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Old 11-14-2018, 07:28 PM   #61
Shahdoh
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Here is the next round of testing with the mustang going slower. I wanted to use some established power settings so I used "Cruise - Max" setting with 20 degrees of flaps (2 notches) that gave me 180 mph instead. I felt those numbers provided a better baseline for stability of the test then a real low manifold pressure setting. I then did the test at the same cruise setting without flaps, getting the mustang to a midrange speed of nearly 280 mph.

Results were similar, though the slower the speed, the more pronounced the induced drag was, but not by much.

I also ran some quick and dirty tests with the 109 and 190. I have not flown those as much so I just used a low to midrange power setting. Even still, could see similar results due to slip drag.

https://www.twitch.tv/videos/335869562
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Old 11-14-2018, 08:11 PM   #62
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Originally Posted by Shahdoh View Post

Results were similar, though the slower the speed, the more pronounced the induced drag was, but not by much.

It's actually more a case of parasite drag here, with the added contribution, among other elements, by the fuselage...
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Old 11-14-2018, 10:43 PM   #63
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Thanks for the correction. I used the term induced in the manner that I had introduced it by causing the slip with the rudder trim. Research on the term "induced drag" shows that is has a different meaning (that part of the drag on an airfoil that arises from the development of lift) and that I miss used the term. My apologies for any confusion it may have caused.
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Old 11-15-2018, 07:51 AM   #64
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Quote:
Originally Posted by Shahdoh View Post
Thanks for the correction. I used the term induced in the manner that I had introduced it by causing the slip with the rudder trim. Research on the term "induced drag" shows that is has a different meaning (that part of the drag on an airfoil that arises from the development of lift) and that I miss used the term. My apologies for any confusion it may have caused.
No problem at all, alas, being Portuguese I would naturally use "induced" too and we have "induzido" here as something caused by...

But I did know about that "official" definition in the domain of aerodynamics, so, I decided to suggest the correction.

What matters is that your and others posts have been important in bringing this subject to discussion - sideslip effects as modelled in DCS prop aircraft.
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Old 11-15-2018, 09:41 AM   #65
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Quote:
Originally Posted by Shahdoh View Post
Thanks for the correction. I used the term induced in the manner that I had introduced it by causing the slip with the rudder trim. Research on the term "induced drag" shows that is has a different meaning (that part of the drag on an airfoil that arises from the development of lift) and that I miss used the term. My apologies for any confusion it may have caused.
Interesting that "induced" in your case was not a mistake. Sideslip generates side force or "lift" that generates induced drag giving the main part of resulting drag. This side force gives side acceleration moving the ball.
So, remembering that induced drag is proportional to lift^2...
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Old 11-15-2018, 11:23 AM   #66
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Thanks Yo-Yo.

Back to the issue at hand though, how accurate are the effects of drag displayed in the tests for the prop aircraft in DCS.

Last edited by Shahdoh; 11-15-2018 at 11:26 AM.
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Old 11-15-2018, 01:45 PM   #67
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Quote:
Originally Posted by Yo-Yo View Post
Interesting that "induced" in your case was not a mistake. Sideslip generates side force or "lift" that generates induced drag giving the main part of resulting drag. This side force gives side acceleration moving the ball.
So, remembering that induced drag is proportional to lift^2...
Touché :-)
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Last edited by jcomm; 11-15-2018 at 01:56 PM.
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