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To: mach.08; jlogajan; Sgt_Schultze; Timesink; JohnFiorentino; acehai; *TWA800_list; Spirited; Rokke
Think of it this way... the plane was climbing by the appliation of a force that caused it to rise at approximately 33 feet every second. This force is the TOTAL LIFT of all wing surfaces.

For our purposes we will assume that the VECTOR of this force is straight up. The aircraft is subject to gravity and, absent a counteracting force, will fall 32 feet in the 'next' second. The wing lift force is actually sufficient to overcome that 'fall' AND to also to lift it another 33 feet in that 'next' second, a total of 55 feet per second of force straight up.

Another force being applied to the plane is the drag of the atmosphere's fluid flowing into, around, and behind all surfaces of the aircraft. To maintain forward speed at level flight this force is counteracted by the thrust of the engines that is kept in equilibrium with the TOTAL drag. Drag increases with speed and decreases with altitude. Let's assume that TWA800 was equipped with the most powerful Rolls Royce engines Boeing mounts on that airframe (it wasn't) which are rated at 80,600 LBS of maximum thrust each. Let's further assume (conservatively) that TWA800 had its throttles set at 50% and the engines were producing 40,300 Lbs of thrust or a combined total thrust of 161,200 Lbs to overcome 161,200 Lbs of drag.

Now we have the initiating event. The nose is blown off, the control signals to the engine are instantly cut off, and the engines immediately revert to idle speed (per Boeing) producing minimal thrust. The aircraft, responding to the sudden loss of the nose and power, pitches upwards on the fulcrum of its center of gravity. The drag (if the plane were intact) is the equivalent of all four engines thrusting in the OPPOSITE direction at 161,200 Lbs! The plane starts decelleration. The pitched up attitude increases forward drag by some unknown but not insignificant amount. The vector of the lift is NO LONGER STRAIGHT UP... it is instead angled somewhat backwards and adds to the decelleration. The wind of forward motion no longer flows over a conical nose but rather is caught on a jagged fuselage skin, adding to the force torquing the plane about the fulcrum of the CoG. The tail surfaces are also dropped into the windtream and will, being on the other side of the fulcrum add a countering vector to the massive forces working to pitch the plane up. However, the tail is designed to be either slightly reverse lift or nuetral, it will stall even earlier than the main wing.

Remember the lift? It is falling off rapidly as the angle of attack is increased and the speed is decreasing. Gravity's acceleration vector is STILL straight down. The drag's force vector is still straight back through the direction of travel... both still being applied to the aircraft. There are no forces being applied any longer to counteract any of these.

No more energy is being added to the system. The disconnected parts of the plane still have a lot of kinetic energy but they can only lose energy at this point. The momentum is retained by all parts proportionate to their mass. All of those parts are subject to the forces of gravity and those applied by drag and friction. What energy the plane had in its momentum is rapidly being applied to lift or trying to overcome drag... it is a losing battle. If the wing miraculously maintains a proper angle of attack, the energy momentum will be exchanged for altitude... but the wings don't and go quickly to stall... no lift at all.

All energy contained in the momentum of the system will be applied in trying to overcome the drag. Gravity is INSTANTLY pulling the entire shebang downward at an acceleration of 32 feet every second. The Upward momentum vector is overcome fairly quickly after lift is lost... less than one second. Without lift, the aircraft will fall 64 feet in the next second and 96 in the following... accelerating at 32 feet per second until it reaches terminal velocity of about 450 feet per second in 15 seconds. It will have fallen 3810 feet in the 15 seconds after stall.

The forward momentum is rapidly being used up by drag. Asuming the plane mantained lift for 3 seconds after the IE, and not allowing for any decelleration or loss of lift, the MOST the plane could have risen is a mere 100 feet... but let's give it 200.

0 seconds - IE @ 13,800
3 seconds - stall and start of ballistic fall @ 14,000
18 seconds - terminal velocity - ~450 ft/sec. @ 10,190
24 seconds - Massive fireball - fuel/air explosion @ 7,300
41 seconds - Ocean impact - 0 feet.

That's what the radar said... loss of signal to first ocean impact - ~38 to 44 seconds.

If we add in either climb scenario we have to add 18 seconds for the climb... and from 3 to 9 seconds more for the fall. The CIA scenario needs 27 more seconds than can be accounted for and the NTSB scenario needs 21 seconds more than can be accounted for.

Sounds like the new Accounting math being used by Enron and its ilk.

Finally:

"Ballistic Fall.
The captain of the NOAA research ship Rude entered Flight 800's last secondary radar position, speed, heading and gross weight into his computer and it predicted the landing point by calculating a ballistic fall. He went to that spot and immediately found the main wreckage including the fuselage, wings and engines. "

Unless you want to repeal the law of gravity, there literally is not enough time for ANY climb at all.

Period.

192 posted on 07/31/2002 2:52:06 AM PDT by Swordmaker
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To: Swordmaker
Excellent analysis.
193 posted on 07/31/2002 2:58:21 AM PDT by FormerLurker
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To: Swordmaker
absent a counteracting force
Which could be either lift or momentum.

"Let's further assume (conservatively) that TWA800 had its throttles set at 50%Its throttles were at max, but that's irrelevent. The NTSB did simulations based on throttles off, climb thrust and max thrust and found there was little difference.

the equivalent of all four engines thrusting in the OPPOSITE direction at 161,200 Lbs!
What? How are windmilling engines in idle producing 161,200 lbs of thrust in any direction?

There are no forces being applied any longer to counteract any of these.
Remember the lift? It doesn't disappear until the wings stall, which doesn't happen instantaneously even in your scenario.

All energy contained in the momentum of the system will be applied in trying to overcome the drag. Gravity is INSTANTLY pulling the entire shebang downward at an acceleration of 32 feet every second.
That's not even true in the scenario you just described. The wings did not INSTANTLY stall, and its upward momentum is not instantly reversed by the forces of gravity. In fact, the upward momentum initially increases by the aircraft's initial pitch up.

What energy the plane had in its momentum is rapidly being applied to lift or trying to overcome drag... it is a losing battle.
You are contradicting yourself here, because you just got done saying gravity is instantly pulling the aircraft downward at 32ft/sec^2. That can't be true if their as any lift at all.

but the wings don't and go quickly to stall
It took at least 3 seconds. And that is 3 seconds of a massive infusion of upward momentum based on the increasing pitch.

All energy contained in the momentum of the system will be applied in trying to overcome the drag.
You are contridicting yourself again. You've forgotten your previous statements about lift.

Gravity is INSTANTLY pulling the entire shebang downward at an acceleration of 32 feet every second. The Upward momentum vector is overcome fairly quickly after lift is lost
These statements cannot both be true.

The Upward momentum vector is overcome fairly quickly after lift is lost... less than one second
Where is your proof lift was lost in less than one second?

You've proceed to disprove your entire theory with your table of data. After repeating several times that lift is lost instantly, your table shows the stall occurs at 3 seconds. Then, you completely ignore any momentum gained in those 3 seconds and assume there is no upward vector when you state the ballistic fall starts immediately after the stall. I don't know how you calculated terminal velocity since nobody knows the drag coefficient of a 747 without a nose is. Finally, an aircraft with wings doesn't fall ballistically. Even if stalled. Neither does a sheet of paper, a leaf, or the famous noseless balsa wood glider

195 posted on 07/31/2002 8:27:38 AM PDT by Rokke
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