Airplane Pilot's As Physicists

"Gatt" wrote in news:13gnvaq8g7a7e25
@corp.supernews.com:


"Bertie the Bunyip" wrote in message
...
"Gatt" wrote in

There goes my Lapin = MX theory. Apologies to Chaud are probably in
order. (I probably apologize?)

nah, standard sock tactic. If his creation looked too much like himself
it'd be too obvious.

Ah, unfortunately I'm not up on sock tactics.




Doesn't matter really. all k00ks are basically the same. Whether they're
the same person or not isn't all that relevant. But it's only natural for
them to start feeling a bit lonely and overwhelmed after a while. And when
the worl doesn't deliver some salvation in the form of a friend, then thye
just invent one!


Bertie

Bertie the Bunyip wrote:
Jim Stewart wrote in news:4-
:

Mxsmanic wrote:
Le Chaud Lapin writes:

If you read carefully, the premise of what they are saying is that, if
you have, for example, a sealed jar with air in it, you are permitted
to consider the air on the _inside_ of the jar, pushing up on the lid
as contributing to a force to lift the jar off the ground, but you are
not allowed to consider the air on the _inside_ of the jar, pushing
down on the jar un the upper surface of the bottom of the jar.
The atmosphere is not a sealed jar. The source of air pressure in the
atmosphere is gravity, not confinement and kinetic energy.
I feel as though I am in the presence of
genius.....


Take a tums, it'll get better

I'd prefer 2 touch-and-go's and a full
stop. I think that will clear my head.

On Oct 9, 4:25 pm, Bertie the Bunyip wrote:
Randy Poe wrote groups.com:





On Oct 9, 4:08 pm, Le Chaud Lapin wrote:
Hi All,

There is a long discussion ongoing in rec.aviation.piloting about
what
causes lift on a plane.

Heh. I know the argument. I think it's broken out here (sci.physics)
many times.

(a) It's the Bernoulli effect due to the shape of the
wing cross-section, the way we were all taught as kids.

(b) No, it's just the angle of attack.

I'm no expert, but I heard enough in similar arguments here
to convince me that the angle-of-attack people are right and
the shape of the wing has more to do with controlling
turbulence.
[snip]

Well, thanks be to god that that';s been authoritatively setttled.

"Authoritatively"? Can you read? Can you read the
part where I said "I'm no expert" and where I said that
I was convinced by other people?

- Randy

On Oct 9, 4:30 pm, Le Chaud Lapin wrote:
On Oct 9, 3:22 pm, Randy Poe wrote:



On Oct 9, 4:08 pm, Le Chaud Lapin wrote:

Hi All,

There is a long discussion ongoing in rec.aviation.piloting about what
causes lift on a plane.

Heh. I know the argument. I think it's broken out here (sci.physics)
many times.

(a) It's the Bernoulli effect due to the shape of the
wing cross-section, the way we were all taught as kids.

(b) No, it's just the angle of attack.

I'm no expert, but I heard enough in similar arguments here
to convince me that the angle-of-attack people are right and
the shape of the wing has more to do with controlling
turbulence.

There are people in the pilot's group, who think that lift on a wing
is analyzed as such:

1. There is air on outside of top of wing that is pushing down, but
reduced because of aerodynamics.
2. The *inside* of the wing contains air pushing up against the
underside of top of wing .

Er... that's a new one. OK, I haven't heard this argument
then.

3. Let us ignore that the same air inside the wing pushes down on the
overside of bottom part of wing.
4. The difference in pressure against the underside of the top wing on
the inside of wing and top of wing on outside, is what gives plane
lift.

You can consider that last just a definition of lift. You
won't get lift unless the upward forces are stronger than
then downward forces.

Note that they ignore the pressure inside the wing that pushes
downward on the wing.

A wing doesn't need to be hollow to fly.

I am trying to convince them that, if there is air on the inside of
the wing, it pushes against all sides of the inside of the wing,
including both top underside and bottom overside, and thereby
nullifying any effect it would have on the wing. Lift is caused by a
difference in pressure between the underside of the bottom of the
wing, and the overside of the top of the wing.

Thanks Randy,

But before we talk about what causes lift on the plane, we should
clear up the basic physics 1st. Note that what I have described above
has nothing to do with airplanes really.

If you read carefully, the premise of what they are saying is that, if
you have, for example, a sealed jar with air in it, you are permitted
to consider the air on the _inside_ of the jar, pushing up on the lid
as contributing to a force to lift the jar off the ground, but you are
not allowed to consider the air on the _inside_ of the jar, pushing
down on the jar un the upper surface of the bottom of the jar.

Sure, there's air pressure inside a sealed jar, but:

(1) Sealed jars sitting on tables don't spontaneously start
flying, and

(2) Conservation of momentum (for every action there's
an equal and opposite reaction) says that you can't push
up from the inside. You'll create a counter force pushing
down.

(3) Solid things fly in wind also.

- Randy

On Oct 9, 1:22 pm, Randy Poe wrote:
On Oct 9, 4:08 pm, Le Chaud Lapin wrote:

Hi All,

There is a long discussion ongoing in rec.aviation.piloting about what
causes lift on a plane.

Heh. I know the argument. I think it's broken out here (sci.physics)
many times.

(a) It's the Bernoulli effect due to the shape of the
wing cross-section, the way we were all taught as kids.

(b) No, it's just the angle of attack.

Probably true, in large part anyway. Just consider that aerobatics
pilots can fly their planes upside-down over considerable distances.
If Bernoulli were the sole factor this couldn't happen.

R.G. Vickson


I'm no expert, but I heard enough in similar arguments here
to convince me that the angle-of-attack people are right and
the shape of the wing has more to do with controlling
turbulence.

There are people in the pilot's group, who think that lift on a wing
is analyzed as such:

1. There is air on outside of top of wing that is pushing down, but
reduced because of aerodynamics.
2. The *inside* of the wing contains air pushing up against the
underside of top of wing .

Er... that's a new one. OK, I haven't heard this argument
then.

3. Let us ignore that the same air inside the wing pushes down on the
overside of bottom part of wing.
4. The difference in pressure against the underside of the top wing on
the inside of wing and top of wing on outside, is what gives plane
lift.

You can consider that last just a definition of lift. You
won't get lift unless the upward forces are stronger than
then downward forces.

Note that they ignore the pressure inside the wing that pushes
downward on the wing.

A wing doesn't need to be hollow to fly.

I am trying to convince them that, if there is air on the inside of
the wing, it pushes against all sides of the inside of the wing,
including both top underside and bottom overside, and thereby
nullifying any effect it would have on the wing. Lift is caused by a
difference in pressure between the underside of the bottom of the
wing, and the overside of the top of the wing.

I count 8-9 people in the group who are utterly convinced that I am
inept at physics, mathematics, etc.

Note that some of these people have been flying aircraft for years,
even decades, while I am still a student pilot.

Comments from anyone who knows physics welcome.

As I said, I lean toward the angle-of-attack arguments now. Take
a flat rectangle, tilt it into the wind. The wind blows against the
front which is also the bottom, not the back/top. So the
forces are on the bottom.

Why does that translate into lift? I forget the exact arguments
but from first principles if the effect is to change the direction
of the incoming air molecules, then by conservation of
momentum that translates into equal and opposite change
of momentum of the surface, i.e. pressure with an upward
component.

- Randy

Jim Stewart wrote in
:

Bertie the Bunyip wrote:
Jim Stewart wrote in news:4-
:

Mxsmanic wrote:
Le Chaud Lapin writes:

If you read carefully, the premise of what they are saying is
that, if you have, for example, a sealed jar with air in it, you
are permitted to consider the air on the _inside_ of the jar,
pushing up on the lid as contributing to a force to lift the jar
off the ground, but you are not allowed to consider the air on the
_inside_ of the jar, pushing down on the jar un the upper surface
of the bottom of the jar.
The atmosphere is not a sealed jar. The source of air pressure in
the atmosphere is gravity, not confinement and kinetic energy.
I feel as though I am in the presence of
genius.....


Take a tums, it'll get better

I'd prefer 2 touch-and-go's and a full
stop. I think that will clear my head.




Fair enough.

bertie

Randy Poe wrote in
ps.com:

On Oct 9, 4:25 pm, Bertie the Bunyip wrote:
Randy Poe wrote
groups.com:





On Oct 9, 4:08 pm, Le Chaud Lapin wrote:
Hi All,

There is a long discussion ongoing in rec.aviation.piloting about
what
causes lift on a plane.

Heh. I know the argument. I think it's broken out here
(sci.physics) many times.

(a) It's the Bernoulli effect due to the shape of the
wing cross-section, the way we were all taught as kids.

(b) No, it's just the angle of attack.

I'm no expert, but I heard enough in similar arguments here
to convince me that the angle-of-attack people are right and
the shape of the wing has more to do with controlling
turbulence.
[snip]

Well, thanks be to god that that';s been authoritatively setttled.

"Authoritatively"? Can you read? Can you read the
part where I said "I'm no expert" and where I said that
I was convinced by other people?


Oow, you ned a sarcasm detector. I can put one up on Ebay for you if you
like.


Bertie

Randy Poe wrote in
ps.com:

On Oct 9, 4:30 pm, Le Chaud Lapin wrote:
On Oct 9, 3:22 pm, Randy Poe wrote:



On Oct 9, 4:08 pm, Le Chaud Lapin wrote:

Hi All,

There is a long discussion ongoing in rec.aviation.piloting about
what causes lift on a plane.

Heh. I know the argument. I think it's broken out here
(sci.physics) many times.

(a) It's the Bernoulli effect due to the shape of the
wing cross-section, the way we were all taught as kids.

(b) No, it's just the angle of attack.

I'm no expert, but I heard enough in similar arguments here
to convince me that the angle-of-attack people are right and
the shape of the wing has more to do with controlling
turbulence.

There are people in the pilot's group, who think that lift on a
wing is analyzed as such:

1. There is air on outside of top of wing that is pushing down,
but reduced because of aerodynamics.
2. The *inside* of the wing contains air pushing up against the
underside of top of wing .

Er... that's a new one. OK, I haven't heard this argument
then.

3. Let us ignore that the same air inside the wing pushes down on
the overside of bottom part of wing.
4. The difference in pressure against the underside of the top
wing on the inside of wing and top of wing on outside, is what
gives plane lift.

You can consider that last just a definition of lift. You
won't get lift unless the upward forces are stronger than
then downward forces.

Note that they ignore the pressure inside the wing that pushes
downward on the wing.

A wing doesn't need to be hollow to fly.

I am trying to convince them that, if there is air on the inside
of the wing, it pushes against all sides of the inside of the
wing, including both top underside and bottom overside, and
thereby nullifying any effect it would have on the wing. Lift is
caused by a difference in pressure between the underside of the
bottom of the wing, and the overside of the top of the wing.

Thanks Randy,

But before we talk about what causes lift on the plane, we should
clear up the basic physics 1st. Note that what I have described
above has nothing to do with airplanes really.

If you read carefully, the premise of what they are saying is that,
if you have, for example, a sealed jar with air in it, you are
permitted to consider the air on the _inside_ of the jar, pushing up
on the lid as contributing to a force to lift the jar off the ground,
but you are not allowed to consider the air on the _inside_ of the
jar, pushing down on the jar un the upper surface of the bottom of
the jar.

Sure, there's air pressure inside a sealed jar, but:

(1) Sealed jars sitting on tables don't spontaneously start
flying, and

(2) Conservation of momentum (for every action there's
an equal and opposite reaction) says that you can't push
up from the inside. You'll create a counter force pushing
down.

(3) Solid things fly in wind also.


You also need a bull**** detector.

I can do that and the sarcasm detector as a deal for you if you like.


Bertie

Ray Vickson wrote in news:1191971717.488856.299560
@g4g2000hsf.googlegroups.com:

On Oct 9, 1:22 pm, Randy Poe wrote:
On Oct 9, 4:08 pm, Le Chaud Lapin wrote:

Hi All,

There is a long discussion ongoing in rec.aviation.piloting about
what
causes lift on a plane.

Heh. I know the argument. I think it's broken out here (sci.physics)
many times.

(a) It's the Bernoulli effect due to the shape of the
wing cross-section, the way we were all taught as kids.

(b) No, it's just the angle of attack.

Probably true, in large part anyway. Just consider that aerobatics
pilots can fly their planes upside-down over considerable distances.
If Bernoulli were the sole factor this couldn't happen.

Bernoulli still works when you're upside down.


Even with a flat bottomed wing..


Doesn't work so good, BTW, which only strengthens the bernoulli
position, but it does work.



Bertie

On Oct 9, 6:15 pm, Randy Poe wrote:
(2) Conservation of momentum (for every action there's
an equal and opposite reaction) says that you can't push
up from the inside. You'll create a counter force pushing
down.

Finally, someone speaks reason.

Now all we need to do is see that the jar might as well be a the
volume of a wing, and the same principle applies.

Not possible to have air on inside of wing pushing up against
underside of top of wing without having same said air pushing downward
on overside of bottom part of wing.

-Le Chaud Lapin-