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But what if an aircraft tried to take off from a conveyor belt . . .

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But what if an aircraft tried to take off from a conveyor belt . . .

Old 21st Apr 2022, 18:31
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But what if an aircraft tried to take off from a conveyor belt . . .

. . . well now we finally have an answer !


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Old 22nd Apr 2022, 11:41
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OK - I'm bored , tired and unable to see the connection between thread title and contents
Any enlightenment available, please ?
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Old 22nd Apr 2022, 11:55
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If you look at the opening sequence, it looks like the a/c is stationary but riding a conveyor belt going in the opposite direction

Well I thought it was fairly amusing to see 'evidence' that would put that old chestnut to bed

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Old 22nd Apr 2022, 12:04
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Sue
It's never a good idea to post ideals the way you see them? I have learned this the hard way!
Hardly anyone sees things the way you see them?
For what it's worth I got it.
But did you notice the change of camera position? I think it slipped on it's mountings?
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Old 22nd Apr 2022, 12:13
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I find it curious that at the start, it sounded a bit like an old farm vehicle, and wondered if an enterprising farmer was towing a recent acquisition, to put on display in his front garden. A popular pastime in placesÖ

Maybe a cousin of Jeremy Clarkson?
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Old 22nd Apr 2022, 13:07
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Ah ! - thank you.
The illusion bit didn't work for me , possibly because I could see the small background strip indicating aircraft movement, Interesting timing, since i have just had a cataract 'sorted', the effect of which ts beyond expectation ! "Don't drive !!!" to 20/20 in just 15 minutes - extraordinary.! The optician offered an aviation related connection - WW 2 airmen suuffering Perspex splinters in their eyes having minimum damage. Interesting !
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Old 22nd Apr 2022, 13:41
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Originally Posted by happyjack View Post
Sue
It's never a good idea to post ideals the way you see them? I have learned this the hard way!

Yes, I'm putting this one in the fail column
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Old 22nd Apr 2022, 20:49
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My mind's-eye is working the same as yours, Sue.

(Not sure if this should bring you any comfort).
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Old 23rd Apr 2022, 10:20
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WW 2 airmen suuffering Perspex splinters in their eyes having minimum damage.
Which I believe is one of the "eureka" moments that made contact lenses possible.........
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Old 23rd Apr 2022, 10:48
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Can a helicopter take off from a spinning turntable?
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Old 23rd Apr 2022, 12:44
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Originally Posted by Peter Fanelli View Post
Can a helicopter take off from a spinning turntable?
Yes but the driver gets frightfully giddy and there is tiny the problem of transferring the rotation of the fuselage to the rotor.
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Old 23rd Apr 2022, 20:42
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but wouldn't you only get giddy due to changes in the rotational speed?

Once you were at a constant speed, would the giddiness stop?
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Old 23rd Apr 2022, 22:09
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Originally Posted by Sue VÍtements View Post
but wouldn't you only get giddy due to changes in the rotational speed?

Once you were at a constant speed, would the giddiness stop?
Not on the roundabouts I have been on unless I shut my eyes, but in any case the rate they of rotation would build steadily.
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Old 24th Apr 2022, 01:02
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Originally Posted by teeteringhead View Post
Which I believe is one of the "eureka" moments that made contact lenses possible.........
Close.
The realisation that perspex fragments in eyes did not cause irritation made intraocular lens implants to replace cataract affected natural lenses possible. I had one done at 27yo.

https://en.wikipedia.org/wiki/Intraocular_lens#History
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Old 25th Apr 2022, 21:41
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Taking off from a conveyor belt is easy. Try landing on one!
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Old 26th Apr 2022, 10:44
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Originally Posted by ChrisVJ View Post
Taking off from a conveyor belt is easy. Try landing on one!
The hardest part must be getting the ac through the doors to find the conveyor belt.
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Old 26th Apr 2022, 14:30
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Originally Posted by teeteringhead View Post
Which I believe is one of the "eureka" moments that made contact lenses possible.........
And modern cataract surgery with artificial lensesÖ
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Old 26th Apr 2022, 14:35
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Originally Posted by Ninthace View Post
The hardest part must be getting the ac through the doors to find the conveyor belt.
The ďMiracle on the HudsonĒ was probably aided by the fact that the tide was going out when they landed on the river, which was heading to the ocean at around six knots at the time, in the same direction as the plane.

If it happened six hours later, the tidal water would have been heading upstream at a similar clip.
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Old 26th Apr 2022, 15:02
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Originally Posted by visibility3miles View Post
The “Miracle on the Hudson” was probably aided by the fact that the tide was going out when they landed on the river, which was heading to the ocean at around six knots at the time, in the same direction as the plane.

If it happened six hours later, the tidal water would have been heading upstream at a similar clip.
My father flew Catalinas and Sunderlands in India during the war and mentioned landing on a river. Obviously, one would want to take off into wind but that aside, is upstream or downstream better? Downstream into wind would give more wind airspeed for a given engine power but upstream would give a shorter run to get up on to the step. Unfortunately he now flies in a better place so I cannot ask him.
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Old 26th Apr 2022, 15:11
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Originally Posted by Ninthace View Post
My father flew Catalinas and Sunderlands in India during the war and mentioned landing on a river. Obviously, one would want to take off into wind but that aside, is upstream or downstream better? Downstream into wind would give more wind airspeed for a given engine power but upstream would give a shorter run to get up on to the step. Unfortunately he now flies in a better place so I cannot ask him.
If you were adrift in the middle of the river, you'd feel an apparent wind which is a vector combination of wind caused by the meteorological wind, and wind caused by the current. Wouldn't you just take off in the direction that was most into that apparent wind?

Edit: Put another way, take the water as your frame of reference. So long as you can avoid hitting the land, its speed and direction are unimportant.
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