Can an airplane on a conveyor belt take off? (resolved)

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Christophe
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Re: EELV controversy on aviation and children's dreams (Mayor of Poitiers)




by Christophe » 13/05/21, 21:26

Ahmed wrote:There is friction, obviously, but not really any noticeable power transmission ... Your wheelchair would be fixed with a piece of string that would easily cancel this weak training ...


A piece of string? In which subject ? Because its necessary diameter will depend on the weight of the person occupying the chair ... and the speed of the treadmill ... in short, your "piece of string" may quickly break ...

Mass and speed = friction and grip = power transmission

Then this remark shows that you have not read my example of the bicycle ... therefore go back a few messages! : Cry:
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Re: EELV controversy on aviation and children's dreams (Mayor of Poitiers)




by Petrus » 13/05/21, 22:30

I agree with Ahmed on this point, the carpet cannot compensate for the thrust of the reactors because the friction forces of the wheels are negligible compared to the force produced by the reactors.
The wheels disintegrate long before they can transmit enough force to compensate for the thrust of the engines.
The statement is invalid since the initial hypothesis is false and must therefore be ignored.
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Re: EELV controversy on aviation and children's dreams (Mayor of Poitiers)




by Christophe » 14/05/21, 01:39

You have to stop the alcohol guys ... : Cheesy: : Cheesy: : Cheesy:

The hypothesis is that a device creates an acceleration of the ground which opposes the acceleration of the plane !! Point bar !!

I had written:

an airplane on a conveyor belt (which constantly cancels its ground speed) will he succeed in taking off?

If you have a treadmill problem put that fucking plane in your head on a fucking megatrain with a built-in runway or a fucking hyperdrive skwall-type aircraft carrier or imagine a fucking tailwind in a fucking wind tunnel in the sky. towards...

Holy shit there! : Mrgreen: : Mrgreen: : Mrgreen:

Ahmed if your crazy wheel theory was right you should be able to push a plane or a train just by touching it ... right? We must not have the same conception of the marginal ... : Cheesy: : Lol:
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Re: EELV controversy on aviation and children's dreams (Mayor of Poitiers)




by Ahmed » 14/05/21, 11:58

If an airplane or train had negligible or low mass, a very light push would be enough to move it.
I dispute that the basic premise is relevant: the carpet cannot cancel the speed on the ground (which does not mean anything in this case of figure), from where a debate of the deaf ...
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Re: EELV controversy on aviation and children's dreams (Mayor of Poitiers)




by sen-no-sen » 14/05/21, 13:21

Christophe wrote:
an airplane on a conveyor belt (which constantly cancels its ground speed) will he succeed in taking off?


For an aircraft to be able to take off, its air speed must be sufficient to generate the aerodynamic resultant.
As such, an airplane can very well take off on site with a sufficiently powerful headwind (+ 100Km / h for a rotation speed of 100km / h for example).
In the absence of zero air speed, the aircraft cannot take off.
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Re: EELV controversy on aviation and children's dreams (Mayor of Poitiers)




by Ahmed » 14/05/21, 15:11

In other words, the wind speed, whether relative or absolute, must be greater than the stall speed, a parameter specific to each aircraft.
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Re: EELV controversy on aviation and children's dreams (Mayor of Poitiers)




by Petrus » 14/05/21, 15:38

Christophe wrote:Ahmed if your crazy wheel theory was right you should be able to push a plane or a train just by touching it ... right? We must not have the same conception of the marginal ... : Cheesy: : Lol:

In fact, we are not far from it (at 7m47s if the tag does not work):

In adult version:

There are plenty of other videos like this by searching for "plane pull" on youtube

So yes, compared to the thrust force of the reactors during take-off, the rolling resistance is marginal.

It's interesting how such a short statement can contain two pitfalls.
the first induces confusion between the air / earth reference points and the second is an impossible condition (the belt which compensates for the thrust through free wheels).

In conclusion, I would say that we must doubt everything, especially what is put forward as obvious.
And especially in our current post-truth era.
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Re: EELV controversy on aviation and children's dreams (Mayor of Poitiers)




by Christophe » 14/05/21, 15:40

Petrus wrote:In conclusion, I would say that we must doubt everything, especially what is put forward as obvious.


You couldn't have been very good at math at school! : Cheesy:

A hypothesis of a problem posed to be solved must not be contradicted ! But that's what we've been doing here since the start of this exercise (but I don't blame you: I love the contradiction)

ps: nonetheless, a 5 GW conveyor belt would easily stop one (or 2 or 3) 747s without worries! : Mrgreen:
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Re: EELV controversy on aviation and children's dreams (Mayor of Poitiers)




by Christophe » 14/05/21, 15:47

Petrus wrote:So yes, compared to the thrust force of the reactors during take-off, the rolling resistance is marginal.


Still happy, otherwise no plane could take off! : Shock: : Shock: : Shock:
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Re: EELV controversy on aviation and children's dreams (Mayor of Poitiers)




by Ahmed » 14/05/21, 18:20

The hypothesis of a problem to be solved should not be contradicted!

... unless it is absurd! : Mrgreen:
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