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Establishing Facts Leading To Logical Conclusions, A proposed end to the 'NPT' connundrum

chek
post Dec 19 2007, 06:08 PM
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QUOTE (dMole @ Dec 14 2007, 05:05 AM)
QUOTE (rob balsamo @ Aug 31 2007, 06:16 PM)
speed limits are speed limits, whether taking off from the ground or diving in from the air.

There are 4 forces acting on an aircraft at all times... thrust, weight, lift and drag.

Once you have a thorough understanding of those 4 forces and how they act on an aircraft, you will understand what Joe is saying.

As for "shaking apart", his concerns are very valid. Google such words as control surface flutter, airframe flutter, high speed buffet, mach tuck, coffin corner...

just some to get you started... wink.gif

I posted this over on the UA175 Mach I thread, but most of that has considerable relevance to this thread as well:

http://pilotsfor911truth.org/forum...post&p=10442823

(I don't like Wikipedia AT ALL, but these are good "starter" research topics, and most of my "flow" books are on ["in"compressible] hydrodynamics and ionic plasmas, not air.) Embry-Riddle, MIT, Univ. of Texas, and USAF should all have aerodynamics texts somewhere in their libraries (possibly at other university and USAF or RAF base libraries).

From:
http://en.wikipedia.org/wiki/Supersonic_travel

"Below supersonic speeds the energy radiated to drag is roughly proportional to the square of airspeed and the density of the air. However, as speeds approach the speed of sound, the phenomenon of wave drag appears. This is a powerful form of drag that starts at about Mach 0.8 and ends around Mach 1.2, (transonic speeds). Between these speeds the coefficient of drag (Cd) is approximately tripled. Above the transonic range Cd drops dramatically again, although it remains 30 to 50% higher than at subsonic speeds. This means that a supersonic aircraft has to have considerable extra power to overcome wave drag, although cruising performance above that speed is more efficient."

From:
http://en.wikipedia.org/wiki/Wave_drag

"Wave drag is caused by the formation of shock waves around the aircraft. Shock waves radiate away a considerable amount of energy, energy that is experienced by the aircraft as drag. Although shock waves are typically associated with supersonic flow, they can form at much lower speeds at areas on the aircraft where, according Bernoulli's principle, local airflow accelerates to supersonic speeds over curved areas. The effect is typically seen at speeds of about Mach 0.8, but it is possible to notice the problem at any speed over that of the critical Mach of that aircraft's wing. The magnitude of the rise in drag is impressive, typically peaking at about four times the normal subsonic drag. It is so powerful that it was thought for some time that engines would not be able to provide enough power to easily overcome the effect, which led to the concept of a "sound barrier".

See also:
http://www.centennialofflight.gov/essay/Th...c_Flow/TH19.htm

Here's the book I would probably buy on the subject:
http://www.cambridge.org/catalogue/catalog...21819831&ss=ind

Related:
Bernoulli's Equation
http://www-mdp.eng.cam.ac.uk/library/engin...sis/node38.html

http://www-mdp.eng.cam.ac.uk/library/engin...ysis/node3.html

http://mysite.du.edu/~jcalvert/tech/fluids/bernoul.htm

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

Supercritical turbofan blades could appear to be a "proprietary" R&D-type subject- I didn't find much there.

A good Turbofan tech discussion is at:
http://www.airliners.net/discussions/tech_...ead.main/99101/

What you seem to be overlooking is the employment of wing sweep to delay the onset of the effects of wave drag.

As an example, the two earliest jets were roughly comparable in power and weight classes, but one (which accidentally employed wing sweep for CofG reasons) outperformed the other by a wide margin - the reason being the delaying of the onset of the negative effects of wave drag.

The British Gloster Meteor weighed 8100bs and 3400lbs of thrust and had a top speed of 415 mph.
The German Me262 weighed 8800lbs and 3800lbs of thrust and a top speed of 540 mph, due to the lesser drag penalty of the swept wing.

The B767 uses a sweep angle of 31.5 degrees.
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dMz
post Dec 19 2007, 06:30 PM
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QUOTE (chek @ Dec 19 2007, 03:08 PM)
What you seem to be overlooking is the employment of wing sweep to delay the onset of the effects of wave drag.

...

The B767 uses a sweep angle of 31.5 degrees.

Hello chek,

There is considerably more involved in aerodynamics, ballistics, and hydrodynamics than wing sweep, ogive, and hydrodynamic profile. If I put say, an 85 degree sweep on a pair of wings, that would be great to minimize transonic wave drag right? rolleyes.gif

I figured that this isn't really the proper forum for complex differential flow equations (plus I'd need some valid wind tunnel data and to go get my books at another location). I'd prefer to skip all that in the interests of brevity and availability.

I'll just say that from my experience and education, aerodynamics, ballistics, and hydrodynamics involve considerably more than a protractor angle...
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chek
post Dec 19 2007, 07:49 PM
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QUOTE (dMole @ Dec 19 2007, 10:30 PM)
QUOTE (chek @ Dec 19 2007, 03:08 PM)
What you seem to be overlooking is the employment of wing sweep to delay the onset of the effects of wave drag.

...

The B767 uses a sweep angle of 31.5 degrees.

Hello chek,

There is considerably more involved in aerodynamics, ballistics, and hydrodynamics than wing sweep, ogive, and hydrodynamic profile. If I put say, an 85 degree sweep on a pair of wings, that would be great to minimize transonic wave drag right? rolleyes.gif

I figured that this isn't really the proper forum for complex differential flow equations (plus I'd need some valid wind tunnel data and to go get my books at another location). I'd prefer to skip all that in the interests of brevity and availability.

I'll just say that from my experience and education, aerodynamics, ballistics, and hydrodynamics involve considerably more than a protractor angle...

Agreed - however I still consider the example provided a clear illustration of how that one particular design difference in two otherwise similar contemporary designs accounted for a significant difference in available speed, purely by (accidentally) designing out the drag penalty referred to in a previous post.
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Alan H.
post Jan 5 2013, 01:57 AM
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QUOTE (painter @ Aug 29 2007, 08:27 PM) *
Preface:

I've written elsewhere in this forum that the 9/11 event is very complex set of events and, consequently, one of the problems discussing it is too many things get discussed simultaneously. Even in one thread the evidence/argument counter-argument/counter-counter-argument format can very quickly become overly confusing as more information and increasingly tangential information comes forward. For this reason I would like to suggest a simple way to deal with this problem, especially as it relates to the so called "No Plane Theory," (which, as has been noted elsewhere may be a misnomer).

Establishing Fact to Draw Logical Conclusions:

First, we must agree that in the world we live in some things are possible but not everything is possible. If we agree that material objects behave in ways that correspond to established laws of physics and these material objects are shown behaving in ways that defy these fundamental laws, then we have to conclude that what we are being shown and the explanation given for it must be placed in question.

For example, I believe it can be safely said that most people in this forum agree that it is physically impossible for the upper 10 to 20% of a building such as the WTC towers to 'collapse' in upon the lower 90 to 80% of the structure, crushing it at a rate even remotely close to free fall speed. That we were shown this and given an explanation which defied the laws of both physics and common sense caused many of us to entertain other hypotheses -- such as controlled demolition -- as a more reasonable explanation.

However, we also have to acknowledge that if it is an established fact that the WTC towers cold not have 'collapsed' as we've been led to believe then we are faced with a much broader conspiracy than is commonly believed. In other words, the establishment of this as fact necessarily leads to a logical conclusion -- even without a full grasp of the exact means by which the WTC towers were demolished. If these three buildings can not fall at the rates recorded due to structural failure alone (whatever its initiation may have been), then it must be concluded that some other, as yet unknown, cause was at work and, therefore, conclude the official explanation of the events of 9/11 are false.

Of course, when it is concluded that the official explanation is false, this, logically, leads to many other disturbing questions -- the many levels of who, what, how and why that surround the mystery. These questions can be very interesting and fruitful lines of inquiry. However, they can also, in a way, lead us away from the bare-bones significance of the established conclusion: The official account of what happened on 9/11 is logically and demonstrably false. The point being, we know this as a reasonably and rationally established fact even if we do not know any of the answers to "the many levels of who, what, how and why."

Applying this principal to the so called 'NPT':

That the official explanation for the events of 9/11 can not be true has been established as conclusive -- at least among those of us who have taken the time to study the evidence. We may disagree about the 'means', but the established conclusion holds.

The so called 'NPT' represents a hypothesis concerning one aspect of the 'how' question. Whether the overall 'NPT' is true or false does not change the already established conclusion regarding the official narrative. Nevertheless, this particular question has a bearing of considerable significant consequence because, if it can be demonstrated that the 'NPT' is true (and, therefore, that the assumed 'Real Plane Theory' ['RPT'] is false), then this established fact would substantially impact every aspect of the 9/11 conundrum. If there were no planes, then there were no flights, no hijackers, no passengers, no phone calls, no possible intercepts, no impacts, no resulting fires -- in short, every aspect of the official presentation of 9/11 would be rendered a complete and utter hoax.

The proposition is very simple and precisely the same as was discussed in regards to the way the towers 'collapsed.' If it can be demonstrated that the planes are shown behaving in ways that defy the laws of physics (and are therefore impossible), then it must necessarily be concluded that the planes shown were fake. Again, as before, to establish this conclusively it isn't necessary to show how or even to what extent they were faked. It is simply necessary to establish that what was shown was a physical impossibility.

In another thread, forum member Sure (Jeff) posted a link to a 19min30sec 3.5mb mp3 of a recorded conversation between himself and aerospace engineer Joseph Keith.

Beginning at 14:59 through 16:50, Mr. Keith is recorded as saying the following:



Now, what we have here is an expert in the field stating that what was shown to us is physically impossible. Not being anywhere near an expert myself, I have no way of evaluating the credibility of Mr. Keith's contention (although it does certainly sound plausible to my non-expert opinion). I would think that it would be a fairly easy matter to either confirm or contradict Mr. Keith's contention. We need to ascertain the altitude (easy enough), we need to ascertain the air-speed (calculated by distance covered in frame-rate is one possibility -- but to do that the exact frame rate would have to be known or at least a spread of estimates for various possible video frame rates derived). Finally it would need to be verified by several credible experts that a 767 could not fly at that/those rate(s) at that altitude.

If this can be conclusively shown then all the other questions regarding fakery of the video, how it was faked, who faked it and so forth, even the damage seen at the alleged point of impact, becomes secondary. If we were shown something that is physically impossible, then what we were shown is a deception. If it can be established as a conclusive fact that the material object being observed could not have been flying at that rate at that altitude, then the 'NPT', regardless of all the other questions remaining unanswered, is substantially validated.

Conclusion:

Establishing facts that are conclusive is the most sound, logical and rational method for moving forward -- regardless of the overall implications of the facts established. What matters is the soundness of the established facts.

I invite everyone, but especially pilot and air industry professionals, to comment on this contention by Mr. Keith. I ask that everyone stay on-topic and keep it simple, to the point. Either investigation will uphold Mr. Keith's contention or contradict it. If he is right then 'NPT' is valid, however 'unbelievable' or 'inconvenient' the conclusion may be.

A personal note: I am very busy and absolutely must keep my participation on this forum to a bare minimum. I request that everyone stay on topic, keep it simple, and do not bring any more into the discussion than is necessary to either confirm or refute Mr. Keith's contention.

Thank you.



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Mercurial:
With all due respect, I disagree with your conclusion that because the alleged 767s were operating beyond their normal capacity, it must valiate a "No Plane Theory" if that's what you mean by "NPT." Hundreds of people witnessed planes--of some type--smashing into those towers in NY. I think the only real conclusion you can draw, if what Mr. keith and others have said is true--and it sounds right, from what little I know about the subject--is that the planes that hit the towers were not the AA11 and UA175 767s planes were told they were. What actually hit the towers may have been military planes built for higher speeds at lower altitudes. It is strange that all 4 planes intersected paths & flew over or close to a military airbase, from simulations I've seen of the fight paths. I'm not you're wrong, I just don't think the exeeded capacities of the planes necessarily means there were no planes...If NPT doesn't stand 4 what I thought, well...sorry!
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