Pilots question

[jtexas]

Re: Pilots question

then if the plane isn't moving, the conveyor won't be moving either. sounds like a design flaw.

8)

 

[QC]

Re: Pilots question

How will the conveyor ever overcome the thrust of the propeller? Are you saying that the friction of the bearings and tires on the surface are enough to absolutely cancel all of the thrust generated by the engine? Imagine the 747 set up to fly with the Shuttle on its back. Now imagine it with no Shuttle. Are you contending that a conveyor moving the wheels one way laterally could exceed the load created on those same wheels and bearings by the Shuttle? If not, it could take off . . . I submit the friction of that conveyor could never reach the load of that shuttle sitting on it's back. And considering that the take off speed is around 100 MPH, how fast does the conveyor get to go in the opposite direction before it gives up? 100MPH? 200 MPH? 1 gazillion miles per hour?

I guess Bondo does originally have it right, 'cept I am not sure why we need to replace the conveyor with a fan since the plane already has one. If it doesn't, it's a glider and the conveyor would really mess that deal up . . .

 

[QC]

Re: Pilots question

Maybe this is even simpler. The plane is going 100 mph north, so the conveyor goes 100 mph south. The wheels are effectively turning 200 MPH, but the air over the wings is going 100 mph, so voila, the plane flies.

 

[tommays]

Re: Pilots question

As described its a closed loop controled belt with no limits given to the speed or power its has


You really need to see servos moveing around a 5 AXIS milling machine at over 1000" a minute in perfect control AND have the abilty to know when the tool is a bit dull and its time to get a new one from storage before it breaks


Tommays

 

[Haut Medoc]

Re: Pilots question

Is the plane powered with biodiesel? :}

 

[QC]

Re: Pilots question

Reread the rules, I stan_deezy by my interpretation.

Hey, I know, maybe you could use the bio-diesel to make the conveyor runway thing more slipperier :}

 

[jtexas]

Re: Pilots question

The friction of the landing gear on the conveyor should be about the same as it would be on a normal runway. The aircraft has to overcome it's own weight. When it does, and starts to roll forward, the conveyor pulls it back. Increase power, start to move forward, conveyor speeds up, pulls it back again.

Assuming the theoretical conveyor machinery has no upper limit on speed, and the wheel bearings are not magical friction-less bearings, but still have no upper limit on heat tolerance, even at maximum power, all the thrust generated will be used up just fighting the friction caused by the weight of the aircraft on the wheel bearings.

 

[i386]

Re: Pilots question

Hehe, it's a trick question. The first reaction is to assume the plane will remain still. It won't, because thrust moves the plane forward, not the tires. The plane WILL take off. The speed of the conveyor belt is almost irrelevant because forward motion is not transferred to the tires in a plane like in a car.

Now if this was a car it wouldn't be getting anywhere.
If this was a car with some sort of rocket booster it would make headway when the rocket fires.


Back to the plane. Put it in a wind tunnel. Have it pointing into the wind. If the oncoming wind always matches the thrust of the prop(s)/jet(s) it will remain at rest.

 

[QC]

Re: Pilots question

starts to roll forward, the conveyor pulls it back.

Here's where you are messin' up and I am apparently not articulate enough to keep your plane (mind) out of the clouds . . . What does the conveyor pull back on? The wheels obviously, which are not "connected" to the source of propulsion, so it continues to move forward . . . You are assuming that the airplane's engines can only overcome tire and wheel friction, yet somehow they also manage to break the inertia of the thing staying at rest and overcome wind resistance to continue to move forward. What if a couple of wheel bearings were hanging just a little and there was no conveyor? In your world the plane would not move . . .

 

[Bass Man Bruce]

Re: Pilots question

This whole post sounds like something Deejaycee_2000 would actually try!

 

[Bondo]

Re: Pilots question

Ayuh,........

And I guess I got Suckered right from the Start............:/

 

[QC]

Re: Pilots question

I, on the other hand, have not been suckered. I could have to figure this out some day. You don't really know that I won't actually run into this exact problem, and it might be better if I have it figured out first . . . So there.

 

[technostingray]

Re: Pilots question

Have you people ever heard the expression, "spinning your wheels." :duh:

 

[tommays]

Re: Pilots question

QC

It depends on how good the feed back is from the wheel

The most basic one I use puts out 1024 pulses per revolution and the control it connects to can change its mind 10,000 times per second

And for good measure we can put in a few electric eyes to track any movement over the ground

So from My view the airplane wheels never make any ground speed

So when the trick is reveled I will be fooled


Tommays

 

[jtexas]

Re: Pilots question

starts to roll forward, the conveyor pulls it back.

Here's where you are messin' up and I am apparently not articulate enough to keep your plane (mind) out of the clouds . . . What does the conveyor pull back on? The wheels obviously, which are not "connected" to the source of propulsion, so it continues to move forward . . . You are assuming that the airplane's engines can only overcome tire and wheel friction, yet somehow they also manage to break the inertia of the thing staying at rest and overcome wind resistance to continue to move forward. What if a couple of wheel bearings were hanging just a little and there was no conveyor? In your world the plane would not move . . .

I assumed no upper bound on how fast the wheels can spin, but I also assumed the faster they go the more friction is generated, enough to offset engine thrust...did I contradict myself?

Other words, start the treadmill first, it will move the plane.

What if you want to land on the treadmill?

 

[Triton II]

Re: Pilots question

Guys, QC has the right answer assuming friction-free wheel bearings and high pressure tyres.
Just as an aside, I know a pilot who took off from Bodo in northern Norway in a RAF Buccaneer fighter-bomber. The runway was iced up and as he started his run-ups the aircraft started to move immediately. So he floored both engines and took off - with the hand brake on. He discovered his mistake when he landed... bang-bang!

 

[QC]

Re: Pilots question

What if you want to land on the treadmill?

More tire smoke? With the treadmill would be interesting . . . :%

 

[jtexas]

Re: Pilots question

We had a mechanic running up an engine on an icy ramp in Marquette, jumped the chock & slammed into the hangar wall...

 

[steve201]

Re: Pilots question

first off you have to ask this clown..why did you put a aircraft on a conveyor moving X speed..??....when a runway would work better.....

 

[Firestar]

Re: Pilots question

tommays,

Mount that fan to your nose and add 100 bhp . . . You still on the treadmill?

ROFL!!!! Tears came to my eyes.....my side hurts.....TO FUNNY!!!!