Will the plane take off v.2?

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ScottMac

Moderator<br>Networking<br>Elite member
Mar 19, 2001
5,471
2
0
OP: DIAF for bringing this up again.

The mechanics and physics haven't changed, water or treadmill. Same / Same.

The plane take off.

 

KillerCharlie

Diamond Member
Aug 21, 2005
3,691
68
91
Originally posted by: ScottMac
OP: DIAF for bringing this up again.

The mechanics and physics haven't changed, water or treadmill. Same / Same.

The plane take off.

You're wrong.

In the water case, you're dragging the pontoons against the water. The faster the current, the more skin friction against the pontoons, requiring more force to take off.

In the treadmill case, the friction force on the airplane from the wheels is NOT dependent on the speed of the wheels.

In this case, though, the question is "how fast is the current" because whether or not it will take off depends on this. In the treadmill case, the speed is not relevant.

<--- Professional aerodynamicist for major airplane manufacturer
 

Number1

Diamond Member
Feb 24, 2006
7,881
549
126
Originally posted by: KillerCharlie
Originally posted by: ScottMac
OP: DIAF for bringing this up again.

The mechanics and physics haven't changed, water or treadmill. Same / Same.

The plane take off.

You're wrong.

In the water case, you're dragging the pontoons against the water. The faster the current, the more skin friction against the pontoons, requiring more force to take off.

In the treadmill case, the friction force on the airplane from the wheels is NOT dependent on the speed of the wheels.

In this case, though, the question is "how fast is the current" because whether or not it will take off depends on this. In the treadmill case, the speed is not relevant.

<--- Professional aerodynamicist for major airplane manufacturer

Time to find another job!!!!!

Muthbuster is going to do the plane on a threadmill story in December I believe.
 

KillerCharlie

Diamond Member
Aug 21, 2005
3,691
68
91
Originally posted by: Number1
Originally posted by: KillerCharlie
Originally posted by: ScottMac
OP: DIAF for bringing this up again.

The mechanics and physics haven't changed, water or treadmill. Same / Same.

The plane take off.

You're wrong.

In the water case, you're dragging the pontoons against the water. The faster the current, the more skin friction against the pontoons, requiring more force to take off.

In the treadmill case, the friction force on the airplane from the wheels is NOT dependent on the speed of the wheels.

In this case, though, the question is "how fast is the current" because whether or not it will take off depends on this. In the treadmill case, the speed is not relevant.

<--- Professional aerodynamicist for major airplane manufacturer

Time to find another job!!!!!

Muthbuster is going to do the plane on a threadmill story in December I believe.

Sorry, Mythbusters are stupid.
 

Number1

Diamond Member
Feb 24, 2006
7,881
549
126
Originally posted by: KillerCharlie
Originally posted by: Number1
Originally posted by: KillerCharlie
Originally posted by: ScottMac
OP: DIAF for bringing this up again.

The mechanics and physics haven't changed, water or treadmill. Same / Same.

The plane take off.

You're wrong.

In the water case, you're dragging the pontoons against the water. The faster the current, the more skin friction against the pontoons, requiring more force to take off.

In the treadmill case, the friction force on the airplane from the wheels is NOT dependent on the speed of the wheels.

In this case, though, the question is "how fast is the current" because whether or not it will take off depends on this. In the treadmill case, the speed is not relevant.

<--- Professional aerodynamicist for major airplane manufacturer

Time to find another job!!!!!

Muthbuster is going to do the plane on a threadmill story in December I believe.

Sorry, Mythbusters are stupid.

I find the show quite entertaining.
 

Chaotic42

Lifer
Jun 15, 2001
34,966
2,121
126
Originally posted by: Number1
Time to find another job!!!!!

Muthbuster is going to do the plane on a threadmill story in December I believe.
No, he's right. The pontoons are directly connected to the airplane, and any force that affects them will affect the entire aircraft.

<--- Cartographer
 

Number1

Diamond Member
Feb 24, 2006
7,881
549
126
Originally posted by: Chaotic42
Originally posted by: Number1
Time to find another job!!!!!

Muthbuster is going to do the plane on a threadmill story in December I believe.
No, he's right. The pontoons are directly connected to the airplane, and any force that affects them will affect the entire aircraft.

<--- Cartographer

On second tought, he might be right. A current strong enough might generate enough friction to stop the plane.

<---Radio Technician
 

irishScott

Lifer
Oct 10, 2006
21,562
3
0
Originally posted by: ultimatebob
Originally posted by: SoulAssassin
If Mythbusters do this I hope they blow the plane up at the end for no scientific reason.

They also need an excuse to have Kari Byron in a skimpy swimsuit. Maybe they should sink it and make her recover the blackbox or something.

Already done.

http://www.loveredheads.com/wp...6/08/kari_byron_02.jpg (SFW)
http://saturn5.com/darwin/beef...adio_belly_800x600.jpg (SFW)
http://saturn5.com/darwin/beef...adio_smile_800x600.jpg (SFW)
 

altonb1

Diamond Member
Feb 5, 2002
6,432
0
71
Originally posted by: Ctrackstar126
I feel bad for the random people who come and read the forums. For people who dont know the history these threads would just be a big WTF. Actually I know the history and its still a WTF

QFT
 

montypythizzle

Diamond Member
Nov 12, 2006
3,698
0
71
Originally posted by: irishScott
Originally posted by: ultimatebob
Originally posted by: SoulAssassin
If Mythbusters do this I hope they blow the plane up at the end for no scientific reason.

They also need an excuse to have Kari Byron in a skimpy swimsuit. Maybe they should sink it and make her recover the blackbox or something.

Already done.

http://www.loveredheads.com/wp...6/08/kari_byron_02.jpg (SFW)
http://saturn5.com/darwin/beef...adio_belly_800x600.jpg (SFW)
http://saturn5.com/darwin/beef...adio_smile_800x600.jpg (SFW)

n00dz?

2nd and 3rd linkz need teh fix.

*FAP* *FAP* *FAP*
 

Jeff7

Lifer
Jan 4, 2001
41,596
20
81
Originally posted by: KillerCharlie
Originally posted by: ScottMac
OP: DIAF for bringing this up again.

The mechanics and physics haven't changed, water or treadmill. Same / Same.

The plane take off.

You're wrong.

In the water case, you're dragging the pontoons against the water. The faster the current, the more skin friction against the pontoons, requiring more force to take off.

In the treadmill case, the friction force on the airplane from the wheels is NOT dependent on the speed of the wheels.

In this case, though, the question is "how fast is the current" because whether or not it will take off depends on this. In the treadmill case, the speed is not relevant.

<--- Professional aerodynamicist for major airplane manufacturer
Coefficient of friction was never defined in the original problem, nor was the geometry of the pontoons. For all we know the water could be in a super-fluid state.

 

TecHNooB

Diamond Member
Sep 10, 2005
7,458
1
76
The plane never takes off. In either case. Who seriously thinks the plane will take off?
 

preslove

Lifer
Sep 10, 2003
16,754
64
91
Why wouldn't the plane just turn around and go with the current? I assume that this would be SOP.
 

smack Down

Diamond Member
Sep 10, 2005
4,507
0
0
Originally posted by: Chaotic42
Originally posted by: Number1
Time to find another job!!!!!

Muthbuster is going to do the plane on a threadmill story in December I believe.
No, he's right. The pontoons are directly connected to the airplane, and any force that affects them will affect the entire aircraft.

<--- Cartographer

Don't know what kind of a plane you fly on but everyone i have the wheels are directly connected to the plane.
 

Bill Brasky

Diamond Member
May 18, 2006
4,324
1
0
Another issue is that as the plane gains speed, some lift will be created slightly raising the pontoons in the water. This will reduce pontoon/water contact and reduce friction, allowing the plane to gain more speed. Most likely the plane will take off, but there are too many undefined variables to know.
 

Tylanner

Diamond Member
Sep 18, 2004
5,481
2
81
Depends if it can attain necessary relative speed to take off, EXACT same question (and just as stupid/useless) and answer as the treadmill, regardless of how you want interpret the friction.

A treadmill and a current would both force a "thrust less" plane backward.

The question is not definitively answerable, but it can be interpreted and clarified.