Corsair vs. BF 109G,K or FW 190's

[Soren]

I don`t think it`s intentional, I think they tested what enemy equipment they had in more or less working order. OTOH, if you read the other AFDU 109G test, for example vs the Tempest, it says the pilots of the 109G are 'emberassed by the opening of the slats' in turns - ie. they weren`t pushing the unfamiliar aircraft to it`s true limits in turns. This is reinforced by the fact that if you look at the 190/109/51 result in turns, it says :

the 51 turns better then the 109
the 51 turns about as well as the 190
which means that logically the 190 should outturn the 109... and as per the 3 German tactical evaluations we know, the Soviet etc. testing, and even by simply common sense, this was not the case. All of it points towards the results are caused by British pilots not pressing the aircraft hard enough in turns, this is somewhat of a returning topos with British test, their test pilots backing off from turn ASA the slats are opening, leaving the party when it just gets started.

Exactly Kurfürst, and it was the same for new LW pilots. The British test-pilots weren't used to automatic LE slats, infact they had flown no aircraft featuring it, hence their concerned reaction to the deployment of the slats which would sometimes give a slight notch and a loud bang. I remember reading Handley Page mention he wasn't even contacted during the war by the RAF, despite being the only one in Britain knowledgable about this device. The reason why a few seasoned 109 pilots, including Rall, were reluctant to push past slat deployment was past bad experience with doing so in the 109E which suffered from it slats jamming in turns, one deployed while the other stayed in, pulling the aircraft into a dangerous spin, one which nearly cut Rall's carreer short.

And this is not just reinforced by the German comparative tests as Kurfürst mentions but also comfirmed multiple times by LW Aces explaining the reason why green pilots were afraid of going past slats deployment:


Erwin Leykauf, German fighter pilot, 33 victories
"The Bf 109s also had leading edge slats. When the 109 was flown, advertently or inadvertently, too slow, the slats shot forward out of the wing, sometimes with a loud bang which could be heard above the noise of the engine. Many times the slats coming out frightenened young pilots when they flew the Bf 109 for the first time in combat. One often flew near the stalling speed in combat, not only when flying straight and level but especially when turning and climbing. Sometimes the slats would suddenly fly out with a bang as if one had been hit, especially when one had throttled back to bank steeply. Indeed many fresh young pilots thought they were pulling very tight turns even when the slats were still closed against the wing. For us, the more experienced pilots, real manoeuvring only started when the slats were out. For this reason it is possible to find pilots from that period (1940) who will tell you that the Spitfire turned better than the Bf 109. That is not true. I myself had many dogfights with Spitfires and I could always out-turn them.
One had to enter the turn correctly, then open up the engine. It was a matter of feel. When one noticed the speed becoming critical - the aircraft vibrated - one had to ease up a bit, then pull back again, so that in plan the best turn would have looked like an egg or a horizontal ellipse rather than a circle. In this way one could out-turn the Spitfire - and I shot down six of them doing it."

Walter Wolfrum, German fighter ace. 137 victories.
"Unexperienced pilots hesitated to turn tight, bacause the plane shook violently when the slats deployed. I realised, though, that because of the slats the plane's stalling characteristics were much better than in comparable Allied planes that I got to fly. Even though you may doubt it, I knew the Bf-109 could manouver better in turnfight than LaGG, Yak or even Spitfire."


And then ofcourse comes the fact that aerodynamics supports the above as-well, and I'll get to that in my next post.

[AL Schlageter]

I don't know why people get so hung up on turning circle times. Even a P-47 could out turn a 109 doing a flat turn. Not sure what the maneuver (yo-yo turn?) was called but the P-47 would trade altitude gain for speed loss while turning.

Only about 1/3 of the G-14s produced were of the /AS type. The first appearing in Aug 1944 with some 398 being produced. In July and Aug 1944 some 1527 regular G-14s were produced. Total neabau G-14 was 2689 compared to 1377 G-14/ASs.

American naval fighters (F6F (?) in FAA service off Norway and USN (F6F) off southern France) and came away victorious. Some say the F6F was not as good as the F4U.

[lesofprimus]

U would combat the Hellcat differently than u would the Corsair, using each planes attibutes in ur favor.... Different planes, different tactics...

[drgondog]

Originally Posted by AL Schlageter

I don't know why people get so hung up on turning circle times. Even a P-47 could out turn a 109 doing a flat turn. Not sure what the maneuver (yo-yo turn?) was called but the P-47 would trade altitude gain for speed loss while turning.

Only about 1/3 of the G-14s produced were of the /AS type. The first appearing in Aug 1944 with some 398 being produced. In July and Aug 1944 some 1527 regular G-14s were produced. Total neabau G-14 was 2689 compared to 1377 G-14/ASs.

American naval fighters (F6F (?) in FAA service off Norway and USN (F6F) off southern France) and came away victorious. Some say the F6F was not as good as the F4U.

Al - I don't know about being hung up on the question - more like if a claim is made regarding one performance profile compared between two ships - how do you debate it.

Dan is right, you use what you have, take advantage of any favorable situation, and try to escape the bad one.

At the end of the day the ultimate determinant is which fighter generally prevailed in the fights - but with all of the a/c we have been debating the general performance is close enough that the victor had positive tactical situation and pilot skill.

Regards,

Bill

[delcyros]

Does we know how the F4U´s airframe was composed off? What material at which thickness was used as skin for:

-underbelly(fuselage)
-underbelly (engine)
-wingroots lower side
-wings upperside
-wingtips
-tail leading edge
-tail
-fuselage

I know that the F4U had lot´s of armour installed. Does soemone know where exactly?
Even if this tends to appear secondary, I think it has some relevance here with the 20mm mine rounds in mind, the germans used. The F4U commonly is understood to be one of the ruggest single engined A/C to see widespread service and with the datas above I could make some approximations free from personal opinions as how sensible the airframe would be to different scenarios of battle damage.

Thanks in advance,
delc

[renrich]

The armor on the F4U consisted of: a .109 inch hardened aluminum alloy plate above the gas tank in front of the pilot, a large piece of armor plate weighing 53 pounds directly behind the pilot, bullet resistant plexiglass in front of the pilot, a removeable quarter inch steel plate could be placed beneath the pilot's seat. The gas tank and gas lines were self sealing. The wing internal tanks in the F4U1 were not protected but those tanks were deleted later in the war. Also early Corsairs had an additional piece of armor in front of the oil tank in the engine compartment. I have a complete description of the structural details but can't type that much except to say that the wing center section comprised mainly one huge casting that contributed much to the Corsair's robustness.

[Juha]

"The British test-pilots weren't used to automatic LE slats, infact they had flown no aircraft featuring it, "

Soren, are you sure on that, for example very early Westland Whirlwinds had LE slats.

[FLYBOYJ]

Originally Posted by Juha

"The British test-pilots weren't used to automatic LE slats, infact they had flown no aircraft featuring it, "

Soren, are you sure on that, for example very early Westland Whirlwinds had LE slats.

Yep - that's like saying a pilot had difficulty flying an aircraft because the landing gear handle was on the left side of the cockpit instead of the right....

[AL Schlageter]

Originally Posted by Juha

"The British test-pilots weren't used to automatic LE slats, infact they had flown no aircraft featuring it, "

Soren, are you sure on that, for example very early Westland Whirlwinds had LE slats.

All Whirlwinds had le slats but had them locked closed after an accident.

The Swordfish had le slats on its upper wing.

[Glider]

I have heard this claim about the 109 slats only being used by the experienced pilots because new pilots were scared or nervous of the slats deployment.

My question is this. The Germans were many things in the war but they were not stupid. It would be very easy to train the new pilots to 'fly' through the deployment of the slats. They even had the Me108 to use as the perfect trainer, even with the Me109, a couple of follow my leader flights would suffice.
So why didn't they unless the benefits are less than thought?

Another thought
Its also worth remembering that the 109 was at its best in a slow turning fight and the slat deployment is the result of a slow speed combat, something no experienced P51 pilot would follow. Therefore the main difference could well be the old favourite, an experienced pilot in a 109 will always have an advantage over an inexperienced pilot in a P51

[drgondog]

Originally Posted by delcyros

Does we know how the F4U´s airframe was composed off? What material at which thickness was used as skin for:

-underbelly(fuselage)
-underbelly (engine)
-wingroots lower side
-wings upperside
-wingtips
-tail leading edge
-tail
-fuselage

I know that the F4U had lot´s of armour installed. Does soemone know where exactly?
Even if this tends to appear secondary, I think it has some relevance here with the 20mm mine rounds in mind, the germans used. The F4U commonly is understood to be one of the ruggest single engined A/C to see widespread service and with the datas above I could make some approximations free from personal opinions as how sensible the airframe would be to different scenarios of battle damage.

Thanks in advance,
delc

Delc - unless someone has detailed drawings for each assy or installation on the F4U you would be hard pressed to get what you need.

In general the thickness of the aluminum skin would depend on the following criteria:

1.) Am I trying to take bending loads and transfer them to shear in the panels to redistribute the loads
2.) Do I want flush or button rivets for the application - this would have considerable influence on edge distance and thickness of rivets between the two.
3.) What are the buckling considerations.

I have read that certain aircraft like a Me 109 which had to be more innovative in wing design to accomodate a main spar at 40+ percent chord versus 25+ % for most a/c had to create more of a 'torque box effect'..

one way of creating a stronger torque box is to increase the thickness of the skin (top and bottom) to not only enhance rigitidy of the box but also effectively increase the top and bottom 'cap area' for the spars..

I suspect w/o proof that most of the F4U was .032 to .040 2024 for surface skin and that the spars were designed to take bending loads in the wing more or less independent of additional torque box effects - and suspect you could use those thicknesses to calculate blast effects

[renrich]

My reference says that the wing leading edge torque boxes had metal skins of .091 inches thickness. The fuselage made use of large metal skin sheets and employed spot welding to a great extent. The largest skin sheet was pre formed and measured 43 by 102 inches. Fuselage skins were up to .072 inches thick. Interestingly the left and right horizontal stabilizers were identical and were interchangeble.

[drgondog]

Originally Posted by renrich

My reference says that the wing leading edge torque boxes had metal skins of .091 inches thickness. The fuselage made use of large metal skin sheets and employed spot welding to a great extent. The largest skin sheet was pre formed and measured 43 by 102 inches. Fuselage skins were up to .072 inches thick. Interestingly the left and right horizontal stabilizers were identical and were interchangeble.

I don't doubt your info, but would comment that keeping skin below .050 as much as possible is as much about weight of rivets as anything else. Thicker skins are generally for heavy bending applications

Leading edge torque box would probably be limited to .091 just for sheer ability to form an airfoil nose section w/o cracking.

Does your source state the type of 'skin' being welded (ie. steel or 6064 aluminum?

[Soren]

LoL, guys just because the whirlwind had slats doesn't mean the test pilots were used to or trusted them, esp. considering the fact that one crashed because of slat malfunction (Like 109E) and all production a/c after that had the slats shut against the wing in flight - just one more reason for British test pilots to be vary about the LE slats on the 109. And then ofcourse its not even sure that the test pilot flying the 109 ever flew a Whirlwind.

"While Handley-Page slats were fitted to the outer wings, the production aircraft flew with them locked shut, since at least one crash of the test aircraft was attributable to slat failure."

There's also a reason why experienced LW aces and test-pilots mention the same concern about slat deployment amongst fresh LW pilots.

Later in the war new LW pilots were taught not to be afraid of the slats deploying and that the fun was only beginning when they deployed, which is why you wont find any pilots from this point on saying they had any trouble against the Spitfire in maneuvering flight. Infact you've even got a British Spitfire pilot [Pierre Closterman] admitting that the Spitfire was inferior in turn performance compared to the Bf-109 at slow speed.

Yep - that's like saying a pilot had difficulty flying an aircraft because the landing gear handle was on the left side of the cockpit instead of the right....

You've got to be kidding me FLYBOYJ.. Automatic LE slats were not a std. addition on WW2 a/c, esp. not British a/c, comparing this device to placing a handle on the right instead of the left is just plain ridiculous.

Claiming that British test pilots had no reason for concern and weren't is also just plain ridiculous, esp. considering the comments actually made by British pilots and also esp. when considering that Westland had the slats shut in flight because they were afraid of the slats jamming, expressing the exact same concern as any test pilot would, infact it was most surely a test pilots who had adviced Westland to have them shut in flight in the first place.



"The 109 being embarrased by the opening of its slots" This doesn't exactly indicate that the pilot was pushing past slat deployment, infact the only thing it clearly points to is that he wasn't even attempting to do so and abandoned the maneuver entirely.

[renrich]

Bill, the skin of the fuselage was aluminum that was spot welded. The skin on the torque boxes refers to the wing center section and they seem to be aluminum, but not specified and the wing outer panels seem to have had the same skin on the leading edge. The wing tips were plastic and the British ones were different from the American.