Flight 77 obstacles

[TC329]

You do not know where the FDR stopped. If the RADAR ALT is correct, the data stopped over 2800 or more (MORE) feet from the Pentagon. By data stopped, that could mean it was not stored on the chip, not that the data was not in the FDR system! (system, the FDR is made up of many items, and compresses the data to save space on the 1991 CHIP in the FDR, that was not required to meet the standards you can't produce.)

p4t are not rational about the Pentagon, and make up stuff blaming many unknown bad guys in the Air Force, FAA, FBI, and DoD for making the Pentagon blow up. They, p4t, lack the knowledge and ability to live in the real world on 9/11 topics.

Your research is so shallow, you do not back up anything you posted about flight 77 with facts; you have not proven how high the poles, or towers are. Your work is not referenced to anything but bad math. Bad math.

Real bad physics. But par for p4t (learn what acceleration and velocity are) lol

When will you post the standards you keep taking about? Rob should give the copy of the standard, ED-55; was the installed FDR covered by the ED-55 which TSO-124 said earlier FDR did not have to meet? Why are you guys so research challenged? You should look up all the stuff first before you make up false stories and try to mislead others. And the math you guys do will be math class examples of why you should pay attention in math class! No wonder jdx has failed to get the simple ATP FAA rating.

The tower is not 305 feet MSL, it is 92.6 feet MSL. Funny stuff p4t, jdx; FAILURE. Boone looked it up; more research in one day than 9/11 truth in 6 years! LOL p4t are not very good at this stuff.

Beachnut, 92 MSL is 43 feet under the ground where the Antenna stands.

Edited by chillzero: 

Restoring member name.

 

[Anti-sophist]

Let me try to put this back on topic. The "analysis" on pft contains the following lines:

Pole 1 distance to Pentagon = 1016 feet

1016 feet/781 fps = 1.3 seconds

4480 fpm descent needs to be arrested within 1.3 seconds.

75 * 1.3 = 97.5 foot descent within 1.3 seconds.

97.5/32 fps accel due to gravity = 3.0 G's + 1 G = 4.0 G's needed to arrest descent within 1.3 seconds and 97.5 feet vertically. However, 97.5 feet vertically is not available.

The error occurs on the last line.

97.5 feet / 32 (accel due to gravity) does not equal 3.0 Gs.

A height divided by an acceleration does not equal a g-force. No matter what the numbers are, your units are wrong. It's like saying 30 feet divided by 10 seconds equals 3 gallons. Yes.. the numbers are right.. the units are completely wrong.

Fix this error, fix your calculation. Macky/Myriad have been way too kind by doing it for you. That's nonsense as far as I'm concerned. Fix it. Then come back.

 

[Reheat]

....

(1) Flight 77's path took it over the 169ft VDOT antenna;
(2) Flight 77 therefore had to sustain a 4480fpm descent rate to strike the lightpoles on Washington Blvd.
(3) To arrest this descent prior to striking the Pentagon would require a 30.1G pullout (note that the website referred to does not assert this, rather it claims 11.2G)
(4) This is unsustainable by the airframe.

the first premise is dependent on interpreting the FDR data, and without it the entire claim falls apart, you could discuss the other 3 premises, but that would require assiming the first is accurate

Well, that's the problem right there. There is NO PROOF whatsoever of exactly where the aircraft was in relation to the VDOT antenna. Was it over it, beside it, in a bank, hit it, there is no proof.

This new discussion started as a result of trying to prove the aircraft could not hit the poles, subsequently the Pentagon because of the height of the antenna. This only assumed the flight path was OVER the antenna which was not really related to the FDR at all. It was apparently based upon a straight line from beyond the antenna into the Pentagon along the path proven by the Purdue estimated damage path inside the building. It's also sustained by the FDR, but that's beside the point. We have to ASSUME it hit the building in a straight line from the antenna order to know where the aircraft was in relationship to the antenna.

The FDR has been discussed to death and I see no point in continuing along those lines. That discussion is merely a tactic to change the subject from the screwed up math to something else (the FDR data again)......

It does get confusing, doesn't it.....

 

[TC329]

TC329, I need your strict attention.

If you want to talk about flight paths consistent with FDR data, you need to present that data.

You didn't do that. You presented altitude data referenced to ground obstacles. You made a hypothesis based on those obstacles, and you screwed it up royally.

If you want to talk about FDR data, bring some FDR data. But don't complain that my numbers don't work with the FDR data. You set the ground rules. Now you're changing them.

I have no problem showing you how any combination of evidence can be met with a realistic flight path. But you can't hide evidence and claim it doesn't work. That's just stupid.

So far, we've established only two things. First, that there are MANY flight paths that work with the obstacles on the ground -- and given this wide range, there's no reason to doubt one or more solutions also agree with the FDR data. And second, you guys fail at basic Newtonian dynamics. You're in no position to even guess about what happened until you correct this problem.

We can help, but if and only if you're willing to learn.

LMAO...

We're not "hiding the evidence". The FDR data has been available for download since Aug 2006.

You mean you dont have it yet?

 

[Anti-sophist]

LMAO...

We're not "hiding the evidence". The FDR data has been available for download since Aug 2006.

You mean you dont have it yet?

You really don't get it, do you?

You guys set up a mental experiment and performed some math. That math was wrong.

Mackey and Myriad fixed your calculation for you to show you what the true answer of your calculation was. Then you change the subject and say "OH WELL THATS NOT WHAT THE FDR SAYS". So? IT WAS YOUR MENTAL EXPERIMENT.

The topic is your guess at the flight path and the Newtonian physics thereof. You made a post detailing how your guess of the flight path was an impossible flight path for an aircraft. They have showed you that your guess at the flight path is not impossible, just that your math is wrong.

Why are you ignoring the fact that your math is wrong and instead constantly trying to change the subject? This is your experiment, your guess. If it doesn't match the FDR, that's not exactly our problem.

 

[Anti-sophist]

For the record, Mackey and Myriad, you guys made a huge mistake! Heh. This is about the 4th time I've seen someone correct JDX's awful math and watch him refuse to talk about it and instead use it as a wedge to change the subject, shift the burden, etc, etc.

The standard operating debunking procedure for JDX "math" should be to point out the line with the mistake, explain why, and refuse to talk about anything else until it's fixed.

As soon as you produce a "correct" version of a calculation, they'll come up with 1000 ways why "your" version can't be true. Usually involving the FDR. They won't ever understand that it's not "your" version.. it just a mathematically correct version of theirs.

 

[defaultdotxbe]

That discussion is merely a tactic to change the subject from the screwed up math to something else (the FDR data again)......

It does get confusing, doesn't it.....

yeah it does get confusing, expecially since i see this discussion as changing the subject from them being unable to interpret the FDR data properly, but i guess a dog chasing his tail can only go in circles

 

[R.Mackey]

For the record, Mackey and Myriad, you guys made a huge mistake! Heh. This is about the 4th time I've seen someone correct JDX's awful math and watch him refuse to talk about it and instead use it as a wedge to change the subject, shift the burden, etc, etc.

The standard operating debunking procedure for JDX "math" should be to point out the line with the mistake, explain why, and refuse to talk about anything else until it's fixed.

Exactly. TC329, I don't do house calls. If you want to work on the problem, bring it over here.

I've already showed you (and so have several other people) that your work so far is rubbish. You don't seem to be able to absorb it yet, but maybe you will. But we know that whatever information you have, your conclusions are unreliable, because you can't even get velocity and acceleration straight.

So, if you want to bring your question over here -- all of it, FDR data, altitude data, obstacles, whatever -- and work on it, please do so. I'm confident it can be solved. Frankly, I'm surprised that I'm willing to help you at all...

 

[Myriad]

Myriad has the aircraft at 1 G from the VDOT antenna to pole 1 and then pulling 3.2 G's from pole 1 to the pentagon.

Since I was fixing the mistakes in Rob Balsamo's calculation, I used the same trajectory he did: straight line from the VDOT tower to pole 1, and then uniform upward acceleration to the impact point, adjusted to also avoid dropping too low.

The only difference is, I calculated the G forces correctly, and he did not.

So I guess the question remains why doesn't Mackey & Myriad use the altitudes reported in the FDR data?

I used the altitudes Rob Balsamo used in his article. When you posted the article, you didn't mention any criticism of those altitudes. Do you now think they're not valid? If so, then when did you change your mind, and why?

R Mackey numbers make more sense.

Right, because R Mackey didn't follow all of Rob Balsamo's silly assumptions about the trajectory.

However, very different requirements from what the FDR shows. Same with Myriad numbers.

I'm not discussing the FDR in this thread. The trajectory I used is the same one that Rob Balsamo used. You didn't mention any objections to the trajectory he used in his article when you posted it here. In fact, you seemed to approve of the article and uncritically trust the results it reported. In any case, your opinion of Rob's article and the altitude figures he used therein isn't my concern. You can take those up directly with him. I only care that his math is wrong and should be corrected, if he wishes to present an honest case.

R Mackey's or Myriads numbers do not show up in the FDR data at all.

They do show up in Rob Balsamo's article, which claims that a pull-up of over 11 G's is required for the plane to get from pole 1 to the impact point if the plane was descending at 75 fps at pole 1. This claim is false, because the calculations he presents supporting his case have three elementary and significant errors.

With that said, we do thank R Mackey and Myriad for your time critically analyzing the math.

You're welcome.

...and we will be re-checking our calculations and revise the article if required.

We'll see whether any evidence to support this claim appears.

----------

As I've said before, I don't believe that Rob's scenario of a continuous 75 pfs descent from the tower to the pole, followed by a sharp pull-up in the last 1.3 seconds, is a very likely scenario. Let's try a different scenario:

For this analysis, I'll use Rob's time marks which are reasonable: 3.0 seconds from the tower to the pole, and 1.3 seconds from the pole to impact.

For altitudes I'll use 45 msl for the impact hole (Rob's figure), 75 msl for pole 1 (5 feet lower than Rob's number, to make sure it hits), and 314 msl for the tower (10 feet higher than Rob's number, to make sure it misses).

The trajectory I'll use is this: From the tower to the light pole, the plane is descending but is arresting its descent at a constant acceleration. From the light pole to the impact point, the plane descends at a constant vertical velocity.

So, first, the easy part: the descent rate from the pole to the pentagon. A change of -30 feet in 1.3 seconds is -30/1.3 = -23 fps.

Now, from the tower to the pole:

I'll use the formulas for position and velocity of a uniformly accelerating object

position(time t) = pos(initial) + (v(initial) * t) + (1/2 * a * t^2)
velocity(time t) = v(initial) + (a * t)

The knowns are:
velocity(t) = -23 fps (positive is upward)
pos(t) = 75 ft
pos(initial) = 314 ft
t = 3 seconds
...and we need to solve for a.

substituting:
position(time t) = pos(initial) + ((v(time t) - a*t) * t) + (1/2 * a * t^2)

solving for a:
a = 2 * ( p(initial) - p(time t) + v(time t)*t ) / t^2

plugging in the knowns and doing the arithmetic:
a = 2 * ( 314 - 75 + (-23 * 3) ) / 9
a = 37.8 feet/second-second

37.8 / 32 = 1.18

So, the upward acceleration needed to accomplish this maneuver is just under 1.2 g, making the force on the airframe 2.2 G's.

And, this leaves only a steady 1 G descent (no vertical acceleration) for the final 1.3 seconds from the pole to the impact.

Respectfully,
Myriad

 

[Cl1mh4224rd]

Only problem is that JREFers never "corrected" anything.

They've corrected Rob Balsamo/P4T in this very thread. Or did you miss that part?

 

[TC329]

You really don't get it, do you?

You guys set up a mental experiment and performed some math. That math was wrong.

Mackey and Myriad fixed your calculation for you to show you what the true answer of your calculation was. Then you change the subject and say "OH WELL THATS NOT WHAT THE FDR SAYS". So? IT WAS YOUR MENTAL EXPERIMENT.

The topic is your guess at the flight path and the Newtonian physics thereof. You made a post detailing how your guess of the flight path was an impossible flight path for an aircraft. They have showed you that your guess at the flight path is not impossible, just that your math is wrong.

Why are you ignoring the fact that your math is wrong and instead constantly trying to change the subject? This is your experiment, your guess. If it doesn't match the FDR, that's not exactly our problem.

As Mackey and others here do not trust P4T, we do not trust them. Myriad's and Mackeys numbers do not agree. However we do thank them for their time and are reviewing our calculation(s). We apologize if we are not moving fast enough for you.

 

[R.Mackey]

As Mackey and others here do not trust P4T, we do not trust them. Myriad's and Mackeys numbers do not agree. However we do thank them for their time and are reviewing our calculation(s). We apologize if we are not moving fast enough for you.

Oh my god, that's funny.

If you don't trust my numbers, work through the problem yourself. I even set it up for you. I did so because that way, you don't have to trust me. Just do it. Again, any high school kid who's passed algebra should be able to handle it.

If you can't figure out why my numbers and Myriad's are not identical, then you're truly, truly lost.

 

[Jonnyclueless]

How can you expect him to understand the numbers being different when he is simply pasting other people's work as his arguments?

 

[jaydeehess]

Thank you gumboot for that. I was thinking along the same line. However is the lawn area not slightly lower than the floor of the ground level of the Pentagon? If so then the plane could have been at a level that was a foot or so above that of the floor of the Pentagon and still been more than that ASL over the lawn. It would then only need to drop its port wind slightly to have the port engine clip the curb right in front of the building.

At any rate (pun intended), the brain trust at p4t don't understand the difference between velocity and distance.

Its only a step away from killtown math.

 

[jaydeehess]

As Mackey and others here do not trust P4T, we do not trust them. Myriad's and Mackeys numbers do not agree. However we do thank them for their time and are reviewing our calculation(s). We apologize if we are not moving fast enough for you.

3.2 and 3.49 f/s²Well 3.49 is 1.090625 greater than 3.2(I use all the digits my calculator supplies so as not to confuse TC by rounding)

That means that they agree within 10%

Now an acelleration of 11.2 f/s² is 3.5 times greater than 3.2 a difference of 350% yet TC would now like us to believe that when two people work on a problem and round off numbers that they should agree better than 10% while also not admitting that his own calculations being off by 300+% is particularily bothersome to the brain trust of p4t or himself.

 

[beachnut]

Beachy, 92 MSL is 43 feet under the ground where the Antenna stands.

yep, the person who looked up tower told me my mistake, m vs ft, the tower is in meters, then it is 303.8 feet. Wonder if jdx can fix his error in feet per NM?

I have made a conversion error and I am still correct that 77 hit the Pentagon, you made an error in math and physics, and you are still wrong.

I am sorry, I thought since jdx makes big errors he could have messed up the tower height, and I missed the conversion. It is funny, I can make massive errors in everything and 77 still hit the Pentagon. You guys can make up ideas to mislead others and never be correct. How can you be so bad at math on the acceleration stuff? Got Math, got Physics? Math and Physics class 120 bucks per class; internet posting while wine tasting in Sonama on the square, priceless...

 

[Myriad]

TC329, you're in luck. Like R.Mackey, I've made it as easy as possible. In post 24, I followed Rob's calculation step by step, using the same starting values, and fixing each error along the way. The text in bold in post 24 is the changes from the originals. Compare the bold to the original text it replaced, and you'll see all the errors.

Then, in post 54, I showed that the acceleration I calculated does what the article says it's supposed to, which is bring the plane from the light pole at 75 fps descent to the impact point, within the time and vertical distance limits. I also showed how that is done, so you can repeat those calculations yourself, with my calculated acceleration or with any alternative value you want to try.

Then, in post 89 above, I showed a more plausible maneuver that meets the constraints in Rob's scenario, flying over the VDOT tower, below the height of pole 1, and into the impact point, without ever exceeding 2.2 Gs. Thus showing that Rob's calculation, even if he had gotten it right, is irrelevant because he made an unwarranted assumption about how the plane "had to" descend between the tower and the post.

Rob Balsamo's hypothesis that "Arlington Topography, Obstacles Make American 77 Final Leg Impossible" has thereby been falsified several times over. I applaud Rob's diligent efforts to fix the math errors, but I have to say at this point that retracting the whole embarrassing article might be a more honest, and far easier, option.

Respectfully,
Myriad

 

[applecorped]

Ummm......Bush did it.

 

[twinstead]

As Mackey and others here do not trust P4T, we do not trust them. Myriad's and Mackeys numbers do not agree. However we do thank them for their time and are reviewing our calculation(s). We apologize if we are not moving fast enough for you.

Well, if 'reviewing our calculations' is some kind of code for 'figuring out how the hell we are going to get out from under this idiotic theory' then yea--I can see why this is going to take a while.

 

[Reheat]

Well, if 'reviewing our calculations' is some kind of code for 'figuring out how the hell we are going to get out from under this idiotic theory' then yea--I can see why this is going to take a while.

What is really funny is that his article:

"Arlington Topography, Obstacles, AA77 Approach Impossible"

is all over the freaking 'net.

That's worth at least 5 laughing dogs!