F4U turn performance, flaps, the real plane, etc (discussion)

[Chalenge]

I don't understand what you mean by this.

The "less draggy" aspect of the wing mount is explained as "the wing root being joined to the fuselage at a ninety degree angle which was the most efficient design for both maximizing strength and minimizing drag".  I'm not sure what you mean by less draggy on one side and more on the other?

Then you need to reconfigure your thinking cap. The F4U wing does not mate with the fuselage at 90 degrees. You can see this clearly in any 3 view of the aircraft. A wing has two sides, top and bottom. The bottom of the wing with respect to the fuselage has a more extreme angle than the top. What they were attempting to approach was similar to a straight wing being mounted to the center of a fuselage. They missed. Furthermore, as the fuselage tapers the angle increases, making the miss even worse. This was always a myth made as a selling point for an aircraft that was never as good as its press. People were hungry for good news and so every claim made by the F4U pilots was accepted. Boyington, for instance, may have scored as few as seven actual kills in his entire career (China included).

I don't know where you dug up the report on the flaps having caused no perceptable change in trim, because the Navy themselves and the Vought test pilot both said it did.

I also read Memorandum #33 for 4 June 1944 in which the Navy tested (combat tested) the F4U1 and F6F3 against the FW190A5. You should read it, too. The 190 they tested outperformed the F4U by their own reports, yet in AH the F4U kicks the 190s butt!

[FLS]

Then you need to reconfigure your thinking cap. The F4U wing does not mate with the fuselage at 90 degrees. You can see this clearly in any 3 view of the aircraft. A wing has two sides, top and bottom. The bottom of the wing with respect to the fuselage has a more extreme angle than the top. What they were attempting to approach was similar to a straight wing being mounted to the center of a fuselage. They missed. Furthermore, as the fuselage tapers the angle increases, making the miss even worse. This was always a myth made as a selling point for an aircraft that was never as good as its press. People were hungry for good news and so every claim made by the F4U pilots was accepted. Boyington, for instance, may have scored as few as seven actual kills in his entire career (China included).

I don't know where you dug up the report on the flaps having caused no perceptable change in trim, because the Navy themselves and the Vought test pilot both said it did.

I also read Memorandum #33 for 4 June 1944 in which the Navy tested (combat tested) the F4U1 and F6F3 against the FW190A5. You should read it, too. The 190 they tested outperformed the F4U by their own reports, yet in AH the F4U kicks the 190s butt!

Do you have a reference for the low drag being a myth? Everythng you've written about it sounds like specualtion.

If you compare the F4U and F6F the difference in the wing attachment angle is obvious. The clear difference is the F4U wing is mounted radial to the center line. Granted it's not precisely radial.

I expect there are other reasons the F6F is slower than the F4U, despite having the same engine and being about the same size, but it makes me wonder about the drag difference. The 0 lift drag coefficient of the F6F is .0211. Anyone know what it is for the F4U?

[mtnman]

Then you need to reconfigure your thinking cap. The F4U wing does not mate with the fuselage at 90 degrees. You can see this clearly in any 3 view of the aircraft. A wing has two sides, top and bottom. The bottom of the wing with respect to the fuselage has a more extreme angle than the top. What they were attempting to approach was similar to a straight wing being mounted to the center of a fuselage. They missed. Furthermore, as the fuselage tapers the angle increases, making the miss even worse. This was always a myth made as a selling point for an aircraft that was never as good as its press.

Yup, I can see that from the drawings I have.  I just pulled that quote out of one of several books that reference that.

Regardless of the angles or geometry, I suppose what really matters is whether or not it gave any advantage at all to the plane.  Did it?  I'm not seeing any tests that spell it out one way or the other, but I could be missing them.

People were hungry for good news and so every claim made by the F4U pilots was accepted. Boyington, for instance, may have scored as few as seven actual kills in his entire career (China included).

Who cares?  I certainly don't, and have never really given a hoot one way or the other when it comes to kill reports.  Are there any pilots (in any plane) where similar claims aren't possible?

I don't know where you dug up the report on the flaps having caused no perceptable change in trim, because the Navy themselves and the Vought test pilot both said it did.

Just out of one of the reports that lyric linked to.  Lots of info in there...

I didn't really dwell on it to tell the truth.  All it means to me is that the speeds the flaps were deployed may have been different in the different tests.  Above a certain speed, I'd expect the nose to raise.  Below a certain speed no amount of flaps will keep the nose from dropping.  At some speed in between isn't it logical to think the trim won't be effected much?

If you'd like, we can dismiss the test claims though.  Let's use the ones you like.

I also read Memorandum #33 for 4 June 1944 in which the Navy tested (combat tested) the F4U1 and F6F3 against the FW190A5. You should read it, too. The 190 they tested outperformed the F4U by their own reports, yet in AH the F4U kicks the 190s butt!

Surely not this report?  Granted, the 190 climbed faster and was faster above 15K...

http://www.wwiiaircraftperformance.org/fw190/ptr-1107.pdf

Here's a snip from it (I did read a good chunk of it, but not all)-



One of the links lyric gave us pits the F4U against several other planes.  P51, P47C, P38G.  The F4U was argued to be "better for close-in fighting" than the P51 and P47, about even with the P38.

Lots of fairly subjective information...

[mtnman]

Honestly, when I really started digging into these reports I was pretty certain I'd find some info to show there were errors in the AH F4U model.  I'm having difficulty identifying them though.

Is it possible we're just on a "witch hunt"?

You know, LOTS of things we think "know" about history don't really appear all that factual under close scrutiny.

At this point, I'm pretty sold on the RL vs. AH pilot being the difference.  In the end, it was man and machine.

In my industry, Overall Equipment Efficiency (OEE) averages out at around 60%.  I.e. it's difficult to find a machine that's able to run at better than 60% of its potential effectiveness.

MUCH of that comes down to the details of how man interacts with machine.  Why would we expect much else when it comes to interaction with a flying machine?  Different variables are at play of course...  In AH, we've eliminated MANY of those variables which the RL pilots weren't able to eliminate.

I don't believe it's reasonable at all to expect that a modern combat pilot can get 100% of the potential effectiveness out of a plane; but they're at a distinct advantage over a WWII pilot.

If we pulled the pilot out of an F4U and replaced him with a computer, or flew it like a drone from the comfort of a chair in a climate-controlled room, how close to AH could we get it to fly?

When I find things like this in flight test reports, it just makes me realize how similar an operator improperly adjusting a machine is to a mechanic improperly adjusting an airplane...  This type of thing lowers the overall effectiveness of the machine, whether it flies or sits on a floor.

This was a "recommendation" that came out of one of the tests...  Really?  Someone thought it would be ok to do this??  How would this practice effect the performance of the plane?

[mtnman]

I haven't seen this video linked before.  It's kind of interesting.

Stalls and spins in WWII planes-

http://www.youtube.com/watch?v=tUs4oC_JiZY

[lyric1]

Hand book I found online.

http://www.scribd.com/doc/55090514/1944-AP-2351A-B-C-D-PN-Pilot-s-Notes-for-Corsair-I-IV-Double-Wasp-R2800-8-or-R2800-8W-Engine

[Zacherof]

Pfft 190in ah will dominate f4 if you know what your doing

[Saxman]

Pfft 190in ah will dominate f4 if you know what your doing

Only if the guy in the F4U doesn't.

Put the top Hog driver vs. the top 190 stick in a duel, and the F4U is going to come out on top more often than not.

None of which is relevant to the subject of the thread. 

[Zacherof]

im just trying to stir the pot 

[Chalenge]

I have been reading the book by Boone Guyton on his time with Chance-Vought. After reading the book it is clear that a great deal of the problems associated with flying aircraft like the F4U have been avoided by choosing to control the aircraft by stick position. It would be easy to get upset by this fact and yell and scream about inaccuracies, but the fact remains that it is impossible to model the limitations of human muscles. Specifically, you will find in the manuals for the F4U the following: "Do Not Spin." It is there because when it concerns the F4U (all models) a left hand spin that goes beyond two turns is always (and I mean always) the final move.

Any spin in AH can be escaped by simply pushing forward. In the real F4U after two left hand turns in a spin you are done. The stick is buried in the pilots crotch and their is not enough human strength in any man to push it forward. The only way to model that is to end every double-left spin as a death-spin.

[Saxman]

I have been reading the book by Boone Guyton on his time with Chance-Vought. After reading the book it is clear that a great deal of the problems associated with flying aircraft like the F4U have been avoided by choosing to control the aircraft by stick position. It would be easy to get upset by this fact and yell and scream about inaccuracies, but the fact remains that it is impossible to model the limitations of human muscles. Specifically, you will find in the manuals for the F4U the following: "Do Not Spin." It is there because when it concerns the F4U (all models) a left hand spin that goes beyond two turns is always (and I mean always) the final move.

Any spin in AH can be escaped by simply pushing forward. In the real F4U after two left hand turns in a spin you are done. The stick is buried in the pilots crotch and their is not enough human strength in any man to push it forward. The only way to model that is to end every double-left spin as a death-spin.

Or it means that the stick forces in the game aren't being modeled properly for all situations.