The Miracle Of Flight

Hi all

I was just wondering how airplanes fly in the FE model of the earth? Wouldn't it mean just to get off the ground they would have to be accelerating upwards at an equal force to the acceleration of the earth? 9 m/s^2 or something?

I am a pilot myself and i don't think that my cessna accelerates upwards at this speed, yet it can still fly.

I am not trying to be a smartass (for once) i would just like a fairly comprehensive explanation (or at least a plausible theory).

Thanks

Hi all

I was just wondering how airplanes fly in the FE model of the earth? Wouldn't it mean just to get off the ground they would have to be accelerating upwards at an equal force to the acceleration of the earth? 9 m/s^2 or something?

I am a pilot myself and i don't think that my cessna accelerates upwards at this speed, yet it can still fly.

I am not trying to be a smartass (for once) i would just like a fairly comprehensive explanation (or at least a plausible theory).

Thanks

lol. You aren't a pilot are you?

~D-Draw

lol.  A pilot who doesn't understand lift. 

And he pilots a cessna too. 

Gravity is the apparent effect of pulling you down at 9.8m/sē.
FE acceleration is the effect of the Earth moving torward you at 9.8m/sē.

Both appear as the same effect to one on the surface of the Earth because no frame of reference is given to compare your location or speed with other than Earth.

Flying in RE means you produce upward lift of 9.8 to stay stll and counter gravity.

Flying in FE means you produce upward thrust of 9.8 to accelerate along with the Earth maintaining altitude.

See the Equivalence Principle.

Equivalence principle.  Planes fly just like they do on a RE - by generating lift to keep them off the ground.  This would by like saying 'How can planes take off of a RE when gravity is always pulling them down at 9.8m/s/s?'.  Your plane is accelerating at the 9.8 (well, plus any amount you add with the movement 'upwards' from lift), but you can not see the acceleration caused by the earth's movement as what you have to compare that acceleration to (the earth) looks stationary to you.  Anyway, enough lift = plane off ground

An airplane would not accelerate 9.8m/sē into the air in any observable way. That is merely the lift force required to maintain height above the surface of Earth.

An airplane would not accelerate 9.8m/sē into the air in any observable way. That is merely the lift force required to maintain height above the surface of Earth.

Not into the air, no.  But if you were off the earth, and just measuring the acceleration of the plane, it would appear to be accelerating at a rate greater than 9.8m/s/s.

Quote from: Yiak on November 15, 2007, 02:55:42 PM

An airplane would not accelerate 9.8m/sē into the air in any observable way. That is merely the lift force required to maintain height above the surface of Earth.

Not into the air, no.  But if you were off the earth, and just measuring the acceleration of the plane, it would appear to be accelerating at a rate greater than 9.8m/s/s.

Why would it be accelerating greater than 9.8m/sē if gravity was countering it? A plane producing thrust of 9.8 counters a 'pull' of 9.8 thus remaining at a certain level, no matter what elevation it is at.

Quote from: Mr. Ireland on November 15, 2007, 03:00:17 PM

Quote from: Yiak on November 15, 2007, 02:55:42 PM

An airplane would not accelerate 9.8m/sē into the air in any observable way. That is merely the lift force required to maintain height above the surface of Earth.

Not into the air, no.  But if you were off the earth, and just measuring the acceleration of the plane, it would appear to be accelerating at a rate greater than 9.8m/s/s.

Why would it be accelerating greater than 9.8m/sē if gravity was countering it? A plane producing thrust of 9.8 counters a 'pull' of 9.8 thus remaining at a certain level, no matter what elevation it is at.

I think he's talking about takeoff. You would need to be accelerating greater than 1g in order to get into the air. When you're at preferred elevation, though, then you'd just want the exact 1g to stay level.

~D-Draw

Hmmm. Well I was referring to being stationary relative to Earth, and takeoff isn't... So yeah a greater force would be required to achieve a change to higher altitude.

Thanks to all those who replied sincerely and didnt try and be fucking smart asses

No problem. I know what its like to get replies like that. 

Some of them are like children, can't answer a simple question without passing comment.

Well, if you're going to lie in the first post of the topic how do you expect to be treated?

I don't believe this. Are you actually calling me a liar? On what grounds are you basing this?

Experience.

Ha ha ok i'm sorry lets be friends

I don't believe this. Are you actually calling me a liar? On what grounds are you basing this?

The fact that I am a pilot.  Even when I was a n00b pilot I knew the plane had to accelerate upwards.

did i ever say the plane never accelerated upwards? i just didnt know it accelerated at 9.8m/s. I looked through my theory book and it never had that equation in it. But i still have my pilots license, i guess down here in Aus gravity doesnt exist.

I'm also a pilot, damn good one according to MS Flight Simulator

lol.  That's about the only way paradiselost would've been in a Cessna. 

how do you know this? What proof do you have that i don't fly planes?

Quote from: Yiak on November 15, 2007, 03:07:56 PM

Quote from: Mr. Ireland on November 15, 2007, 03:00:17 PM

Quote from: Yiak on November 15, 2007, 02:55:42 PM

An airplane would not accelerate 9.8m/sē into the air in any observable way. That is merely the lift force required to maintain height above the surface of Earth.

Not into the air, no.  But if you were off the earth, and just measuring the acceleration of the plane, it would appear to be accelerating at a rate greater than 9.8m/s/s.

Why would it be accelerating greater than 9.8m/sē if gravity was countering it? A plane producing thrust of 9.8 counters a 'pull' of 9.8 thus remaining at a certain level, no matter what elevation it is at.

I think he's talking about takeoff.

Yes.  I really need to explain myself better...

check out the great circle route thread...could someone explain that?

how do you know this? What proof do you have that i don't fly planes?

You don't know that the you have to accelerate faster than 1g to get off the ground. Everyone should know that, even if they're not pilots, but if you're flying a plane, you should know exactly what 1g is. It only makes sense. That and lots of people come in here saying they're pilots (surprisingly, most of them say they fly cessnas as well...)


~D-Draw

i notice you don't have an explanation for the great circle route...

You're right, I don't. Mmmm, sweet irrelevance.


~D-Draw

I am a pilot myself and i don't think that my cessna accelerates upwards at this speed, yet it can still fly.

I'm a  B-52 Stratofortress pilot of the U.S. Air Force. I bomb Iraqis every Tuesday with my plane.

Quote from: paradiselost on November 15, 2007, 02:47:40 PM

I am a pilot myself and i don't think that my cessna accelerates upwards at this speed, yet it can still fly.

I'm a  B-52 Stratofortress pilot of the U.S. Air Force. I bomb Iraqis every Tuesday with my plane.

Love shack...baby, love shack.


~D-Draw

Hi all

I was just wondering how airplanes fly in the FE model of the earth? Wouldn't it mean just to get off the ground they would have to be accelerating upwards at an equal force to the acceleration of the earth? 9 m/s^2 or something?

I am a pilot myself and i don't think that my cessna accelerates upwards at this speed, yet it can still fly.

I am not trying to be a smartass (for once) i would just like a fairly comprehensive explanation (or at least a plausible theory).

Thanks

LOL, liar.
Planes generate lift equal to gravity/UA.  If they did not, they would not be able to lift off the ground.