck hat, für eine kurze Zeit eine erhöhte Notleistung unter einer Höhe von 1000 m zu erzielen." ... that means a specific C3 fuel injection, that gives for a short period of time an increased ermegency power at heights under 1000 m.

The "increased emergency power" runs the engine at 1,65 ata and is only available at low gear in heights under 1000 m. The figures for 1,58 ata at low gear and 1,65 ata have nothing to do with this system. They are figures for the Fw 190 A7 / A8 / A9 without the useage of "increased emergency power". The flight manual of these subtypes (D. (Luft)T. 2190 A7 bis A9) says that pilots there controlled a small valve with which they could increase the pressure ratio of the engine to 1,58 ata in low gear and 1,65 ata in high gear. They could further increase the pressure ratio to 1,65 ata under 1 km when using "increased emergency power".

- sfuchs -

Crumpp · « **Reply #54 on:** August 15, 2004, 01:47:11 PM »

Quote

Bedienungsvorschrift

Yeah the Bedienungsvorschrift is really confusing as it covers all the 190A series. It is difficult to seperate what applys to what A model. It also does not detail the C3 system. In the Flugzueg-Handbuch it clearly states 1.58/1.65ata for the Fw-190A5. I would be glad to send you the page. Give me you email address and you have send in writing you will not post the information on the internet, publish it, or in anyway violate the Luft-archives copyright.

The Flugzeug-handbuch's cover each one in detail but concentrate more on maintenance and not flying.

Here is some more performance info on the FW-190. Included is an allied wartime translation of the C3 system.

http://www.terra.es/personal2/matias.s/fw190.htm

Crumpp

sfuchs · « **Reply #55 on:** August 15, 2004, 02:08:53 PM »

Hi Crumpp,

thanks for the quick reply and the interesting link. I've got already several manuals from the "Luftfahrt Archiv Hafner" ... the "Bedienungsvorschrift Fw 190 A1 to A8", the "Flugzeughandbuch of the Fw 190 A1", the "Flugzeughandbuch Fw 190 A2 bis A4", the Flugzeughandbuch Fw 190 A5 / A6" and the "Flugzeughandbuch Fw 190 A7 bis A9". The Flugzeughandbücher tell the same as the Bedienungsanleitung as far as I can see ... the Flugzeughandbuch of the Fw 190 A5 (at least my copy, maybe there are different prints) tells only of the 1,65 m under 1000 m ("erhöhte Notleistung") ... the 1,58 ata / 1,65 ata are only mentioned in the Flugzeughandbuch of the Fw 190 A7 to A9 and they are for a completely different and not time-limited system.

- sfuchs -

Crumpp · « **Reply #56 on:** August 15, 2004, 02:41:09 PM »

You are correct. I scanned the manuals. Got over 1000 pages of Luftwaffe material on the 190 now. I assumed it was above and did not catch the jabo only either. It specifically says in the Ohne C3 chapter "For Jager". That explains why you do not see any 1.65 ata charts on the 190A5 and why the 190A8 chart only shows 1.65ata.

And as I said earlier, The FW-190A5 can only run 1.65ata IF it was equipped with C3.

You speak fluent German?

Crumpp

Crumpp · « **Reply #57 on:** August 15, 2004, 02:44:55 PM »

The Motor restrictions as I read them:

FW-190A3

3 min @ 1.42ata

30 min @ 1.32ata

FW-190A5

same as the A-3 when not equipped with C3

With C3 - 10-15 min @1.65ata

FW-190A8

10 min @ 1.65ata

unlimited @ 1.42ata

With C3

"as long as the emergency lasts" @ 1.65ata

niklas · « **Reply #58 on:** August 15, 2004, 04:21:14 PM »

Quote

Originally posted by sfuchs

In the flight manual of the Fw 190 A is written that the "increased emergency power" should only be used in heights up to 1 km. It also states that the engine runs at 1,65 ata and consumes 70 litre of C3 in 5 minutes at "increased emergency power".

The figures posted in this thread show a setting of 1,58 ata for the low gear and 1,65 ata for the high gear - but as far as I understand it shouldn't be used in high gear and the engine should be at 1,65 ata when used (and not 1,58 ata).

Can someone tell more about this ?

- sfuchs -

The increased emergency boost was later cleared from BMW for the high alitutude gear, too (BMW Note from 20.01.44). You have to know the exact dates of the manuals. When they were pre-44 they´ll probably speak about the 1000m limit, even when they mention the A8 project

niklas

sfuchs · « **Reply #59 on:** August 15, 2004, 05:19:18 PM »

@Crumpp
1000 pages about the 190 sounds amazing, I've also collected some material over the last years and find that this forum is a good place to get further information - there is always something more to learn. Yes, I speak fluent german because I'm from germany ... it's quite a bit harder to express myself in english though.

@niklas
The Fw 190 A5/A6 Manual is dated august 1943, the A7 / A9 manual dated march 1944. Interesting fact that the increased emergency boost was later cleared for high gear, too.

- sfuchs -