Which is better: P-47 or Fw-190?

[lesofprimus]

Great stuff, but i dont really see how this applies to the -47 vs. the -190...

[DAVIDICUS]

Cheddar Cheese raised the issue of a head to head match between the FW-190D-9 and the P-47N. Because no reliable climb data appears available for the "N" model, the "M" and "J" data was referenced which gave rise to a side discussion on the reliability of the "M" data.

[lesofprimus]

I followed that much... But why is the initial climb data so topically important?? Thats just a small part of what the combat would evolve into...

[DAVIDICUS]

Well Les, it could have been about armament, dive speed, roll rate, (you get the idea) or any of a host of other specific attributes that end up being hashed about on this forum that individually make up only a small part of what combat involves.

So in response to your question, and a response I might add that you have probably given your kid on more than one occasion, "Just because." :P

[Soren]

I said , " ... or otherwise become effective starting at 30K." I followed that up with the example that at 25K feet it was making a difference.

I wasnt talking the -47 alone, but the difference between the -47 and the Spit XIV. At 25,000ft the Spit XIV still climbs noticably better.

I just took a look at your data on the Mk. XIV. The climb rate at 1,700ft was 5,110fpm for 18.3 lbs of boost (remember there was the potential for 25lbs of boost which represents a 38% increase over 18lbs.).

According to this doucment on the production model the climb rate was 4650-4700ft/min with 18lbs boost, which was the max allowable boost: http://www.spitfireperformance.com/spit14climbchart.jpg

With 25lbs boost, the max initial climb rate would likely have risen to 5200ft/min. (I don't know where you get 38% increase from)

In any case, 20,000ft was reached in 5.1min during that test, and with 25lbs boost it would most likely reach this in 4.9min.

Can we agree that the -47M would never reach 20,000ft in 4.75min ?

Even the Spit 21 couldnt reach 20,000ft in under 5.2min, or 5min at best.

I speculated that the maximum initial climb rate of the P-47M at War Emergency Power might be as high as 4,500fpm which is 600 fpm less than the Mk. XIV utilizing just 18.3lbs of boost.

I could go along with 4,000 ft/min for the -47M as a max, but it would slow down very quickly, much more quickly than the Spit XIV.

I also speculated that the climb rate for the heavier "N" might initially be around 3,500fpm (near the rate of the Fw-190D-9).

I speculate the -47N's climb rate to be around 3,150ft/min, but I could go along with 3,500ft/min souly because of its sheer starting speed, however it would slow down REAL quick.

Why don't we just throw in the towel and agree to disagree Soren.

Lets see if we can't agree to agree with the above first

[GrayWard]

Did anyone read the excellent article in the winter 2005 "Flight Journal" on German fighters that discussed a comparison of a FW190A-4 against a F6F-3 and F4U-1D. They compared rate of climb, horizontal speed, horizontal acceleration, rate of role, maneuverability, stability and control, angle of vision, general characteristics in mock combat and armament.This was done in 1944 with a captured 190. It gives a good indication of how it would stand against the P47. It was thought using the right tactics the American fighters would come out on top.

Gray.

[Soren]

Originally Posted by GrayWard

Did anyone read the excellent article in the winter 2005 "Flight Journal" on German fighters that discussed a comparison of a FW190A-4 against a F6F-3 and F4U-1D. They compared rate of climb, horizontal speed, horizontal acceleration, rate of role, maneuverability, stability and control, angle of vision, general characteristics in mock combat and armament.This was done in 1944 with a captured 190. It gives a good indication of how it would stand against the P47. It was thought using the right tactics the American fighters would come out on top.

Gray.

Yeah I read it.

You can read here aswell: http://www.geocities.com/slakergmb/id88.htm

[marseille jr]

for escort duties I'd mount a p47 (range, dive, armor)
for dogfights a dora (or a ta-152) would be the byrd of preference here (cannons, more nimble, climb)

[DAVIDICUS]

"According to this doucment on the production model the climb rate was 4650-4700ft/min with 18lbs boost, which was the max allowable boost"

Yes, well I thought you would prefer the document that you cited. Just as I prefer the "M" data that I cited over that which you cited. Your data states 5,110fpm at 18.3lbs of boost at 1,700ft. http://www.spitfireperformance.com/jf319.html
Are you now claiming that your data, which we have been arguing about, should not be trusted? Is there any other data or figures that you would like to withdraw at this time?


25 is 38% more than 18. An increase in boost from 18lbs to 25lbs represents an increase in boost of 38%. I still find it hard to believe that such an increase would shave only 12 seconds off the entire climb almost four miles up to 20K feet. Think about that for a second (or twelve). You yourself said that going to 25lbs from 18lbs would mean a difference of 4.9 minutes as opposed to 5.1 minutes in a climb to 20K (that's 12 seconds).

You also said, "With 25lbs of boost, the Spit XIV's max initial climb rate was 5,040ft/min, and it would according to tests reach 20,000ft in 4.9min with this amount." Where did this come from? The Mk. XIV data I presented only was for 18lbs of boost and indicated an initial climb rate of 4,700fpm. Your data, on the other hand, indicated 5,110 ft/min for just 18.3lbs as opposed to 25lbs of boost. Where did you get the 5,040fpm at 25lbs of boost figure from?

Earlier you estimated the "M" model's initial climb to be 3,500fpm. Now we're at 4,000fpm. You also estimated the initial climb of the XP-47J (the 504mph, 46,000ft ceiling fighter) to be but 3,900fpm.

At high altitude, the Spitfire doesn't have the advantage of P-47's turbosupercharger. That's why the P-47 was such a hot ship at high altitude. I don't really know how the climb performance between the Mk. XIV and "M" model would compare from say 30K to 40K ft. Perhaps fuel for another discussion.

I sense you are coming around, albeit slowly. If we go around for another 16 pages of posts I'm sure I can convince you but I think we've beat this one into the ground.

[DAVIDICUS]

Thanks for posting the link Soren. I haven't read it.

So it really indicated that using the right tactics the P-47 would come out on top?

Interesting. Do you agree Soren?

[lesofprimus]

So in response to your question, and a response I might add that you have probably given your kid on more than one occasion, "Just because."
_________________

OK, Ill buy that for a Dollar...

[Sal Monella]

I bet you're a good lawyer. What kind of law do you do?

[FLYBOYJ]

Soren, Davidicus, got a question for both of you.....

In your discussions, you guys keep talking about "boost" assuming you mean supercharger boost measured in inches of mercury at the intake manifold, and then relating this to climb perfomance. Are you gathering this data from flight manuals? I could tell you that at a given desired "boost" or manifold pressure you also have to consider RPM which is controlled by propeller setting, not the throttle. Comments?

[Soren]

Yes, well I thought you would prefer the document that you cited. Just as I prefer the "M" data that I cited over that which you cited. Your data states 5,110fpm at 18.3lbs of boost at 1,700ft. http://www.spitfireperformance.com/jf319.html
Are you now claiming that your data, which we have been arguing about, should not be trusted? Is there any other data or figures that you would like to withdraw at this time?

Lets keep this friendly shall we ?

If you read my posts more properly you will not missunderstand them so much, here's what I said:
According to this doucment on the production model the climb rate was 4650-4700ft/min with 18lbs boost, which was the max allowable boost: http://www.spitfireperformance.com/spit14climbchart.jpg

The 5,110fpm at 18.3lbs of boost at 1,700ft figure, is for the prototype.

25 is 38% more than 18. An increase in boost from 18lbs to 25lbs represents an increase in boost of 38%. I still find it hard to believe that such an increase would shave only 12 seconds off the entire climb almost four miles up to 20K feet. Think about that for a second (or twelve). You yourself said that going to 25lbs from 18lbs would mean a difference of 4.9 minutes as opposed to 5.1 minutes in a climb to 20K (that's 12 seconds).

Which is pretty much, DAVID. The 18lbs boost only lasted 5min

You also said, "With 25lbs of boost, the Spit XIV's max initial climb rate was 5,040ft/min, and it would according to tests reach 20,000ft in 4.9min with this amount."

I was still talking the production model.

Earlier you estimated the "M" model's initial climb to be 3,500fpm. Now we're at 4,000fpm.

Don't put words into my mouth DAVID ! I said I speculated it to be 3,500ft/min, but I was willing go up to 4,000ft/min to satisfy you DAVID. I still think 3,500ft/min is the most reasonable number.

You also estimated the initial climb of the XP-47J (the 504mph, 46,000ft ceiling fighter) to be but 3,900fpm.

Which it most likely was, it wasnt 4,900ft/min for sure, thats faster than a Bf-109K-4.

DAVID this whole arguement started with me objecting to your crazy 20,000ft in 4.15min/4.75min figure, but somhow we got it twisted to initial climb rate. All im 'really' concerned about is the 20,000ft time.

At high altitude, the Spitfire doesn't have the advantage of P-47's turbosupercharger. That's why the P-47 was such a hot ship at high altitude.

True, and I never denied that. But at 25K feet the Spit XIV still climbs faster, as its powerloading and wingloading still gives it the edge.

I don't really know how the climb performance between the Mk. XIV and "M" model would compare from say 30K to 40K ft. Perhaps fuel for another discussion.

At that altitude the P-47 is superior, also in the climb I would suspect.

I sense you are coming around, albeit slowly.

Not really, Im just tired of this discussion and want it finished. But hey, lets rock !

If we go around for another 16 pages of posts I'm sure I can convince you but I think we've beat this one into the ground.

[Soren]

Originally Posted by DAVIDICUS

Thanks for posting the link Soren. I haven't read it.

No problem.

Originally Posted by DAVIDICUS

So it really indicated that using the right tactics the P-47 would come out on top?

Interesting. Do you agree Soren?

Against the Fw-190A-4, definitely.