What hit the pentagon on 9/11/01?

reply to post by turbofan

Let's try again, what is the EAS at ALTITUDE (35,000 feet)!?

You are hung up on this, and not understanding.

I have already told you that AT SEA LEVEL the IAS, EAS and TAS are almost exactly the same.

Of course, at FL 350 you will not see 462 Kts on the airpeeed indicator.

Because, DUE TO THE ALTITUDE (and really, the temperature) it calculates out to above Mach 1.


Let's see if I can, once more, explain it with some help from www.aerospaceweb.org...

Here, an education for everybody:

Another source of error in airspeed measurement is independent of the measuring instruments but due to an aerodynamic effect called compressibility. When flying faster than about 200 knots, the air being rammed into the pitot tube becomes compressed or squeezed to a higher pressure than it would if the fluid were an ideal incompressible substance. This compressibility error increases the faster the aircraft flies and grows particularly large near Mach 1.

Like instrumentation error, the compressibility error can also be accounted for using an airspeed correction chart. The result of this correction is the equivalent airspeed (EAS). The faster and higher an aircraft flies, the larger the correction becomes and the greater the difference between CAS and EAS. Equivalent airspeed is defined as the speed at sea level that would produce the same dynamic pressure as the true airspeed at the altitude the vehicle is flying at.

For example, if a plane is flying at 500 KTAS (Knots True Air Speed) at 20,000 ft, the true dynamic pressure is 451 lb/ft² and the equivalent airspeed is 365 KEAS (Knots Equivalent Air Speed). Conversely, a true airspeed of 365 KTAS at an altitude of 0 ft results in a dynamic pressure of 451 lb/ft².

PLEASE take note, in that example. It implicity says that AT SEA LEVEL KTAS and KEAS are essentionally the same.

Anyone who uses a calculator to convert IAS to TAS will find that the TAS at seal level is essentially the same as indicated.

(BTW...the term 'calibrated' airspeed is simply a precise way to say that it is indicated corrected for internal instrument errors. Typical errors are in the range of just a few knots...)

However, the indicated airspeed is not always completely accurate. Errors are often introduced by the design of the measuring instruments, lag in the time it takes for the system to update, or the location of the pressure probes on the aircraft. Although these errors are typically small, they can introduce discrepancies as large as several knots. The most significant source of instrumentation error is that due to the position of the pitot-static probes. This type of error tends to vary primarily with speed and angle of attack since it is difficult to find a location on an aircraft that will always measure static pressure correctly at all combinations of these variables. The position error is usually greatest at low speeds and high angles of attack, like those encountered during takeoff and landing, but smallest during cruise flight.

AND...

Calibrated airspeed is defined as the indicated airspeed corrected for instrumentation errors in the pitot-static pressure measurement system. Many modern aircraft correct for these errors internally and automatically display the CAS, instead of IAS, on the airspeed indicator gauge.

Regardless, the instrumentation errors are typically small such that IAS and CAS are very close.

Back to TAS/EAS:

...Another approach to estimate the true airspeed is a rule of thumb technique based on the indicated airspeed and altitude. In this approach, the pilot simply increases the IAS by two percent for every thousand feet of altitude to approximate the TAS. You can perform many of these airspeed conversions yourself using the Atmospheric Properties Calculator on this site.

I can't get the charts and graphs to come into this post.

If you look at the graph, you will see the bottom line, level, indicating sea level...along that line is the CAS. The graph then has the various altitude lines drawn in, so you can use it to correct (by speed and altitude) for compressiblity effects. Example, using the chart: At 500 KCAS and 5,000 feet ASL the compressibility adjustment is -7 knots to give you the KEAS. Hardly worth mentioning,now is it???

It also has a convenient Mach 1 curve....so by working the chart in a different direction, you can see that Mach 1, at 35,000 feet (these all assume STANDARD TEMPS...since Mach speed is affected by temperature AND density). Where was I? Oh, yes..Mach 1 at 35,000 feet plots to about 350 KCAS.

Here, they provide a calculator for you to experiment with values and see for yourself.
___________________________________________________________

For your viewing pleasure, I inputed 462 KCAS at sea level:

True Airspeed ----- 462
Calibrated Airspeed ----- 462
Equivalent Airspeed ----- 462
Airspeed Compressibility Correction ----- 0
Mach Number -------- 0.6984
Equivalent Mach Number ------ 0.6984












[edit on 27 September 2009 by weedwhacker]

reply to post by weedwhacker


No sir, YOU are misunderstanding and overlooking the significance
of EAS!

It matters not what the mach number is at sea level becase your
conversion factors in air density.

What does matter is the equivalent speed at altitude indicating that
your 767 is capable of breaking the sound barrier!

This is physically impossible!

The effect of dynamic air pressure at sea level means that at 510 Knots,
the aircraft is encountering the same forces as it would at 35,000 feet
traveling over MACH 1!

Now ask yourself if this is even possible while you reference Egypt air
which broke apart at mach 0.99 at 22,000 feet!!!

You expect a 767 to stay intact at sea level moving 510 Knots?

Do you see a problem here Weed?

Let me tell you the three strikes once again:

- Air frame intergrity
- Available power to reach speed
- Controlled flight

All of these factors go out the window above VMo. Maybe not all at once,
and maybe not at 10, or 30, or 50 knots over VMo...but PLEASE don't
tell me you expect a 767 which is exceeding VMo By 150 FREAKIN' KNOTS at SEA LEVEL is going to be:

- stable in a controlled manner
- withstand extreme structural stress
- have the engine power to reach speeds which it cannot reach at 35,000 feet in thinner, less dense air.

IMPOSSIBLE!


Futhermore, don't tell me a rookie pilot could grace a giant slug into a
small target when fighter pilots have trouble doing this in precision
aircraft with thousands of hours under their belt.




[edit on 27-9-2009 by turbofan]

I've been doing some soul searching lately perhaps I too haven't been critical and skeptical enough over some of the claims made by the truth movement . However I still feel something isn't right about the official story . Here's a site I've been checking out regarding the commission .

www.911proof.com...

[edit on 27-9-2009 by OpusMarkII]

reply to post by turbofan


I don't think you are actually reading the material.

Again, the forces in one example:

For example, if a plane is flying at 500 KTAS (Knots True Air Speed) at 20,000 ft, the true dynamic pressure is 451 lb/ft² and the equivalent airspeed is 365 KEAS (Knots Equivalent Air Speed). Conversely, a true airspeed of 365 KTAS at an altitude of 0 ft results in a dynamic pressure of 451 lb/ft².

You are (incorrectly) making a claim about KEASthat is completely unsupported by science.

Your grasp on the subject is lacking.

AND....Mach number IS important. AND....Egypt Air 990 breking apart is misdirection in this discussion.

You see...regardless, THAT flight was at Mach 1 (well, 0.99).

Doesn't matter how much you want it to be ture, American Airlines 77, at near sea level, and indicated 462 knots is NOT near Mach 1. What the airplane "feels", and the aerodynamic forcesa at work, is explained very well, in the material---I've tried layman's terms, that didn't work for you. SO, now you should read and learn....

Did you even visit the website????
_____________________________________________________

And, again....American Airlines 77 did not exceed VMO until the very end. If you honestly believe that the airplane is so fragile that it will disintegrate within less than 30 seconds just from accelerating past VMO...then you seriously misunderstand just how strong the airplane is.




[edit on 27 September 2009 by weedwhacker]

Originally posted by weedwhacker
reply to post by turbofan

 

Let's try again, what is the EAS at ALTITUDE (35,000 feet)!?

You are hung up on this, and not understanding.

I have already told you that AT SEA LEVEL the IAS, EAS and TAS are almost exactly the same.

Of course, at FL 350 you will not see 462 Kts on the airpeeed indicator.

Because, DUE TO THE ALTITUDE (and really, the temperature) it calculates out to above Mach 1.


Let's see if I can, once more, explain it with some help from www.aerospaceweb.org...

Here, an education for everybody:

Another source of error in airspeed measurement is independent of the measuring instruments but due to an aerodynamic effect called compressibility. When flying faster than about 200 knots, the air being rammed into the pitot tube becomes compressed or squeezed to a higher pressure than it would if the fluid were an ideal incompressible substance. This compressibility error increases the faster the aircraft flies and grows particularly large near Mach 1.

Like instrumentation error, the compressibility error can also be accounted for using an airspeed correction chart. The result of this correction is the equivalent airspeed (EAS). The faster and higher an aircraft flies, the larger the correction becomes and the greater the difference between CAS and EAS. Equivalent airspeed is defined as the speed at sea level that would produce the same dynamic pressure as the true airspeed at the altitude the vehicle is flying at.

For example, if a plane is flying at 500 KTAS (Knots True Air Speed) at 20,000 ft, the true dynamic pressure is 451 lb/ft² and the equivalent airspeed is 365 KEAS (Knots Equivalent Air Speed). Conversely, a true airspeed of 365 KTAS at an altitude of 0 ft results in a dynamic pressure of 451 lb/ft².

PLEASE take note, in that example. It implicity says that AT SEA LEVEL KTAS and KEAS are essentionally the same.

Anyone who uses a calculator to convert IAS to TAS will find that the TAS at seal level is essentially the same as indicated.

(BTW...the term 'calibrated' airspeed is simply a precise way to say that it is indicated corrected for internal instrument errors. Typical errors are in the range of just a few knots...)

However, the indicated airspeed is not always completely accurate. Errors are often introduced by the design of the measuring instruments, lag in the time it takes for the system to update, or the location of the pressure probes on the aircraft. Although these errors are typically small, they can introduce discrepancies as large as several knots. The most significant source of instrumentation error is that due to the position of the pitot-static probes. This type of error tends to vary primarily with speed and angle of attack since it is difficult to find a location on an aircraft that will always measure static pressure correctly at all combinations of these variables. The position error is usually greatest at low speeds and high angles of attack, like those encountered during takeoff and landing, but smallest during cruise flight.

AND...

Calibrated airspeed is defined as the indicated airspeed corrected for instrumentation errors in the pitot-static pressure measurement system. Many modern aircraft correct for these errors internally and automatically display the CAS, instead of IAS, on the airspeed indicator gauge.

Regardless, the instrumentation errors are typically small such that IAS and CAS are very close.

Back to TAS/EAS:

...Another approach to estimate the true airspeed is a rule of thumb technique based on the indicated airspeed and altitude. In this approach, the pilot simply increases the IAS by two percent for every thousand feet of altitude to approximate the TAS. You can perform many of these airspeed conversions yourself using the Atmospheric Properties Calculator on this site.

I can't get the charts and graphs to come into this post.

If you look at the graph, you will see the bottom line, level, indicating sea level...along that line is the CAS. The graph then has the various altitude lines drawn in, so you can use it to correct (by speed and altitude) for compressiblity effects. Example, using the chart: At 500 KCAS and 5,000 feet ASL the compressibility adjustment is -7 knots to give you the KEAS. Hardly worth mentioning,now is it???

It also has a convenient Mach 1 curve....so by working the chart in a different direction, you can see that Mach 1, at 35,000 feet (these all assume STANDARD TEMPS...since Mach speed is affected by temperature AND density). Where was I? Oh, yes..Mach 1 at 35,000 feet plots to about 350 KCAS.

Here, they provide a calculator for you to experiment with values and see for yourself.
___________________________________________________________

For your viewing pleasure, I inputed 462 KCAS at sea level:

True Airspeed ----- 462
Calibrated Airspeed ----- 462
Equivalent Airspeed ----- 462
Airspeed Compressibility Correction ----- 0
Mach Number -------- 0.6984
Equivalent Mach Number ------ 0.6984












[edit on 27 September 2009 by weedwhacker]

BLA,freakin BLA, freakin BLA
Did you just say above that a modified A3 aircraft shot a missile into the Pentagon on Sept 11 2001 or did I miss read something up there?
How fast? How many G's? what altitude? Was it coming from the north? Going quickly west?
Crap you got me all screwed up weedy.
No problem. I have had a lot of teachers in my life that were failures.

Originally posted by OpusMarkII
I've been doing some soul searching lately perhaps I too haven't been critical and skeptical enough over some of the claims made by the truth movement . However I still feel something isn't right about the official story . Here's a site I've been checking out regarding the commission .

www.911proof.com...

[edit on 27-9-2009 by OpusMarkII]

Very solid link, good stuff.
Have you seen, Who Killed John O'Neil ? A you tube video on 911.
Your doubts will be replaced with enlightenment. After reading all the crap on the thread, ---Do you now know what hit the Pentagon????

Originally posted by weedwhacker

You are (incorrectly) making a claim about KEASthat is completely unsupported by science.

Unsupported by science?

You think I'm making this up? I already told you the latest pilot presentation
has laid this out very nicely. There are registered pilots and aero
engineers which backed up their data.

Geez, I don't know where you get your science from, but I haven't
seen a 767 hit Mach 1 to this day!

The example that we have for structural limitations is Egypt Air.

Why is this not sufficient for our debate? It's a 767! It reach mach 0.99
and broke up in mid air. This means the airplane cannot handle the
forces on the body...not even at 22,000 feet.

So why should a 767 EXCEEDING mach 1 EAS, stay intact at SEA LEVEL
with more dense air?

Then you imply that UA 175 only exceeded VMo for less than 30 seconds!

How do you figure this? At what point in space did UA175 EXCEED 360 knots?

BACK IT UP

How long did it take UA175 to accelerate from 360 Knots to 510 Knots?

BACK IT UP

Furthermore, you seem comfortable with the fact that as the plane BEGINS
to cross over VMo, that the wings, ailerons, stabilizer, elevator, etc. would
be stable and in control?

Nothing would start to shake, oscillate, or prove difficult to control?

Are you "hearing" yourself?

You seem quite comfortable making all of these claims, yet you didn't
even know the NTSB had a flight study for UA175 complete with RADAR
analysis and speed?

Come on, "Weed" who are we kidding?

All three planes exceed VMo

All three pilots were rookies

No simulator could present the aerodynamic stresses, control factors, g's,
or anything of that nature.

You're trying to tell everyone here that three out of three targets were
nailed spot-on by three rookie "terrorist" pilots?

Something a fighter pilot , and a few 757/767 pilots could not achieve
in simulators after multiple tries until SLOWING DOWN TO LANDING SPEEDS?

Just to recap:

Rookie Terrorist Pilots - Zero flight time in a 757/767 hit 100% of their
targets (3 for 3) while exceeding VMo by 150 Knots- well over manufacturer
limit of maximum operating speed.

A fighter pilot and a few 767/757 pilots with a combined flight time of
100,000 hours + cannot hit targets in a simulator with multiple
tries at ONE g!!!1 ZERO %

Does anyone else buy this garbage?

You really need to watch that new pilot presentation...listen to what
experienced pilots have to say and aero engineers have backed up
scientifically.

[edit on 27-9-2009 by turbofan]

reply to post by turbofan



Why are you polluting this thread.

How long did it take UA175 to accelerate from 360 Knots to 510 Knots?

Everything I've written has been referenced to American Airlines 77, since THAT is the subject of this thread.

YOU keep bringing up United 175. (BTW...if you imagine an acceleration rate of just FIVE knots/sec...and that's conservative, could be faster...THEN the answer to your off-topic question is THIRTY seconds). Happy?

You seem quite comfortable making all of these claims, yet you didn't even know the NTSB had a flight study for UA175 complete with RADAR analysis and speed?

Of course I knew of the study on UA 175, to ESTIMATE speed based on radar and video evidence. But, we don't have the SSFDR, do we? THAT is why I tried to steer back to AA 77, since....see above!

So why should a 767 EXCEEDING mach 1 EAS, stay intact at SEA LEVEL with more dense air?

What part of the fact that KCAS, KTAS and KEAS are THE SAME AT SEA LEVEL have you failed to grasp?!?

I hate to sound rude, but it seems you have not read the material.

You think I'm making this up? I already told you the latest pilot presentation...

Well....sounds like they've just come up with a new wrinkle, then, to confuse non-pilots.

So why should a 767 EXCEEDING mach 1 EAS, stay intact at SEA LEVEL with more dense air?

Since that question appleis to ALL THREE airplanes in question, I will repeat:

The speed of sound at SEA LEVEL, standard day, is 667 knots. (actually, it's the TEMPERATURE of the air that determines Mach)


Please READ!:

In dry air at 20 °C (68 °F), the speed of sound is 343 meters per second (1,125 ft/s). This equates to 1,236 kilometers per hour (768 mph)...

NOW, convert 768 MPH to knots. OK?

This figure for air (or any given gas) increases with gas temperature (equations are given below), but is nearly independent of pressure or density for a given gas...

"nearly independent" of pressure or density...meaning that the differences are minimal.

Here, it was in chart format, but also from Wiki:

Altitude -- Temperature --m·s−1 -- km·h−1 -- mph -- knots

Sea level --15 °C (59 °F)-- 340 ----1225 ------761 -----661

11 000 m−20 000 m
(Cruising altitude of commercial jets,
and first supersonic flight)

---------−57 °C (−70 °F)-- 295 --- 1062 ---- 660 ------573


Basically, at SL....this graph shows 761 MPH/661 Kts (temp was different -- 15 C versus 20 C)

Between 11,000 m and 20,000 m?? They took ONE reprentative temperature (-57 C) and come up with 660 MPH/573 Kts.

Now, what is so difficult to understand?

.... as the plane BEGINS to cross over VMo, that the wings, ailerons, stabilizer, elevator, etc. would be stable and in control?

YES.

Nothing would start to shake, oscillate, or prove difficult to control?

Oscillate? NO. Difficult to control? NO. The 'shaking' you may refer to is commonly called "Mach Buffet". It sometimes occurs, depending on variables, before actually reaching Mach 1, because airflow over certain portions of the airframe begin to approach supersonic speeds, in very LOCAL areas. I have experienced it many times...yet I'm still here to type about it.

ALSO....this occurs at HIGH ALTITUDE, and depending on the airplane, and temperature and angle of attack, can be experienced close to MMO....or not at all, even for transient MMO exceedences. (Example: Turbulence, or 'mountain wave' events....where speed will accidentally near or exceed MMO. Proper monitoring keeps everything safe. BUT, not all encounters can be anticipated).

Something a fighter pilot , and a few 757/767 pilots could not achieve in simulators after multiple tries until SLOWING DOWN TO LANDING SPEEDS?

Hope he's retired, and not flying commercial passenger jets anymore!!!

Seriously...seriously...if someone WANTS to prove their point, and screw it up by appearinig "unable" to do something....well.....
______________________________________________________

Missed this one:

No simulator could present the aerodynamic stresses, control factors, g's, or anything of that nature.

WHERE do you think some magical g's are coming from, in basically level flight...oh, a slight pull from the shallow dive to nearly level...yeah, maybe a half g more....

The sim will recreate mach buffet...but NONE of those airplanes approached Mach at the low altitudes they were at. And control factors? The flight controls work the same way. SOME airplanes, depending on wing design and aileron placement, will exhibit a "control reversal" at excessively high airspeeds. What happens is, the ailerons when deflected, cause the WINGTIPS to react the opposite direction...if the wingtip is insufficiently stiff...and the result is a opposite control event. BUT, that's at the HIGH SPEEDS, and well not seen in the B757/767. (ESPECIALLY in the B767!!! The outboard ailerons "lock" into place, when flaps are retracted. THEY DO NOT OPERATE with flaps up. ONLY the inboard ailerons operate in the high-speed regime).

Any more questions?? These "pilots" you are so fond of --- they are certainly in a minority opinion.

Oh....and the red font makes my eyes hurt....






[edit on 28 September 2009 by weedwhacker]

Originally posted by weedwhacker
YOU keep bringing up United 175. (BTW...if you imagine an acceleration rate of just FIVE knots/sec...and that's conservative, could be faster...THEN the answer to your off-topic question is THIRTY seconds). Happy?

Fine. We'll talk "AA77" here, and I'll start a UA175 thread.

Where did "AA77" get the power to reach 462 knots (the last speed recorded
by the SSFDR)?

Max. operating speed for a Boeing 757-2xx is: 350.0 knots

This is the maximum safe operating speed for this aircraft at low
altitudes. How do you go over VMo by more than 25% and
expect the aircraft to stay together, and remain controllable?

What part of the fact that KCAS, KTAS and KEAS are THE SAME AT SEA LEVEL have you failed to grasp?!?

SO WHAT "PILOT"? What part of structural stress, air density and lack of
power do you not grasp? How does the airframe stay intact near sea level
if aircraft are proven to break apart at SLOWER EAS in THINNER AIR!

The speed of sound at SEA LEVEL, standard day, is 667 knots. (actually, it's the TEMPERATURE of the air that determines Mach)

NOW, convert 768 MPH to knots. OK?

Now convert to EAS. OK? What is the effective pressure acting on the
airframe? You can convert speed all day, but you can't forget about
the forces of air pressure acting on the jet!

I can't believe you are missing this point and not taking this into consideration
while claiming to be a pilot.

Between 11,000 m and 20,000 m?? They took ONE reprentative temperature (-57 C) and come up with 660 MPH/573 Kts.

Now, what is so difficult to understand?

NOTHING. That is a simple speed conversion.

My car will go 100 KM/H, or 55 MPH....HOWEVER the forces,
g's, etc. acting upon me and the vehicle while turning, or going over
hills (vertical component) CHANGES DRAMATICALLY.

Understand this simple concept?

.... as the plane BEGINS to cross over VMo, that the wings, ailerons, stabilizer, elevator, etc. would be stable and in control?

YES.

LMAO!

See above! Anybody here with half a brain can tell you the controls
and aircraft will handle differently at 150 knots slower.

You are NOT a pilot. You cannot be a pilot and continue to tell me that
I will move the yoke and position the aircraft the SAME way at any
speed going into a turn, or dropping altitude, or a combination of multiple
vector maneuvers.

pilot?

Oscillate? NO. Difficult to control? NO.

You are SOOOO easy to debate. Here are some videos of what happens
when aircraft exceed their design limits. Imagine piloting these crafts
going OVER manufacturer rated speeds with this happening (and you're a
rookie):

www.youtube.com...

THE SINGLE MOST DANGEROUS TEST

www.youtube.com...

www.youtube.com...

THere are HUNDREDS more examples, but you probably wont watch them,
or understand them.

From the papers of
OPERATION NORTHWOODS prepared by the Joint Chiefs of Staff 1962. Less than two years later the man that squashed the operation was murdered in the vice Presidents State of Texas.
His name John F. Kennedy

Wikipedia
#8
a. An aircraft at Eglin AFB would be painted and numbered as an exact duplicate for a civil registered aircraft belonging to a CIA proprietary organization in the Miami area. At a designated time the duplicate would be substituted for the actual civil aircraft and would be loaded with the selected passengers, all boarded under carefully prepared aliases. The actual registered aircraft would be converted to a drone.
b. Take off times of the drone aircraft and the actual aircraft will be scheduled to allow a rendezvous south of Florida. From the rendezvous point the passenger-carrying aircraft will descend to minimum altitude and go directly into an auxiliary field at Eglin AFB where arrangements will have been made to evacuate the passengers and return the aircraft to its original status. The drone aircraft meanwhile will continue to fly the filed flight plan. When over Cuba the drone will begin transmitting on the international distress frequency a "MAY DAY" message stating he is under attack by Cuban MIG aircraft. The transmission will be interrupted by destruction of the aircraft which will be triggered by radio signal. This will allow ICAO radio[16] stations in the Western Hemisphere to tell the US what has happened to the aircraft instead of the US trying to "sell" the incident.
It is possible to create an incident which will make it appear that Communist Cuban MIGs have destroyed a USAF aircraft over international waters in an unprovoked attack.

DEBUNK THIS

reply to post by turbofan


Boy, oh boy. You display your naivete' over and over, PLUS your lack of aviation knowledge and terms....

You are NOT a pilot. You cannot be a pilot and continue to tell me that I will move the yoke and position the aircraft the SAME way at any speed going into a turn, or dropping altitude, or a combination of multiple vector maneuvers.

Ummmm.....that IS how it works.

IF your car is moving at 5 MPH, and you turn the wheel a little, you turn a little. IF you are at 50 MPH, and ster the same amount, the result will be different.

(I hate using that comparison...words don't describe what I can SHOW you in flight....)

At slower airspeeds, more control deflection is required than at higher airspeeds. Go take a lesson and find out!!!

You just don't understand, and never will, until you hop down off your high horse and LEARN.

You show us a Twin Commanche, a video from 1966.

OF COURSE a general aviation airplane (light airplane for your parlance) is not as STRONG as a modern commercial transport category airliner!!!!

Don't you think manufacturers conduct destruction testing???

OH...then, brilliant!!! You find a video about the A380. Did you read the description?

They were testing the ability of the jet to hold together up to Mach 0.96!!!!

Because, that is considered a rare, but POSSIBLE situation that an aircrew may find themselves in. It's all part of the Certification Process, but I'm not certain you'd understand that.

The A-6 video....gee.

Not only have you not compared apples to apples, it's more like apples to nuclear submarines (I can't think of all the hyperbole analogies here....)

One last time. Just take a darn LOOK at the graphs, USE one of the online calculators!!!

Plug in any KCAS you wish, AT SEA LEVEL, then solve for KEAS. AND Mach number!!! Why won't you admit that the calculators show speeds not even close to Mach 1???

------
The dynamic forces are what they are....and a 100+ knots above VMO will NOT result, at those altitudes, in total airframe destruction. Do you think a 28% safety margin isn't designed in? Actually, in the stated G-load limits and such, a GREATER safety margin is built in. AT LEAST 50%!!!!!

Another reason for the stated limitations is AIRFRAME life expectancy. Having a comfortable 'limit' with large safety margins is what gives the jets their measure of safety!

You seem to know very little, but THINK you do. It is a rather typical layperson's mistake. Did you know, for instance, that the Indicated Airspeed VMO limit changes as you climb higher? On the airspeed indicator it is called the 'barber pole', because of its markings. The Air Data Computer looks at all the pitot static and outside temperature information, and re-calculates and moves the 'barber pole' within the insrument, because AT ALTITUDES abave about 20,000 feet MACH Limit is more of the determing factor in airspeed than KIAS (KCAS) TRUE Airspeed is higher than Indicated/Calibrated....and Equivalent airspeed and True airspeed are very close.

At the low, near sea level altitudes of the attacks, the increase above VMO will NOT result in immediate destruction of the airframe!!! UNLESS....and this is important....the airplane encounters very strong turbulence, while at those speeds. THEN some very severe structural damage is likely....OR, if a pilot operates the controls very roughly, as in large and abrupt control surface deflections....like VERY large. Especially in pitch.

However....again, you seem to think that VMO is some magical 'brick wall' beyond which the airplane will fall apart.

YOUR YT VIDEO of the A380 tears that whole idea to shreds!

Since you're unable/unwilling to believe me, nor understand me, try Boeing:


They intentiionally land IN A CRAB, in crosswinds that EXCEED what will eventually be the stated limits...as part of the Certification Process, again....(There is MUCH, MUCH more involved....) Watch the last one, especially. IF you know anything about flying, you may appreciate the amount of forces transmitted from the Landing Gear to the airframe....


Very old, but a goody. The 'infamous' Tex Johnson:


PAY attention....that roll [he said 'chandelle'...I have a different description for chandelle, that was what we call a "barrel roll" today] pay attention when he says "it's a 1 G roll..." because, it IS!!!


How fast do you think this Boeing 757 was going as it passed the camera? How did they survive?? And, the G-forces in that pull-up...wow! Why didn't the airplane fall apart??

(no....NOT 460 knots....analyze the video, if you can. I'll guess UNDER VMO, but only by maybe 30 knots...).


Any of this seem familiar?




[edit on 28 September 2009 by weedwhacker]

Originally posted by weedwhacker
OF COURSE a general aviation airplane (light airplane for your parlance) is not as STRONG as a modern commercial transport category airliner!!!!

This coming from a guy who would rather compare a 727 instead of a 767
when debating 9/11...but whatever, you are missing the point entirely
about STRUCTURAL LIMITS and what happens when you EXCEED limits.

OH...then, brilliant!!! You find a video about the A380. Did you read the description?

Oh and BRILLIANT!!! YOU FORGOT THAT THE FLUTTER TESTS ARE DONE
AT ALTITUDE IN THINNER AIR! NOT NEAR SEA LEVEL!!

Hey "pilot" at what altitude will the aircraft experience more aero drag moving
at the same relative speed:

#1. at sea level

#2. at 35,000 feet

Take your pick, you have a 50% chance of getting it right!

Because, that is considered a rare, but POSSIBLE situation that an aircrew may find themselves in. It's all part of the Certification Process, but I'm not certain you'd understand that.

PFFFFFFF LMAO! How many commercial airliners do you see moving 0.96
mach at 1000 feet ASL?

Hey "pilot" what is the altitude for this flutter certification? You get
one guess.


Bonus question: Why is the flutter test performed at this "altitude" instead
of near sea level at 0.96 mach?

Please, nobody else answer until "Weedwacker" responds to these basic
facts of physics and aerodynamics.

[edit on 28-9-2009 by turbofan]

Originally posted by weedwhacker
reply to post by turbofan

 

Why are you polluting this thread.


Oh....and the red font makes my eyes hurt....

LMAO!!!!!!!!!!!!
You are not a pilot. I thought it was obvious when you talked about the simulator but I thought I would just wait and see if I was wrong. Thank you! Thank you so much for these last couple pages. Not only are you not knowledgable enough to be qualified to pilot anything, I am not not so certain you qualify to be a passenger. You are hurting your own cause. When one of you spends so much time fighting the "truth movement" and then turn out to be a complete liar, how do you suppose that plays to all the people fence sitting?

reply to post by turbofan

Hey "pilot" at what altitude will the aircraft experience more aero drag moving at the same relative speed:

#1. at sea level

#2. at 35,000 feet

Take your pick, you have a 50% chance of getting it right!

Drag is relative, depends on angle of attack. You don't really understand aerodynamics. The same "relative" speed? (KCAS) You don't understand Mach numbers....and dynamic pressure....and temperature.

The true dynamic pressure "felt" by the airplane is only about 14.5% higher at sea level than FL350, for the same KCAS.

You won't look at the online calculator, will you? Afraid to??

Here: (I used the lower KCAS, because of Mach limits at FL350)

Scenario #1 Sea Level:

Airspeed (I chose 300 KCAS)

Equivalent Airpeed? 300 knots.

Mach #? 0.4535
Equivalent Mach #? 0.4535

True Dynamic Pressure? 304.7 lbs/sq. foot
----------------------------
----------------------------

Scenario #2 35,000 feet:

Airspeed (still 300 KCAS)

Equivalent Airspeed? 321 knots

Mach #? 0.8725
Equivalent Mach#? 0.4535 (Hmmmmm)

True Dynamic Pressure? 266.1 lbs/sq. foot

Of course, those numbers assume STANDARD temps, for Standard atmosphere.

PFFFFFFF LMAO! How many commercial airliners do you see moving 0.96 mach at 1000 feet ASL?

Once again, you miss the point of the A380 test. Not being intentionally obtuse, are you?

Hey "pilot" what is the altitude for this flutter certification? You get
one guess.

Ya know....I am not a test pilot. I trust others, in actual REAL flights, and in engineering via computers, to do that for me and make a safe airplane. But, on a modern passenger jet design (unlike the small airplanes) the problem of flutter is only going to be at high MACH NUMBERS.

FAA Flutter Certification can be performed by analysis only. Flight testing is dangerous and not required to meet the flutter criteria of paragraph 23.629 Amdt 23-459a)(2) (b).

Bonus question: Why is the flutter test performed at this "altitude" instead of near sea level at 0.96 mach?

Are you serious?????

Why is altitude in quotes?????

I hope you know the answer, 'cause I'm tired of giving you free ground school.....

Do you understand how dangerous it is, for a test pilot, to approach Mach 1 in an airplane not designed to exceed Mach??? YOU saw the video, right?

Did you not pay attention?

Also, as I have said at least five times....Mach number is dependent on TEMPERATURE! THIS MEANS, that at sea level the percentage of Mach for a given speed will vary from that for the same speed at altitude, BECAUSE the air is colder. IF the air, at FL350, was the same temp as sea level (well first, the airplane wouldn't have the performance capability ot climb up there, at that temp) but, IF it were there, the Mach would be the SAME. (about Mach 0.45, with a KCAS of 300.)

AND....anyway, there is no logical reason to expect the A380 to EVER approach Mach 1 near sea level!!!! Wanna know what the airspeed would have to be? Sea level, Standard temp....to get up to Mach 0.96, the KCAS would have to be 635K. That speed, at that altitude, is not acheivable. It MIGHT, if it were pointed almost straight down...but, also....the density of the atmosphere is such that parts would start to fall off....

As to the A380 tests....any Mach speed excursions are going to occur in the high altitude regime...your question, this entire "Test" is pointless, childish and completely indicative of your total lack of understanding.

I think you have a general misconception based on a false impression of the different static atmospheric pressures at sea level compared to FL350, and how that would aerodynmically affect the airframe. That is, you think that the are is SO dense, that it would tear the airplane apart instantly.

NOW....for AA 77, at 462 KCAS at sea level...the True dynamic pressure is
722.6 lbs/sq. foot. That is NOT good on the airframe, of course....and IF it were to happen in real life, with a safe landing afterwards, then the airframe would require a deep inspection...a full 'D'-check...or, might even be a "hull loss" write-off. Engineers and FAA would have to determine that.
--------------------------------
BTW....the reason it is more difficult to accelerate in more dense air is because of drag. Especially, parasitic drag, which increases with the square of speed increase. EVERY pilot knows that the amount of thrust available will eventually not be able to accelerate the airplane past a certain speed, at a certain altitude....UNLESS assisted by gravity, such as in a shallow dive.

A passenger jet, in a dive, will accelerate VERY rapidly, even with power at idle. You do NOT have to lower the nose to an uncomfortable pitch attitude. NOW...ad full thrust in this situation? Gonna go even faster.....

NOW....run along, take some lessons....because you get no more free ones from me.

reply to post by K J Gunderson


Two stars, for the ad hom of the year???

Sorry that YOU can't understand either...maybe I'm getting too technical???

OH....and you have a U2U.

NOW, run along and go play.....

Originally posted by K J Gunderson

Originally posted by weedwhacker
reply to post by turbofan

 

Why are you polluting this thread.


Oh....and the red font makes my eyes hurt....

LMAO!!!!!!!!!!!!
You are not a pilot. I thought it was obvious when you talked about the simulator but I thought I would just wait and see if I was wrong. Thank you! Thank you so much for these last couple pages. Not only are you not knowledgable enough to be qualified to pilot anything, I am not not so certain you qualify to be a passenger. You are hurting your own cause. When one of you spends so much time fighting the "truth movement" and then turn out to be a complete liar, how do you suppose that plays to all the people fence sitting?

and you guys just figured this out? LOL But his posts hurt my eyes so much, i had to put him on ignore... Now my eyes only hurt when i have to see his rambling when someone hits quote reply.

wacker is either in denial, can't comprehend basic physics, math and science or he's a shill. a PILOT?? HAHAHA!!! YEAH RIGHT. I and others have debated his faulty logic and fuzzy math/science ad naseum. Theres no point in doing so anymore unless you like attempting to reason with an ant.

A perfect example of wackers fuzzy logic... he links this video
www.youtube.com...

and uses it to support his argument.

2 basic obvious problems you'd think wacker would have thought about before he posted it:

1) its an A380
2) this test wasn't ASL and the speed they barely pulled off was mach 0.96

oh and Wacker, please pay particular attention to what is said at 6:32 and then tell me 77 and 175 could have done what they are claimed to have done.

where's captainobvious when you need him?

www.youtube.com...
thats what happens when an aircraft exceeds its structurally safe airspeed.

If flight 77 and 175 even existed (mountains of evidence of NRPT says they didn't), they could not have hit their targets or maintained their structural integrity at the speeds they allegedly acheived and maneuvers they were said to have made.

EOS.



[edit on 28-9-2009 by Orion7911]

Well "Weed" if it hasn't been obvious enough to you at this point,
you hit the grand slam of contradition right here:

Originally posted by weedwhacker

Do you understand how dangerous it is, for a test pilot, to approach Mach 1 in an airplane not designed to exceed Mach??? YOU saw the video, right?

For the last few pages you have been fighting, and fighting me on these
critical points, and NOW you agree?

What the heck? Dual personalities perhaps?

The above quoted paragraph written by you emphasizes the problem;
that problem being:

"Do you understand how dangerous it is, for a test pilot, to approach Mach 1 in an airplane not designed to exceed Mach??? "

By the same token, and using pressure at lower altitude, EAS, etc., we
can apply this very same quote!

The aircraft was designed to fly at 360 knots. This is the craft's structural
limit. Velocity MAXIMUM OPERATING.

The plane did not go over by 10 knots. It did not go over by 30 knots.

It did not go over by 50 knots. It went over by ONE HUNDRED AND FIFTY KNOTS! 1 - 5- 0 knots!

What was that you said about drag increase with the speed?

Wanna know what the airspeed would have to be? Sea level, Standard temp....to get up to Mach 0.96, the KCAS would have to be 635K.

DING, DING, DING!!! Has the light bulb gone off yet? REVERSE THAT
ANALOGY SO YOU CAN GET ON THE SAME PAGE!

What is EAS at 35,000 feet.

It's OVER mach 1.

You admitted to this!

Can a Boeing 757/767 fly at MACH 1 (IE: Break the sound barrier) at
35,000 feet.

THe answer is NO!

You ADMIT IT HERE AGAIN:

That speed, at that altitude, is not acheivable.

By the SAME token, the 757/767 CANNOT reach speeds 150 Knots
over VMo at Sea level (Pssst...has that light bulb turned on yet?)

YOu imply the difficulty in your next quote: Were AA77, or UA175
pointed straight down in order to reach speeds beyond max operating?

NO!

YOu even said so. You even stressed the word MIGHT!

It MIGHT, if it were pointed almost straight down...but, also....the density of the atmosphere is such that parts would start to fall off....

Wow

Parts would start to fall off?!!! NO FREAKIN' KIDDING!

We have proof. Egypt Air. You said parts will fall off.

So why the heck are you fighting me on these points "weed"?

What are you trying to argue if you agree that parts would fall off?

You are confusing me and everyone else here I'm sure.

To recap:

- a 767/757 cannot reach speeds 150 knots over maximum operating speed

- a 767/757 cannot break the sound barrier at 35,000 feet

- air is more dense near sea level and therefore increases drag on
the air frame

- aircraft exceeding their max operating limits will begin to break apart.

Originally posted by weedwhacker
reply to post by K J Gunderson

 

Two stars, for the ad hom of the year???

Sorry that YOU can't understand either...maybe I'm getting too technical???

OH....and you have a U2U.

NOW, run along and go play.....

What a sweet letter. You are so kind to put in the effort. There is one problem with it though. When I say things like I am a mechanic, accountant, superman, whatever...there is really little you can do to prove it, correct? Sending me a personal little letter proclaiming that you are this and that and you did this and that, is worth just about what here on the internet? You almost sound convincing too up until you say "ask anyone who knows me here." Are you 15? I hope so because otherwise this is going to hurt:

This is not a here. These "people" do not know you from a hole in the wall. Getting another internet stranger to say yes, this internet stranger is who he says he is would be worth just about what to you if it were the other way around. I cannot imagine that a true pilot and man of some maturity would say such a jouvenile obvious thing. Hey, you be whoever you want to be. Your failures in logic speak for themselves. I just thought you might want to stop stealing all the credibility from your point of view.

reply to post by Orion7911


Dude....with no due respect...

TURBOFAN linked the A380 video!!!!!!!!!! Do you know why?

A perfect example of wackers fuzzy logic... he links this video
www.youtube.com...

Because HE thinks that it "proves" that aomehow American 77 was doing Mach .96 at sea level...or something, his "logic" is nonexistent.

Problem with you laypeople is you CAN'T understand the technical aspects of it. This is ridiculous, because it's like trying to describe a spherical Earth to people who are CONVINCED it's flat. "It has to be....look at them stars move over head!!! And the SUN....!!! IF the Earth was turnin', we'd all fly right off!!!"

That's a bit of what I'm dealing with....and it's pointless, since BECAUSE none of you are pilots, you will never understand, from a blog on ATS.

SO......

New tactic. I've TRIED to deny ignorance. I'm frustrated because I have students who won't accept, won't even BOTHER to look at the many sources I provided, and the data.

SO....my new tactic??

I want to PROMOTE ignorance.

NOW...which one of the geniuses out there who have it all figured out can finally answer the OP's question?

WHAT HIT THE PENTAGON ON 9/11/01?

Come on....let's see it....

Doesn't count, though, unless you find a way to explain:
--------------
The debris at the crash site.

The DNA.

The eyewitnesses. ALL of them, even the few who've changed their stories.

The Flight Recorder data.

The missing airplane owned (or leased) by American Airlines.

The hundreds of First Responders at the Pentagon...civilians...who know what they saw.

The continuing hundreds (or thousands) of more individuals who participated in sifting through the debris to find and identify everything they could, not only for forensics, but to find every remaining piece of "whatever" hit.

The LACK of any parts in the debris OTHER than from a Boeing.

The missing passengers and crew.

The personal effects of the passengers and crew, reccovered at the site.

NOW, that shouldn't be so hard???

Let's back up.....to BEFORE the "whatever" hit.

ALL of the American Airlines employees who interacted with flight 77 at Dulles, that morning. Ground workers, any Reservations agents who may have been called, the AA Flight Operations and Dispatch people in Dallas...etc...???

Why mention them? Because, if you found just ONE of them to cry "It Didn't Happen!" then you'd have a very good start to make your case.

NOW....ALL the ATC personnel who interacted with Flight 77...with the flight crew, on the radio, prior to the hijacking.

The recordings from the FAA computers, and radar, that showed the airplane had an active flight plan, and was in flight.

AND the ATC personnel who SAW it, from the DCA Tower. O'Brien, the pilot in the C-130 just out of Andrews who saw it.

YOU HAVE to find an explanation for all of them.

I've probably missed something....
--------------------------------------

Now, what are the many prevailing "theories"?

AND where is any supporting evidence for these?

I have a few in mind, but I'd rather promote ignorance, and see what the "true believers" think.


PS...one more thing. Please also explain to us how the "perps" could be SO FREAKIN' STUPID to "fake" the SSFDR ('cause I expect that's gonna be one of the "theories") and screw it up so badly that a few wannabe pilots can "see right through the lie"?????

Originally posted by weedwhacker
TURBOFAN linked the A380 video!!!!!!!!!! Do you know why?

YOU DON"T EVEN KNOW WHY!

Because HE thinks that it "proves" that aomehow American 77 was doing Mach .96 at sea level...or something, his "logic" is nonexistent.

FOR THE MILLIONTH FREAKIN TIME:

The video shows that aircraft exceeding their STRUCTURAL LIMITS (IE: VMo / MMo ) begin to break apart and become "out of control".


YOu make me laugh and cry...because it's a shame you have to play
pretend pilot and screw up massively.

It's clear in the quoted examples above your logic and comprehension
of these basic aero analogies escapes you.

For crying out loud, there are non-pilots keeping up with the discussion
and poking fun at you!

"weed" why don' t you post your name so we can look you up on FAA.gov
like the pilots and aero engineers listed at Pilots for Truth?

It takes just something simple like that to prove your capabilities.

Come on, you know my full name. What are you afraid of? You are on
side with the government! THey'll protect you right?