Plane Stopped in Midair

"Todd Pattist" wrote

Give her a break, Peter, she asked politely and responded to
the answers.

They only break pete deserves, is from you breaking you finger to get him
into the loony bin. He proves time and time again why this feature is on
most mail readers.
--
Jim in NC


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"WRE" (remove nospam) wrote in message
...
Perhaps the bong you were holding obscured your view.....j/k

Oh, that was funny, and useful, too. Not.
--
Jim in NC


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Peter Duniho wrote:
"Todd Pattist" wrote in message
...

Give her a break, Peter, she asked politely and responded to
the answers.


Yes, she did respond to the answers, refusing to accept them.


It's something that concerned her, and if GA
is to survive, we don't want to be scaring the general
public.


The general public is already scared. For no good reason. That's my point.


The illusion she encountered is quite overpowering.


Most optical illusions are. So what? That's what makes it an *illusion*.
An easily ignored illusion isn't really much of an illusion.


I look at planes every day. Every week I drive by Stewart
where they land the C5A. Its size gives me the same
"stopped in midair" illusion every time I see it. It
always looks like it's just hanging in midair.


But, it is NOT just hanging in midair. It's one thing to ask for expert
advice to confirm one's intuitive sense that an airplane can't just hang in
midair. It's yet another to repeatedly reply that the expert advice is
simply unbelieveable.

I'm getting a little sick and tired of folks who run in a panic every time
they see an airplane doing something they don't understand. "Debbie" has
made very clear that this isn't just about her trying to understand a visual
paradox.

Her *primary* concern is that an airliner might come to a complete stop over
a populated area, and then having done so, fall straight down and kill her.
Statements like "it was quite disturbing", "No fun", "I've been very
concerned", "this bothered me", "the crash would have been extraordinarily
disastrous", and "I'd like to be reassured this is not a common occurrence"
make it very clear where she's coming from, and she's not coming from "I'm
curious about this optical illusion" frame of mind.

Pete


ouch, knew I shouldn't have check back here. Pete, sweetie, you're
overparsing my words. I wasn't running in a panic, I was just trying to
get an explanation for what I saw. At the moment I was trying every
which way to come up with the easy one so I could just shrug the whole
thing off. I couldn't, and spent several hours researching on the Web
before I finally decided to come here. I respect the professional views
provided, and I'm pretty much over it. I love planes, I love to fly, I
don't wear tinfoil hats. Peace out.

Debbie

G.R. Patterson III wrote:


DM wrote:

interesting, but no, it wasn't particularly windy on the ground.


I have the winds aloft forecast for yesterday morning. Where was this?

Phoenix

George Patterson
If a man gets into a fight 3,000 miles away from home, he *had* to have
been looking for it.

Debbie

Dean Wilkinson wrote:

Its called parallax. Your motion, the motion of the plane, and the
background were in the right configuration so that the parallax made the
plane appear to be stationary when in fact it was not...



okay! This is clicking for me, even though I know it may just be another
way of saying "optical illusion". I read this page,

http://en.wikipedia.org/wiki/Parallax

and the concept makes sense to me (not to imply that most everyone
else's explanation didn't).

Debbie

DM wrote:

Phoenix

So much for that idea. Winds at 5,000' above sea level were out of the northwest at 5
knots. At 10,000' they were out of the west at 20 knots. It's unlikely that a 20 knot
headwind made much difference in the appearance of the speed of a large plane.

George Patterson
If a man gets into a fight 3,000 miles away from home, he *had* to have
been looking for it.

"DM" wrote

okay! This is clicking for me, even though I know it may just be another
way of saying "optical illusion". I read this page,

http://en.wikipedia.org/wiki/Parallax

and the concept makes sense to me (not to imply that most everyone
else's explanation didn't).

Debbie

Another thing to keep in mind, is that airplanes work by the laws of
physics. An airplane, be it large or small, can not have zero airspeed for
even an instant, or it will stop flying, and fall out of the air. Given
enough altitude, it can dive, regain airspeed, and start flying again, but
you would have seen that happen, and you did not.

What remains, is the fact that the jet you saw did not stop, and what you
perceived was due to your observation being in error, in some manner.

Have a good one!
--
Jim in NC


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In article ,
says...

yes, I've imagined the whole trig thing. That's why I was looking at the
buildings and other higher geographic markers to get a fix on how it
appeared to be moving relative to those things. Plus, for a moment I was
stopped and pretty much next to it, although of course I was on the
ground and it was probably a couple of thousand feet up or less. And, if
it makes a difference in possible explanations, the plane was headed
east and I was moving west. I'm 99.999% sure it wasn't moving or was
moving very slowly.


You were moving in opposite directions - This is notoriously the most
difficult movement to perceive. The enormous size of the object is the other
factor that confuses our judgement. Sooner or later you are going to have to
accept the 0.001% and admit that you were victim - just as all of us have been
- to an illusion. It's actually a very common illusion, and if it's the first
time you see it, in your frequent drives near that airport, it very well may
not be the last. You must accept that your eye *cannot* reasonably appreciate
the size of the thing. You cannot know how high it is, or how far away it is
or its position relative to ground landmarks or where it would land on the
ground if it were to fall at that instant.

I have seen such illusions many times - but your suggestion that the plane
was stopped, or nearly so, is quite impossible.

G Faris

bOn Thu, 11 Nov 2004 09:10:35 -0700, DM
wrote:

Could
someone here explain how such a thing is possible?

It is indeed possible for an airplane to hover. I saw a Feiseler
Storch (German liaison aircraft of WWII) sit over a runway without
forward motion. Its stall speed of say 30 mph was the same as the wind
speed.

But what you saw was more likely an optical illlusion. The bigger the
aircraft, the slow it seems to move because it is farther from you,
and it is *very* difficult to know how far an airplane is away from
you. I once watched a slow-moving USAF cargo plane searching for
bodies in the water over an inland bay. It appeared to be motionless
because it was twice as large as the planes I usually see land at this
airport.


all the best -- Dan Ford
email: (put Cubdriver in subject line)

Warbird's Forum www.warbirdforum.com
Piper Cub Forum www.pipercubforum.com
the blog www.danford.net

DM wrote:

Her *primary* concern is that an airliner might come to a complete
stop over a populated area, and then having done so, fall straight
down and kill her. Statements like "it was quite disturbing", "No
fun", "I've been very concerned", "this bothered me", "the crash would
have been extraordinarily disastrous", and "I'd like to be reassured
this is not a common occurrence" make it very clear where she's coming
from, and she's not coming from "I'm curious about this optical
illusion" frame of mind.

Pete

ouch, knew I shouldn't have check back here. Pete, sweetie, you're
overparsing my words. I wasn't running in a panic, I was just trying to
get an explanation for what I saw. At the moment I was trying every
which way to come up with the easy one so I could just shrug the whole
thing off. I couldn't, and spent several hours researching on the Web
before I finally decided to come here. I respect the professional views
provided, and I'm pretty much over it. I love planes, I love to fly, I
don't wear tinfoil hats. Peace out.

Debbie

Debbie,
I had a feeling that Pete was overreacting, and I'm glad that you
found the time to respond and clarify your frame of mind. Yes, in fact
I think that most folks on this group are VERY glad that you politely
asked a good question about aviation in one of the most appropriate
newsgroups there are about the subject.

Please don't let some people's overreactions turn you off from this
generally friendly but sometimes rowdy bunch. If you have any more
questions about aviation, or if you just want to learn more about this
whole miraculous invention of flight, I invite you to follow us for a
while, tune out the negative comments, and join the conversation once
again! Who knows, maybe we can convince you that everyone owes it to
themselves to take an introductory flight if they haven't already done
so. If you love planes and you love to fly, you definitely should. A
good spot to start is www.beapilot.com

I hope you join us for a little while longer!

-Aviv