This Should Leave Your Brain In A Knot- Part 2!

[TREKER]

Okay, my take here....

I am 100% in Flying Lows camp...

IMHO, if the plane (not wheels) needs to be traveling @ 150 mph for take off. Then the only way that plane takes off on a belt is if the engines are going full thottle and they are in a 150mph hurricane winds. The wind is what produces lift. Without the wind, no lift, no flight. Doesnt matter how fast the wheels are moving. Without wind, no matter how much thrust you are creating it is being countered by the treadmill.

Question now is..... If the plane was still on the treadmill and moving freely (wheels not locked). And if a pilot was at the controls. Add the take off speed winds in, would the plane be able to hover in place? Sounds feasible

I am a Trekker, in space we dont care about this crap... LOL

 

[Black1]

An aircraft carrier doing 50mph? That's friggin' hysterical. Top speed for those is, like, 6.
(I know Smoke was only using it as an example....and not living in some kinda fantasy world).


From Rachel:
"Of course the plane doesn't take off. It's pre-flight."

He's not as far off as you think.... Carriers actually move pretty quick for their size. A Nimitz Class can do 30 knots. :rock:

 

[FlyingLow]

As far as I can tell I think I was wrong. I'm still having trouble dealing with the fact that I could be wrong and I might have to fail my flight students today cause of it. What made me change my mind you ask? It was this thread: http://www.airwarriors.com/forum/showthread.php?t=137919&highlight=conveyor and the way it was worded. The engines acting on air comment from above was misinterpreted by me until I reread it on the other thread. I was thinking engines pushing on air and that air flowing over the wings is what was being said. Anyways I still have my doubts just because I want to see this happen. But I can admit that I was wrong. So on that note:

 

[ntw0rk]

Okay, my take here....

I am 100% in Flying Lows camp...

IMHO, if the plane (not wheels) needs to be traveling @ 150 mph for take off. Then the only way that plane takes off on a belt is if the engines are going full thottle and they are in a 150mph hurricane winds. The wind is what produces lift. Without the wind, no lift, no flight. Doesnt matter how fast the wheels are moving. Without wind, no matter how much thrust you are creating it is being countered by the treadmill.

Question now is..... If the plane was still on the treadmill and moving freely (wheels not locked). And if a pilot was at the controls. Add the take off speed winds in, would the plane be able to hover in place? Sounds feasible

Bahahahah!!!!! You just blew your whole theory out of the water with your last question!!! Read that again! the belt moving under it does not provide ANY wind power at all! And that is what is needed for the plane to achieve lift! No the plane will not hover! In order for the plane to fly it has to be moving through the AIR, the ground really doesn't have anything to do with it! Look at rockets, they don't need the ground at all, once they leave the launchpad. It doesn't matter to them that the earth is moving sideways under them. So then, why would it matter to the plane?

 

[ntw0rk]

He's not as far off as you think.... Carriers actually move pretty quick for their size. A Nimitz Class can do 30 knots. :rock:

Yeup, and that is PUBLISHED speed! I know on my radar, I have seen otherwise!!

[FONT=Arial,Helvetica]30[/FONT] [FONT=Arial,Helvetica]Knots[/FONT] [FONT=Arial,Helvetica]=[/FONT] [FONT=Arial,Helvetica]34.6[/FONT] [FONT=Arial,Helvetica]MPH[/FONT]

 

[TREKER]

As far as I can tell I think I was wrong. I'm still having trouble dealing with the fact that I could be wrong and I might have to fail my flight students today cause of it. What made me change my mind you ask? It was this thread: http://www.airwarriors.com/forum/showthread.php?t=137919&highlight=conveyor and the way it was worded. The engines acting on air comment from above was misinterpreted by me until I reread it on the other thread. I was thinking engines pushing on air and that air flowing over the wings is what was being said. Anyways I still have my doubts just because I want to see this happen. But I can admit that I was wrong. So on that note:

Now you f-ing say this... WTF??? LOLOLO(LLOLLOL

After I just followed you the entire way... Jeez... All I needed to do was wait a few more minutes.. LOLOLO

Actually I think you are wrong now...

 

[Black1]

...
I am a Trekker, in space we dont care about this crap... LOL

LMAO! :rock:

 

[Kevan]

He's not as far off as you think.... Carriers actually move pretty quick for their size. A Nimitz Class can do 30 knots. :rock:

Wow. Ya learn something new every day.
I thought they were big, slow, lumbering ships.
I was WAY off.

 

[TREKER]

Bahahahah!!!!! You just blew your whole theory out of the water with your last question!!! Read that again! the belt moving under it does not provide ANY wind power at all! And that is what is needed for the plane to achieve lift! No the plane will not hover! In order for the plane to fly it has to be moving through the AIR, the ground really doesn't have anything to do with it! Look at rockets, they don't need the ground at all, once they leave the launchpad. It doesn't matter to them that the earth is moving sideways under them. So then, why would it matter to the plane?

Got me wrong there Scotty.... Scotty... HAHAHAhAA Like in star trek.... The plane is moving through the air, just not from the thrust of the engines but from nature!!!! Sustained 150 mph winds... Same as the plane moving at 150mph on a runway on a day with no wind speed.

Anyway... My point is that no wind is generated from the plane moving to achieve lift because the treadmill would be be countering the planes ability to generate wind flow over the wings creating the lift.

My question had the planes wheels able to move WITH the wind moving over the wings generating lift. I would think that the wheels being locked would dinimish the strength the wind have based on friction.

My question again...
1. plane on treadmill
2. wheels moving freely
3. pilot at controls
4. engines full throttle
5. 150 mph winds (or whatever wind speed a plane would need for take off)

Would the plane lift off from the ground and hover. My guess is yes. And if you added power, it would actually be able to fly from there.

 

[ntw0rk]

Got me wrong there Scotty.... Scotty... HAHAHAhAA Like in star trek....

Anyway... My point is that no wind is generated from the plane moving to achieve lift because the treadmill would be be countering the planes ability to generate wind flow over the wings creating the lift.

My question had the planes wheels able to move WITH the wind moving over the wings generating lift. I would think that the wheels being locked would dinimish the strength the wind have based on friction.

My question again...
1. plane on treadmill
2. wheels moving freely
3. pilot at controls
4. engines full throttle
5. 150 mph winds (or whatever wind speed a plane would need for take off)

Would the plane lift off from the ground and hover. My guess is yes. And if you added power, it would actually be able to fly from there.

Ok, I see what you are saying, take off speed = wind speed in opposite directions. Yes, the plane would be flying in one spot, which is actually different than hovering! This is, again, why carriers face the wind and speed up, it helps the plane take off in a (much) shorter distance.

But, with this reference we can see that it is the wind speed over the wings, not the ground, the wheels or the "treadmill" that have anything to do with lift!

 

[Roz]

:dito: :withstupid: :rock: :canabis: :cheers:

 

[TREKER]

Ok, I see what you are saying, take off speed = wind speed in opposite directions. Yes, the plane would be flying in one spot, which is actually different than hovering! This is, again, why carriers face the wind and speed up, it helps the plane take off in a (much) shorter distance.

But, with this reference we can see that it is the wind speed over the wings, not the ground, the wheels or the "treadmill" that have anything to do with lift!

I am seeing the wind speed thing here...

Actually what I was picturing was a jet liner with the engines pushing it down the runway. A prop plane may be different because it is being pulled rather than pushed. I assume the prop plane would be creating wind / lift from pulling wind over the wings. The speed at the wheels at that point would not matter. The prop plane would techincally generate lift as long as wind being pulled over the wing. In a Jet plane, nothing is generating the wind over the wings to create lift.

Can we get clarfication on this maybe? would a prop plane act differntly than a jet? :dontknow:

 

[Black1]

I am seeing the wind speed thing here...

Actually what I was picturing was a jet liner with the engines pushing it down the runway. A prop plane may be different because it is being pulled rather than pushed. I assume the prop plane would be creating wind / lift from pulling wind over the wings. The speed at the wheels at that point would not matter. The prop plane would techincally generate lift as long as wind being pulled over the wing. In a Jet plane, nothing is generating the wind over the wings to create lift.

Can we get clarfication on this maybe? would a prop plane act differntly than a jet? :dontknow:

I'm with you on this one.... I would think a jet would act differently than a prop plane. :dontknow:

 

[Roz]

I wouldn't think it'd matter either way, whether it was jet powered or prop powered.

It still all boils down to the (freely spinning) wheels being totally unrelated to how an airplane's engine works.

The more I think about it, I think the wheels WOULD NOT roll at all in this equation. I think the jet would would apply thrust and since the "ground" below it would "move" (freely) the treadmill would move in the SAME direction as the plane and MAYBE assist in take off. - Much like an aircraft carrier going FIFTY MPH!

 

[Black1]

I wouldn't think it'd matter either way, whether it was jet powered or prop powered.

It still all boils down to the (freely spinning) wheels being totally unrelated to how an airplane's engine works.

The more I think about it, I think the wheels WOULD NOT roll at all in this equation. I think the jet would would apply thrust and since the "ground" below it would "move" (freely) the treadmill would move in the SAME direction as the plane and MAYBE assist in take off. - Much like an aircraft carrier going FIFTY MPH!

Ah, but you see, with a jet the air isn't moving over the WINGS (creating lift).... The thrust of the jet is pushing the plane, not the air. :dontknow:

 

[Roz]

Ah, but you see, with a jet the air isn't moving over the WINGS (creating lift).... The thrust of the jet is pushing the plane, not the air. :dontknow:

But if the jet is MOVING forward, air is definately flowing over the wings. Right?

 

[ntw0rk]

In a prop plane, the props are merely generating thrust, just in a different way than the jet. They are NOT providing "wind-over-the-wing" lift.

The propulsion for both is provided by increasing the amount of air pushing past the blades. Thereby increasing the air pressure behind the blade pushing the aircraft forward.

The lift is created when the aircraft moves through the air enough so that the wind flowing over the wings creates less pressure under the wing than over, Voila: lift!

 

[Kevan]

I spent the afternoon with two friends and posed this question to them.
Both are professional pilots: one pilots an Airbus A320 for United; the other just moved from a CRJ with USAir to a brand new Global 5000 and is a private pilot for The Limited (Victoria's Secret).
Both have over 12,000 hrs. of flight time, each (that's almost 1.5 continuous YEARS behind the controls. Each.).

One answered, "Yes. It will take off."
The other, "No. Ground speed is zero. It will not take off."

 

[Django]

Oh, get a fkn Harrier jump jet...............

D

 

[ntw0rk]

Maybe this will help us answer the question!!

If he was running on a treadmill....