Author Topic: Aerodynamics websites (Read 1728 times)

Bronk · « **Reply #30 on:** November 21, 2007, 09:40:38 PM »

Quote

Originally posted by Murdr
The "expert" has spoken,

There are good reasons why he was PNGed.

SgtPappy · « **Reply #31 on:** November 21, 2007, 10:19:15 PM »

Sax, I think you're right.

The only problem is, I'm not sure exactly where the information that HTC uses is found. Also, they continue to disprove the 'math behind turning' page.

They state that the extra drag is so huge, you need an equal amount of extra thrust to compensate. Makes sense, but I cannot seem to find any errors in here

If you want to find a quick link to the most recent page of our discussion, it's here

Murdr · « **Reply #32 on:** November 21, 2007, 10:30:57 PM »

Here is a thread you might find very interesting pappy (you might want to work from the most recent pages backwards).

You have to understand that if this is the same guy, he has a habit of selectively ignoring data that disagree with his position, mis-representing data that does, and generally trying to attribute the weight of documentation to what is really his own statements.

SgtPappy · « **Reply #33 on:** November 21, 2007, 11:17:46 PM »

Thanks, Murdr.

That may very well be the same guy.

But if it IS the same guy, he's smarter now as he posted actual proven data in the ww2 a/c forums this time.
The only thing is that his data conflicts with DTango's mathematical equations, and it also conflict with the website link. Too bad he's not able to read all those posts regarding the turn rate of the Corsair in the other forums.

dtango · « **Reply #34 on:** November 22, 2007, 12:25:28 AM »

There was a long long debate in the past about flaps several of us had with Crumpp many moons ago here. From glancing at his posts in the thread you've pointed out he still has not changed his thinking on the topic

. I've and others tried to help him understand the concepts in the past to no avail. I doubt seriously that you'll get further than others have tried here.

BTW His mode of operation is that he'll throw out charts, diagrams, and references which seems to impress some folks. I don't take him too seriously though.

He was PNG'd here for some reason. Don't know the details but if you look at his past posts in here you might get an impression as to why.

Tango, XO
412th FS Braunco Mustangs

Saxman · « **Reply #35 on:** November 22, 2007, 01:14:39 AM »

Maybe someone should start tossing up some links to these conversations. Maybe it won't prove him wrong, but at the very least may humiliate and ostracize him from his new friends.

SgtPappy · « **Reply #36 on:** November 22, 2007, 12:30:17 PM »

Yea, I've seen a few of his posts. Though I'm more inclined to believe you guys and your very impressive links, I feel that I should at least take his posts into some consideration.

To me, this debate is kinda like religion... and many issues for that matter. I have to view all sides and then conclude for my own what I feel is correct.

So far, all the mathematically-proven sites dtango has displayed (in addition to other links others have shown), I'm leaning towards you guys lol.

Murdr · « **Reply #37 on:** November 22, 2007, 06:09:02 PM »

Brooke calculated his data from the calibrated stall speeds, and then compared them to the scale test data. The scale test data was a different flap configuration as he pointed out, and also said "I'll use the values from [F4U], though, as those are for the real, flying, full-scale F4U-1".

Regarding bank angle, don't forget that when you lower flaps, you also lower the speed thresholds for stall conditions. Hence, a higher bank angle can be maintained at lower speeds with flaps deployed in comparison to clean configuration.

It is a given that you will have a higher total drag with flaps deployed in comparison to clean. The question is, at what point do total drag and available thrust reach equalibrium, because that AoA and speed can be maintained without deterioation? Then, how does that comapre with the best sustained rate of turn under clean configuration?

Oh, and actually in the game, while the full flap f4U-4 does have a smaller turn radius than the spit16, the spit16 clean maintains an advantage in turn rate regardless of what the F4U-4 does.

Viking · « **Reply #38 on:** November 22, 2007, 08:36:24 PM »

Yes, very impressive that the F4U and F6F managed in a 1944 test to beat a 1941 model Fw190A-4 with a rough-running engine. And not even a fighter version, but a JaBo version of the 190A-4 (which presumably makes it a 190G originally). I wonder how those US Navy planes would have done against a 190A-6 or A-7 in that early 1944 test.

What I think is impressive is that the three year old 190 managed to out climb both Ami planes and was considered equal in a dive.

dtango · « **Reply #39 on:** November 22, 2007, 08:36:30 PM »

I'm loathe to go posting on another website to get into another debate with crumpp. I can only take so much of trying to patiently reason with someone who it's so nearly impossible to reason with. Reading the posts he's still his same old self as arrogant as ever claiming some higher knowledge than others, spouting out a wall of text with some aerodynamic info yet misapplying what he's saying. He hasn't stated anything most of us aero-geeks don't already know.

For starters thrust also varies with airspeed and increases as airspeed decreases, one of several factors that make assessing sustained turn rate tricky so we can't just make a blanket statement about what increased drag would do in a turn because thrust also increases as airspeeds reduce.

Pappy, my advice is to use this as motivation to study up on aerodynamics

. Spend some time learning and you'll start to see where crumpp could improve on his formal education.

Tango, XO
412th FS Braunco Mustangs

SgtPappy · « **Reply #40 on:** November 24, 2007, 08:27:53 PM »

Thanks, Dtango and all.
I've always been pretty interested in the sector of aerodynamics. I recently borrowed a book on the characteristics of air around wings and the factors contributing to lift co-efficients of airfoils (aerodynamics book in general).

When I find time, I'll be sure to read up on this stuff so as to formulate some of my own reasoning... I'm just not smart enough yet.

Stoney74 · « **Reply #41 on:** November 26, 2007, 12:30:53 AM »

Quote

Originally posted by Murdr
Hence, a higher bank angle can be maintained at lower speeds with flaps deployed in comparison to clean configuration.

You sure about this? I thought the critical AoA was lowered when flaps were deployed? I thought the increased camber and wing area were the reasons for the increased Clmax at the same or less than AoA?

Murdr · « **Reply #42 on:** November 26, 2007, 06:51:52 AM »

Bank angle, angle of roll from wings level. It was mentioned on the other board in regards to level turning.

Stoney74 · « **Reply #43 on:** November 26, 2007, 08:47:27 AM »

Ooops. Sorry, didn't see bank angle--was thinking angle of attack. That's what I get for trying to be Mr. Smarty Pants...