Bf-109 vs Spitfire vs Fw-190 vs P-51

[Soren]

double post

 

[Soren]

Bill it's impossible to change your mind anyway nomatter the amount of fact one brings to the table, so why don't we just agree to disagree on the subject. Encounter reports provide a horrible method for measuring comparing a/c anyhow.

If we want ot compare the a/c accurately we will use the specs avaialble to us.

I can tell you the following though Bill, at the same power rating it took the Fw-190 A-8 430 m to clear the runway, compared to the 295m for the Ta-152H. That's a pretty clear indication of the difference in maneuvering performance between the two a/c.

Take off distances time is often a good indicator of sustained maneuvering performance.


Now keep in mind that a heavy Fw-190 Jabo (Not even a fighter like the A-8) turns just as well as the Tempest.

There should be no doubt in anyones mind after that..

 

[drgondog]

Ever heard of the feather which became 10 Chickens ?

From mouth to mouth stories tend to change

Just out of curiosity since I haven't read his book, did he write it in 1945 when the memories could be expected to be very fresh, or 40 years later or 50 years afterwards.

If you've ever been in an auto accident, say 40 years ago - can you remember what happened just before and just after?

Just Curious.

 

[Soren]

Soren - have you dismissed from your mind the issues discussed and documented about 190 issue with losing tip control due to elastic deformations in High G turns?

Dismissed ?? Bill the the 190 didnr't loose tip control as such, a larger part of the wing just stalled. But regardless plenty of warning prior to this happening was always given. Now if you ignored the stall warning (Slight buffeting and notching of stick) then the a/c would stall and rather violently so since the lift distribution was fully elliptical in turns by virture of aerelasticity and the NACA 23000 itself already was known for its nasty stalling characteristics. (And this is directly from Gene!)

Are you saying that I lie about that, or Gene lies about that or Lednicer lied about that?

Nope, you just haven't understood it apparently (Or you forgot ??), but Gene does.

As to 'thrust' documentation? This may be interesting.

Are you referring to Horsepower and Horsepower to weight ratios as 'Thrust'??

Is that what you are saying?

I am talking about actual thrust developed in KG!

Its on the Fw-190 Ta-152 drag table I already have posted on this forum before...



Finally Bill, before we get into anymore of this pissing match crap, I've already acknowledged that you're not clueless, but you admitted yourself that some things needed freshing up, which I understand. Also note that when I said you were clueless you had prior to that called me a bonehead, now what would you expect anyone to respond after that ??

Respect Bill, respect is the key.

 

[drgondog]

Bill it's impossible to change your mind anyway nomatter the amount of fact one brings to the table, so why don't we just agree to disagree on the subject. Encounter reports provide a horrible method for measuring comparing a/c anyhow.

I have to agree- kinda said that all along as you trot out irrefutable personal anecdotes and i trot out the opposite perspectives from similar sources.

If we want ot compare the a/c accurately we will use the specs avaialble to us.

Ah, yes. Specs, performance charts and calculations from fact based data in tests.

I can tell you the following though Bill, at the same power rating it took the Fw-190 A-8 430 m to clear the runway, compared to the 295m for the Ta-152H. That's a pretty clear indication of the difference in maneuvering performance between the two a/c.

Nah, not really. Look at the the J3 Cub and compare the power rating required to take off in a 35 knot wind against say a P-51 or the Ta 152. I might be able to take off with the engine idling.

Take off distances time is often a good indicator of sustained maneuvering performance.

As noted above, there are interesting data but that isn't going to get you to the promised land.


Now keep in mind that a heavy Fw-190 Jabo (Not even a fighter like the A-8) turns just as well as the Tempest.

There should be no doubt in anyones mind after that..

Soren, there is much doubt about claims not based on material fact. I am real sure you don't know much about aero but I do believe you are intelligent.

I have given you the approach to balance Forces, all the factors you need to get the correct forces, the assumptions you have to be careful of, to be able to actually do the types of charts Gene did for you. Further, if you use what I showed you today you can navigate through the math and get 'reasonable approximations.

You know what you will find? - based on aero and math - not your view of the world - is that all of these a/c are pretty close in most manuevers, that because of the nature of reciprocating engines, the approximations of 'near compressibility effects' to props, airframe elasticity, drag rise, etc that you will have a reasonable 'rule of thumb' for the difeerences in 'saw tooth' altitude performance -

and that NONE of these a/c is 'superior' in every way.

But when you get into debates with other guys on this forum - why don't you stick to facts and the math behind the facts for your statements, and when you aren't sure of a Performance claim - simply say "i'm not sure - but I'll try to figure it out and get back with you". Gene can explain VERY well what you need to know to be consistent and reasonable with respect to assumptions

What I asked you to do above in getting to Thrust, Bank Angle and Velocity at That Bank angle - is a late second year homework problem in undergrad Aero...and in the third year you will go from Subsonic to transonic/supersonic complications dealing with swept wing, asymmetrical load effects, compressibility, aerodynamic moment effects to manuevering, etc. - then on to stability and control, aeroelasticity and other specialized studies.

You will learn about stuff you have been using to browbeat others on the forum in your first semester. Having said that, you know more than most on the forum because they may not be interested in really understanding aero.

In other words, it IS complicated.

 

[drgondog]

Dismissed ?? Bill the the 190 didnr't loose tip control as such, a larger part of the wing just stalled. But regardless plenty of warning prior to this happening was always given. Now if you ignored the stall warning (Slight buffeting and notching of stick) then the a/c would stall and rather violently so since the lift distribution was fully elliptical in turns by virture of aerelasticity and the NACA 23000 itself already was known for its nasty stalling characteristics. (And this is directly from Gene!)

Check with Gene again - you did miss it-again. The outboard section stalled too fast because the tip region deformed under load and reached CLmax at same time inbord region was stalling with higher relative AoA. If the twist of the 190 wing had not stopped at 81.5% of span - and contiued to twist it probably would not have stalled like that.. in other words under those circumstyances, the buffeting and aileron loss occurred at about the same time in High G, but NOT during low G level flight as in landing



Nope, you just haven't understood it apparently (Or you forgot ??), but Gene does.

Lol.. yes, once again, I didn't 'apparently understand'.

I am talking about actual thrust developed in KG!

Its on the Fw-190 Ta-152 drag table I already have posted on this forum before...

I have no idea 'where' and 'before' means as a reference. Her and now is the Post in question

Finally Bill, before we get into anymore of this pissing match crap, I've already acknowledged that you're not clueless, but you admitted yourself that some things needed freshing up, which I understand.

Ah, from the master, a little pat on the head. thank you so much Soren for intimating that I am not clueless. You understanding that I needed to brush up helps me get through my humiliation - at least a little bit.

Also note that when I said you were clueless you had prior to that called me a bonehead, now what would you expect anyone to respond after that ??

Respect Bill, respect is the key.

Soren, you called me, and a multitude of others 'clueless long before I called you a bonehead. That reaction on my part should have been kept under restraint but this was about the time you told me I was 'clearly clueless' regarding interpreting the lednicer Report regarding Suction (versus Drag)

As to respect - if one were to search this forum for the amount of derogatory phrases you have used to others who disagree with you - in contrast to my own indiscretions - I suspect the ratio will be FAR higher than the alleged Ta 152H air to air ratio - but that is speculation not a fact.

I tend to the ironic and occsaionally sarcastic - which I still have to guard against.

Back to the Thread - Post your Thrust values and tell us wher you got them from.

 

[renrich]

Firstly Bada, I don't know what you mean by addressing me as "my dear," but if you are a woman, please continue but if you are a man, please refrain from that as where I come from, that would be an insult. Secondly, I probably know as much about LW fighter armament as you. I know that many were armed with cannon and many also were armed with 30 cal mgs as well. I also know that the later war LW fighters carried heavier and heavier armament in order to shootdown big bombers which could take a lot of damage. The cannon would probably be at a disadvantage against a fighter with 6-50 cals because of a slower rate of fire, less range and a worse trajectory plus a smaller ammo load(less rounds) No question that a hit by 30 mm cannon would handle another fighter much of the time. But the hit probability from 6 or 8- 50s would be much greater and a few 50 cal rounds can do a lot of damage. Obviously, you also don't know what I am talking about when I mention deflection shooting. It has little to do with all around visibility but rather visibility directly over the nose. A US Navy test of the FW190 states that deflection shooting by that AC would be difficult because of poor visibility straight ahead. The TA would even be worse. The book I am quoting from has the FW section and BF section contributed by a Robert Grinsell and he gives eleven references for the FW section, all but one is German. In the whole book with 12 sections about WW2 AC, I have found the performance figures to jibe nicely with other sources. Who is to say that your's or Soren's sources are more accurate? That is the reason that I have to temper my opinions with operational results rather than go only with numbers from goodness only knows where. Soren, let me see now. You state that the TA could takeoff in 295 meters. I believe that would be about 900 feet. There is no US Navy fighter in WW2 that can't better that. The F4U4 could do it in 630 feet. That is with full internal fuel, full ammo, hard surface, zero wind, sea level and take off power. I believe your exact statement is "that is shorter than ANY Spitfire, 109, F4U or 190 model." Is all your data as accurate as that? Once again, may I ask how many air to air kills the TA had, how many ground strafing kills it had, how many tons of bombs and rockets it dispensed, how many successful bomber missions it escorted, what was it's availablity per centage for a mission, what was it's kill record against P51, P47, P38 or F4U, how many sorties did TAs fly, how many TAs actually were operational, how many successful carrier landings and takeoffs did it execute.

 

[Hunter368]

As to respect - if one were to search this forum for the amount of derogatory phrases you have used to others who disagree with you - in contrast to my own indiscretions - I suspect the ratio will be FAR higher than the alleged Ta 152H air to air ratio - but that is speculation not a fact.

I tend to the ironic and occsaionally sarcastic - which I still have to guard against.

 

[Soren]

Ah, yes. Specs, performance charts and calculations from fact based data in tests.

Which is exactly what we're doing.

W for example have to have the Cd0 Cl figures from real tests, all of which we have for most of the a/c (We lack the Fw190 P-51's Cd0 figure)

Beyond that we need thrust figures, and to be dead on precise the 'e' figures, but the 'e' figures undoubtedly differ no more than .05 between all these a/c (109, spitfire, 152, 190, -51)

Nah, not really. Look at the the J3 Cub and compare the power rating required to take off in a 35 knot wind against say a P-51 or the Ta 152. I might be able to take off with the engine idling

All figures are at std. zero wind conditions Bill, and the Ta-152H takes off at 295m while the Fw-190 A-8 takes off at 430m. Again like I said, a pretty clear indication of the difference in maneuvering performance.

 

[Soren]

Renrich,

The performance data I presented on the Ta-152 is more accurate for the reason that it is based on actual original documents and is from a book specifically about this a/c and written by an expert on the subject, Dietmar Hermann.

Now as to the F4U-4's take off distance, where the heck did you get 630 ft from ?? The best I could find was 790 ft off the deck of a carrier in "calm" weather.

PS: At Take off Power the F4U-4 even has 2,100 BHP available.

 

[drgondog]

Which is exactly what we're doing.

W for example have to have the Cd0 Cl figures from real tests, all of which we have for most of the a/c (We lack the Fw190 P-51's Cd0 figure)

I believe the Cdwet, as referenced by lednicer for all four ships is correct for the Parasite Drag.. the .0053 for the real 51B airframe set up with instrumentation, towed to 25,000 by a P-61, was a result of dive tests by NAA to validate Ames Wind tunnel tests for both full scale and 1/6 scale

Beyond that we need thrust figures, and to be dead on precise the 'e' figures, but the 'e' figures undoubtedly differ no more than .05 between all these a/c (109, spitfire, 152, 190, -51)

All figures are at std. zero wind conditions Bill, and the Ta-152H takes off at 295m while the Fw-190 A-8 takes off at 430m. Again like I said, a pretty clear indication of the difference in maneuvering performance.

You are about to try to prove it? Correct

Yes - you need the Thrust figures and now you know how to calculate them from the Speed versus Hp by Altitude Test Charts - as I described above.

And dead on 'precise' for e is not a huge factor between the 190D and 51 but the tip to chord ration might hurt the Ta 152 slightly - maybe all of 1-2 percent. The Spit should be the best based on planform, but because of the greater AR of the Ta 152 it probably is better - I haven't done the math but guess the Ta 152 probably the best and 51B the worst on 'e', and by far the best on Cdwet.

Remember Cdo is frequently referred to as the zero lift Drag Coefficient for that specific airfoil section and Cdwet is the calculated zero Lift Cd for the Wing, plus the wing body and includes nascent drag (like a 109 wheel well), friction, profile drag (flat plate), etc)-

in other words Cd wet in Lednicer is all Parasite Drag - zero lift - and separate from Induced Drag.

I have seen references, which I believe are used incorrectly, using Cdo as the entire Parasite Drag (everything but the Induced drag)

 

[drgondog]

Renrich,

The performance data I presented on the Ta-152 is more accurate for the reason that it is based on actual original documents and is from a book specifically about this a/c and written by an expert on the subject, Dietmar Hermann.

Mike Williams references Hermann also... could there be something on the Williams site that is fair and balanced?

 

[Soren]

I believe the Oswald Efficiency factor for the different wings to be the following:

Spitfire: .85
Bf-109F,G K: .82
Fw-190: .84
Ta-152H: .83
P-51: .83

What do you think about that Bill ??

And we have the Clmax figures already:

Bf-109F,G K: 1.70
Ta-152H: 1.62
Fw-190: 1.58
Spitfire: 1.36
P-51: 1.35

Now as for Cd0, well we have Spitfire 109's which is:

Bf-109K: ~0.021
Spitfire: 0.0229
Bf-109G: 0.023

Now the P-51 Fw-190 undoubtedly have lower Cd0 figures. Now tell me if you think I'm terribly off Bill but would I be wrong in your mind to presume that the P-51 has a Cd0 of 0.0168 and the Fw190 one of 0.0185 ??

 

[Soren]

Mike Williams references Hermann also... could there be something on the Williams site that is fair and balanced?

The problem with Mike Williams is that he is extremely selective about what he puts out on his website and he generally completely disregards the higher performance charts out there. Another problem is that Williams doesn't have a lot of knowledge on German a/c. He just recently acquired himself a performance chart for the Fw-190 A-8 - I have them all, and have so for a loooong time..

Anyway lets not argue over this, lets stick to the topic.

 

[Soren]

Bill I didn't start calling you names, that was you, plz go back and read the thread.

Now you can't blame me for getting abit thrown off by you calling me a bonehead, now can you ? Honestly it was that very comment which pissed my off beyond what I have ever been on this forum. In short I despise namecalling

Ah, from the master, a little pat on the head. thank you so much Soren for intimating that I am not clueless. You understanding that I needed to brush up helps me get through my humiliation - at least a little bit.

Bill let me put it like this then: You know more within aerodynamics than I, you've recieved an education within its various fields, and so while I have only covered some of them you have covered most of them - which is plenty more than me.

However even the best of us forget things as time passes by, and you needed something freshened up, no big deal I experience the same, you showed that in the suction debate where I confused things.

Now what do you say, shall we get on with the topic ?

 

[DerAdlerIstGelandet]

Bill I didn't start calling you names, that was you, plz go back and read the thread.

Soren he is talking about the way you talk to anyone who disagrees with you...

 

[Soren]

Oh god let's not get into that again... talk about a dead horse..

 

[renrich]

Soren, data on takeoff distance is from Dean, "America's Hundred Thousand, " and he states the table is from USAAF and US Navy wartime references. I won't copy entire list but these are examples: The F4U4 was at 12281 pounds, F4U1D-12289 pounds-840 feet, F6F5-12483 pounds-780 feet, P47D25-14411 [pounds-2540 feet, P51D-10176 pounds-1185 feet. Dean states that by VJ day 370 P51H models had been produced. I don't know if any saw combat. I don't believe that takeoff distance is a good measure of maneuverability. For instance the F4F3A at 7320 pounds could get off in 650 feet. The F4U4 beat it at 630 feet but no one could claim the F4U could outmaneuver a F4F3A.

 

[DerAdlerIstGelandet]

Oh god let's not get into that again... talk about a dead horse..

I am not starting anything. I was only explaining what needed to be explained...8)

 

[Soren]

Renrich the figures aren't right though, I have the original POH for all a/c in question. And the P-51D needed 1,400 ft atleast.

The Fw-190A-8 P-51D are about the same in terms of take off distance, while the Dora's is shorter. The Spitfire 109 are also comparable, the 109's being slightly shorter. But the Ta-152H beats them all.

Now as for the F4U-4 possibly having a shorter take off run with full flaps (It had some bloody large flaps!) I wouldn't be surprise if it needed slightly less room to take off.

However the point is that the Ta-152H was perfectly carrier capable, and more so than the 109 Spitfire and much more so than the Fw-190, P-51 P-47.