Your opinion on this landing

[Sheista]

http://www.thepollspace.com/polls.php?pollid=1359

;)

[B A R R Y[_2_]]

Sheista wrote:
> http://www.thepollspace.com/polls.php?pollid=1359
>
> ;)


It looks like the place is reusable, so it's fine. <G>

[Steven P. McNicoll]

"Sheista" > wrote in message
ups.com...
> http://www.thepollspace.com/polls.php?pollid=1359
>
> ;)
>

Does not appear to have resulted from a landing, looks more like a ground
handling accident.

[Bob Moore]

Sheista wrote
> http://www.thepollspace.com/polls.php?pollid=1359

Photograph had nothing to do with a "landing".

N366PX
The "Ditch Witch" This aircraft was left unchocked in MEM and rolled into
a ditch.

Bob Moore

[Erik]

Sheista wrote:
> http://www.thepollspace.com/polls.php?pollid=1359
>
> ;)
>

I know this already, but it always amazes me to see
the wing holding up the plane. It's propped off of
the ground on the one wing. I know this happens in
the air, it's just neat to see how strong the wings
actually are.

[gatt]

> Does not appear to have resulted from a landing, looks more like a ground
> handling accident.

What do you all figure the ground handler was making per hour?

-c

[Paul Tomblin]

In a previous article, Erik > said:
>Sheista wrote:
>> http://www.thepollspace.com/polls.php?pollid=1359
>>
>> ;)
>>
>
>I know this already, but it always amazes me to see
>the wing holding up the plane. It's propped off of
>the ground on the one wing. I know this happens in
>the air, it's just neat to see how strong the wings
>actually are.

In the air, the load is distributed along the length of the wing, rather
than just on the wing tip. So this wing is taking more torque than a wing
in the air.


--
Paul Tomblin > http://blog.xcski.com/
"Cause geeks like us, baby we can hack the Sun" - Joe Thompson

[Frank Ch. Eigler]

Erik > writes:

> I know this already, but it always amazes me to see
> the wing holding up the plane. It's propped off of
> the ground on the one wing. [...]

As Paul wrote, the loading is different here. But what may be helping
here is that a lot of the force seems to be compressive along the wing
spar(s).

- FChE

[d&tm]

"B A R R Y" > wrote in message
...
> Sheista wrote:
> > http://www.thepollspace.com/polls.php?pollid=1359
> >

> It looks like the place is reusable, so it's fine. <G>

was that a typo or a new definition of a good landing ?(ie only the place ,
not the plane has to be reusable.. :<)
terry

[Matt Whiting]

Sheista wrote:
> http://www.thepollspace.com/polls.php?pollid=1359
>
> ;)
>

There was no landing shown. Parking and landing aren't the same.

Matt

[Matt Whiting]

Paul Tomblin wrote:
> In a previous article, Erik > said:
>> Sheista wrote:
>>> http://www.thepollspace.com/polls.php?pollid=1359
>>>
>>> ;)
>>>
>> I know this already, but it always amazes me to see
>> the wing holding up the plane. It's propped off of
>> the ground on the one wing. I know this happens in
>> the air, it's just neat to see how strong the wings
>> actually are.
>
> In the air, the load is distributed along the length of the wing, rather
> than just on the wing tip. So this wing is taking more torque than a wing
> in the air.

Only if you consider an air load of 1G. I'd have to do that calculation
to be sure, but I'm fairly confident that 4G in the air is more moment
at the wing root than is 1G at the tip.

Matt

[Bertie the Bunyip]

On May 10, 2:47 pm, Sheista > wrote:
> http://www.thepollspace.com/polls.php?pollid=1359
>
> ;)

It wasn't a good one.

Bertie

[B A R R Y[_2_]]

d&tm wrote:
> "B A R R Y" > wrote in message
> ...
>> Sheista wrote:
>>> http://www.thepollspace.com/polls.php?pollid=1359
>>>
>
>> It looks like the place is reusable, so it's fine. <G>
>
> was that a typo or a new definition of a good landing ?(ie only the place ,
> not the plane has to be reusable.. :<)
> terry
>


I always heard it like this:

"Any landing you walk away from is good"
"Any landing where they can reuse the plane is great"

Reusing the PLACE puts a whole 'nuther light on the subject! <G>

[Robert M. Gary]

On May 10, 6:47 am, Sheista > wrote:
> http://www.thepollspace.com/polls.php?pollid=1359
>
> ;)

Certainly couldn't have happened with the energy of a landing with so
little damage. Looks like the line guy may have been pushing it back
and went just a bit too far back. BTW: When on the Kitty Hawk it was
always amazing to me that none of the A-7's ever got pushed off the
deck. They would push them damn close to the edge, often with the
pilot still in it.

-Robert

[Robert M. Gary]

On May 10, 3:20 pm, Matt Whiting > wrote:
> Paul Tomblin wrote:
> > In a previous article, Erik > said:
> >> Sheista wrote:
> >>>http://www.thepollspace.com/polls.php?pollid=1359
>
> >>> ;)
>
> >> I know this already, but it always amazes me to see
> >> the wing holding up the plane. It's propped off of
> >> the ground on the one wing. I know this happens in
> >> the air, it's just neat to see how strong the wings
> >> actually are.
>
> > In the air, the load is distributed along the length of the wing, rather
> > than just on the wing tip. So this wing is taking more torque than a wing
> > in the air.
>
> Only if you consider an air load of 1G. I'd have to do that calculation
> to be sure, but I'm fairly confident that 4G in the air is more moment
> at the wing root than is 1G at the tip.
>
> Matt- Hide quoted text -
>
> - Show quoted text -

I'm not sure how actual aircraft engineers do it but when I got my
engineering degree that isn't how we would do it. Looking at the
moment at the root seems to imply that the entire length of the wing
is of equal strength and the forces are focused on the root. In fact
the wing is not designed to be equal strength throughout, each section
of the wing is only as strong as it needs to be. Therefore, the chance
of failure (at least ideally) is about equal anywhere along the wing
(root, mid section, tip, etc). There may be practical frabrication
reasons why you would have one section of a wing "over engineered",
but in general, that would not be an engineer's goal.

When I was an engineering student we would look at each spar's forces
as a continous function using calc. That way we could use dx to see
the force on any infinite small section of each spar. Looking at the
max force at any dx we could reduce weight (i.e. strength) if one
section was stronger than necessary. The strength at that section
would be designed to meet the requirement of the force expected. I.e.
we wouldn't make the entire wing the same strength if the forces were
not the same throughout.

-Robert

[Jose]

> each section
> of the wing is only as strong as it needs to be. Therefore, the chance
> of failure (at least ideally) is about equal anywhere along the wing

In fact, there's a video somewhere showing a stress test on a wing; the
entire wing fails pretty much at the same time.

Jose
--
Quantum Mechanics is like this: God =does= play dice with the universe,
except there's no God, and there's no dice. And maybe there's no universe.
for Email, make the obvious change in the address.

[Matt Whiting]

Jose wrote:
>> each section
>> of the wing is only as strong as it needs to be. Therefore, the chance
>> of failure (at least ideally) is about equal anywhere along the wing
>
> In fact, there's a video somewhere showing a stress test on a wing; the
> entire wing fails pretty much at the same time.
>
> Jose

I'd like to see that video as the odds of this happening are nearly zero.

Matt

[Robert M. Gary]

On May 12, 11:41 am, Matt Whiting > wrote:
> Jose wrote:
> >> each section
> >> of the wing is only as strong as it needs to be. Therefore, the chance
> >> of failure (at least ideally) is about equal anywhere along the wing
>
> > In fact, there's a video somewhere showing a stress test on a wing; the
> > entire wing fails pretty much at the same time.
>
> > Jose
>
> I'd like to see that video as the odds of this happening are nearly zero.
>
> Matt

Certainly one section would expect to fail first, either by chance or
because one section ends up being weaker for practical reasons. I've
seen the video, when the main spar fails the wing shatters, its a bit
difficult to tell where it failed because of the shattering.

-Robert

[Matt Whiting]

Robert M. Gary wrote:
> On May 12, 11:41 am, Matt Whiting > wrote:
>> Jose wrote:
>>>> each section
>>>> of the wing is only as strong as it needs to be. Therefore, the chance
>>>> of failure (at least ideally) is about equal anywhere along the wing
>>> In fact, there's a video somewhere showing a stress test on a wing; the
>>> entire wing fails pretty much at the same time.
>>> Jose
>> I'd like to see that video as the odds of this happening are nearly zero.
>>
>> Matt
>
> Certainly one section would expect to fail first, either by chance or
> because one section ends up being weaker for practical reasons. I've
> seen the video, when the main spar fails the wing shatters, its a bit
> difficult to tell where it failed because of the shattering.

I've not seen a composite wing fail so maybe they look different than
the metal ones I've seen. The latter always snaps at one point,
typically close to the root. I saw footage some years ago of an
airplane (I want to say an Aero Commander, but I'm not sure anymore)
that pulled up too steeply and shed both wings. They folded up right
near the fuselage on both sides.

I've seen a few videos of airliner wings stressed to failure and when
they fail it looks like a small explosion with debris flying everywhere,
but much of that is the test apparatus flying around. The failure
occurred at a point. It simply isn't possible to design a wing
perfectly enough or, harder yet, assemble it uniformly enough to get a
distributed failure.

Matt

[Jose]

> The failure occurred at a point. It simply isn't possible to design a wing perfectly enough or

Well, yes, but at the time of failure, the rest of the wing (in the test
I saw) was stresesed very close to =its= breaking point, so once it let
go wherever it did, the other points also let go.

Jose
--
Quantum Mechanics is like this: God =does= play dice with the universe,
except there's no God, and there's no dice. And maybe there's no universe.
for Email, make the obvious change in the address.

[mike regish]

They pull those wings up at the tips, no?

mike

"Matt Whiting" > wrote in message
...
>
> I've seen a few videos of airliner wings stressed to failure and when they
> fail it looks like a small explosion with debris flying everywhere, but
> much of that is the test apparatus flying around. The failure occurred at
> a point. It simply isn't possible to design a wing perfectly enough or,
> harder yet, assemble it uniformly enough to get a distributed failure.
>
> Matt

[Jose]

> They pull those wings up at the tips, no?

No. Not in the test I saw. They pull up at various points along the
wing, simulating normal wing loading.

Jose
--
Quantum Mechanics is like this: God =does= play dice with the universe,
except there's no God, and there's no dice. And maybe there's no universe.
for Email, make the obvious change in the address.

[Maxwell]

"Jose" > wrote in message
t...
>> They pull those wings up at the tips, no?
>
> No. Not in the test I saw. They pull up at various points along the
> wing, simulating normal wing loading.
>

This might be the test you recall Jose. I would have to agree it was hardly
a pin-point failure, and certainly not at the root. Seems to be a pretty
good example of a well designed wing.

http://youtube.com/watch?v=6Uo0C01Fwb8

[Robert M. Gary]

On May 13, 8:08 am, Jose > wrote:
> > They pull those wings up at the tips, no?
>
> No. Not in the test I saw. They pull up at various points along the
> wing, simulating normal wing loading.
>
> Jose
> --
> Quantum Mechanics is like this: God =does= play dice with the universe,
> except there's no God, and there's no dice. And maybe there's no universe.
> for Email, make the obvious change in the address.

God doesn't play with dice, his dice just have a lot more sides than
Einstein understood.

-Robert

[Jose]

> This might be the test you recall Jose. I would have to agree it was hardly
> a pin-point failure, and certainly not at the root. Seems to be a pretty
> good example of a well designed wing.
>
> http://youtube.com/watch?v=6Uo0C01Fwb8

No, this wasn't it. What I recall (IIRC) was in German - maybe it was
an Airbus wing. There were three views, I thought I had them on my hard
drive but alas, I don't.

Nonetheless, this one is similar in that the failure happened all at
once, all over.

Jose
--
Quantum Mechanics is like this: God =does= play dice with the universe,
except there's no God, and there's no dice. And maybe there's no universe.
for Email, make the obvious change in the address.

[Matt Whiting]

Jose wrote:
>> The failure occurred at a point. It simply isn't possible to design a
>> wing perfectly enough or
>
> Well, yes, but at the time of failure, the rest of the wing (in the test
> I saw) was stresesed very close to =its= breaking point, so once it let
> go wherever it did, the other points also let go.

Not likely with an aluminum structure. The failure will quickly lessen
the stress on the remaining structure and it will not self-destruct.
I'm still waiting to see the video of this self-destructing wing. I'm
betting it is urban legend, but if there's proof I'd love to see it.

Matt

[Matt Whiting]

Jose wrote:
>> This might be the test you recall Jose. I would have to agree it was
>> hardly a pin-point failure, and certainly not at the root. Seems to be
>> a pretty good example of a well designed wing.
>>
>> http://youtube.com/watch?v=6Uo0C01Fwb8
>
> No, this wasn't it. What I recall (IIRC) was in German - maybe it was
> an Airbus wing. There were three views, I thought I had them on my hard
> drive but alas, I don't.
>
> Nonetheless, this one is similar in that the failure happened all at
> once, all over.
>
> Jose

You need glasses and a hearing aid. At about the 3:27 point the wing is
clearly shown with a kink at one point and the narrator says that the
other wing failed at the same LOCATION (not locations) but wasn't
visible. Sure, some of the skin flew off above the failure point, but
the entire wing didn't even come close to a uniform failure.

Matt

[Morgans[_2_]]

"Matt Whiting" > wrote

> Not likely with an aluminum structure. The failure will quickly lessen
> the stress on the remaining structure and it will not self-destruct. I'm
> still waiting to see the video of this self-destructing wing. I'm betting
> it is urban legend, but if there's proof I'd love to see it.

I remember seeing a show on the making of the 777, and it was in a giant
wing testing rig, and it failed as was predicted at some certain spar
number, but a bunch of the rest blew apart too, since when the one place
failed. all of the stress was transferred to many other locations.

That type of failure is the only way I can see it all failing at the same
time, too.

The odds of the whole wing failing at once is......Astronomical!
--
Jim in NC

[Maxwell]

"Matt Whiting" > wrote in message
...
> You need glasses and a hearing aid. At about the 3:27 point the wing is
> clearly shown with a kink at one point and the narrator says that the
> other wing failed at the same LOCATION (not locations) but wasn't visible.
> Sure, some of the skin flew off above the failure point, but the entire
> wing didn't even come close to a uniform failure.
>

It clearly didn't fail at a single location, and certainly not the root like
you predicted, your trollyness.

Go away, you are starting to sound like MX in drag.

[Jose]

> I'm still waiting to see the video of this self-destructing wing. I'm betting it is urban legend,

IT is not an urban legend. I have seen it.

Well, it's not an urban legend unless I'm also an urban legend. :)

Jose
--
Quantum Mechanics is like this: God =does= play dice with the universe,
except there's no God, and there's no dice. And maybe there's no universe.
for Email, make the obvious change in the address.

[Matt Whiting]

Morgans wrote:
> "Matt Whiting" > wrote
>
>> Not likely with an aluminum structure. The failure will quickly lessen
>> the stress on the remaining structure and it will not self-destruct. I'm
>> still waiting to see the video of this self-destructing wing. I'm betting
>> it is urban legend, but if there's proof I'd love to see it.
>
> I remember seeing a show on the making of the 777, and it was in a giant
> wing testing rig, and it failed as was predicted at some certain spar
> number, but a bunch of the rest blew apart too, since when the one place
> failed. all of the stress was transferred to many other locations.
>
> That type of failure is the only way I can see it all failing at the same
> time, too.
>
> The odds of the whole wing failing at once is......Astronomical!

I agree and that was my point. Having a few sheets of the skin fly off
in close proximity to the spar failure point does not constitute
self-destruction of the week as was claimed earlier. I just watched the
777 video and it is quite clear from both the visual evidence and the
narrators comments that the wing failed at a specific location.

Matt

[Matt Whiting]

Jose wrote:
>> I'm still waiting to see the video of this self-destructing wing.
>> I'm betting it is urban legend,
>
> IT is not an urban legend. I have seen it.
>
> Well, it's not an urban legend unless I'm also an urban legend. :)

You saw something than the video link posted here earlier?

Matt

[Matt Whiting]

Matt Whiting wrote:
> Morgans wrote:
>> "Matt Whiting" > wrote
>>
>>> Not likely with an aluminum structure. The failure will quickly
>>> lessen the stress on the remaining structure and it will not
>>> self-destruct. I'm still waiting to see the video of this
>>> self-destructing wing. I'm betting it is urban legend, but if
>>> there's proof I'd love to see it.
>>
>> I remember seeing a show on the making of the 777, and it was in a
>> giant wing testing rig, and it failed as was predicted at some certain
>> spar number, but a bunch of the rest blew apart too, since when the
>> one place failed. all of the stress was transferred to many other
>> locations.
>>
>> That type of failure is the only way I can see it all failing at the
>> same time, too.
>>
>> The odds of the whole wing failing at once is......Astronomical!
>
> I agree and that was my point. Having a few sheets of the skin fly off
> in close proximity to the spar failure point does not constitute
> self-destruction of the week as was claimed earlier. I just watched the
> 777 video and it is quite clear from both the visual evidence and the
> narrators comments that the wing failed at a specific location.

Not sure how "week" got in there in place of "wing", but you get the
meaning. :-)

Matt

[Jose]

> You saw something [other] than the video link posted here earlier?

Yes. When I find it I'll post it.

As for your comment that

"Having a few sheets of the skin fly off in close proximity to the spar
failure point does not constitute self-destruction of the week",

Nobody is claiming that the wing self destructed. Force was applied.
The claim is that it failed pretty much all at once. And once sheets of
aluminum fall off the wing, the wing is no longer a wing.

Yes, I saw the bent spar.

Jose
--
Quantum Mechanics is like this: God =does= play dice with the universe,
except there's no God, and there's no dice. And maybe there's no universe.
for Email, make the obvious change in the address.

[Matt Whiting]

Jose wrote:
>> You saw something [other] than the video link posted here earlier?
>
> Yes. When I find it I'll post it.
>
> As for your comment that
>
> "Having a few sheets of the skin fly off in close proximity to the spar
> failure point does not constitute self-destruction of the week",
>
> Nobody is claiming that the wing self destructed. Force was applied.
> The claim is that it failed pretty much all at once. And once sheets of
> aluminum fall off the wing, the wing is no longer a wing.

The wing is no longer useful as a wing as soon as the spar breaks.
However, the claim was that the wing was perfectly uniformly strong and
would fail along its entire extent. I claim it will fail in one
location. Quite different.


> Yes, I saw the bent spar.

Then you saw the point failure which I claim is how a wing will always fail.

Matt

[Jose]

> However, the claim was that the wing was perfectly uniformly strong and would fail along its entire extent. I claim it will fail in one location.

No, the claim was =not= that it was perfectly uniformly strong.
The claim was that the strength varied along the length with the
expected loads, so that a failure would be (roughly) equally likely
anywhere along the wing. "Perfection" was not claimed, just "pretty close".

The video =I= saw showed the wing seem to snap at all places at once.
I'm sure slowed-down photography would show a first break and a second
break and all, but it did seem to just explode along its entire length.

>> Yes, I saw the bent spar.
> Then you saw the point failure which I claim is how a wing will always fail.

Yes. This is different from the video I saw (which BTW did not show an
"after" picture where such a failure point would be seen anyway).

Maybe you're right. I'm not an engineer. It just seemed very close.

Jose
--
Quantum Mechanics is like this: God =does= play dice with the universe,
except there's no God, and there's no dice. And maybe there's no universe.
for Email, make the obvious change in the address.

[Matt Whiting]

Jose wrote:
>> However, the claim was that the wing was perfectly uniformly strong
>> and would fail along its entire extent. I claim it will fail in one
>> location.
>
> No, the claim was =not= that it was perfectly uniformly strong.
> The claim was that the strength varied along the length with the
> expected loads, so that a failure would be (roughly) equally likely
> anywhere along the wing. "Perfection" was not claimed, just "pretty
> close".
>
> The video =I= saw showed the wing seem to snap at all places at once.
> I'm sure slowed-down photography would show a first break and a second
> break and all, but it did seem to just explode along its entire length.
>
>>> Yes, I saw the bent spar.
>> Then you saw the point failure which I claim is how a wing will always
>> fail.
>
> Yes. This is different from the video I saw (which BTW did not show an
> "after" picture where such a failure point would be seen anyway).
>
> Maybe you're right. I'm not an engineer. It just seemed very close.

I am an engineer, and the kind of failure you at first described has in
infinitesimal chance of occurring.

Matt

[Maxwell]

"Matt Whiting" > wrote in message
...

> I am an engineer, and the kind of failure you at first described has in
> infinitesimal chance of occurring.
>

Last week you had a BS in Computer Science too.

[Danny Deger]

"Sheista" > wrote in message
ups.com...
> http://www.thepollspace.com/polls.php?pollid=1359
>
> ;)
>

Any landing you can walk away from is a good landing.

Any landing you can taxi away from is a great landing.

I would say this was a good but not great landing.

Danny Deger
www.dannydeger.net

[Orval Fairbairn]

In article >,
"Danny Deger" > wrote:

> "Sheista" > wrote in message
> ups.com...
> > http://www.thepollspace.com/polls.php?pollid=1359
> >
> > ;)
> >
>
> Any landing you can walk away from is a good landing.
>
> Any landing you can taxi away from is a great landing.
>
> I would say this was a good but not great landing.
>
> Danny Deger
> www.dannydeger.net

As I understand it, it was not a landing accident at all! Apparently,
somebody either forgot to set the parking brake or forgot to chock the
plane and it rolled backwards, down the slope, through the fence and
into the waterway.

[Dudley Henriques[_2_]]

Orval Fairbairn wrote:
> In article >,
> "Danny Deger" > wrote:
>
>> "Sheista" > wrote in message
>> ups.com...
>>> http://www.thepollspace.com/polls.php?pollid=1359
>>>
>>> ;)
>>>
>> Any landing you can walk away from is a good landing.
>>
>> Any landing you can taxi away from is a great landing.
>>
>> I would say this was a good but not great landing.
>>
>> Danny Deger
>> www.dannydeger.net
>
> As I understand it, it was not a landing accident at all! Apparently,
> somebody either forgot to set the parking brake or forgot to chock the
> plane and it rolled backwards, down the slope, through the fence and
> into the waterway.



My understanding as well.
DH

[Gatt]

"Orval Fairbairn" > wrote in message
...

> As I understand it, it was not a landing accident at all! Apparently,
> somebody either forgot to set the parking brake or forgot to chock the
> plane and it rolled backwards, down the slope, through the fence and
> into the waterway.

Reminds me of a time I couldn't get a C-172 to track straight down the
taxiway. Kept pulling to the left, and I thought it was the wicked gusting
crosswind we were having.

About the time the wheels left the planet I realized the parking brake was
partially engaged It was the first time I'd ever encountered a situation
where the previous renter had engaged the parking brake...not enough that it
was obvious by the position of the handle, but enough that it caught on the
wheel with the best shoe (Number of Checklist Items = Number of Checklist
Items + 1)

I confessed to the FBO but they weren't worried about the brakes; it was
scheduled for its 100-hour very soon, still had positive braking on both
wheels, and the brake pads were due for replacement anyway. Whew...

-c