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To: EggsAckley
The gubment claims TWA 800 climbed some 2800 feet AFTER the nose separated from the rest of the aircraft. That possibility is something akin to pigs flying, but they continue to make that assertion with a straight face.
12 posted on 07/27/2002 10:50:40 AM PDT by kylaka
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To: kylaka
Please comment on #16. jlogajan explains how the the plane climbed once the nose dropped off.
24 posted on 07/27/2002 2:41:20 PM PDT by secretagent
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To: kylaka
There's hardly any point trying to explain aerodynamics to a committed tin-hatter who can't even spell "government."

But I'm going to try anyway.

When an airplane is in level flight, the forces working on it are in a certain equilibrium. The lift (which comes mostly from the wings) is equal to the weight. The thrust (which comes from the powerplant[s]) is equal to the drag (which comes from several different sources).

In conventional monoplanes (which includes everything from a Cessna 172 to the 747-400 and beyond) the wing provides a center of lift which is slightly aft of the center of gravity. This ensures that the center of pressure is aft of the center of gravity (necessary for stability). What that means, is that if these planes did not have a horizontal tail, they would nose down in normal flight.

Well, we know that planes don't always nose down uncontrollably in normal flight. Why not? The horizontal tail, either because of its position, its inverted airfoil (vis-a-vis a wing), or its negative incidence, or some combination of these design features, provides a nose-up push -- what we who grasp these things call a "pitching moment" -- that counteracts the wing's tendency to pitch the plane nose-down around the center of gravity.

What happens, if as happened to 800, when a catastrophic event, an explosion, causes a lot of the structure to shear off of the nose of the plane? These things:

  1. The aerodynamics change as the streamlined nose is disrupted. This creates a lot of drag acting on the end of the plane. IF the parts are shorn away clear, this force doesn't move the plane itself in any particular axis, but it decelerates it (thrust and drag aren't in equilibrium any more, are they?) and also by applying a lot of force to the now-blunt cut-off end of the plane, can amplify any other pitch or yaw moment that comes from another source.
  2. The source of the pitch moment is easy to find. Remember that the stability of the plane traces to the center of lift, the center of gravity, and the offsetting nose-up moment imparted by the horizontal tail. But with a lot of structure gone, all from the nose area, and forward of the center of gravity, the center of gravity moves abrubtly to the rear. If the center of lift is forward of the CG now, that would impart a strong pitch-up. If it is still aft of the CG, the pitch-up coming from the tail is no longer "just enough" to offset the wing's pitch-down moment, it is now "too much," and you have a milder pitch-up.
So what carries the crippled, decelerating wreck 3000 feet higher? All it takes is a mild nose-up pitch amd inertia. A lot of inertia in a half million pound airplane. A mild nose up pitch is inevitable in a plane that has just lost its nose. Hey, that's exactly what the radar showed, too.

Nothing here is beyond middle school science. Unfortunately science makes few inroads on minds that are slaves to irrational belief systems. A conspiracy theory is attractive to such minds, because it ties up all the loose ends (if the evidence doesn't fit the theory, you selectively discard and manufacture evidence to fit -- the 800-missile crew perfectly illustrates this).

Then again, 800 wasn't straight and level in the first place. It was climbing anyway, so its energy vector was above the horizontal to begin with.

You apparently think that pieces of an airplane demolished by an explosion, a midair, or a weather encounter, instantly shed all the energy they contain and fall straight down. Nope. That is a child's understanding of objects in motion, and a rather dim child at that.

Sigh. I don't know what I hope to achieve. We live in a nation where most people believe that the Air Force has aliens in the freezer and nuclear reactors are the same thing as nuclear weapons. If there is a reason to hate the government, it's the crappy education that leaves people vulnerable to such eruptions of folly.

d.o.l.

Criminal Number 18F (Time to check the temp on E.T.)...

PS you can test this yourself on one of those styrofoam 747s they sell in toy stores -- you know, the big glider. Trim it so it flies straight when you throw it. OK, now take a knife and cut it off bluntly in front of the wing. Without altering the trim, throw it. It tries to loop up and stalls.... a real 747 would be stressed enough to continue breaking up. -C18F

131 posted on 07/30/2002 1:23:51 PM PDT by Criminal Number 18F
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To: kylaka
James Kaelstrom has a lot to answer for. He CONVINCED Rush Limbaugh that all of those witnesses were wrng....and then he retired. He's a Liar and a coward
496 posted on 08/10/2002 9:28:03 AM PDT by Ann Archy
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