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-   -   HE-111 is a glider (http://forum.fulqrumpublishing.com/showthread.php?t=22872)

kristorf 05-15-2011 03:42 PM

Quote:

Originally Posted by Hunden (Post 283589)
Wow a lot experts and a lot of a## holes here give the guy a break

+1

Sooooo many experts, amazing how many He111 pilots there are still living.

bongodriver 05-15-2011 03:54 PM

col123 is quite right, how did anyone deduce 'big' wings = good gliding performance? every sailplane I know has high aspect ratio long and skinny wings, sounds to me like the 111 has an FM bug if it is gliding so well, those big wings should create huge amounts of induced drag.

Furio 05-15-2011 04:21 PM

Quote:

Originally Posted by bongodriver (Post 283597)
col123 is quite right, how did anyone deduce 'big' wings = good gliding performance? every sailplane I know has high aspect ratio long and skinny wings, sounds to me like the 111 has an FM bug if it is gliding so well, those big wings should create huge amounts of induced drag.

He111 wing is not that “big”. It’s aspect ratio is 5.9, the Bf109 being pretty close at 6.

bongodriver 05-15-2011 05:15 PM

Quote:

Originally Posted by Furio (Post 283598)
He111 wing is not that “big”. It’s aspect ratio is 5.9, the Bf109 being pretty close at 6.

Maybe so, but a typical sailplane aspect ratio is anywhere between 15 to 25 ish and have narrow chord, the 111 has a very wide chord that is what I mean by 'big', by no means a glider wing

jf1981 05-15-2011 05:42 PM

Quote:

Originally Posted by Stanger (Post 283618)
As you see even a casual observation [...]

Stanger, I guess you did not get that post #12 it's been updated with some measurements & some calculation.

Furio 05-15-2011 05:53 PM

Quote:

Originally Posted by bongodriver (Post 283612)
Maybe so, but a typical sailplane aspect ratio is anywhere between 15 to 25 ish and have narrow chord, the 111 has a very wide chord that is what I mean by 'big', by no means a glider wing

You’re right. What I mean is that the He111 has an average aspect ratio for WWII combat types, and this is consistent with an average l:d. Latest tests (edited post ≠ 12) by jf1981 really do show some suspicious numbers. One that looks odd to me is the same l:d at 160 km/h. (where minimum sink is registered) and at 200 km/h. Another is the bad performance of Ju88... Odd.

GnigruH 05-15-2011 08:31 PM

I love how this thread delivered.
I LAUGHED OUT LOUD reading it.
A guy reports something suspicious, then gets bashed a little too hard for not including his test results.
Some 'experts' respond with attitude like: 'you be noob, das game ist flawless', some include deep aero-dynamical evidence like: 'it has big wings, you noob'.
Priceless.

TBH I've seen aeroplanes flying quite good with no wings in this flawless game, nothing is going to surprise me after that.
I bet that after the game becomes playable more ppl will finally realize that fm is a bad joke in many many aspects.

II./JG1_Wilcke 05-16-2011 03:21 PM

Suggested by my CFI, retired Navy Test Pilot, NAWS China Lake.

A good guess for single-engine light (sic...for a twin you have more issues) aircraft is Vx, the best rate of climb speed. But for a better answer:

Flying in calm air, with the engine at idle.

Record your airspeed as and vertical speed vs for at least 3 points - near stall, Vy, Va perhaps. For this purpose, you can just take the ratio of vertical speed to air speed to be L/D.

... Technically you'd need the horizontal component of the airspeed vector, but with realistic errors airspeed will be ok. If you insist, you can correct your airspeed by the factor sqrt( 1- (vs/as)^2 ) assuming of course vs<=as. For as/vs = 2, ( you are descending at 1/2 the airspeed! ) this factor is 0.86 so you can see it's not a big deal.

Given vs in ft/min, as in miles/hour
( mph * 88 = ft/min )

I'll make up some numbers:

VS AS L/D = 88·AS/VS

500 45 7.92

750 90 10.56

1000 110 9.68

If that's still not good enough.. There is a simple formula to create the parabolic approximation f(x) = -ax^2 + bx + c for 3 points... but if you are lazy as I am and/or have more than three points you can use this handy online polynomial regression calculator:

http://www.xuru.org/rt/PR.asp#CopyPaste

Putting in the above numbers, I get f(x) = -a·x2 + b·x + c = -1.273504274·10-3 x2 + 2.097008547·10-1 x + 2.042307692

The best L/D, can be determined by differentiating the above and solving for f'(x) = 0. In general form, I get b/2a, or 82 MPH.

Cool beans.

Any one have a POH for the He-111?

jf1981 05-16-2011 04:51 PM

Hi Wilcke
Could you please add definition of Va, Vx, Vy and POH for me ? Thanks.
I'm not clear with it.

bongodriver 05-16-2011 05:00 PM

Quote:

Originally Posted by jf1981 (Post 284084)
Hi Wilcke
Could you please add definition of Va, Vx, Vy and POH for me ? Thanks.
I'm not clear with it.

Vy= best rate of climb speed

Vx= best angle of climb speed

Va= manouver speed (memory is fuzzy on this but I think it is the maximum speed at which an abrupt control input can be made)

POH= pilots operating handbook (pilots manual)


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