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Lift due curvature of the earth?

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Lift due curvature of the earth?

Old 3rd Apr 2013, 19:35
  #21 (permalink)  
 
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Surely "in relation to space" isn't what's relevant though... is it? Wouldn't "in relation to the direction of gravitational force" be more pertinent?
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Old 3rd Apr 2013, 19:38
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Oh, and about the original question: the Russian planes are not supposed to fly by virtue of the rotation of the earth, the fly because of the aerodynamic lift produced by the wings. However, their climb performance is (jokingly) so abysmal, that their height increases mostly because the earth surface curls away from them.
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Old 3rd Apr 2013, 21:40
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And time goes faster at a higher altitude (general relativity), but it goes slower when you're moving (special relativity)! I think ATCast's time calculations are off...
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Old 3rd Apr 2013, 23:57
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Aaaaaaaargh!


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Old 8th Apr 2013, 17:36
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Curvyturistik

This is surely a post for the boffins on Jet Blast, it has a distinct Jet Blast ring to it. Talking of jet blasts and on a more serious note: Do we risk travel sickness due to the speed we are travelling (9oo kts on the EQ)?

Would we all fall over if the Earth suddenly stopped rotating.

Why don`t we build two giant jet engines to power the Earth around space?

We could place little buttons on lamp posts in the street so that people could ring the bell twice when they wanted to get off the Earth and visit a nearby constellation perhaps . . ?

If we are to fly the planet around the universe, would the pilots` licence be regulated by ICAO or would EASA have to stick their noses in?

Would an Earth type rating cost the Earth?

Re: Training. Where would the safest option be for a PFL?

Could we set up a roadside assistance team to repair the Earth in the event of a Terrestrial breakdown?

would it be possible to build special drive-thrus such as a burger joint with Earth size access - how high would the gantry have to be - ? "may I take your order please . .?"

"yes, thanks, 2 billion cheeseburgers, 14,750,000 1/4 pounders with cheese, 2,800,000 apple pies and 3 billion and 4 milkshakes and 200,000,000 coffes please . . ."

""would you like to make those a meal . . ?"

"oh, go on then . . "

"" . . do you want me to supersize that . . ?"

" . .wait a mo, I`ll just ask . . "

RESOUNDING CHORUS

" . . no thanks . ."

"" . Sugar for the coffees . . ?"

" . yeh, we`ll take . . 400,000,000 satchets . . "?"

" . .sorry, make that 399.999.998 as Emily doesn`t take sugar . . "

"" Thank you, that`ll be $34.75 billion and 7 dollars and 75 cents., please . . "

Please leave any countries entire wealth for our charity box
----------`Help Build A Planet`---------

"" . . Can you pay at the next window please, thank you, have a nice light year . .!"

<PA Announcemen>
"Would the Death Star in the parking lot, please make way for our customers, thank you!!"

Last edited by Natstrackalpha; 13th Apr 2013 at 19:52. Reason: 1 million satchets short on the sugar
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Old 8th Apr 2013, 17:48
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The earth spins at approx 1000kts/hr. Concorde flies at approx 1000kts/hr. It takes off from JFK and flies towards LHR which is moving away at the same speed Concord is flying towards it. How does it ever arrive? Equally, it takes off from LHR and flies towards JFK, which is coming towards it at the same speed; i.e. they have a closing speed of 2000kts/hr. So why does it still take 3 hours?
Now I'll put the cork back in the rum bottle and try to stop the house spinning. Hopefully that will cause my brain to slow down too, relatively.
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Old 8th Apr 2013, 17:55
  #27 (permalink)  
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Natstrack - don't forget to pick up a couple of Milky Ways for the kids.

Rat - what I have never understood is how, if the earth is 'stationary' (rotational only) at the poles but moving at 1000kts at the equator, there are not loud rending noises and shearing of the earth's surface - or is that what all these earthquakes are really about?

Leave the cork........................
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Old 8th Apr 2013, 17:57
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What are kts/hr ?
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Old 8th Apr 2013, 17:59
  #29 (permalink)  
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Ask a sailor.
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Old 8th Apr 2013, 19:06
  #30 (permalink)  
 
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...a swing and a MISS!
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Old 8th Apr 2013, 19:25
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Ask a sailor.
Or a very industrious Boy Scout ?
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Old 8th Apr 2013, 20:10
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So if a Hot Air Balloon lifts off on a nil wind day and lands back say after an hour... It wouldn't land on the same spot where it got airborne from ....??
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Old 8th Apr 2013, 20:19
  #33 (permalink)  
 
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somebody is bound to fart and give thrust in one direction. Or perhaps a sneeze, if it's a lady.

You guys are too serious. Much long-haul flying? Strap an aluminium tube to your arse for too many hours and it addles your brain. Metallic osmosis with sweat.

Last edited by RAT 5; 8th Apr 2013 at 20:20.
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Old 9th Apr 2013, 00:59
  #34 (permalink)  
 
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Follow link to previous discussion:

http://www.pprune.org/tech-log/10501...oing-east.html

Last edited by NSEU; 9th Apr 2013 at 01:00.
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Old 9th Apr 2013, 15:28
  #35 (permalink)  
 
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Bucks_raj

Not sure who you are asking the question to, however, making a bunch of assumptions, the simple answer would be no. Consider 24 hours and a spot on the equator. The balloon will have a certain translational speed and if it remains at this speed while increasing height then it has further to go in order to complete one rotation of the earth (larger radius from the earth's centre). So it will land further west than it took off from, the distance being some function of the height above ground and time that the balloon is airborne for.
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Old 10th Apr 2013, 15:36
  #36 (permalink)  
 
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Since someone mentioned "space" earlier in this thread:

With the universe, or a distant star as a reference, the earth doesn't rotate one revolution in 24 hrs, it actually goes a little further (1/365th of a rotation).

Since earth rotates counterclockwise around itself, while travelling counterclockwise around the sun, in one year, it'll have made an extra revolution. You can easily visualize this if you imagine a year only having 4 days, the earth moving one fourth of the way around the sun every day.

The earth's true rotation period (w.r.t. the background stars) is actually 23 hour 56 minutes. This is called the "sidereal" day.

Sidereal time - Wikipedia, the free encyclopedia
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Old 13th Apr 2013, 19:41
  #37 (permalink)  
 
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Smile

No, guys listen, I am sure I`ve got it sussed.

Take a circle . . . .draw a circle. Let this be the Earth, say. Then imagine a point called . . .I dunno, London, say. Now draw a straight line from the centre of the Earth to the point called London. (on the surface of the circle)

Now go, say 50 degrees along the surface and call it 50deg West.

Draw a straight line from the centre of the circle, again to the point called 50deg West. Da-daaa!

See?!? Measure the Earth Surface distance from London to 50deg West, its so many centimetres on your drawing, right?

Now, measure the distance at a higher altitude above the surface, see?

Its further! Because the angle coming out of the centre of the Earth is getting wider and wider all the time . . . .so?

So, to do (60x50=3000) to do 3,000 on the surface is shorter than doing 3000 at a mega high altitude, for these purposes say 35000 feet.

That is why they have found discepencies in the time from London to East Coast of America and they assumed one`s body clock slowed down as we travel along.

ding!

So, had they have travelled at the same speed over the surface (they would have broken the land speed record and their backs!) there would not have been any discrepency in the time thing, thang . . .d`y`get what I mean . . ?

The maths is, even though you are travelling from A to B (London to 50 West) you are in fact travelling further when you are at altitude! So, pretending I cannot do the maths then (which is true) you have to work in dist/sp = T so, if we add more dist then it will take us longer . . . and yet we think we have only traveled from LON to 50W which is true, but we went round the houses to get there, even flying GCT.

So, whaddya say, hmm? The outside of a circle has further to travel than the inside. Its not relative, its simple.

Last edited by Natstrackalpha; 13th Apr 2013 at 20:09.
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Old 13th Apr 2013, 19:49
  #38 (permalink)  
 
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Smile

So if a Hot Air Balloon lifts off on a nil wind day and lands back say after an hour... It wouldn't land on the same spot where it got airborne from ....??
Yeh, it would apart from the odd draft. Why? Because the air in which the balloon is floating is in itself stuck to the Earth by gravity and therefore moves with it, the Earth rotates, the air is stuck to it, the ballon is in the air.

Job done.

Plus free gift!

Also, if there were no air, and you did the balloon trick, apart from it would not float, (or would it - thats another thing) so no air then . . . . . . It, the ballon, is travelling at the same speed as the . . . planet it is sitting on . . right? Yes it is.

Sooooo, if the surface of the planet is rotating at 900 kts/hr then said balloon is also travelling at the same speed, therefore same speed of the surface going up to altitude and same speed at the surface descending back down again. Not relative just ps easy.

Actually, balloon would blow up pretty fantastically, if there were no air . ..

Last edited by Natstrackalpha; 13th Apr 2013 at 20:03.
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Old 13th Apr 2013, 20:02
  #39 (permalink)  
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Originally Posted by DaveReidUK
What are kts/hr ?
It's the new unit proposed to be used for acceleration by the NAECAMISA (North America Except Canada And Mexico International Standards Agency). It was decided that fathoms per forthnight per moment wasn't causing quite enough confusion. With this new unit, it is expected that 97.8% of all interplanetary space probes will be prevented from ever crashing into Mars as they will be on the wrong side of the sun entirely, on a trajectory roughly normal to the ecliptic.
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Old 13th Apr 2013, 20:11
  #40 (permalink)  
 
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Good god, I thought this was going to be a thread about early model A340's....after reading it, I think I need to lie down.
I know, I know . . . , don`t worry, my brain hurts too!
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