Author Topic: So can you go downwind faster than windspeed?  (Read 3810 times)

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Offline Inigo Montoya

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So can you go downwind faster than windspeed?
« on: July 06, 2010, 01:31:01 PM »

Offline wannabridin

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Re: So can you go downwind faster than windspeed?
« Reply #1 on: July 06, 2010, 01:48:39 PM »
pretty freaking cool!  the visuals help clear up what exactly people were arguing about...  nice find!
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Offline Bob Wessner

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Re: So can you go downwind faster than windspeed?
« Reply #2 on: July 06, 2010, 01:51:14 PM »
Yeah, but it doesn't answer the really big question, can a plane take off on a conveyer belt?   ::) :)
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Offline Inigo Montoya

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Re: So can you go downwind faster than windspeed?
« Reply #3 on: July 06, 2010, 02:07:33 PM »
bob...shut up! ;D  I thought you knew better than that! :D

Offline KeithTurk

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Re: So can you go downwind faster than windspeed?
« Reply #4 on: July 06, 2010, 02:11:49 PM »
Well....ahhh No .... unless the belt has some associated devices to create drag,  then the air passing below the plane would have it's own wind speed.... which would allow the aircraft to lift off the belt once the wind speed exceeded it's minimum take off speed.

Now the next question.... if your flying forward at 200mph and fire rockets.... will the 400mph rocket be going 600mph or 400mph?

Offline gmonkey

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Re: So can you go downwind faster than windspeed?
« Reply #5 on: July 06, 2010, 07:26:58 PM »
Now the next question.... if your flying forward at 200mph and fire rockets.... will the 400mph rocket be going 600mph or 400mph?

Depends on whether or not you're in a vacuum.
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Offline tramp

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Re: So can you go downwind faster than windspeed?
« Reply #6 on: July 07, 2010, 01:14:26 PM »
OMG
i had hoped that we were done with this kind of thread
my head still hurts from the others
the rocket would still travel at 400mph
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Offline Gordon

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Re: So can you go downwind faster than windspeed?
« Reply #7 on: July 07, 2010, 01:22:14 PM »
He ruined all the fun by posting the answer right in the first post! ;D

Offline MCRider

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Re: So can you go downwind faster than windspeed?
« Reply #8 on: July 07, 2010, 02:22:35 PM »
I was under the impression that iceboats did that all along? according to this article they do. No news here.

Scroll to the bottom.

http://www.iceboat.org/faqiceboat.html
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Offline KeithTurk

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Re: So can you go downwind faster than windspeed?
« Reply #9 on: July 07, 2010, 05:05:11 PM »
actually it would fly at it's maximum velocity for the propellant it had available  and would use significantly less Fuel to get to speed so it's top speed would likely be significantly higher then 400 but most likely well less then 600 as the Aero loading would go up radically with increased speeds...

Fun stuff if your in that business...

Offline Gordon

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Re: So can you go downwind faster than windspeed?
« Reply #10 on: July 07, 2010, 05:15:22 PM »
If you're pissing into a 50mph headwind, how hard do you have to push to keep from getting your pants wet, and what injuries will you incur from pushing so hard? 

Offline KeithTurk

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Re: So can you go downwind faster than windspeed?
« Reply #11 on: July 07, 2010, 05:25:26 PM »
Shoot that one is easy Gordon......  not hard at all.... Simply point it UP!!!

Offline Gordon

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Re: So can you go downwind faster than windspeed?
« Reply #12 on: July 07, 2010, 05:29:00 PM »
Shoot that one is easy Gordon......  not hard at all.... Simply point it UP!!!

Don't forget to close your mouth! :-X

Offline KeithTurk

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Re: So can you go downwind faster than windspeed?
« Reply #13 on: July 07, 2010, 05:49:36 PM »
Ya ThhiiinK??

Offline wannabridin

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Re: So can you go downwind faster than windspeed?
« Reply #14 on: July 08, 2010, 08:40:58 AM »
if a man speaks deep in a forest, and there's no woman there to hear him, is he still wrong??   ;D
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Offline KeithTurk

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Re: So can you go downwind faster than windspeed?
« Reply #15 on: July 08, 2010, 11:06:29 AM »
Doesn't that depend on his approach speed and angle of descent?

Offline syth82

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Re: So can you go downwind faster than windspeed?
« Reply #16 on: July 08, 2010, 05:46:40 PM »
If you're pissing into a 50mph headwind, how hard do you have to push to keep from getting your pants wet, and what injuries will you incur from pushing so hard? 

i think, with a 50mph wind, your best bet would be to lie down and hope it clears your hair....
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Offline BobbyR

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Re: So can you go downwind faster than windspeed?
« Reply #17 on: July 08, 2010, 06:52:02 PM »
if a man speaks deep in a forest, and there's no woman there to hear him, is he still wrong??   ;D
Of course he is. We are always wrong.  ;D 
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Offline Pinhead

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Re: So can you go downwind faster than windspeed?
« Reply #18 on: July 08, 2010, 08:22:05 PM »
Well....ahhh No .... unless the belt has some associated devices to create drag,  then the air passing below the plane would have it's own wind speed.... which would allow the aircraft to lift off the belt once the wind speed exceeded it's minimum take off speed.

Now the next question.... if your flying forward at 200mph and fire rockets.... will the 400mph rocket be going 600mph or 400mph?

Depends on if the aircraft is fully functional or not. Since the original question doesn't quantify "aircraft," it must be assumed that the vehicle is a fully-functional aircraft which means it has a working engine. This means it will produce thrust independent of wheel speed.

So yes, the plane can take off on a conveyor; the wheels will just be spinning faster than if the aircraft was lifting off static ground.
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Offline Retro Rocket

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Re: So can you go downwind faster than windspeed?
« Reply #19 on: July 08, 2010, 10:24:11 PM »
Well....ahhh No .... unless the belt has some associated devices to create drag,  then the air passing below the plane would have it's own wind speed.... which would allow the aircraft to lift off the belt once the wind speed exceeded it's minimum take off speed.

Now the next question.... if your flying forward at 200mph and fire rockets.... will the 400mph rocket be going 600mph or 400mph?

Depends on if the aircraft is fully functional or not. Since the original question doesn't quantify "aircraft," it must be assumed that the vehicle is a fully-functional aircraft which means it has a working engine. This means it will produce thrust independent of wheel speed.

So yes, the plane can take off on a conveyor; the wheels will just be spinning faster than if the aircraft was lifting off static ground.

Now you've done it....... ;D

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