Flight 93 the physics of the impact

[Mynott]

An obvious question is just how many aircraft have crashed with the deliberate intention of doing just that-murder suicide as with Flights 93 and 1771.?

Rare as hens teeth I would say.A fact, as usual ,overlooked by Truthers.

In respect of 93 I would be grateful for further info on Eyewitness accounts at Shanksville that are used by Truthers to illustrate inconsistencies and contradictions about what happened there. Examples are Susan Custer, Jim stop etc and their favorite "chestnut " Susan Mc Elwain.

I have posted this on another thread on 93.,

http://www.internationalskeptics.com/forums/showthread.php?t=236916

 

[Robrob]

An obvious question is just how many aircraft have crashed with the deliberate intention of doing just that-murder suicide as with Flights 93 and 1771.?

Rare as hens teeth I would say.A fact, as usual ,overlooked by Truthers.

Correct. The aircraft on 9/11 were flown at top speed nose first directly into buildings/earth. Without fail, any comparison photos truthers present in defense of their theories will be of aircraft which crash landed - emphasis on the word "landed."

 

[tfk]

In respect of 93 I would be grateful for further info on Eyewitness accounts at Shanksville that are used by Truthers to illustrate inconsistencies and contradictions about what happened there. Examples are Susan Custer, Jim stop etc and their favorite "chestnut " Susan Mc Elwain.

I have posted this on another thread on 93.,

http://www.internationalskeptics.com/forums/showthread.php?t=236916

The most egregiously MISquoted individual associated with Flight 93 has to be, IMO, Wally Miller, the coroner.

Watching truthers contort his statements into "we found no evidence of people at the site" is both laughable & despicable.

 

[Natan]

Correct. The aircraft on 9/11 were flown at top speed nose first directly into buildings/earth.

Yet "twoofers" are ridiculed as twoofers for doubting the official story regarding Flight 93 when the debris of a nearly vertical impact at top speed nose first into earth supposedly is big enough to look like this:

http://www.spiegel.de/img/0,1020,610462,00.jpg

Go figure. The officially sanctioned twoofers also gullibly swallow this:

http://upload.wikimedia.org/wikiped...ight93_bandana.jpg/795px-Flight93_bandana.jpg

I am not into remote controlled planes or nanothermites but I am also not THAT gullible as to believe the official line word for word.

 

[Oystein]

What a singularly bad post, Simon!

Yet "twoofers" are ridiculed as twoofers for doubting the official story regarding Flight 93 when the debris of a nearly vertical impact at top speed nose first into earth supposedly is big enough to look like this:

http://www.spiegel.de/img/0,1020,610462,00.jpg

What's the problem with this?

Go figure. The officially sanctioned twoofers also gullibly swallow this:

http://upload.wikimedia.org/wikiped...ight93_bandana.jpg/795px-Flight93_bandana.jpg

What's the problem with this?

I am not into remote controlled planes or nanothermites

What ARE you into then?

but I am also not THAT gullible as to believe the official line word for word.

Who do you think does "believe the official line word for word"?


In short: Does all and anything you think you know or suspect or doubt about 9/11 converge onto anything that is significantly different from the "official"story?
For example, if you doubt that Flight 93 was steared nose-down into the ground at high speed, do you have another plausible hypothesis what might have happened instead that isn't easily contradicted by evidence you probably already know about AND supported by some evidence? No? Thought so.

 

[NutCracker]

Yet "twoofers" are ridiculed as twoofers for doubting the official story regarding Flight 93 when the debris of a nearly vertical impact at top speed nose first into earth supposedly is big enough to look like this:

http://www.spiegel.de/img/0,1020,610462,00.jpg

Go figure. The officially sanctioned twoofers also gullibly swallow this:

http://upload.wikimedia.org/wikiped...ight93_bandana.jpg/795px-Flight93_bandana.jpg

I am not into remote controlled planes or nanothermites but I am also not THAT gullible as to believe the official line word for word.

Nice sample of the arguments from incredulity that indeed makes truth movement sympathysers look like the fools that they are.

That they tend to consider themselves intellectually superior to others makes them vulnerable to ridicule indeed.

 

[Natan]

What's the problem with this?

What's the problem with this?

Supposedly the results of a near vertical high speed impact.

What ARE you into then?

What facts I know and can believe. Call it 911 agnosticism. I can not believe that is the potential aftermath of a near vertical impact.

Who do you think does "believe the official line word for word"?

Everyone using the term "twoofer" for starters.

For example, if you doubt that Flight 93 was steared nose-down into the ground at high speed, do you have another plausible hypothesis what might have happened instead that isn't easily contradicted by evidence (...)

Yes, a not near vertical impact and/or those "bandanas" being a replica of somesort. Any evidence contradicting that? Mind you, flight data recorders don't suspend impact physics.

 

[MRC_Hans]

Supposedly the results of a near vertical high speed impact.



What facts I know and can believe. Call it 911 agnosticism. I can not believe that is the potential aftermath of a near vertical impact.



Everyone using the term "twoofer" for starters.



Yes, a not near vertical impact and/or those "bandanas" being a replica of somesort. Any evidence contradicting that? Mind you, flight data recorders don't suspend impact physics.

Please enlighten us on your authoritative insights into high speed impact physics.

Hans

 

[Oystein]

Supposedly the results of a near vertical high speed impact.

Yeah - what's your problem there?

I can not believe that is the potential aftermath of a near vertical impact.

You call "facts you know" "agnosticism"? Really??

I guess I'll Stundie that

And a new entry to the Twoofer Dicktshunerie

I can not believe that is the potential aftermath of a near vertical impact.

[ETA] So you think your personal incredulity about events far outside the envelope of your personal experience and expertise bears any weigth and entitles you to call people summarily "gullible"? That's rich. [/ETA]

Everyone using the term "twoofer" for starters.

Got proof? I'd guess you mean that you know at least one person who uses the term "twoofer" AND "believes the official line word for word".

Can you name at least one such person? Then please do so!

For example, if you doubt that Flight 93 was steared nose-down into the ground at high speed, do you have another plausible hypothesis what might have happened instead that isn't easily contradicted by evidence (...)

Yes, a not near vertical impact and/or those "bandanas" being a replica of somesort. Any evidence contradicting that? Mind you, flight data recorders don't suspend impact physics.

I see what you did there: You edited out and replaced with "(...)" the provision "AND supported by some evidence".
I guess that means you are keenly aware that your suppositions are not supported by evidence.

 

[Natan]

Thanks yes that is logical, but the other argument is that the engine bounced? But this can be explained by the angle of impact I think and the velocity of the plane to produce so much momentum on the detached engine.

Bouncing engines:

According to Popular Mechanics, the engine was around 300 yards from the main crash site, and had travelled in the direction the plane was moving.

Jeff Reinbold, the National Park Service representative responsible for the Flight 93 National Memorial, confirms the direction and distance from the crash site to the basin: just over 300 yards south, which means the fan landed in the direction the jet was traveling. "It's not unusual for an engine to move or tumble across the ground," says Michael K. Hynes, an airline accident expert who investigated the crash of TWA Flight 800 out of New York City in 1996. "When you have very high velocities, 500 mph or more," Hynes says, "you are talking about 700 to 800 ft. per second. For something to hit the ground with that kind of energy, it would only take a few seconds to bounce up and travel 300 yards."
ttp://www.popularmechanics.com/science/defense/1227842.html?page=7&c=y

http://www.911myths.com/html/missing_engine.html​

Maximum range of anything on a ballistic path is x = v²/g. For 300 yards or 273.8 meters, given g = 9.81 m/s², this means a lowerbound velocity limit of 51 m/s assuming optimum bounce back angle of 45 degrees. Given an impact speed of 250 m/s according to the official story, this means a plastically deforming metal engine on soft ground would have a coefficient of restitution at an absolute minimum of 51/250 ~= 0.2. For anything other than 45° optimum bounce back angle, you'll soon enough find your Flight 93 engine is behaving like an elastically deforming metal object impacting rubber in a perfect vacuum. Sure.

Any thoughts Hans?

 

[Oystein]

Bouncing engines:

According to Popular Mechanics, the engine was around 300 yards from the main crash site, and had travelled in the direction the plane was moving.

Jeff Reinbold, the National Park Service representative responsible for the Flight 93 National Memorial, confirms the direction and distance from the crash site to the basin: just over 300 yards south, which means the fan landed in the direction the jet was traveling. "It's not unusual for an engine to move or tumble across the ground," says Michael K. Hynes, an airline accident expert who investigated the crash of TWA Flight 800 out of New York City in 1996. "When you have very high velocities, 500 mph or more," Hynes says, "you are talking about 700 to 800 ft. per second. For something to hit the ground with that kind of energy, it would only take a few seconds to bounce up and travel 300 yards."
ttp://www.popularmechanics.com/science/defense/1227842.html?page=7&c=y

http://www.911myths.com/html/missing_engine.html​

Maximum range of anything on a ballistic path is x = v²/g. For 300 yards or 273.8 meters, given g = 9.81 m/s², this means a lowerbound velocity limit of 51 m/s assuming optimum bounce back angle of 45 degrees. Given an impact speed of 250 m/s according to the official story, this means a plastically deforming metal engine on soft ground would have a coefficient of restitution at an absolute minimum of 51/250 ~= 0.2. For anything other than 45° optimum bounce back angle, you'll soon enough find your Flight 93 engine is behaving like an elastically deforming metal object impacting rubber in a perfect vacuum. Sure.

Any thoughts Hans?

English isn't your native language, right? You seem to struggle with reading comprehension.

Here, I looked something up for you in a thesaurus:
tumble (verb)

Definition of TUMBLE
intransitive verb
...
3 : to roll over and over, to and fro, or end over end : toss

This airline accident expert didn't talk about a ballistic flight path. He talks about "moving and tumbling actoss the ground" and "bouncing up and travel". This clerly describes a motion that involves some ballistics, but also some more.



And also, concentrate and reflect on the words "It's not unusual" and "airline accident expert". When an airline accident expert says "it's not unusual", and Simon666 says "I can't believe it", who should I put my money on, and why?

 

[Natan]

You call "facts you know" "agnosticism"? Really??

Fact is you cannot prove or disprove God. That's a fact agnosticists believe. Similarly, I cannot find full proof in the official story nor proof in the conspiracy theories. The best version is still the officially sanctioned one and atheism respectively, I will give you that.

I guess I'll Stundie that

And a new entry to the Twoofer Dicktshunerie

Great, do I win an award for your out of context quoting and interpretation?

[ETA] So you think your personal incredulity about events far outside the envelope of your personal experience and expertise bears any weigth and entitles you to call people summarily "gullible"? That's rich. [/ETA]

Fine. Give me the coefficient of restitution of an elastically deforming (I'm being nice to you) steel ball on soft earth.

 

[Natan]

English isn't your native language, right? You seem to struggle with reading comprehension.

Sure buddy, a near vertical impact will result in a horizontal tumbling and moving across the ground. Conservation of momentum is on your side.

This airline accident expert didn't talk about a ballistic flight path.

You do realize I'm being nice assuming optimum angles? I am a bit mean to not consider multiple bounces but since that is a very rapidly (except for very high coefficients of restitution) exponentially decaying function, it is safe to ignore this. By the way, braking distance for an object on a horizontal path with friction and gravity equals d = V²/ 2gµ. With µ around 0.3 or 0.4 usually, you are not exactly improving your physics case much over V²/g for an optimum ballistic trajectory.

He talks about "moving and tumbling actoss the ground" and "bouncing up and travel". This clerly describes a motion that involves some ballistics, but also some more.

I'm going to be very generous, you can use V² / 2gµ with µ as low as 0.3 or use V²/g sin (2 Theta ) with theta equals 45 degrees. Take your pick.

And also, concentrate and reflect on the words "It's not unusual" and "airline accident expert". When an airline accident expert says "it's not unusual", and Simon666 says "I can't believe it", who should I put my money on, and why?

How about you put your money on exact equations?

 

[Oystein]

The best version is still the officially sanctioned one and atheism respectively, I will give you that.

Good.

But these are not on the same page:

Fact is you cannot prove or disprove God. That's a fact agnosticists believe. Similarly, I cannot find full proof in the official story nor proof in the conspiracy theories.

God is unprovable only to the extemd that it is defined by its adherents as an entity not bound by the physical laws of this universe.

This is not the case with the crash of Flight 93. There is a lot of evidence available on it, and all the evidence converges on it being flown nose-down into the field at high speed: There is the FDR, we have voice recordings from the plane before crash, we have radar of this plane and all planes in it geographical and temporal vicinity, we have debris on the ground assessed by experienced airline crash investigators. All this evidence converges on a single explanation. This explanation is consistent with the overall pattern of events on 9/11 - we know why terrorists abducted the plane, flew it to the Shanksville area, we know why passengers had a motivation to interfere with the hijackers, and it is easy to understand why the hijackers would respond to passenger interference by deliberately crashing the plane.

No such evidence exists for God.

AND you admit that YOU know no evidence for any other theory on 93.

AND neither you nor anyone else has not presented any plausible motives for why someone should have planted the engine or the bandana, or falsified or erred on the flight parameters such as impact angle.

Do you contend that it was NOT flown into the field speeply nose-down at high speed? Then make that claim outright, if you feel you have evidence, and present an alternative.

Mere incredulity is not sufficient.

Great, do I win an award for your out of context quoting and interpretation?

No, you are very unlikely to win this month's Stundie award with this entry - it is too run-of-the-mill for truthers.

Fine. Give me the coefficient of restitution of an elastically deforming (I'm being nice to you) steel ball on soft earth.

Why? Nonsense. See my post above.

 

[Oystein]

Sure buddy, a near vertical impact will result in a horizontal tumbling and moving across the ground. Conservation of momentum is on your side.

Take a fragile toy plane and smash it nearly vertically on the ground, hard enough to cause to break it into many pieces.

Watch the pieces move. Measure how far away from impact location you found them.

Then come back and discuss your observations, with considerations of "Conservation of momentum" included.

Thanks.

You do realize I'm being nice assuming optimum angles? I am a bit mean to not consider multiple bounces but since that is a very rapidly (except for very high coefficients of restitution) exponentially decaying function, it is safe to ignore this.

Unsupported claim.

By the way, braking distance for an object on a horizontal path with friction and gravity equals d = V²/ 2gµ. With µ around 0.3 or 0.4 usually, you are not exactly improving your physics case much over V²/g for an optimum ballistic trajectory.
...
I'm going to be very generous, you can use V² / 2gµ with µ as low as 0.3 or use V²/g sin (2 Theta ) with theta equals 45 degrees. Take your pick.

How about you put your money on exact equations?

All these equations are nonsense if you don't have your model right.
And you have your model wrong.
Again, try it with a toy plane.

 

[Natan]

Take a fragile toy plane and smash it nearly vertically on the ground, hard enough to cause to break it into many pieces.

Watch the pieces move. Measure how far away from impact location you found them.

Then come back and discuss your observations, with considerations of "Conservation of momentum" included.

Wow, your observations are not going to change the equations of motion V² / 2gµ for linear motion along a straight line with friction and V²/g sin (2 Theta) for range of a ballistic arc in vacuum. Interesting you suggest I use observations but am forbidden to use observations of other vertically impacting planes leaving no debris of such size. I guess what's good for the goose ain't good for the gander.

All these equations are nonsense if you don't have your model right.
And you have your model wrong.
Again, try it with a toy plane.

They are optimum cases, ballistic trajectories in vacuum and horizontal movement along a straight line. A real model would be a combination of both and would still go along the lines of something times V²/g for distance traveled. Nice try hand-waving physics away. Keep waving harder and you'll take off unlike your toy airplane.

 

[Dave Rogers]

I see that, in Simon666's world, cylindrical objects cannot roll downhill. No wonder he can't verify any of the events of 9/11, given that he inhabits a different universe to the one they took place in.

Dave

 

[Natan]

I see that, in Simon666's world, cylindrical objects cannot roll downhill. No wonder he can't verify any of the events of 9/11, given that he inhabits a different universe to the one they took place in.

Dave

Where is your hill? I do see trees.

http://home.mindspring.com/~a.lo/Flight_93_Crash_Site.jpg

Also explain to me how a cylindrical object moving at high speed along its axis of revolution will have significant moment transferred to an axis perpendicular to its axis of revolution. It's possible, but only to a certain extent.

 

[Natan]

I'll tell you what. You people drop your model airplanes from rest from 1.5 meters high. V = sqrt (2*g*h). Maximum distance traveled of broken parts, rough estimate V²/g = 2 * h = 3 meters. If you can get your pieces on soft earth to travel more than 3 meters, buy yourself a beer instead of a new airplane.

 

[Sunstealer]

The fan, compressor and turbine sections all rotate perpendicular to the forward direction.