shrockworks xterraparts
XOC Decal
Newest Members
Glim, ChossWrangler, Patman, ChargedX, Randy Howerton
10084 Registered Users
Recent Posts
Shout Box

Who's Online
0 registered (), 63 Guests and 3 Spiders online.
Key: Admin, Global Mod, Mod
Page 26 of 43 < 1 2 ... 24 25 26 27 28 ... 42 43 >
Topic Options
Rate This Topic
#617700 - 01/01/07 12:23 PM Re: Know that if you do not post in this thread today the human race may cease to exist
XPLORx4 Offline
Member

Registered: 23/03/01
Posts: 1906
Loc: San Jose, CA
You all know that the real answer is that EVERYONE'S right! The plane can either NOT fly or it CAN fly! [LOL] Hahahaha!
_________________________
4x4 in uppercase is $X$!!!
1997 R50: VG33E/RE4R01A/TX10/3.7/R200A/ARB/4.636/H233B/ARB/4.636/321150R15

Top
#617701 - 01/01/07 12:37 PM Re: Know that if you do not post in this thread today the human race may cease to exist
Rockaholic Offline
Member

Registered: 18/02/02
Posts: 1632
Loc: Reading, MA
Quote:
Originally posted by BlueSky:
Go back in your corner. He can handle his own conversation.
OK - I asked you a question, and you've chosen to ignore it... I wasn;'t jumping into "your" conversation, as much as I've been waiting for an answer from you to mine.
So let me show you the problem with your argument...and pay atention this time. I understand you claim to be a "a fairly intelligent person with a long background in aviation." So why don't you prove that and read thorugh this and show me where I'm wrong.

Quote:
Originally posted by BlueSky:
It's a given that the tires are mounted on freewheeling, unpowered wheels. Still, something has to happen for any wheeled craft or vehicle to move.

For our purposes, let's define "roll" as rotation over stationary ground, resulting in movement. "Movement" means covering a given distance. Agree? Good.
Ok, so based on that statrement a plane moving at 100mph with it's wheels on solid ground must have the wheels rolling over the ground at 100mph.

Quote:
For an aircraft at rest on the ground with the landing gear down, how does [b]any kind of propelling force - a tow tractor, people pushing, engine power, or a downhill slope as examples - become forward motion? How does the plane itself accelerate forward? Move from point A to point B? How does ANY FORCE applied to the plane result in forward movement?

One thing must happen for the plane to move. The tires must roll. It doesn't matter how that propelling force is applied but for that aircraft to move forward, the tires, mounted on their freewheeling, unpowered wheels, must roll. That's why we need brakes and wheel chocks, right?
[/b]
OK, I'm going to give you that one....

Quote:

What happens when the tires, mounted on their freewheeling, unpowered wheels, roll? The plane moves along the ground. This is, IMHO, one missing link for the WFers - the rolling tires only travel forward because [b]the ground is stationary
. That distance, as we know, is a certain amount per tire rotation depending on their size.

But when the belt is added, the ground under the plane is in effect moving in the opposite direction. Forward movement is no longer the result of applying any kind of propelling force because...why?

The tires are no longer rolling along the stationary ground, they're rotating in place. And since the freewheeling, unpowered wheels they're mounted upon are on an axle attached to the plane, if the tires are not moving forward, neither is the plane.[/b]
Ok, now you have a problem with your argument- it's flawed - badly.
Here's why:

If the plane has the front wheels on the conveyor belt and the rear wheels on solid ground - you now have a contradiction.

According to you the plane will not move because the front wheels are on the conveyor and "the ground under the plane is in effect moving in the opposite direction. Forward movement is no longer the result of applying any kind of propelling force because the tires are no longer rolling along the stationary ground, they're rotating in place. And since the freewheeling, unpowered wheels they're mounted upon are on an axle attached to the plane, if the tires are not moving forward, neither is the plane."

But the rear wheels are on solid ground and since the plane is moving at 100mph, "One thing must happen for the plane to move. The tires must roll. It doesn't matter how that propelling force is applied but for that aircraft to move forward, the tires, mounted on their freewheeling, unpowered wheels, must roll."

Now the problem is that the front and rear wheels are mounted to the exact same plane. Now based on what you claim, the planes wheels on the conveyor do not move in relation to the ground (no rolling) because that counteracts the planes speed of 100mph, yet the rear wheels must roll because the plane is moving at 100mph (otherwise the conveyor isn't moving at all), and since they roll that means they move in relation to the ground...

So now I ask you again:
[b]How do the front wheels remain stationary while the rear wheels are moving when the distance between the wheels remains a constant?[/b}
_________________________
Jeffrey
I'm just trying to put my tires on the rocks of life.

Top
#617702 - 01/01/07 12:48 PM Re: Know that if you do not post in this thread today the human race may cease to exist
XPLORx4 Offline
Member

Registered: 23/03/01
Posts: 1906
Loc: San Jose, CA
-----------------
SCENARIO: A plane is standing on a runway that can move (like a giant conveyor belt). This conveyor has a control system that tracks the plane's speed and tunes the speed of the conveyor to be exactly the same (but in the opposite direction).

Will the plane be able to take off?

-----------------

Here's my position:

The plane CAN FLY if.... see below.
The plane CAN NOT FLY if.... see below.

Here are the facts, which both CF and CNF folks agree on (I hope!)

FACT #1: Airspeed is an essential element to flight of a fixed-wing aircraft.
FACT #2: Groundspeed is irrrelevant to flight. It's only relevant if you actually hope for a plane to do anything except hover in mid-air.
FACT #3: AIrcraft use a Pitot tube , usually mounted on the wing, to measure airspeed.
FACT #3: Aircraft use GPS and radio-based distance measuring equipment to measure groundspeed.
FACT #4: In the absence of wind, airspeed and groundspeed are equal.
FACT #5: On an aircraft, wheel RPM, or wheelspeed, is irrelevant to both groundspeed and airspeed.
FACT #6: Airplane engines apply thrust against air.
FACT #7: Drag resists motion through air.
FACT #8: Friction resists motion on the ground.

-----------------

ASSUMPTION #1: The pilot knows how to operate the aircraft and can successfully take off on a normal runway.
ASSUMPTION #2: Windspeed = 0mph
ASSUMPTION #3: The plane has wheels.
ASSUMPTION #4: The wheels are the only part of the plane in contact with the conveyor belt.
ASSUMPTION #5: The moving conveyor belt does not create wind that has a significant impact on the plane.
ASSUMPTION #6: The tires and wheel bearings on the airplane are NOT frictionless.
ASSUMPTION #7: There is a physical limit to the maximum RPM that the plane tires and wheel bearings can rotate before failure.
ASSUMPTION #8: Based on the question, "Will the plane be able to take off?" we only care about FLIGHT. By association to FACT #1, we therefore only care about AIRSPEED.

-----------------

CONCLUSION #1: Based on ASSUMPTION #8, "plane's speed" means AIRSPEED.
CONCLUSION #2: Based on ASSUMPTION #2 and FACT #4, groundspeed = airspeed.
CONCLUSION #3: Based on CONCLUSION #2, "speed of the conveyor" means "negative GROUNDSPEED".
CONCLUSION #4: Based on CONCLUSION #2, the plane MUST ALWAYS HAVE a measurable groundspeed and airspeed or the conveyor would stop moving.
CONCLUSION #5: Based on CONCLUSION #4 and ASSUMPTION #5, the conveyor MUST ALWAYS HAVE a measurable negative groundspeed, but NEVER HAS a measurable negative airspeed.
CONCLUSION #6: Based on CONCLUSION #3, ASSUMPTIONS #4 and #5, and FACT #5, the conveyor does not negate airspeed.
CONCLUSION #7: Based on CONCLUSION #4 and CONCLUSION #6, the plane moves forward.

THEREFORE... the ANSWER to the question is:
Yes, the plane takes off if the thrust from the engine can overcome the wheel bearing friction and propel the aircraft to liftoff airspeed before the runway ends or before the tires and wheel bearings fail.
No, the plane does not take off if the engine thrust is insufficient to overcome wheel bearing friction before the runway ends or before the tires or wheel bearings fail.
_________________________
4x4 in uppercase is $X$!!!
1997 R50: VG33E/RE4R01A/TX10/3.7/R200A/ARB/4.636/H233B/ARB/4.636/321150R15

Top
#617703 - 01/01/07 12:51 PM Re: Know that if you do not post in this thread today the human race may cease to exist
TJ Offline
Member
*****

Registered: 08/03/01
Posts: 7756
Loc: Lawrenceville, NJ, USA
CONCLUSION #3: Based on CONCLUSION #2, "speed of the conveyor" means "negative GROUNDSPEED".
CONCLUSION #4: Based on CONCLUSION #2, the plane MUST ALWAYS HAVE a measurable groundspeed and airspeed.
CONCLUSION #5: Based on CONCLUSION #4 and ASSUMPTION #5, the conveyor MUST ALWAYS HAVE a measurable negative groundspeed, but NEVER HAS a measurable negative airspeed.

Hmm...damn...I THOUGHT we all got it.

The conveyor DOES NOT change your ground speed.

If ground speed is the same as air speed in zero mph wind...and I fly over a river flowing towards me...I am covering the same ground...but the "ground" is flowing water.

A flowing conveyor belt is as much a part of my ground speed as a flowing river...or a highrway with cars under me...even if my tires are rolling on the car's roofs...the car roofs do not change my ground speed either.

laugh

Actually, we might be done.

I don't think there's any one left who doesn't get it.

laugh

The last key seemed to be "SPEED".

The CF camp confused OR misinterpreted SPEED as the speed of the conveyor being MATCHED to the speed of the PLANE - as meaning more than it did.

That's why all the seemingly odd references to the plane going at some speed, and the conveyor matching it...so it was standing still, etc.

As soon as each one realized that the conveyor's speed - while NUMERICALLY the same as the PLANE's speed (like a tread mill), was not in fact ACTUALLY the plane's speed.

As soon as they realized that your SPEED on a tread mill is zero, but your ROTATIONAL SPEED was what ever the belt speed was going around at...it became clear.

UNTIL the concept that your SPEED is zero when staying in place on a tread mill, even if the speedometer SAYS 4 mph...is absorbed, no further progress could be made.

I think we're all onboard now though.

laugh
_________________________
- TJ

2001 Xterra '03 VG33, SE 5 spd, 305/70/16's, Revolvers, UBSkidderz, Doubled AAL's, 3"SL/2"BL, winch/bumpers, skids, sliders, OBA, Snorkel, pine stripes....

Friends don't let friends drive stock.

http://www.gifsoup.com/view/501230/tj-tackling-crawlers-ridge-o.gif

Top
#617704 - 01/01/07 01:05 PM Re: Know that if you do not post in this thread today the human race may cease to exist
XPLORx4 Offline
Member

Registered: 23/03/01
Posts: 1906
Loc: San Jose, CA
Quote:
Originally posted by TJ:
Hmm...damn...I THOUGHT we all got it.

I think we're all onboard now though.

laugh
TJ, you missed FACT#1, ASSUMPTION#8, and CONCLUSION#6.

You're right, we don't care about "negative groundspeed" at all. All we care about is airspeed.

However, if the plane's wheel bearings impart sufficient friction to the aircraft, then it won't ever develop enough airspeed to take off. But, IMO, that would be a very poorly designed aircraft.
_________________________
4x4 in uppercase is $X$!!!
1997 R50: VG33E/RE4R01A/TX10/3.7/R200A/ARB/4.636/H233B/ARB/4.636/321150R15

Top
#617705 - 01/01/07 01:15 PM Re: Know that if you do not post in this thread today the human race may cease to exist
Rockaholic Offline
Member

Registered: 18/02/02
Posts: 1632
Loc: Reading, MA
Quote:
Originally posted by XPLORx4:
Quote:
Originally posted by TJ:
[b]Hmm...damn...I THOUGHT we all got it.

I think we're all onboard now though.

laugh
TJ, you missed FACT#1, ASSUMPTION#8, and CONCLUSION#6.

You're right, we don't care about "negative groundspeed" at all. All we care about is airspeed.[/b]
Yes, except for one problem - there is no fact or assumption that the plane remains in one spot relative to the ground. That would be a false assumption

Let me take my "front wheels on coneyor, rear wheel on ground" one step farther.

The planes starts with no speed with the front wheels on the conveyor and the rear rears off the conveyor.

The conveyor is set to match the speed of the plane, so whatever the plane's speed is at any exact moment the conveyors speed is.

As the planes speed increases, does the plane move (not neccessairly take flight) with repect to the ground?

If the plane moves, then the plane on a conveyor flies.

If the plane does not move, then the plane on the conveyor does not fly

Since it would be impossible for the rear wheel to be on solid ground and not moving when the plane has a speed of anything greater than 0mph, then of course the plane moves, and thus the plane on the conveyor must fly.
_________________________
Jeffrey
I'm just trying to put my tires on the rocks of life.

Top
#617706 - 01/01/07 01:20 PM Re: Know that if you do not post in this thread today the human race may cease to exist
BlueSky Offline
Member

Registered: 17/08/00
Posts: 2286
Loc: Georgia

Top
#617707 - 01/01/07 01:20 PM Re: Know that if you do not post in this thread today the human race may cease to exist
XPLORx4 Offline
Member

Registered: 23/03/01
Posts: 1906
Loc: San Jose, CA
Quote:
Originally posted by Rockaholic:
Yes, except for one problem - there is no fact or assumption that the plane remains in one spot relative to the ground.
You missed conclusion #4.
_________________________
4x4 in uppercase is $X$!!!
1997 R50: VG33E/RE4R01A/TX10/3.7/R200A/ARB/4.636/H233B/ARB/4.636/321150R15

Top
#617708 - 01/01/07 01:24 PM Re: Know that if you do not post in this thread today the human race may cease to exist
XPLORx4 Offline
Member

Registered: 23/03/01
Posts: 1906
Loc: San Jose, CA
Quote:
Originally posted by BlueSky:
IF you WFers are correct, is the distance needed for takeoff more, less, or the same as needed on a runway?

How did you reach your answer?
Distance needed for takeoff is greater on a conveyor belt than on a conventional runway.

Why? Because the friction of wheel bearings spinning at twice their normal speed creates an opposing force to the engine thrust. As my previous posts have indicated, if the wheel bearing friction is so great that the engines can't overpower that force, then that's either a poorly designed or poorly maintained aircraft.
_________________________
4x4 in uppercase is $X$!!!
1997 R50: VG33E/RE4R01A/TX10/3.7/R200A/ARB/4.636/H233B/ARB/4.636/321150R15

Top
#617709 - 01/01/07 01:33 PM Re: Know that if you do not post in this thread today the human race may cease to exist
Rockaholic Offline
Member

Registered: 18/02/02
Posts: 1632
Loc: Reading, MA
Quote:
Originally posted by BlueSky:
To answer your question:

My hypothesis is based on the scenario given, that all aircraft tires are on the belt.

In yours, it seems to me the front tires would rotate faster than the rear ones but the aircraft would continue moving forward until all tires were on the belt, at which time the aircraft's forward motion would cease and all tires would rotate in place.

Does that answer your question?
No, you create a new problem -

You have the plane moving at 100 mph, and the front wheels moving at 100 mph going forward on a conveyor belt moving -100mph and then just stopping.

What force is being applied that stops the forward motion of the plane?
You can't say the motion of the conveyor belt, because if that were true the front wheels of the plane would not be able to move forward in relation to the ground on the belt.

Quote:
Originally posted by BlueSky:
IF you WFers are correct, is the distance needed for takeoff more, less, or the same as needed on a runway?

How did you reach your answer?
The distance the plane travels on the ground for takeoff is the same for either the gorund or the conveyor. The distance the wheels "travel" (that is based on rational speed) on the conveyor belt is twice the distance the wheels travel on the ground becuase their rotaional speed is double.

2 tires of the same size, one turning at 1rpm and theother turning at 2rpm travel different lenghts of ground in the same time. The tire turning 2rpm travels twice the distance of the tire turing 1rpm in the same time amount.
_________________________
Jeffrey
I'm just trying to put my tires on the rocks of life.

Top
#617710 - 01/01/07 01:36 PM Re: Know that if you do not post in this thread today the human race may cease to exist
XPLORx4 Offline
Member

Registered: 23/03/01
Posts: 1906
Loc: San Jose, CA
Quote:
Originally posted by Rockaholic:
Quote:
Originally posted by BlueSky:
[b]To answer your question:

My hypothesis is based on the scenario given, that all aircraft tires are on the belt.

In yours, it seems to me the front tires would rotate faster than the rear ones but the aircraft would continue moving forward until all tires were on the belt, at which time the aircraft's forward motion would cease and all tires would rotate in place.

Does that answer your question?
No, you create a new problem -

You have the plane moving at 100 mph, and the front wheels moving at 100 mph going forward on a conveyor belt moving -100mph and then just stopping.

What force is being applied that stops the forward motion of the plane?
You can't say the motion of the conveyor belt, because if that were true the front wheels of the plane would not be able to move forward in relation to the ground on the belt.[/b]
BlueSky answered the question as if the plane were a RWD car.
_________________________
4x4 in uppercase is $X$!!!
1997 R50: VG33E/RE4R01A/TX10/3.7/R200A/ARB/4.636/H233B/ARB/4.636/321150R15

Top
#617711 - 01/01/07 01:41 PM Re: Know that if you do not post in this thread today the human race may cease to exist
Rockaholic Offline
Member

Registered: 18/02/02
Posts: 1632
Loc: Reading, MA
Quote:
Originally posted by XPLORx4:
BlueSky answered the question as if the plane were a RWD car.
Again - that is a problem
A plane is not a RWD car, becasue a rear wheel drive cars wheels are not all free spinning (only the front tires are free spiining, the rear wheels are not, hence rear wheel drive), whereas an airplanes wheels are all free spinning.

If the free spinng wheels of the airplane are going to be stopped by the conveyor, then the RWD car should implode on itself, and not climb up onto the conveyor with the front wheels moving forward on the conveyor.

So now you've said that free spinning wheels can be stopped moving forward by the conveyor belt, and contradicted yourself by saying they can not be stopped moving forward by the conveyor belt - which is it?
_________________________
Jeffrey
I'm just trying to put my tires on the rocks of life.

Top
#617712 - 01/01/07 01:47 PM Re: Know that if you do not post in this thread today the human race may cease to exist
Rockaholic Offline
Member

Registered: 18/02/02
Posts: 1632
Loc: Reading, MA
Quote:
Originally posted by XPLORx4:
Quote:
Originally posted by Rockaholic:
[b]Yes, except for one problem - there is no fact or assumption that the plane remains in one spot relative to the ground.
You missed conclusion #4.[/b]
That conclusion does not say the plane remains in one spot - only that the conveyor matches the measerued airspeed and groundspeed of the plane

Thus if the plane is on the conveyor and not moving in relation to the ground (Groundspeed thus =0 mph) then the conveyor is moving at 0 mph...

Based on that conclusion if the conveyor has a speed, the plane must be moving in relation to the ground.

Since the plane is moving in relation to the ground, it will fly based on Conclusion #2 (airspeed = groundspeed)

The assumption that the plane remains stationary to one spot on the ground is faulty and incorrect
_________________________
Jeffrey
I'm just trying to put my tires on the rocks of life.

Top
#617713 - 01/01/07 01:57 PM Re: Know that if you do not post in this thread today the human race may cease to exist
XPLORx4 Offline
Member

Registered: 23/03/01
Posts: 1906
Loc: San Jose, CA
Quote:
Originally posted by Rockaholic:
The assumption that the plane remains stationary to one spot on the ground is faulty and incorrect
Which assumption or conclusion makes that claim? Certainly not me.

Quote:
CONCLUSION #4: Based on CONCLUSION #2, the plane MUST ALWAYS HAVE a measurable groundspeed and airspeed.
CONCLUSION #6: Based on CONCLUSION #3, ASSUMPTIONS #4 and #5, and FACT #5, the conveyor does not negate airspeed.
I never said the plane remains stationary, it just may not take off if it can't develop sufficient airspeed by the end of the runway.
_________________________
4x4 in uppercase is $X$!!!
1997 R50: VG33E/RE4R01A/TX10/3.7/R200A/ARB/4.636/H233B/ARB/4.636/321150R15

Top
#617714 - 01/01/07 02:03 PM Re: Know that if you do not post in this thread today the human race may cease to exist
Rockaholic Offline
Member

Registered: 18/02/02
Posts: 1632
Loc: Reading, MA
Quote:
Originally posted by XPLORx4:
Quote:
Originally posted by Rockaholic:
[b]The assumption that the plane remains stationary to one spot on the ground is faulty and incorrect
Which assumption or conclusion makes that claim? Certainly not me.
[/b]
See Bluesky's posts...
Bluesky's assuming the plane remains stationary.

Itr's an assumption not included in the list, but one that people are making.

The only way the plane does not take off is if the plane remains stationary - which is the heart of the question about will a plane on a conveyor take off.
_________________________
Jeffrey
I'm just trying to put my tires on the rocks of life.

Top
#617715 - 01/01/07 02:08 PM Re: Know that if you do not post in this thread today the human race may cease to exist
XPLORx4 Offline
Member

Registered: 23/03/01
Posts: 1906
Loc: San Jose, CA
Quote:
Originally posted by Rockaholic:
It's an assumption not included in the list, but one that people are making.
Yes, they are making an incorrect FALSE assumption. The scenario specifically states that the conveyor matches the plane's speed, and by inference, its airspeed, since that's how planes measure whether they can fly or not. If there's no wind, the plane must ALWAYS continue to move in order for the conveyor to have any kind of speed to react negatively to.

Quote:
The only way the plane does not take off is if the plane remains stationary - which is the heart of the question about will a plane on a conveyor take off.
That's actually not true. The plane could move all the way down the runway and still not take off if the wheel bearing friction was high enough to prevent the plane from acquiring enough airspeed.
_________________________
4x4 in uppercase is $X$!!!
1997 R50: VG33E/RE4R01A/TX10/3.7/R200A/ARB/4.636/H233B/ARB/4.636/321150R15

Top
#617716 - 01/01/07 02:11 PM Re: Know that if you do not post in this thread today the human race may cease to exist
Rockaholic Offline
Member

Registered: 18/02/02
Posts: 1632
Loc: Reading, MA
BTW - Bluesky does contracdict "him"self...

Quote:
Originally posted by BlueSky:
That pesky friction? It's WFer missing link #2. [b]You don't need enough to stop the plane, you only need enough to make the tires rotate. That's why the "perfect frictionless ice" scenario works, because the need for the tires to roll is effectively removed because there's not enough friction to make them rotate.

The plane would fly IF the belt was a constant speed less than the plane can attain or IF the belt did not speed up as power was applied to the aircraft's engines. In the scenario as presented, the aircraft's tires, mounted on their freewheeling, unpowered wheels, will merely rotate faster in place as thrust is applied but the plane will not move forward.[/b]
Quote:
Orignally posted by Blue Sky:
In yours, it seems to me the front tires would rotate faster than the rear ones but the aircraft would continue moving forward until all tires were on the belt, at which time the aircraft's forward motion would cease and all tires would rotate in place.
There's enough friction from the conveyor to roate the tires, but not enough to stop the plane from moving forward(quote#1)
Yet Bluesky seems to believe the friction of the conveyor will stop the forward motion of the plane on the conveyor (quote #2)
Which is it?
_________________________
Jeffrey
I'm just trying to put my tires on the rocks of life.

Top
#617717 - 01/01/07 02:11 PM Re: Know that if you do not post in this thread today the human race may cease to exist
Anonymous
Unregistered


Ok, if what's below you moving is all you have to overcome, how does the stewardess walk up and down the aisle if the plane is moving 500 mph?

Top
#617718 - 01/01/07 02:13 PM Re: Know that if you do not post in this thread today the human race may cease to exist
Rockaholic Offline
Member

Registered: 18/02/02
Posts: 1632
Loc: Reading, MA
Quote:
Originally posted by XPLORx4:
That's actually not true. The plane could move all the way down the runway and still not take off if the wheel bearing friction was high enough to prevent the plane from acquiring enough airspeed.
Since the coeffecient of friction between 2 objects is constant, if the wheel bearing friciton is high enough to prevent the plane from taking off on the conveyor, it's high enough to prevent the plane from taking off on a runway - which violates the assumption that the plane would take off on a normal runway
_________________________
Jeffrey
I'm just trying to put my tires on the rocks of life.

Top
#617719 - 01/01/07 02:14 PM Re: Know that if you do not post in this thread today the human race may cease to exist
XPLORx4 Offline
Member

Registered: 23/03/01
Posts: 1906
Loc: San Jose, CA
Quote:
Originally posted by Rockaholic:
BTW - Bluesky does contracdict "him"self...
Which is it?
Hahaha, maybe last night's festivities have had some consequences on his thinking ability this morning. [LOL]
_________________________
4x4 in uppercase is $X$!!!
1997 R50: VG33E/RE4R01A/TX10/3.7/R200A/ARB/4.636/H233B/ARB/4.636/321150R15

Top
#617720 - 01/01/07 02:20 PM Re: Know that if you do not post in this thread today the human race may cease to exist
XPLORx4 Offline
Member

Registered: 23/03/01
Posts: 1906
Loc: San Jose, CA
Quote:
Originally posted by Rockaholic:
Since the coeffecient of friction between 2 objects is constant, if the wheel bearing friciton is high enough to prevent the plane from taking off on the conveyor, it's high enough to prevent the plane from taking off on a runway - which violates the assumption that the plane would take off on a normal runway
But the coefficient of friction on the wheel bearings isn't constant. As the bearing grease heats up, its lubricating ability changes. And the ability of the tires to stay in one piece depends on how fast they can rotate. Let's say that a particular model of aircraft achieves liftoff speed at 120mph. For cost purposes, they install tires with a speed rating of 180mph, well above the speed the airplane might ever need when taking off or landing.

However, on the conveyor belt, the tire speed would be 240mph, exceeding the speed rating of the tire, and.... KABOOM! Blowout!
_________________________
4x4 in uppercase is $X$!!!
1997 R50: VG33E/RE4R01A/TX10/3.7/R200A/ARB/4.636/H233B/ARB/4.636/321150R15

Top
#617721 - 01/01/07 02:26 PM Re: Know that if you do not post in this thread today the human race may cease to exist
Rockaholic Offline
Member

Registered: 18/02/02
Posts: 1632
Loc: Reading, MA
If the bearings and tires were to fail, then "yes" the plane probably wouldn't fly...again assuming the plane has wheels

However, you are the only one here that seems to be making that particular argument.

If you assume upgraded bearings/tires to deal with those new stresses (like a stock Xterra being given a Body lift and larger, more aggressive tires to handle tougher offroad trails) for the scenario - then the plane flies.
_________________________
Jeffrey
I'm just trying to put my tires on the rocks of life.

Top
#617722 - 01/01/07 02:28 PM Re: Know that if you do not post in this thread today the human race may cease to exist
Anonymous
Unregistered


You people are unreal and digging too deep. Friction is negligible and therefore not an issue in this particular problem. If there were an issue with friction and the possibility of exploding the bearings/wheels/tires of the plane, then the same can be said for the wheel system on the conveyor belt. Therefore, the friction is a negligible and moot part of this experiment.

Top
#617723 - 01/01/07 02:29 PM Re: Know that if you do not post in this thread today the human race may cease to exist
Anonymous
Unregistered


Just want to add that with this post, we tie Phat Chick Fridays in post count [Wave]

Top
#617724 - 01/01/07 02:35 PM Re: Know that if you do not post in this thread today the human race may cease to exist
XPLORx4 Offline
Member

Registered: 23/03/01
Posts: 1906
Loc: San Jose, CA
Yes, in the real world, friction is a neglible force to counteract engine thrust. So, practically speaking, the average well-maintained would take off, whether on a conveyor belt or not.

It would, however, be interesting to find out what the speed rating of aircraft tires is, and whether they have >200% safety margin over takeoff speed.
_________________________
4x4 in uppercase is $X$!!!
1997 R50: VG33E/RE4R01A/TX10/3.7/R200A/ARB/4.636/H233B/ARB/4.636/321150R15

Top
Page 26 of 43 < 1 2 ... 24 25 26 27 28 ... 42 43 >



shrockworks xterraparts
XOC Decal