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Re: Aspect ratio.
By:NPenney
Date: 7/8/1998, 2:34 pm
In Response To: Re: Aspect ratio. (Mark Kanzler)

Could be, but I have noticed when you want an F-14 to go really fast you fold the wings back, not out. And when you want to fling it around in hard manuvers, you put the wings out, not back.

Remember, we're not talking about effectiveness as in generating lift or even reducing drag, but in generating a side thrust to shove the end of a boat around. Far different then a wing being used to lift a plane. More akin to the rudder and elevators used to manuever that plane.

> Look up aspect ratio in a good aerodynamics book (Anderson is
> my personal favorite). Structural concerns do limit how high of an
> aspect ratio can be achieved, but a narrow deep rudder will always
> be more effective than a wide shallow rudder (of same airfoil).

> The reason fast nimble planes have short wings is not aerodynamic.
> The moment of inertia causes resistance to sudden rolls (dynamics,
> not aerodynamics). The forces generated during abrupt maneuvers would
> tear off long wings due to increased moments. Transonic flight is
> also hard on structure.

> If engineers could keep a high speed plane together with higher
> aspect ratios it would be one of the greatest performance breakthroughs
> of modern aircraft. By pivoting the wings at the root the higher moment
> of inertia could be overcome.

> Ultimately it comes down to structural concerns that keep us
> from going to higher aspect ratios.

Messages In This Thread

Mayday Mayday! boat goes left
David Walker -- 7/6/1998, 9:17 pm
Re: Try another paddler
Jay Babina -- 7/7/1998, 2:32 pm
Re: Mayday Mayday! boat goes left
Mark Kanzler -- 7/7/1998, 11:51 am
Re: rudders
NPenney -- 7/8/1998, 8:17 am
Re: Aspect ratio.
Mark Kanzler -- 7/8/1998, 11:21 am
Re: Aspect ratio.
NPenney -- 7/8/1998, 2:34 pm
Re: Aspect ratio.
Nick Schade -- 7/8/1998, 3:17 pm
Re: Higher Aspect ratio = No Steering
NPenney -- 7/9/1998, 7:49 am
Re: Higher Aspect ratio = No Steering
Mark Kanzler -- 7/9/1998, 10:38 am
Re: Higher Aspect ratio = No Steering
NPenney -- 7/9/1998, 11:50 am
Re: Old Textbooks, etc.
Mark Kanzler -- 7/11/1998, 12:52 am
Re: Old Textbooks, etc.
NPenney -- 7/10/1998, 2:53 pm
Re: Here's a sketch of one possible solution (as described in prev post)
Mark Kanzler -- 7/8/1998, 12:41 am
Image link still not working.
Mike Spence -- 7/7/1998, 1:28 pm
Re: Image link still not working. (Sorry)
Mark Kanzler -- 7/7/1998, 1:56 pm
Re: Image working.(?)
Mark Kanzler -- 7/8/1998, 1:26 am
Not yet. - Don't despair!
Mike Spence -- 7/8/1998, 1:19 pm
Re: Not yet. - Don't despair!
Mark Kanzler -- 7/8/1998, 2:18 pm
Re: Here it is! (Satisfaction Guaranteed)
Mark Kanzler -- 7/8/1998, 10:23 pm
Re: Here it is! (Satisfaction Guaranteed)
David Walker -- 7/10/1998, 10:28 am
Re: Surfbard skegs.
Mark Kanzler -- 7/10/1998, 11:58 am
Re: Surfbard skegs.
David Walker -- 7/10/1998, 1:49 pm
Re: Surfbard skegs.
David Walker -- 7/10/1998, 5:30 pm
Re: Surfbard skegs.
Mark Kanzler -- 7/12/1998, 11:08 am
Re: Surfbard skegs.
Paul Jacobson -- 7/12/1998, 7:18 pm
Re: Surfbard skegs site (try it again please).
Mark Kanzler -- 7/10/1998, 2:50 pm
Re: Surfbard skegs site (try it again please).
Mike Spence -- 7/10/1998, 6:51 pm
Re: Here it is! (Satisfaction Guaranteed)
Nick Schade -- 7/9/1998, 4:12 pm
Re: Here it is! (Satisfaction Guaranteed)
Mark Kanzler -- 7/11/1998, 12:37 am
Re: Mayday Mayday! boat goes left
Mark Kanzler -- 7/8/1998, 12:39 am
My $0.02
CHad -- 7/7/1998, 11:29 am
P.S.
CHad -- 7/7/1998, 11:56 am
Re: P.S.
Guy Wright -- 7/7/1998, 1:46 pm
Me Too!
Shawn Baker -- 7/8/1998, 11:01 am
Re: Mayday Mayday! boat goes left
NPenney -- 7/7/1998, 7:33 am
how I solved mine.
R. N. Sabolevsky -- 7/6/1998, 11:56 pm
Re: Mayday Mayday! boat goes left
Duane Strosaker -- 7/6/1998, 11:38 pm
Re: Mayday Mayday! boat goes left
Mike Spence -- 7/7/1998, 12:11 pm
Re: Mayday Mayday! boat goes left
Paul Jacobson -- 7/6/1998, 11:20 pm
Off center fins and water flow
David Walker -- 7/8/1998, 5:28 pm
Re: Off center fins and water flow
NPenney -- 7/9/1998, 11:57 am
Re: Off center fins and water flow
Mike Spence -- 7/9/1998, 5:56 pm
Re: Off center fins and water flow
Paul Jacobson -- 7/11/1998, 2:53 am
Re: Off center fins and water flow
Mark Kanzler -- 7/10/1998, 11:47 am
Re: Off center fins and water flow
NPenney -- 7/10/1998, 6:22 am
Re: Skegs and water flow.
Mark Kanzler -- 7/8/1998, 6:10 pm
Re: Skegs and water flow.
David Walker -- 7/8/1998, 6:42 pm
Re: Skegs and water flow.
Mark Kanzler -- 7/8/1998, 7:07 pm
Re: Skegs and water flow.
David Walker -- 7/10/1998, 10:37 am
Re: Skeg attachment w/ silicone.
Mark Kanzler -- 7/10/1998, 11:34 am
Re: Mayday Mayday! boat goes left
Wes Boyd -- 7/6/1998, 10:36 pm