I have been getting alot of emails with questions on max speed for 9/11 aircraft. So i decided i will post the reply here and anyone can use the link as they see fit.

Checked

Peter (or any other pilot reading this),

See if you can dig out Vmo for the 76 from a 76 limitations manual (or if you know someone). I need the envelope number.. .not the bird strike number. .sea level to 10,000 (or whatever).

I also just sent an email to some of the other guys to help dig out the number (although they do not check their email often, so it may take awhile).

Im tired of getting distracted by these questions. The "767 cannot exceed 240 mph at 700 AGL" is hogwash. 240 mph is 208 knots. The 767 probably exceeds that on climbout...

Although i agree the reported speeds seem excessive for all the 9/11 aircraft, we need some solid numbers for the 76. We have them for the 75.

I've asked too low, terrain (767 pilot) to post the manual data here.
He is between 2 flights and will try to reply a.s.a.p.

Speed limits B767:

turbulent airspeed: 290kt/.78M
Vmo/Mmo: 360kt/.86M
gear extend: 270kt/.82M
gear retract: 270kt
alternate gear extension: 250kt/.75M
max tyre speed: 225mph (= 196 kt)
min speed above FL250: Vref30+100 kt
min speed for clean LDG: Vref30+50 kt

Greetings
TLT

Good to see you TLT....


thanks for posting the numbers....




(pinned for now)

Danke TLT!


That was quick! Have a nice flight to ZBAA.

Peter

Thanks, Rob. This seems to be a 'burning question' at the moment.

Pilots, please keep in mind that the rest of us do not speak 'aviation'. If anyone has the time to give us a translation that the rest of us can comprehend, it would be greatly appreciated!

Painter,
took me a little time to answer - I am working rather a lot these days.

VMO/MMO = maximum operating limit speed is a speed that may not be deliberately exceeded in any regime of flight (climb, cruise, or descent)

Question: Why are there two speeds, i.e VMO-slash-MMO
Answer: VMO/MMO refers to "Airspeed or Mach Number, whichever is critical at a particular altitude (Remark: Mach no. is usually not calculated below 25,000 ft)

VMO is based on the IAS (indicated airspeed), which is simply speaking measuring the plane's aerodynamic drag.
This aerodynamic drag gets lower in thinner air = on higher altitudes.
A constant indicated airspeed results in a higher Mach number and a higher True Air Speed=TAS, the higher a plane flies.

Examples:

_Alt MSL_IAS__TAS__mph__Mach
___500ft 290kt 290kt 334 0.44
_1,000ft 290kt 296kt 340 0.45
10,000ft 290kt 348kt 400 0.54
25,000ft 290kt 435kt 501 0.72
35,000ft 290kt 493kt 567 0.86 = speed limit

So if a 767 is flying 645 mph at 700 ft MSL see NTSB Report On Ua 175 - thread it is exceeding it's maximum operation limit speed of 360 kt by 55%

_Alt MSL_IAS__TAS__mph__Mach
__ 700ft 360kt 360kt 414 0.54
__700ft 560kt 560kt 645 0.85

Make your own calculations:
Mach Number calculator http://www.grc.nasa.gov/WWW/K-12/airplane/mach.html
True Airspeed calculator http://www.csgnetwork.com/tasinfocalc.html

The other speeds indicated by TLT are self explanatory. Vref has nothing to do with the govt loyalist site, but rather with a calculated take-off speed depending on take-off weight and flaps setting (hope I am correct here).

Final thing: ZBAA is Beijing, just in case you were wondering.



*EDIT* forgot to mention: the fact, that the max. gear retract (extend) speed and the max. speed in turbulent air are considerably lower than Vmo is a clear indication, how 'vulnerable' the airframe can be in case of a speed exceed.

.

I've had a few but don't these two speeds need to be of the same pedigree to arrive at that percentage? Or have I had enough?

Problems with my English or with my maths, Timothy?

Anybody else confused?


645 mph = 560 kts = 1.55 times 360 kts

or 360kts +55% = 560kts = 645 mph



Zap

No, the problem is not yours. It was my lack of comprehension.

_Alt MSL_IAS__TAS__mph__Mach
__ 700ft 360kt 360kt 414 0.54
__700ft 560kt 560kt 645 0.85


Looking back the problem might have been my confusing tables in plain text. I'll have to find a better way to post them.

The ref speed changes constantly during the flight. When you lose weight (burn fuel) the ref speed becomes lower. E.g.. You take off with mtow (186880kg) the Vref30 speed is 176 kt and after e.g. 10 h flight you land with 132000 kg the Vref30 is 139kt that means: minimum clean speed ist Vref30+80kt = 219kt. Thats the lowest speed you can fly wihout using flaps. If your reduce speed below 219kt you have to select flap1, now lowest speed you can fly ist Vref30+60 = 199kt, ... than flap5 lowest speed Vref30+40=179, ... than flap20 lowest speed is Vref30+20=159 (normally you order at this flapsetting gear down) ... than flap30 and lowest speed is Vref30 and you fly the approach at least with vref30+5 in your example 144kt (if there is no headwind component > 5).

I prefer the Boeings!

Thanks for the clarification, TLT

What is your take on the 767 flying far beyond VMO?
How fast can a 767 fly at full throttle? (close to the ground?)

Zap

My question would be...

How could the people responsible for 911 make such a simple mistake as allowing NIST and other organizations come out with speeds exceeding the aircraft's ability?

And since some believe there were no planes (ignoring the fact hundreds of people gathered in crowds to watch the fire burn in tower 1, then witnessed the second plane hit, and the fact not one person has come out to protest the media's coverage and say they were there and saw no plane but saw it on TV later that day) why would they show the cgi aircraft exceeding the aircrafts limits? That makes no sense.

I understand normal pilots don't push the aircraft for safety reasons, but can it be the aircraft was pushed since whom ever was piloting the aircraft (human or computer) didn't care since it was going to be destroyed anyway?

Those who would have been controlling the aircraft, if indeed the air vehicles were as described in the Authorized Version, would have been very concerned not to exceed structural limits for to do so could bring on failure and unpredictable behaviour, missed targets and the negating of any careful preparation of those targets for a plausible (I realize most here consider the official version implausible if not impossible) rationale behind the eventual destruction of those targets by the pre-planned explosive demolition.

Hi all,
My experience having flown Boeings for the last 13 years, 8 on the767 is that Mr.Boeing builds them very strong....
I recall an incident quite some years ago where a Chinese registered B747SP got itself into a spin and fell from 35+ thousand feet to below 10 thousand.
It more than doubled its structural G limits not to mention substantial rolling G (turning whilst pullling G, a definate No No!)
Lost a few panels and gear doors, hydraulic systems etc. and popped a few hundred rivets but kept flying. (By the way they didn't want to report this, but that's another story altogether.)

Where the problem comes I believe (having tried it in the simulator) is ground effect at these high speeds...you just cannot get the a/c to fly with any stability at a few feet off the ground.

Maybe someone with more mathematical ability than me and a good understanding of the physics of ground effect could come up with some numbers to show the significance of ground effect at 460Kts+

Cheers

Transport aircraft are not meant to fly close to the ground, except configured during landing. Flying at that speed that close to the ground would be virtually impossible, or require special equipment such as that Nap of Earth flying, or whatever it's properly called.

"NoE for the DoD," I believe that it's "properly" called, but you may have once cashed a paycheck or two doing exactly that back in SE Asia, I suspect. ;)

Without an autopilot....

Don't know what the approach speed is in these flyby but seems to me going full throttle before the climb begins and maybe someone can give a idication of the reached ground speed at low altitude.


http://www.youtube.com/watch?v=r9DSXVceQKM

It wasn't hani at the yoke...

Good video. I'd say 300-350mph off the back of my head.
I would also opinion that this plane comes in at high throttle, then cuts throttle for the bank up.

As opposed to this video
http://www.youtube.com/watch?v=FwcCiQS_F3A

Which does the opposite, flys in low power, then power up for the fly away.

Both of them are probably 200 feet too high for the light poles.

Another facet of the first video, is how quickly a high speed 757 can climb out of the area, and silently.
Look at this video
http://www.youtube.com/watch?v=fYZOByowrlU

Which appears to be the same plane as simba's link. Note that is a scant 10-15 seconds the 757 is basically gone.


Same Zoom level

Safety: Flight at Excessive Speed
http://www.auf.asn.au/groundschool/flutter.html

Aircraft flight envelope
http://www.auf.asn.au/groundschool/umodule...flight_envelope

and O892's post #30:
http://pilotsfor911truth.org/forum//index....&p=10749560

Critical limiting speeds
http://www.auf.asn.au/groundschool/umodule2.html#critspeeds

Limiting loads and ultimate loads
http://www.auf.asn.au/groundschool/umodule...tml#limit_loads

Just a thought, but having worked at training non jet transport pilots into jets, none have been able to execute high g go arounds and associated manuevers much less this kind of high and low g maneuver successfully.............

I was on youtube checking out cockpit videos etc.. and came across a short video titled 767-200 overspeed. The overspeed alarms cut in and i thought i heard one of the pilots remark '362'?!
The person who uploaded commented-' This was a test flight after a C check. The whole plane started vibrating when he pulled the speed brakes. It was like a stall buffet. I think we at mach .86 when he pulled the speed brakes. He fully extended them too!'
This just corroborates all of the numbers and real world flying experiences all of you guys have been saying.
Here is the link anyway.Apologies if this has already been posted.

<A href="http://www.youtube.com/watch?v=MRbzWQ2r118">http://www.youtube.com/watch?v=MRbzWQ2r118</A>

localbod.

On aircraft (767) speed of the second plane strike. I did a simple D = r x t formula to one of the videos that show the 2nd aircraft approaching. From when its nose is over another building to aprox. its impact is about 7 times its length. I was not sure of the model and a brief search did not turn that up but, from a 767-200 the length is 159', the 767-300, length is 180'. On one video clip that appears to be running at real time speed, I count about 2.5-3.0 seconds. Depending on those seconds and the possible lengths and total distance traveled I came up with about 360-415 mph. I did not figure speed in knots, and did this on the spur very quickly, but was wondering if anyone has done this with perhaps means to be more accurate. Seems a very close determination of speed could be made this way.

The CNN video from the east should lend itself to this kind of time motion study (a la Chandler) and I have wondered why no one has tackled this. The plane length is irrelevant all one needs to do is identify say the nose and track its horizontal movement over time.

Welcome Michael.

300 knots would be 345 statute.

So your numbers sound about right to me. I have long felt that 350 knots would be a reasonable speed for that scenario.

Yes, I have thought of determining speed this way but never sat down to do it. I think you would need the aircraft length though as a measure standard. The 7 lengths totaled 1085' to 1247' from the point its nose was about even with a building to the left (east?) to the tower depending on the model. If I had it on a larger screen and was able to follow it real time and then slow it to measure lengths and know the exact lenght of the aircraft perhaps could pin down very close.

I applaud everyone with "Pilots for 911 Truth". I have been able to get some to look at pilots info and others sites like the architects, but am always amazed at the people who will not take a serious look, but dismiss things without a timely honest investigation.

You can use the side of the twin towers which is 208. Even if the camera is panning to follow the flight the distance (radius) is so far it would hardly matter.

gotcha, thanks.

Just a note:
With each length the plane moves perspective will cause the length to change.
So you need to take perspective into account. Since even a few feet lost in the
measurement can have a dramatic impact on the results.
Otherwise everything sounds just fine.

Well, back to reading.

Dear SanderO

I picked up on the advice that you gave Michael.

I wonder if you would mind turning your mind to a video I have recently placed on Youtube under 23investigator.

The purpose of the video is to consider the length of the aircraft showing in the original 'media video'.
For the purpose of the presentation, the length of the aircraft in the 'media video' has been used, when immediately before impact with Tower Two.
The image has been cut out of the 'media video' and transferred further to the right, so the back of the aircraft aligns with the left corner of Tower Two.
The length of the aircraft 'transferred' is exactly as it shows in the 'media video'.
This in 'reality', would then make the aircraft transferred, to comparison with the face of the Tower Two, shorter than it would be, if perspective could be determined from a vanishing point.

None the less, if the length of the aircraft 'transferred' is compared by ratio to the 208 feet length of the face of Tower Two, it shows as being 'approximately' 180 feet long, obviously longer if perspective was taken into account.
But as you point out to Michael, in the other plane.
With the distance of the camera from the building and the aircraft shown in the 'media video', although in a plane nearly perpendicular to the one you explained to Michael, I would think the difference would be fairly marginal.
But what ever it may be, it would make the aircraft in the 'media video' longer than 180 feet it scales to, by ratio comparison to the face of Tower Two.

At 180 feet, the aircraft in the 'media video' could not be United Airlines Boeing 767 222 N612UA, which was only 160 feet long.

Hope you have time to consider this.

Robert