Friday, December 18, 2015

06 - What Planes?

Okay, there's three videos in a row here that follow one behind the other,  use the double forward triangle to move to the next one then the one after that.
(I just noticed that the "next video" button doesn't appear unless you click "watch on Youtube" so I've included the other two here.)
Here's what you will learn:  (see below)

Air craft structures are relatively strong, but that's only when they are compared to the forces exerted on them by air.  An aircraft will handle air flows in the range of 0 to ~500 feet per second.  Even then, the aircraft's attitude must be kept inside certain angles of attack,  with speeds reduced as the air gets denser.  Outside a prescribed set of attitude parameters and the aircraft will be destroyed by the air flow.

Steel, on the other hand,  will withstand the force of air up to 10,000 feet per second,  at the low end and 30,000 feet per second at the high.  That's what explosives produce to dismantle steel members.

So the question becomes,  can an aircraft which can only withstand the forces of air moving at less than 800 feet per second,  actually cut through a steel member that can withstand the force of air moving at over 10,000 ft/sec. ?   Obviously not.  This is because the aircraft cannot produce the same force as air would,  if the air were to be moving at tens of thousands of feet per second.  Because it cannot withstand such forces,  it cannot produce them,  because it would disintegrate before the forces could rise to that level.  It's why an egg thrown at a concrete wall will not penetrate it.  The eggshell crumbles long before it can exert enough force to damage the concrete.

When the aircraft hits the side of the steel building,  it crumbles and breaks apart,  by the exertion of forces against the steel,  equivalent to air moving at only 800 to 1,000 ft/sec.  While the steel is able to resist forces ten to thirty times greater.

Watch all three videos because,  each one reveals something different.
07 - The Key

08 - The Psy-Opera