FW 190A Questions

[Fencer51]

I have a few questions concerning the FW190, I would appreciate any help available.

1.  How does the FW 190A-5 performance differ from the A-2,  A-3 and A-4.

2.  Could the A-5 be substituted for the early A models without being an overwelming force against Spitfire Mk Vs?

Thanks in advance.

[Krusty]

The A-5 has a slightly more powerful and more reliable engine. [EDIT: Technically it's the same engine, but I think it had a higher boost rating]

It's almost the same engine, but the earlier models had teething troubles, and overheating problems. I'd "guess" that if we had an A-3 or an A-4 in this game, it would be rated lower than the A-5. Also they moved the engine forward to help the center of gravity and cooling with the A-5, so I'm guessing the A-3/A-4 might have had stability issues (worse stalls?)

Pure speculation, though.

[TUXC]

Krusty's right about the early 190s having cooling issues. I believe one test pilot described his feet feeling as if they were in a furnace when he was flying the 190. As far as I know there were no stability issues with the earlier ones and I think moving the engine forward was in anticipation of future weight increases to maintain the c.g. and also to help with engine and cockpit cooling.

In terms of what would matter in the game (since engine problems aren't modelled), the earlier 190s are all somewhat slower (max speed 390-400mph) than the A-5 due to the lower maximum boost ratings of the engines. On the other hand, they are all somewhat lighter and so they turn a little better at lower speeds while still having great high speed maneuverability as all 190s do.

The Spit 5 is going to be outclassed by any 190 so it really doesn't matter if you sub in the A-5 for an A-4 or A-3. The 190 could do everything better than the Spit 5 except flat turn, and could break of combat at will due to superior climb, dive, acceleration, and speed.

http://www.odyssey.dircon.co.uk/VBv190.htm

The Spit 9 and 12 were both made to counter the 190 by mating more powerful engines to the Spit 5 airframe.

[DiabloTX]

Originally posted by Krusty
The A-5 has a slightly more powerful and more reliable engine. [EDIT: Technically it's the same engine, but I think it had a higher boost rating]

It's almost the same engine, but the earlier models had teething troubles, and overheating problems. I'd "guess" that if we had an A-3 or an A-4 in this game, it would be rated lower than the A-5. Also they moved the engine forward to help the center of gravity and cooling with the A-5, so I'm guessing the A-3/A-4 might have had stability issues (worse stalls?)

Pure speculation, though.

Correct, and the 6-inch engine move was to improve both CG and vibration issues.  The cockpit heat issues were more or less resolved with the A-1's but the engine overheating problems were almost completely cured with the A-2's.  I think the moving of the engine for CG issues would alter handling but by how much I don't know.

A-1's and -2's had the 801C rated at 1600hp but some did leave the assembly lines with the 801D-1 and -2 rated at 1700hp but being 600 lbs. heavier and reducing range by about 100 miles.  But the top speed was increased by 20 - 40 mph.

[Krusty]

The first unit to see major combat use was the A-3, though, which had the same engine

Cooling problems weren't sufficiently solved til the A-5, as there were still problems with the rear row of cylinders and the airflow. The nose extension allowed changes with the air ducting (more room to work with it, I guess)

[DiabloTX]

A-2's introduced the cooling slots on the fuselage forward side panels which were then retro-fitted to the A-1's.  As far as I've been able to research, this considerably reduced the overheating as a problem.

[Denniss]

The 801C was rated at 1560 PS (not hp) at sea level, the often cited 1600 PS are available at  900 m altitude. Similar stuff with the D-2, 1700 PS at sea level and 1730 PS at  600 m.

The 801D-2 made the A-3 different from the A-2, the A-2 had the older 801C engine.

[joeblogs]

I was under the impression that occured in the prototypes before the A-3 went into production.

Afterall, the 190 was actually designed around a different engine, which did not develop sufficient horsepower. When the opted for the BMW801, they lengthened the nose and were forced to add some area to the wing.

-Blogs

Originally posted by DiabloTX
Correct, and the 6-inch engine move was to improve both CG and vibration issues.  The cockpit heat issues were more or less resolved with the A-1's but the engine overheating problems were almost completely cured with the A-2's.  I think the moving of the engine for CG issues would alter handling but by how much I don't know.

A-1's and -2's had the 801C rated at 1600hp but some did leave the assembly lines with the 801D-1 and -2 rated at 1700hp but being 600 lbs. heavier and reducing range by about 100 miles.  But the top speed was increased by 20 - 40 mph.

[Krusty]

The wing size did not change. They lengthened the nose eventually, but not at first (note the A-3, A-4, and A-5 all have the same engine, but the nose is moved forward only on the A-5 (and after) )

[Knegel]

Originally posted by Denniss
The 801C was rated at 1560 PS (not hp) at sea level, the often cited 1600 PS are available at  900 m altitude. Similar stuff with the D-2, 1700 PS at sea level and 1730 PS at  600 m.

The 801D-2 made the A-3 different from the A-2, the A-2 had the older 801C engine.

Hi,

the BMW801D-2 is listed with 1800PS sea level and 1820PS @ 800m.

The 1700/1730PS is the power with a setting which use the RAM effect to increase the FTH at highspeed, while the max power decrease, while this setting probably dont had to be used.

In an power curve(in english) both powers are included, they  write, to smaler max power curve(higher FTH) :
"Engine power, allowing for dynamic air presure gain at equivalent level speeds."

This sounds to me that both powersettings was available somehow. The FTH for max climb is in 800m(fth 1st curve, 1820PS), while the Vmax is in 1400m(fth for the 2nd curve, 1730PS).

To the initial questions:

1. The A5 had a very similar weight like the A3, if both did use the same number of guns. The A5 was just 50kg more heavy. So with the much better engine the A5 must have been better than the A3.

2. If we see the R/L experiences between the powerless 190A3 vs the SpitVb, where the 190A3 could do all better but sustained turns, our A5 is not to good vs our SpitV.

Greetings,

Knegel

[gripen]

The BMW 801D-2 output chart (Sh. Nr. 9-801.5401 dated 10.7.1942) contains two curves for given power setting, one gives static output in the test stand and other gives out put at high speed including loses due to intake system. Normally the Fw 190 took air from inside engine cowling ie the intake air was allready heated a bit by the cooling fan and the engine (there was possibility for external intakes which reduced the power loss due to heating of the intake air and increased the FTH but also added some drag).

[Denniss]

Originally posted by gripen
The BMW 801D-2 output chart (Sh. Nr. 9-801.5401 dated 10.7.1942) contains two curves for given power setting, one gives static output in the test stand and other gives out put at high speed including loses due to intake system. Normally the Fw 190 took air from inside engine cowling ie the intake air was allready heated a bit by the cooling fan and the engine (there was possibility for external intakes which reduced the power loss due to heating of the intake air and increased the FTH but also added some drag).

I know this chart. But the original chart contains a part "N(PS) = N(Luftschraube)+ N(Lüfter)", translateable as N(PS) = N(propeller) + N(cooling fan). It looks like this chart displays engine power without subtracting the power needed to operate the cooling fan.

Fw 190 A-5/A-6 manual speaks of 1730 PS available from 600 m altitude but without RAM effect (ohne Staudruck).

[gripen]

Originally posted by Denniss
I know this chart. But the original chart contains a part "N(PS) = N(Luftschraube)+ N(Lüfter)", translateable as N(PS) = N(propeller) + N(cooling fan). It looks like this chart displays engine power without subtracting the power needed to operate the cooling fan.

Fw 190 A-5/A-6 manual speaks of 1730 PS available from 600 m altitude but without RAM effect (ohne Staudruck).

I have the original as well but I errorneously understood the description wrong. That makes difficult to use that chart for analysis. I wonder how they actually measured the rammed output then because the fan affects intake temperature and output (rammed output might be a calculation). I have some RAE measurements on the Fw 190 and Do 217 cooling fans and 70ps for the fan seems to be quite close (test data shows 45-71 hp at ground level and 2450 rpm for the fan from the Fw 190 depending on speed and some other variables).

[joeblogs]

From William Green's Warplanes of the 3rd Reich, pp. 195-97

The initial prototyp flew with a BMW 139 18 cylinder enginge. The initial wing was 161 square feet in area.

It was decided to replace this with the BMW 801, adding about 350 lbs to weight. The air frame had to be re-stressed and the cockpit pushed back.

After some initial tests, the designers realized the wing loading was too high and designed a new wing of 197 square feet in area. This is the wing that went into production.

-Blogs

Originally posted by Krusty
The wing size did not change. They lengthened the nose eventually, but not at first (note the A-3, A-4, and A-5 all have the same engine, but the nose is moved forward only on the A-5 (and after) )

[Krusty]

In production variants, the wing size did not change