The Ground Effect: Why a 757 Going 500 mph Couldn't Have Hit the Pentagon

[spooked911]

traveling only a few feet off the ground.

The basic idea is a Boeing 757 is simply not designed to fly so fast so close to the ground and simply can't do it. This is because of the huge lift created under this huge plane going so fast. Not to mention there is an effect called "downwash", where the plane creates a huge suction under it as it flies. This would have picked up everything that was under a 757 and thrown it in all directions-- for instance cable spools and electrical generators.

This basically demolishes the official Pentagon story.

Listen to the 6-6-2005 interview with Nila Sagdevan here for details:
http://911verses.com/underground/

Interestingly, a military plane or a global hawk COULD travel 500 mph that low to the ground.

[LARED]

1. Downwash

http://www.grc.nasa.gov/WWW/K-12/airplane/downwash.html

[spooked911]

3. Actually, downwash may not be the right term for what Sagadevan

was describing.

I would recommend listening to the first part fo the show.

[hack89]

2. Wrong..

from Wikipedia: "Most pilots, especially of small aircraft, will experience ground effects on landing" and "As the aircraft descends towards the runway, it will not be affected by ground effect, but as the aircraft flares and descends the last few feet."

Flt 77 was a big aircraft and it did not slow to flare - it was at full speed with flaps up. Ground effect is more than close proximity to the ground - it involves slow speeds mere feet above the runway. Even if it had any effect, how high would it risen before it hit the building? Why couldn't the pilot simply overcome any lift by simply pushing the yoke forward?

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

[spooked911]

4. Did you even read the rest of your link?

from your Wikipedia source: As the aircraft descends towards the runway, it will not be affected by ground effect, but as the aircraft flares and descends the last few feet, ground effect will cause a pronounced increase in lift. This can cause the aircraft to rise suddenly and significantly — an effect known as a "balloon". Left uncorrected, a balloon can lead to a dangerous situation where the aircraft is rising yet decelerating, a condition which can rapidly lead to a stall, especially when it is considered that landing speeds are generally only a very small margin above the stall speed. A stall even from a few tens of feet above the ground can cause a major, possibly fatal, crash. A balloon may be corrected given sufficient runway remaining, but for novice pilots a better option is to go around. A good landing approach allows for ground effect such that the aircraft flares and is held off in ground effect until it gently descends onto the runway.


The point being that it is crucial that the aircraft go the right speed when descending.

Perhaps going faster will overcome this problem, as you say. This Sagadevan fellow, who claims to be an aeronautical engineer, says the ground effect will increase with plane speed and will prevent the plane from going close to the ground. That is his claim, although I can't vouch for it myself. Perhaps he is wrong.

[hack89]

7. I certainly understood it better than you...

Lets summarize shall we:

Ground effect comes into play when:
1. Plane is going slow (near stalling speed) as it prepares to land.
2. When plane then flares feet above the runway.
3. When the difference between landing and stalling speed is small.

Now lets look at flt 77:
1. Plane going very fast as it has no intention of landing.
2. Stalling speed for 757 is below 200mph.
3. Plane does not flare for landing.
4. Plane travel hundreds of miles per hour over stalling speed.


If ground effect was a factor, it would have been right next to the impact point due to the planes descent path - remember that ground effect exists only feet above the ground. There are two issues as I see:

1. How high a balloon? Are you saying the plane would have gone straight up and hopped over the Pentagon?

2. With the plane traveling at 300 mph above stalling speed, are you saying that the plane would lost 300 mph of forward speed almost instantly, stall and hit the ground short of the Pentagon?

Perhaps he is wrong.

[spooked911]

9. See my post #8

It is not clear to me that ground effect only comes into play when the plane is going slow. The reference I put in post #8 contradicts this.

Intuitively, it seems to me there would be more ballooning at higher speeds next to the ground.

The question is whether a 757 going 500 mph would balloon significantly as it reaches the ground effect elevation, which would be about 30-60 feet for a plane with a 125 foot wingspan.

[hack89]

10. But again..

If the pilot sensed the aircraft rising all he would need to do is push forward on the stick to point the nose of the aircraft at the target. There would be no danger of stalling due to its high speed. Remember, ground effect can be anticipated and corrected for.

[spooked911]

11. But yet again...

The plane could NOT descend into the "Ground Effect" region, without the aircraft being in a pronounced dive - which is an impossibility - relative to the "official" story.  Such a dive would have left a distinctive seismic impression*; and a crater.

http://home.comcast.net/%7Eskydrifter/exp.htm

*Unlike the two WTC crashes and the flight 93 crash, the Pentagon crash left no seismic signal.

[Sgt. Baker]

32. because

comcast.net's Doyle knows better than a pilot what the effects of ground effect are. :eyes:

At least give a link that has some kind of credibility. Just because someone who has a conspiracy site says something it doesn't mean it's true.

[Kevin Fenton]

5. Slowed down

This doesn't seem especially promising. If the plane can't fly so fast close to the ground, why not just slow down?

[spooked911]

6. The point was that the plane officially was going 500 mph.

So either the official story is wrong about the plane speed or Sagadevan is wrong.

Admittedly, I can't verify this Sagadevan's claims about the ground effect.

[spooked911]

8. OK, finally found a confirmation for this ground effect claim

http://www.avweb.com/news/airman/185905-1.html

When an aircraft enters ground effect during the landing flare, the aircraft may tend to float because the lift-induced drag is reduced quite dramatically as the aircraft descends below one wingspan distance from the ground. Any excess speed at all -- you know, the 10 knots for Ma and the kids -- will cause this float to become excessive.

A one wing-span length for a 757 is about sixty feet. Yet the plane that hit the Pentagon was supposedly just about six feet off the ground-- well BELOW the ground effect force.

I think even a highly experienced pilot would have trouble getting the nose down of a Boeing 757 going 500 mph just a few feet off the ground.

Yet we are expected to believe that the flight 77 Boeing 757 hit the Pentagon essentially level and just a few feet off the ground.

[hack89]

12. Read your post...

"When an aircraft enters ground effect during the landing flare..."

Flt 77 was not in a landing flare! A landing flare is a nose up, flaps down, slow speed configuration for landing. Flt 77 was nose down, flaps up and at a high speed. By your definition, Flt 77 could not have been effected by ground effect.

[Sgt. Baker]

13. vortices

The air flowing off of the wings of an aircraft form vortices. In straight flight these vortices are small. The smaller the vortices are the less drag will be produced. Low drag makes the airfoil more efficient and ultimately saves money on fuel. Basically, the modern wing of an airplane is pretty damn efficient and produces little drag during flight.

When landing, the aircraft comes in nose up increasing the angle of attack of the wing which creates more drag and much larger vortices. These vortices are what cause ground effect in fixed wing aircraft. As the plane gets closer to the ground those large vortices become compressed between the wing and the ground. This increases pressure under the wing and will make the plane rise slightly.

Since we know the plane was not coming in for a proper landing ground effect being a factor is incredibly unlikely. The plane actually came in at a downward angle at about 500kts. At that angle and speed the vortices would be very small and wouldn't contact the ground at all.

[Ezlivin]

15. The angle of entry must be nearly parallel to the ground

Or else you cannot explain the path of the plane through the Pentagon.

You said: "Since we know the plane was not coming in for a proper landing ground effect being a factor is incredibly unlikely. The plane actually came in at a downward angle at about 500kts. At that angle and speed the vortices would be very small and wouldn't contact the ground at all."

In order to "avoid" ground effect, the aircraft must come in an an extreme angle; basically nose down. At this extreme angle, most of the aircraft's energy will be directed downward. This, in turn, would mean that the resulting damage would not be similar to what was found.

[hack89]

17. Aircraft attitude is the key to ground effect..

An aircraft is affected by ground effect when it is in a landing flare. A landing flare is a nose up, flaps down, slow speed configuration for landing. Flt 77 was slightly nose down, flaps up and at a high speed. At high speed an aircraft will shed most vortices behind them, even at low altitude. It does not require an extreme downward angle to avoid the ground effect - speed was the critical factor. Remember- the danger of ground effect is that the aircraft stalls. Flt 77 was traveling more than 300 mph above its stalling speed - it was not going to stall.

[spooked911]

23. But the link I found said the flaring or ballooning was more pronounced at

higher speeds. You disagree?

Wouldn't higher speeds produce more pressure beneath the plane?

I don't think the ONLY danger of the ground effect is that the airplane stalls-- the stalling is more important if you are coming in slow to avoid the ballooning or flare effect.

[Sgt. Baker]

21. listen to Hack89

He knows what he's talking about.

[Ezlivin]

25. Hack 89 didn't address my answer

And neither did you.

Let's talk about the angle of attack.

Was it steep as you said or was it level as the government claims?

[Sgt. Baker]

29. no difference

I never said it was steep, you assumed that. I said it was coming in at a downward angle. Even if coming straight in there would not be much if any ground effect. The plane was traveling at about 500knots. The vortices coming off the wings would be incredibly small and stretched out having no contact with the ground. As hack89 said, ground effect only happens to fixed wing aircraft as they flare for landing. I explained the difference between straight flight and flared flight on the vortices in a previous post and only the flared flight will cause ground effect. If you can prove the laws of physics wrong you win.

[Ezlivin]

30. It's NOT ABOUT THE GROUND EFFECT

Please read the next sentence carefully:

This is not about GROUND EFFECT.

It is about the angle that the airliner struck the Pentagon.

You said: "Since we know the plane was not coming in for a proper landing ground effect being a factor is incredibly unlikely. The plane actually came in at a downward angle at about 500kts. At that angle and speed the vortices would be very small and wouldn't contact the ground at all."

In order to account for the damage, the aircraft must fly parallel to the ground for some distance. If the nose of the aircraft was pointed at the ground, the energy and damage would have been directed downwards. The resulting damage would have resembled what occurred in Pennslyvania: A hole in the ground.

Please tell me what angle the aircraft came in at: 0°, 10°, 20°,...

The governent says it was 0° and that accounts for the aircraft proceeding along its path of travel.

[Sgt. Baker]

31. fine with me

0 is fine with me.

Where we going with this?

[Ezlivin]

34. It's a discussion of the entry angle, that's all

You said that the aircraft's angle with the ground was 0°. This means that the aircraft was flying parallel to the ground.

If it was flying parallel to the ground it follows that it must have been doing so for a period of time.

It was flying like an aircraft attempting to land, only to find the Pentagon right at touchdown point.

Does the last sentence accurately reflect what you believe to be the attitude of Flight 77 as it approached the Pentagon?

If not, how would you describe it?

Thanks.

[Sgt. Baker]

35. not very long

It couldn't have been flying parallel for very long at all considering the terrain around the pentagon. At the speed it was going I'd say 1-2 seconds.

[Ezlivin]

37. Okay, parallel for "1-2 seconds"

The slowest approach speed for a 757 is 152 mph.

152 mph = 13,376 feet per minute = 222 feet per second

Nearly a football field in length. And the only way a 757 can fly at 152 mph is with full flaps. Most definitely in ground effect.

But we need more speed to create the tremendous amount of energy to create the damage.

300 mph = 26,400 feet per minute = 440 feet per second

If Flight 77 flew parallel to the ground for 1 second at 300 mph it would have covered 440 feet, nearly 1½ football fields in length.

Partial or no flap approach. But in ground effect nonetheless, since it is not dependent upon speed, but distance from the surface.

[ROH]

38. Even faster ... 530 mph according to the CR

According to the CR:

"At 9:37:46, American Airlines Flight 77 crashed into the Pentagon, traveling at approximately 530 miles per hour."

http://www.9-11commission.gov/report/911Report_Ch1.htm

[hack89]

59. How is a missile ...

going to fly parallel to the ground to created the damage seen?

[Ezlivin]

36. Ground effect has nothing to do with "flaring" for landing

Ground effect is a physical phenomenon that is created when the aircraft is approaching the ground at different angles, regardless of speed.

You can use ground effect to accelerate an airplane after lift-off on a short- or soft-field takeoff -- or you can float halfway down the runway by being too fast on final.  ( http://www.avweb.com/news/airman/185905-1.html )

I've done this. I've come in too fast (hot) and could not touchdown where I intended. Typically a pilot will turn from base to final (or a long final for large aircraft) and set up an approach. The angle of approach is determined so that the aircraft can touch down at a specific point on the runway. This is very important; too long on final and you can overshoot the runway after touchdown.

So, in effect, the pilot wants to "hit" a specific spot on the runway.

If you come in too fast on your approach, ground effect will cause you to "float" down the runway many feet further than you intended, thus making you miss your target landing point.

In your head, rewind the Pentagon crash from point of impact back into the sky. What sort of approach do you imagine?

To hit the spot that it did requires that the aircraft:

1. Experienced ground effect, then "touched down" at the impact point, or;


2. Came in at a sharp angle, avoiding ground effect and striking the Pentagon.

The choice is either a traditional landing-type approach, or a dive-bomb approach. Only the dive-bomb approach can avoid ground-effect because of the acute angle of attack.

[Sgt. Baker]

43. your experience

with ground effect is only during landing when the nose is up and the aircraft is flared for landing.

Have you ever just flown steady and level over the runway?

Are you guessing that it has to be dive bomb or nothing to avoid ground effect?

The reason you float down the runway when coming in to hot for a landing is vecause you are flared and the vortices being created are huge. With the increased speed those vortices move more air and create more pressure under the wing. But they still only contact the ground if the plane is flared.

[Ezlivin]

44. Again, you are wrong

Ground effect has nothing to do with "flaring."

Please provide a reference that counters the one I've provide below or refrain from spouting nonsense.

When the aircraft is close to the surface -- in ground effect, -- coming into contact with the surface modifies the almost cylindrical vortex-induced circulation around the wing. This flattens the cylindrical circulation pattern and reduces the downwash angle of the air behind the wing. This flattening of the cylindrical circulation spreads the pattern outwards below the wing and increases the effective span of the wing. The aerodynamic aspect ratio of the wing is also increased. (The aerodynamic aspect ratio of the wing is measured between the cores of the vortices, which occur at about 80% of the geometric wingspan outside of ground effect. This aerodynamic aspect ratio has a strong inverse effect on lift-induced drag.)
When the aircraft flies close enough to the ground that the sag of the vortices trailing the wingtips is restricted by coming in contact with the ground, the backward-tilting angle of the total lift vector is reduced, thereby reducing its horizontal component and reducing induced drag.
The combination of the reduction in the downwash angle of the air behind the wing and the increases of both effective wingspan and aerodynamic aspect ratio of the wing occur when the wing is close to the surface. These increases in aerodynamic efficiency of the wing are what we call ground effect. ( http://www.avweb.com/news/airman/185905-1.html )

[spooked911]

45. Ezlivin-- since this is not my area of expertise, could I ask you simply

are you confirming the basic idea that it would be difficult (or even impossible) for a large jet moving at 500 mph to fly horizontally six feet off the ground to impact the Pentagon?

I think this is what you are saying, but I'm not sure.

[Sgt. Baker]

46. no

what the article says is that you can fly level in ground effect without much trouble at all. When you run into trouble is when you are flared for landing and come in to fast which causes float. The article actually states that you can fly faster in ground effect during level flight than you can higher up. You can also get into trouble during the transition to or from the ground effect zone. Going in level can actually cause the nose to dip if you are not prepared for the transition according to the article. Coming out can cause the nose to rise initiating a stall situation if you are not prepared.

I was partially wrong with some specifics about ground effect but this article still doesn't prove ground effect had any influence on the plane.

[spooked911]

47. But the other point is that ground effect causes this ballooning effect

where it is difficult to completely descend and land if you are going too fast.


The ground effect is equal to one wing length, or sixty feet in the case of a Boeing 757.

So the question is, can a Boeing going over 500 mph travel only six feet off the ground in a horizontal path?

[Sgt. Baker]

48. yes

the balloning effect is the same thing as the float and only comes into play when the plane is flared for landing.

[Bolo Boffin]

50. Article on ground effect

http://www.avweb.com/news/airman/185905-1.html

It reinforces the fact that only the landing flare causes the ballooning effect - a level plane's ability to accelerate is actually
enhanced because of ground effect.

It also explains why the pilot could hold the plane level to the ground while flying so close - the plane was sliding along a cushion of wing drag. It occurs to me that this would also require no particular skill as a pilot, other than having the nerve to attempt it.

It also occurs to me that Hani Hanjour's apparent problem with flying might have been misinterpreted by his teachers. Perhaps he was experimenting with the ground effect, and his teachers interpreted it as a problem with landing and taking off. Think about it - if a student is playing around with ground effect, but not telling his instructors that, wouldn't it be natural to assume that the man can't land a plane?

[LARED]

54. Excellent point

about the evidence that Hani Hanjour may have been testing the ground effect. Of course that would be interpreted as poor piloting. More evidence of just how sophisticated the hijackers could be.

Dang, that was fun turning speculation into evidence.

[Bolo Boffin]

58. : D

Just when I was despairing once again of these discussions, something worthwhile popped up.

[philb]

56. implausable. no indications in statements of this

and not even clear he would have known about it

[Bolo Boffin]

57. why implausible - no indications because I just figured it out

not even clear he would have known about ground effect? I believe that's something all piloting students are told about.

In fact, the article says that planes right after liftoff use the ground effect to accelerate before rising further in the sky. So yes, he would have known about it.

I know, it's really disappointing to have an card taken out of your hand and used against you...

[spooked911]

61. Look, Hani Hanjour was just a bad pilot, period.

They did not think he was bad because he played with the ground effect. Jeesh. That is as much of a leap of imagination as anything you accuse us of.

"Mr. Hanjour, who investigators contend piloted the airliner that crashed into the Pentagon, was reported to the aviation agency in February 2001 after instructors at his flight school in Phoenix had found his piloting skills so shoddy and his grasp of English so inadequate that they questioned whether his pilot's license was genuine.

Records show a Hani Hanjour obtained a license in 1999 in Scottsdale, Ariz. Previous and sometimes contradictory reports said he failed in 1996 and 1997 to obtain a license at other schools.

"The staff thought he was a very nice guy, but they didn't think his English was up to level," said Marilyn Ladner, a vice president at the Pan Am International Flight Academy, which operated the center in Phoenix. Ms. Ladner said that the F.A.A. examined Mr. Hanjour's credentials and found them legitimate and that an inspector, by coincidence, attended a class with Mr. Hanjour. The inspector also offered to find an interpreter to help Mr. Hanjour, she said.

"He ended up observing Hani in class," Ms. Ladner added, "though that was not his original reason for being there."

Company officials briefed members of Congress about the case, including Representative James L. Oberstar, Democrat of Minnesota, who made public some of its general details in December.

The aviation agency did not return a call for comment.

Pan Am International, one of the largest pilot schools in the nation, also operated the flight school in Eagan, Minn., near Minneapolis, where the instructors' suspicions led to the arrest of Zacarias Moussaoui, the man whom the authorities have said was intended to be the 20th hijacker.

Ms. Ladner said the Phoenix staff never suspected that Mr. Hanjour was a hijacker but feared that his skills were so weak that he could pose a safety hazard if he flew a commercial airliner.

"There was no suspicion as far as evildoing," Ms. Ladner said. "It was more of a very typical instructional concern that 'you really shouldn't be in the air.'"

A former employee of the school said that the staff initially made good-faith efforts to help Mr. Hanjour and that he received individual instruction for a few days. But he was a poor student. On one written problem that usually takes 20 minutes to complete, Mr. Hanjour took three hours, the former employee said, and he answered incorrectly.

Ultimately, administrators at the school told Mr. Hanjour that he would not qualify for the advanced certificate. But the ex-employee said Mr. Hanjour continued to pay to train on a simulator for Boeing 737 jets. "He didn't care about the fact that he couldn't get through the course," the ex-employee said.

Staff members characterized Mr. Hanjour as polite, meek and very quiet. But most of all, the former employee said, they considered him a very bad pilot.

"I'm still to this day amazed that he could have flown into the Pentagon," the former employee said. "He could not fly at all." (nytimes)"

http://www.humanunderground.com/11september/pent-hijackers.html


The real question is not "did he pilot flight 77 into the Pentagon", because he clearly didn't-- but rather HOW THE FUCK DID HE GET A PILOT'S LICENSE IN THE FIRST PLACE????

Anyone care to answer that?

[Ezlivin]

49. Ground effects

A large jet moving at 500 mph could fly above the ground; it would find it hard to "nose down" to land—without slowing.

In fact, ground effects are so important that new aircraft may utilize them.

Stephan Hooker's engineering firm, Aerocon, has been commissioned by the Pentagons' Defence Advanced Research Projects Agency (DARPA) to explore the potential of wing-in ground effect flight.
<snip>
Hooker's current concepts would be capable of about 400 knots, just slightly slower than a jetliner.
( http://142.26.194.131/aerodynamics1/drag/WIG.html )

Note that this "wingcraft" is not capable of flying. It can only operate in ground effect. Even at maximum thrust, it would be incapable of gaining more than a few feet of altitude. It rides on the cushion of air beneath it that is created by ground effect. To land, the wingcraft needs to slow down, thus dropping out of ground effect (ground effect is generated by airflow over the wings; slow the airflow and you decrease ground effect).

[Sgt. Baker]

51. pretty cool

That thing is pretty cool. It's not an airplane though. That thing was specifically designed to use ground effect so it will act differently than an airplane.

[spooked911]

53. True or false-- the ground effect height is about the length of one wing

which in the case of a Boeing 757, is 60 feet, right?

Granted a plane can fly at the ground effect height and can fly more efficiently at that ground effect height.

But if you are going over 500 mph, isn't there also some force that will keep you from getting too close to the ground-- for instance from landing? If you are a Boeing 757 and going over 500 mph, how close to the ground can you get if you are going horizontally and not diving?

[AZCat]

62. It's a bit more complicated than that

There are two types of ground effects: span dominated ground effect and chord dominated ground effect. The first kicks in earlier (about one wingspan above ground) than the second (approximately one chord length above ground). Span dominated reduces drag on the wings while chord dominated increases lift, but neither prevent the aircraft from getting close to the ground, especially when the aircraft is as massive as a B-757 - the forces generated (or reduced) by the cumulative ground effect is not strong enough to do much to a plane that big.

There are also several other factors that come into play: air density, wing geometry, the position of the control surfaces. It's not as easy as a "rule of thumb" might suggest, unfortunately.

[philb]

14. Doesn't anyone have access to an expert pilot or aeronautical engineer?

If not, someone should call up someone at a Univ. or flying school or
company with expertise in such.
Most of this discussion is speculation of people without enough knowledge and background to resolve the issue.

[Ezlivin]

16. I'm a pilot

But I'm only rated on PA-28s, not the big, commercial airliners.

However, the professional pilots I've talked to do not believe the official story. Taking over the controls of a complex aircraft at altitude is not as easy as it has been portrayed.

Pilots are as reticent to speak out about 911 as they are about the numerous UFOs they see.

[ROH]

18. Can you share any more information, please, ...

on what the professional pilots have said to you regarding the "official story".

(No need to divulge any names or personal information.)

[Ezlivin]

19. More Info

One of the most common responses is the highly improbable nature of a successful cockpit broaching without the pilot/copilot being able to send an alert. An aircraft's crew has more than one place on the aircraft to signal distress (particularly a hijacking).

Another problem is with the commandeering of the aircraft while at altitude and with the Flight Management System programmed. As any pilot will tell you, navigating by visual means is not as easy as it first appears. The problem is multiplied by altitude and speed. Navigating from one area of a country to another by visual means at flight levels is not easy. The hijackers had to know how to disable the FMS, take the controls and navigate via VFR (visual flight rules) to their target. The flight paths they took are very odd and make their task much harder.

The last and most difficult thing for pilots (the ones I've spoken to) to understand is the control of the aircraft at low levels and high speeds. Aircraft do not handle or perform the same at sea level as they do at flight levels (which start at 18k ft MSL in the US). Whoever (or whatever) piloted the aircraft into the WTCs and the Pentagon displayed stellar piloting skills. This appears difficult to reconcile with the reported skill levels of the hijackers.

[ROH]

20. Thank you

"One of the most common responses is the highly improbable nature of a successful cockpit broaching without the pilot/copilot being able to send an alert. An aircraft's crew has more than one place on the aircraft to signal distress (particularly a hijacking)."

That seems very important to me. As far as I know none of the four flights (Flights 11, 175, 77 and 93) issued any distress signal.

"Another problem is with the commandeering of the aircraft while at altitude and with the Flight Management System programmed. As any pilot will tell you, navigating by visual means is not as easy as it first appears. The problem is multiplied by altitude and speed. Navigating from one area of a country to another by visual means at flight levels is not easy. The hijackers had to know how to disable the FMS, take the controls and navigate via VFR (visual flight rules) to their target. The flight paths they took are very odd and make their task much harder."

OK. Were any comments made about the turning off / changing of the transponder codes that occurred on all four 9/11 flights?

"The last and most difficult thing for pilots (the ones I've spoken to) to understand is the control of the aircraft at low levels and high speeds. Aircraft do not handle or perform the same at sea level as they do at flight levels (which start at 18k ft MSL in the US). Whoever (or whatever) piloted the aircraft into the WTCs and the Pentagon displayed stellar piloting skills. This appears difficult to reconcile with the reported skill levels of the hijackers."

The Flight 77 approach (high speed, low altitude, depth of turn, etc.) has been discussed in this forum many times. The piloting of the flights into the WTC towers seems easier to accept to a layman; do the professional pilots also tend to see the Flight 77 piloting as being the hardest to explain of any of the 9/11 flights?

[Ezlivin]

24. FYI

I can tell you this about the three (3) pilots I've spoken to.

One just switched from right seat to left seat on the 757 (copilot to pilot). Another is a retired navigator, the other a retired C-5A pilot instructor. Two of them are former military pilots.

I've not asked the particular question you've posed ("...do the professional pilots also tend to see the Flight 77 piloting as being the hardest to explain of any of the 9/11 flights?"), but I will the next time I see one of them.

My feeling is that the closing speed of the jets with the WTCs was such that they really had to have it "lined up" right the first time, or else they would have missed and had to come around for another shot.

Every time I look into the actions of the pilots on 9/11, I'm amazed at how professional they were every single step of the way. They do not sound like the bumbling fools they've been made out to be.

[ROH]

26. Thanks. Would you also ask about the transponders please?

"I can tell you this about the three (3) pilots I've spoken to.

One just switched from right seat to left seat on the 757 (copilot to pilot). Another is a retired navigator, the other a retired C-5A pilot instructor. Two of them are former military pilots."

Experienced pilots.


"My feeling is that the closing speed of the jets with the WTCs was such that they really had to have it "lined up" right the first time, or else they would have missed and had to come around for another shot."

OK.


"Every time I look into the actions of the pilots on 9/11, I'm amazed at how professional they were every single step of the way. They do not sound like the bumbling fools they've been made out to be."

This is partly why I wonder about the logic of the transponders being turned off (or code changed) during the four flights. Would this really benefit the hijackers since the planes' locations would still be shown on the radar (without specific flight/altitude information); wouldn't the fact that that the transponders had been turned off be a definite indication to ATCs that 'something was wrong' with these flights?

[Ezlivin]

27. Sure.

I'm pretty certain I've asked, but I can't remember the answer(s).

When I was getting my "ticket", one of the big things was managing the flight controls, coupled with making transponder changes as necessary or as directed by center.

I earned my license in the DFW area flying out of the busiest municipal airport in the US (Arlington Muni.) The traffic from DFW can be really intense and flight controllers rapidly bark out their commands. If you screw up and fly into a restricted area without the proper transponder code, you'll be contacted.

One thing to bear in mind is that two military exercises were taking place that day. That's why on the transcripts you'll see flight controllers asking if it was "part of the drill". Plus you need to examine the flight paths of each aircraft. As others have pointed out, the planes fly into "dead zones" before turning back to NY/DC. The conjecture is that it was in these dead zones that the aircraft were swapped with others.

[ROH]

28. Yes, the extent of the wargames, exercises and drills around 9/11

is very interesting.

Spooked911 mentions that there were five NORAD wargames on 9/11:
1) Northern Vigilance
2) Northern Guardian
3) Vigilant Guardian
4) Vigilant Warrior
5) Northern Denial

JackRiddler ( http://www.democraticunderground.com/discuss/duboard.php?az=view_all&address=125x43086 ) comments on:
6) Timely Alert II - an exercise in NJ,
7) the Justice Dept. wargame mentioned recently by Myers in his testimony to McKinney,
8) the NRO plane-into-building drill by the CIA, and
9) possibly another exercise at the Pentagon. He write: "To me, "Timely Alert II" appears to be distinct from the Pentagon's
9/11 "counterterrorism game," though personnel from Fort Monmouth - "the headquarters for White House/Presidential communications" - were involved in both."

Plus Paul Thompson ( http://www.cooperativeresearch.org/context.jsp?item=a091201tripod2 ) mentions the bioterrorism exercise scheduled for 9/12 in NY involving FEMA personnel:
10) Tripod II

Can it really be that all these exercises and the 9/11 attacks are entirely coincidental in their timing?

[spooked911]

33. One thing I've wondered and perhaps you know is how military exercises

intersect with commercial air traffic control.

How often do commercial air traffic controllers have to deal with military exercises? Is this common or rare? And can a large military air exercise confuse an air traffic controller?

Mike Ruppert suggests that as part of the wargames on 9/11, air traffic controllers had artificial blips inserted onto their screens. Do you think this is plausible?

[hack89]

55. War games are conducted in restricted military airspace..

controlled by military air traffic controllers at military installations. FASFAC VACAPES at Oceania, for example, controls military airspace off the coast of VA and NC. FASFAC JAX in Jacksonville controls airspace off of FL. FAA radars are not used to control these exercises - the only role civilian air traffic controller play is routine safety of flight issues as military aircraft transit to the exercise area. They are also responsible to help keep civilian planes out of restricted areas. For these exercises, a strict boundary is drawn between military command and control systems and safety of flight systems (IE air traffic control). It is plausible that artificial contacts would be inserted into military command and control systems but they would never be inserted into air traffic control systems. They would certainly never be inserted into the FAA systems - it would be too dangerous as well as unnecessary.

[Rob Conn]

63. More!!!!

Who ever you are...You better have mighty evidence to go over Mike Rupperts head. You've read the book I assume. Have you? Have you read "Crossing the Rubicon", by Michael Ruppert? Do you recognize the precedents of 'probable cause' and 'reasonable doubt'? The primary elements or our justice system. What do you care about? I want to think you are humane. Show me that you aren't an intelligence program set to trap me psychologically in a perpetual illusion. You could start by sharing your sources for all of the military information that you have expressed. Is there a book I should read. Do tell. - R.C.

P.S. Seriously, for a second, you seem like a pretty stubborn person. Is this true, and can I better understand why you are so focused on playing the role you do in this forum. As I have said, I do not ignore you. But I don't understand where you are coming from at all. Do you ignore me? Are we on the same side? Do you want people to grow? Are you cynical? What's up? Let me know.

[spooked911]

22. These are exactly the points that have made me suspicious of the OS

[Old and In the Way]

39. I'd be interested in what they have to say about Hans Hanjour.

Could a Cessna washout pilot take a 757 at cruising speed and execute a 270 degree turn dropping 7000 ft and not destroy the airframe? I assume no airbrakes were used.

Interesting too that the CR puts such an accurate airspeed on 77...not "over 500MPH", but 530 MPH....hmmm. But that begs another question, how'd it manage to SLOW to 530 MPH if it just dropped 7000 ft? Seems to me it'd been destroyed in mid flight (remember, no airbrakes or flaps) if an inexperienced pilot like Hans attempted this. I've set this Pentagon attack simulation up in my MSFS2002.....it took me 20 attempts of so to figure how the right combination of flaps, brakes, throttle, and bank to not over stress the aircraft. And it took another 10 attempts or so to get it to hit the Pentagon. I've yet to hit it in the way Hans did, though....either too short or overshoot....it's a pretty small window to hit the side of the Pentagon at that speed.

[philb]

41. Group of military and commercial pilots conclude 9/11 by remote control

72 hour symposium of military and commercial pilots organized by Col. Donn de Grand-Pre unanimously conclude 9/11 by carried out by remote control technology

Colonel Donn de Grand Pre (ret), was the top US arms negotiator and dealer to the Middle East under the Ford and Carter administrations.
His book, concludes that the 911 terror attacks were done by government insiders and used remote control technology.

Col. Donn de Grand-Pre organized a symposium in Portugal for a 72-hour non-stop meeting of pilots to try to assess what happened on 9/11. the group of pilots were a wonderful mix of commercial, military and civilian pilots. At any rate, after three days, the decisions were unanimous. And I wrote my 24-page report up and submitted it to the Chairman of the Joint Chiefs. After deliberating non-stop for 72-hours the group has concluded that the flight crews of the four passenger airliners involved in the September 11th tragedy had no control over the aircraft. The planes were taken control of by remote control. And they get into how the military industrial complex clearly, that is elements of it, were in control of this . This is all explained in my books.

Book 2 is "The Viper's Venom," Book 3 which just came out is "The Rattler's Revenge

Portugal News Online- Portugal's National Weekend Newspaper in English 3-08-2002
(discussion of the symposium and of his books can be found on dozens of web sites)

[philb]

42. Some of symposium pilots statements- no hijackers flying the planes

The extremely skillful maneuvering of the three aircraft at near mach speeds, each unerringly hitting their targets, was superb. As one Air Force officer -- a veteran of over 100 sorties over North Vietnam -- explained, "Those birds (commercial airliners) either had a crack fighter pilot in the left seat, or they were being maneuvered by remote control."

Another pilot warned that "we had better consider whether electro-magnetic pulse or radio frequency weapons were used from a command and control platform hovering over the Eastern Seaboard... I'm talkin' AWACS."

Another comment: "If there was an AWACS on station over the targeted area, did it have a Global Hawk capability? I mean, could it convert the commercial jets to robotic flying missiles?

A hotly debated question: Who would be in command of such an Airborne Warning and Control System (AWACS)? Were they Chinese -- Russians -- Saudis -- Israelis -- NATO ? All of these countries possess AWACS-type aircraft. All (except the Saudis) have the capability to utilize electro-magnetic pulsing (EMP) to knock out on-board flight controls and communications of targeted aircraft, and then, to fly them by remote control.

One of the Air Force officers explained that we had already flown a robot plane the size of a Boeing 737 across the Pacific to Australia -- unmanned -- from Edwards AF13 in California to a successful landing on an Aussie base in South Australia. It flies along a pre-programmed flight path, but is "monitored" (controlled remotely) by a pilot from an outside station.

He explained that the London Economist (20 Sep 2001) published comments from the former CEO of British Airways, Robert Ayling, who stated that an aircraft could be commandeered from the ground or air and controlled remotely in the event of a hijack.


Kent Hill is a retired Air Force captain.
He is convinced none of the pilots had control of their aircraft when they were flown into the World Trade Center and the Pentagon. The question then becomes, who was really in control?

"Even if I had a gun at my head, I'd never fly a plane into a building. I'd try to put it in anywhere -- a field or a river --and I'd be searing the hell out of them (the hijackers) by flying upside down first," Hill said.

In fact, the pilot has the best weapon in his hand when threatened with imminent death by a hijacker, namely, the airplane.

Another airline pilot stated. "On hearing a major scuffle in the cabin, the pilot should have inverted the aircraft and the hijackers end up with broken necks."

That none of the four pilots executed such a maneuver points toward the fact that none of them had control of their aircraft, but had been overridden by an outside force, which was flying them by remote control.

As an old and not so bold pilot, I became more convinced that the four commercial jets were choreographed by a "conductor" from a central source, namely an airborne warning and control system (AWACS). They have the electronic capability to engage several aircraft simultaneously, knock out their on-board flight controls by EMP (electro-magnetic pulsing) and assume command and remote control of these targeted aircraft.

[hack89]

60. What happened to the pilots...

or is this also a switch aircraft scenario? Just trying to follow the bouncing ball!

[MrSammo1]

40. The 911 Verses

Listen closely to what Ellen Mariani says in the third MP3 on the page.

(around the 3 minute mark)
What she says fits perfectly!

[spooked911]

52. I listened to that interview and didn't hear what you are refering to.

Are you sure it is Ellen Mariani?

[spooked911]

64. More on the ground effect

http://www.aerospaceweb.org/question/aerodynamics/q0130.shtml

That having been said, let us now explore what happens when an aircraft flies very close to the ground. The phenomenon is most often observed when an airplane is landing, and pilots often describe a feeling of "floating" or "riding on a cushion of air" that forms between the wing and the ground. The effect of this behavior is to increase the lift of the wing and make it more difficult to land. However, what is happening in reality is that the ground partially blocks the trailing vortices and decreases the amount of downwash generated by the wing. This reduction in downwash increases the effective angle of attack of the wing so that it creates more lift than it would otherwise. This phenomenon is what we call ground effect.

An additional bonus of ground effect is called ram pressure. As the distance between the wing and ground decreases, the incoming air is "rammed" in between the two surfaces and becomes increasingly compressed. This effect increases the pressure on the lower surface of the wing resulting in even greater lift.

As you might expect, the impact of ground effect increases the closer to the ground that a wing operates. As indicated in the plot shown below, ground effect typically does not exist when a plane operates more than one wingspan above the surface. At an altitude of 1/10 wingspan, however, induced drag is decreased by half.

Obviously, plane speed will increase the lift as well. So between the high speed, the increased ram pressure and the decreased drag from the ground effect, a Boeing 757 is going to have a LOT of lift and will have a very hard time getting down to six feet off the ground-- which is the MAXIMUM height a Boeing 757 could have been at to produce the damage pattern on the Pentagon.

This, in a nutshell, is the point of the post.

[seatnineb]

65. Excellent work Spooked!

:thumbsup:

[hack89]

66. But having the flaps up significantly reduces the lift ..

so it is "obviously" a wash.

What does this prove? That it wasn't plane? If so - show me a missile that flys six feet off the deck. You are also proving that it couldn't be a missile - if it was launched from an airplane it had to launched at height (to account for the effect of ground effect on the plane and missile drop before its engine/rocket ignites) and will impact with a down angle. If the such a missile could cause the damage seen at the Pentagon then so could a plane impacting at a down angle.

But all this is ridiculous - not one eyewitness saw a missile. Many saw an airplane - I guess they saw an aeronautical miracle (of course your google engineering might be wrong.)

[spooked911]

67. I'm not saying it was a missile, I am saying it was unlikely to be

a Boeing 757 at that speed and that attack angle.

Like I said in the original post, other types of planes are built to fly fast and low to the ground.

Also, wouldn't having the flaps UP cause the nose to go up? And also, I have to wonder how well an amateur terrorist pilot could control the wing flaps. The settings have to be just right for a flat approach.

[Bolo Boffin]

68. How do Boeing 757s ever manage to land?

Seeing as how ground effect doesn't let them within 60 feet of the ground?

This is ridiculous.

[spooked911]

69. It is dependent on the speed. Normally the plane slows down considerably

for landing (normally below 200 mph). If you going too fast, you can't get down that low of the ram effect.

[hack89]

70. Flaps are used to allow the plane to achieve a ...

low speed, nose up attitude for landing - the very purpose of flaps is to allow planes to fly slow without stalling. High speed, level flight does not require flaps - an amateur terrorist pilot would not need to touch the flaps to fly into the Pentagon.

What other planes are you talking about? Single seat fighters don't fly around at 6 feet either - there are very pilots that will fly a high speed tactical airplane below 100 foot even in combat. And you are nuts if you think that there is a remote control system that can accurately control a high speed jet at extremely low altitude. Every remotely control vehicle the US has is a high altitude, low speed system.

Global Hawk has a wing span of 116 foot and a top speed of 350 knots - it still has the ground effect problem plus it is too slow.