fw 190a5 flight model

[Gaston]

Originally Posted by FC99

Structural limit for deformation is the one listed in manual, for fighter planes, safety factor was typically about 1.5 so plane with 8G limit will be expected to survive 12G. Between 8 and 12G plane will suffer permanent damage and in case of repeated over-stressing it will break even at values under 12G.
You can see in attachment where is the expected wing failure for one WWII fighter.

"Between 8 and 12G plane will suffer permanent damage"

Well, I figure in typical WWII aircraft the upper limit is 6 G (typical pilot limit) plus 2 Gs of engine-caused wing bending... So that is still 8 Gs total, and still within what you say is the start of permanent deformation...

An exceptional case is the P-51, which with G-suit could make the pilot tolerate 7 Gs, and probably added 2 "Gs" or more with the engine leverage...

So that makes for 9-10Gs... Hey, isn't the P-51 well-known for unexpected -and never explained- wing and tail failures? Hmmm... What a coincidence...

Also the P-51's wing obviously bent more than expected given its gun reliability record under turning Gs: Now isn't that another interesting coincidence?

Another interesting case is the Spitfire, which in my view must have added an exceptional amount of wing bending to its 6 G pilot limit: I figure up to 3 Gs, or over 22 000 lbs worth of extra wing bending over the "base" 44 000 lbs at 6 Gs...

This also makes for a total of 9 Gs, but the mutliple spar-inside-the spar wing construction was well-designed to bend, and could probably take that without huge risks... Unlike the P-51, the Spitfire is not known for wing failures, but IS known for wing deformation at high Gs with careless pilots... What a coincidence...

Since the pilot could not take much more than 6 Gs without at least losing his situational awareness in close combat, it does seem a bit strange these things were often damaged...

Gaston

[Gaston]

Sorry for the long delay, but re-reading all those P-47Ds accounts is a large "investment" of my time, and you'll understand I have other things to do than to convince people...

I'll just post part of the long rambling post I prepeared, and yes there will be P-47 accounts to debate...

I did find TWO account of Me-109Gs causing some trouble in turns to a P-47, both by the same P-47 pilot, Covelle.

They are sustained turns, but they are hardly a show of crushing Me-109 superiority... That they are both from the same pilot, out of hundreds of accounts of P-47s beating Me-109s in typically 2-3 turns, is hardly convincing, not to mention the content of the reports.

Rare, rare, RARE case of the Me-109G causing the P-47 trouble in a Luftberry: Only one of two I am aware of so far...:

http://www.wwiiaircraftperformance.o...er-11feb44.jpg

Another rare case of a P-47 in trouble vs a Me-109, by Covelle again, despite him having no trouble with his tanks full previously, now had trouble with one out 109 out of several (but equal to the others): Then, out of ammunition and still fighting(!): "I broke into this 109 and he tacked on to me, but I managed to out-turn him until I reached the clouds":

http://www.wwiiaircraftperformance.o...le-7june44.jpg


Note this, however, before the nay-sayers start singing in the streets over these two accounts...:

I have no doubt a reduced-power ME-109G will out-turn a full power paddle-blade P-47D, especially a Bubbletop and especially to the right...

So I'll get back to those later...

With that out of the way, let's try once again to inject a bit of observed FW-190A reality into this... (And I will spell it this way...)

Tactical and technical trends, Nov. 5-11 1942:

-"Maneuverability--Except at lower speeds-around 140 MPH(!)- The FW-190 is superior and will out-turn the P-38" (A FW-190A-4)

-1943 British test: "The P-38G and FW-190A-4 are roughly similar in turning ability"


Note this combat of a P-38G against a Me-109G:

Lt. Royal Madden from the 370th FG, 9th AF, July 31, 1944

“Approximately 15 Me 109s came down on Blue Flight and we broke left. I then made a vertical right turn and observed Blue Two below and close and Blue Four was ahead and slightly above me. I glanced behind me and saw four Me 109s closing on my tail fast and within range so I broke left and down in a Split S. I used flaps to get out and pulled up and to the left. I then noticed a single Me 109 on my tail and hit the deck in a sharp spiral.

We seemed to be the only two planes around so we proceeded to mix it up in a good old-fashioned dogfight at about 1000 feet. This boy was good and he had me plenty worried as he sat on my tail for about five minutes, but I managed to keep him from getting any deflection. I was using maneuvering flaps often and finally got inside of him. I gave him a short burst at 60 degrees, but saw I was slightly short so I took about 2 radii lead at about 150 yards and gave him a good long burst. There were strikes on the cockpit and all over the ship and the canopy came off. He rolled over on his back and seemed out of control so I closed in and was about to give him a burst at 0 deflection when he bailed out at 800 feet.

Having lost the squadron I hit the deck for home. Upon landing I learned that my two 500 pound bombs had not released when I had tried to jettison them upon being jumped. As a result I carried them throughout the fight.” [!!!!]

Well Ok it is all meningless etc...

Anyway, here are a few P-47 combat reports with my comments:

-Poor FW-190A high-speed handling (400 MPH speed, elongated loop, abrupt pitching-up, blacking out the pilot as in the "tendency to black-out the pilot" in the P-47 test two links above (nose high deceleration in a broad curve of course), snapping completely out in 400mph turns etc...):

http://www.spitfireperformance...0-murrell-2dec44.jpg

Inability of the FW-190A to make turns at 500 mph: "He tried short sharp turns right and left, and what seemed skidding turns down. There was no violent evasive action at all.":

http://www.wwiiaircraftperformance.o...l-2march44.jpg

Superior P-47D turn rate against Me-109G (contrast later to FW-190A):

http://www.wwiiaircraftperform.../56-mudge-1dec43.jpg

http://www.wwiiaircraftperform...-covelle-19may44.jpg

Lesser or nil P-47D superiority in turns to right vs Me-109G (as example of why the opposite could be demonstrated: It seems the P-47D out-turned the Me-109G severely to the left mostly):

http://www.wwiiaircraftperform...truluck-27sept43.jpg

Now contrast this to the FW-190A-8, late in 1944 (The P-47 has to escape in a zoom...):

http://www.wwiiaircraftperformance.o...ke-19dec44.jpg

More Me-109G turnfight-beating links

http://www.wwiiaircraftperform...cdermott-25may44.jpg

http://www.wwiiaircraftperform...8-luckey-19may44.jpg

http://www.wwiiaircraftperform...-covelle-19may44.jpg

http://www.wwiiaircraftperformance.o...rth-7oct44.jpg

"I easily out-turned them (2 Me-109Gs) from 9000 ft to 2000 ft":

http://www.wwiiaircraftperformance.o...-15march44.jpg

"We started turning with several 109s, and were having no difficulty doing it at 23500 ft. with full tanks"

"About 4 (109s)across the circle from and five pulling in on us from six o'clock. But as we pulled deflection on the others across from us, the rest seemed to lose interest in the fight and disappeared"

10 000 ft.: "The e/a started trying to turn, and we out-turned them immediately"

http://www.wwiiaircraftperformance.o...le-19may44.jpg

Earlier needle-tip prop (pre-Jan-1944) P-47Ds also showed a significant superiority in sustained turns to the Me-109G, except that to the right the margin is closer: "My excess speed was about gone but I was gradually getting inside and nearer to him" ---Despite being in a right-turning Luftberry: Close to stalling but still gaining...:

http://www.wwiiaircraftperformance.o...ke-19dec44.jpg

Luftberry

http://www.wwiiaircraftperformance.o...e-8april44.jpg

Turning`

http://www.wwiiaircraftperformance.o...-22feb44-b.jpg

two turns around hangar and "I was continually out-turning him"

http://www.wwiiaircraftperformance.o...t-8april44.jpg

two luftberrys. I closed on the last E/A

http://www.wwiiaircraftperformance.o...tz-29nov44.jpg


"tight luftberry. My excess airspeed was about gone, but I was gradually getting inside and nearer to him (Me-109)"

http://www.wwiiaircraftperformance.o...k-27sept43.jpg

"In this engagement we succeeded in out-diving and out-turning the enemy (Me-109) at any altitude"

http://www.wwiiaircraftperformance.o...on-12may44.jpg

8000 ft-"We had no difficulty turning and climbing with them":

http://www.wwiiaircraftperformance.o...ey-19may44.jpg

In another example, which I could not find, a gondola Me-109G holds its own to the right with a P-47D at high altitude. (Altitude seem to matter little in relative P-47D vs Me-109G turn performance)

In another example of P-47D turn assymetry vs the Me-109G, notice how, against the very same Me-109G, the contest is a LOT longer and closer when to the RIGHT (several P-47 pilot quotes confirm the strong preference of the P-47D for the left turn)...:


http://www.wwiiaircraftperform...wilkinson-1dec43.jpg

Interesting mixture of turning and dive/zooming by a FW-190A: I would call it an unusually equitable use of both turning and dive and zoom: He gets killed in a zoom:

http://www.wwiiaircraftperformance.o...-23march44.jpg

Against a late FW-190A-8, no so easy...: "We fought a long running and turning fight eastward, during which which I was out-turned several times which necessitated climbing and allowing the e/a to run" Just before that a Luftberry alone with 3 Me-109s had resulted in a kill...

http://www.wwiiaircraftperformance.o...ke-19dec44.jpg

Against the FW-190A? Not so easy...:

Again, long turning battle with the FW-190A, a rough match:

http://www.wwiiaircraftperformance.o...-22april44.jpg


Again,"not being able to hold any more deflection" against a FW-190A:


http://www.wwiiaircraftperformance.o...l-8march44.jpg

"Not being able to tighten my turn any further" against a FW-190A, and "overrunnning" him twice in the same sentence:

http://www.wwiiaircraftperformance.o...l-8march44.jpg

Now... For a fair comparison, wouldn't you agree a first step would be similar amount of combat accounts showing the "superior turn-fighting" Me-109Gs out-turning the poor helpless P-47? (And this at low speeds in sustained multiple circles, I might add, since high speeds did seem to favour the Me-109G vs the P-47 at least a little...)

Very noteworthy in these accounts is that altitude seems to matter little when the Me-109 goes up against a P-47: On the deck, very high, pretty much the same...

I collated this from a larger post, sorry if there are repetitions...

I imagined all of it anyway you know...

Gaston

[MaxGunz]

Originally Posted by Gaston

I imagined all of it anyway you know...

Gaston

All of it? Even the parts you took to misuse from history? Nahh, you take too much credit, you only added your own completely infallible interpretation.

Why, those aerp-engineers and scientists... all they know is some numbers, not the truth while you alone are able to adjust things back. They are just ignorant children compared to your dazzling insight. For example, they don't even know what "stress risers" are, and they invented the term! The Fools!

[MaxGunz]

Originally Posted by Gaston

First of all it is not 13 or 14 Gs, but 6-7 Gs plus 3 "Gs" worth of bending: So 9-10 Gs of structural load at most.

Really? Or did you just pull that out of your ear? Because the people who did the actual testing got higher values without guessing at all. They tested the structures to the breaking point.

(It would explain some unexpected breakage and, interestingly enough, the failure of the P-51s guns to work properly despite likely ground wing-bending testing...

Interestingly enough the failure of different ammo feeds to have failed under turning G's was known and written into the very histories you claim to have encyclopedic knowledge of.

They never tested those guns in actual turning flight,

Never? Anywhere? Not like you can't remember or find but actually never?

and, as a result, the P-51's gun jams under G load were always triple that of the P-47: Going from 500 mrbf in early '44, to around 1000 in 1945, while the P-47 went from 1500 in early '44 to 3000 + in 1945... The improvements might have been in part due to lower late-war altitudes for both types)

That and actually changing the ammo feed on the P-51. They had to do a change in the gear doors too and a whole list of fixes.

In any case, those Gs are for the airframe's wing bending value, not Gs that the pilot actually feels, or are you just pretending?

Gaston

First of all, you should learn about human G testing and G's. It's not just the G's, it's how long you are *at* the G's.

* Go through disturbed air and your plane maybe shakes, that is momentary G force. At higher speed the shake is more. In fact there are actual reference maximum speeds for flying in such conditions because you can break the airplane especially if you also try and maneuver in such conditions, like trying a hard pullout while buffeting.

As for cantilever wings, they are made to flex a certain amount, it's part of the design. It beats breaking. But even short-term G's can overload the wings, they do not fail the same way that humans do.

Watch a pilot pull 11.2 G's in the Red Bull Air Races.

[K_Freddie]

The race is on.....

[Treetop64]

...as an outsider looking in to an interesting discussion, Gaston, you might wanna consider giving up. You're equivocally arguing over semantics, to no constructive end, just for the sake of salvaging and continuing an argument.

It's not working.

[Gaston]

It is not pointless, because now after a few years of looking for wing-bending data, I realize wing bending measurements were not done in turning flight for WWII fighters: I am told by those who know that the -apparently- rare times during which wing bending data is gathered in flight, it is done by dive pull-outs only...

Would the P-51 have had jamming guns at three times the normal rate, particularly in turning battles, if they had done these tests?

As for the challenge I was issued by Glider, the ratio of P-47s out-turning Me-109s vs the opposite is pretty telling: I am sure Glider will have great trouble matching even one tenth of the P-47/109 outcomes I presented above...

Or one third for the dive and zooms vs multiple consecutive 360s examples...

So much for a great theoretical advantage...


I also wanted to adress the claim of violation of physical laws:

Imagine a situation where you have in each hand a pulley system that multiplies your pulling force by 100.

Imagine each system is connected to opposite extremities of a steel bar: Leaning back you pull say 50 lbs in each hand: 5000 lbs of pulling force at the other end of each pulley system.

If you alternately vary the force in each hand, would the steel bar offer any resistance to your moving it back and forth? Does no perceptible resistance mean the steel bar is not being pulled apart by 10 000 lbs of force?

This is what is called a violation of physical laws here...

My claim is that two large forces cancel each other out: One force is the resistance of the propeller to a curving trajectory, which I figure is around 100 lbs for each degree of angle of attack -hardly an outlandish figure...

The other force is a deformation of the void above the wing, which is linked to the above: This force has to be proportionately much greater because of a very unfavourable leverage relationship to the nose, where the prop is.

So the deformation of the void above the wing is the equivalent of having a much larger "pulley force multiplier" within the wing, faced at the other end by a much longer "lever" in the nose, both cancelling each other out proportionately as the AoA increases.

And, like the steel bar, the wing will know those extra forces are there, but won't really show much if you don't measure bending...



Of course, on a nose-pulled aircraft, for the two "extra" forces to be balanced, the CL must move in front of the CG (in addition to becoming greater in force), or the pilot would feel an extra effort in the stick to lean back the prop, which he clearly doesn't...

The forward displacement of the CL might seem to involve a significant effort*: But the CL is made of air, wind tunnels do not replicate a curving trajectory, and they do not replicate an object being held in the air entirely by the speed of its propulsion from the nose...

Or you can cling to the notion that the Me-109G out-turns P-47s...

Gaston

*I think the faster "outside turn" air leaks from the bottom of the wing, from the trailing edge, maybe a long way forward into the upper wing area, in any case gradually increasing and deforming the void above the wing, as well moving the CL forward, as the AoA increases. That would explain the larger lift forces which the greater they "increase", the more they demonstrate the wastage incurred from the nose leverage: That waste from the nose leverage increases the less the CL moves forward, because the CL moving forward is the wing's own opposing lever, and the less lever it has the more the upper wing void will deepen.

Hence the deeper the void above the wing, the less the CL has moved forward of CG...

[Igo kyu]

There is no suction, there is only pressure.

[jameson]

A.S. I am surprised that you think that Me109 was capable in the turning combat. There is general opinion that BF109 was rather average when it comes to combat with many manuevers. It`s very common opinion that BF109G with its technical and tactical characteristics was rather "hunter" then turnfighter..

I.K. Lies! Me109 was exceptional in turning combat. If there is a fighter plane built for turning combat , it has to be Messer! Speedy, maneuverable,(especially in vertical) and extremely dynamic. I can`t tell about all other things, but taking under consideration what i said above, Messerschmitt was ideal for dogfight. But for some reason majority of german pilots didn`t like turn fight, till this day i don`t know why.
I don`t know what was stopping them, but it`s definitely not the plane. I know that for a fact. I remember battle of Kursk where german aces were starting "roller-coaster" rides where our heads were about to come off from rotation.
No, seriously... Is it true it`s a common thing now that Messer wasn`t maneuverable?

A.S. Yes.

I.K. Heh.. Why would people come up with something like this... It was maneuverable...by god it was.

From here:
http://forums.ubi.com/showthread.php...-soviet-pilot?

[JtD]

You still haven't answered Gliders challenge. I know you think you do, but you actually haven't. It's your task to simply pick one combat report you like. Nothing more. Not to post a dozen or so selected examples.