From: Ian Goddard (Ian@Goddard.net)
Date: Mon Feb 15 1999 - 22:23:31 MST
I have to blame myself for not having more
effectively translated the CIA scenario, I
assumed it was know more than it is.
Respondents don't understand what it is
so we're all talking past each other.
We're not talking about a plane that was on a
forward/horizontal vector and that translated
into a downward vector (but keep in mind that
horizontal and vertical velocity are independent,
but that's not a matter here). The CIA scenario
says that the plane shot upwards 3,200 feet
in 20 seconds after the nose came off. Drawing
a graph finds that's an angle of attack around
16 to 18 degrees.
Anyway, the point is that the jet shot up like
you throw a ball up, and reached a peak, would be
at rest there, and then fell. That's the CIA scenario.
More comments...
At 10:51 PM 2/15/99 -0500, Michael Lorrey wrote:
>Not necessarily. A plane can be stalled and still be moving forward at high
>velocity. It is the angle of attack which matters when it comes to lift, not
>speed. Once it blew in half, the front section was front heavy and acted
like a
>lawn dart, translating its forward speed into downward speed.Calculate in its
>forward velocity (probably around 300-400 mph) while climbing, being
translated
>over by the change in angle of attack to downward velocity....
IAN: Horizontal velocity is independent of
vertical velocity, what that means is that
you don't translate forward velocity into
downward velocity. Basic kinematics, but
again, not a factor in the CIA scenario.
Speed does play a role in lift. For
example,tilt a wing at any angle at
0 mph, and it gets no lift. Give it
some forward speed, and it has lift.
The front end blew away, and the mid-to
rear sections got rear heavy causing a
pitch up, which the math shows will cause
a fatal stall in under five seconds, but
the CIA says it caused the noseless jet
to shoot upwards looking like a rocket.
Witness say that the plane rolled and fell
like a rock, which is exactly what happened
to PAN AM 103 after it lost its forward section.
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