I do love how he mentions that the difficult part of the tea-pouring-during-a-roll was pouring the tea back-handed... I guess it all comes down to a matter of perception, as with so many things in life.

I don't really understand how this works. The article mentioned something about inertia... So gravity moves the object in a downward direction... and then, when the plane is flipped, it keeps moving in that direction -- which is now up? I guess that the effect would "wear off" after awhile? So if you kept flying upside down the tea would eventually fall, right?

Pour a glass of water and hold it loosely between your thumb and index finger (tightly enough that it won't fall, but loose enough that it can swing freely). Then take it outside and swing it in a big vertical circle. You'll be surprised how slowly you can swing it while still keeping the water in the glass.

Just like the glass of water though, if the plane were to stop rolling, the tea would immediately spill. It has nothing to do with "bending gravity", simply the reactive centrifugal force imparted by the turn itself.

Think of the wings as the glass and the fuselage as the tea in the glass. The pilot's glass of tea is imitating what the wings and fuselage that contain the glass are doing.

If the pilot turns the plane at the correct rate, it's a 1 G maneuver. If he turns a little too fast (like spinning your arm too fast) the downward acceleration relative to the fuselage becomes greater than 1 G. If he turns too slowly, the downward acceleration is less than 1G and the tea might spill.

I use the term downward acceleration because "G Force" is not a term that physicists like to use.

Centrifugal force is also used to achieve the concept called artificial gravity, which is the reason why characters in Star Trek walk around like normal in their starships.

Some sci-fi has cylindrical ships or space stations spun for gravity, but in Star Trek they have "gravity plating", so the ships don't have to spin. A convenient plot device to cover the fact that they didn't have the budget to shoot every episode aboard the vomit comet.

What? No it isn't. http://memory-alpha.org/wiki/Gravity_plating

The same reason a pail of water swung around your head doesn't spill. The path cut by the rolling plane in this case is a spiral, as it's a barrel-roll rather than an aileron roll.

So yes, if you stopped at the top of the roll, the liquid would indeed fall out. The reason it doesn't is that the plane is continuing to roll, and the acceleration of the plane away from its upside down position is greater than the acceleration due to gravity. The liquid is "falling" at 9.8 meters per second, but the plane - and hence the glass - is being pushed at a faster rate.

Both the plane and its contents experience the same acceleration due to gravity. Unless the plane is accelerating, the occupants will experience weightlessness (e.g. vomit comet). Of course the plane is accelerating - in straight and level flight this acceleration counteracts the acceleration due to gravity. This acceleration (lift) is provided by the wings, which don't move, so it is always in the same direction (in the plane's frame of reference).

So if you kept flying upside down the tea would eventually fall, right?

No. Eventually the plane would hit the ground, since it is not only falling but also generating "lift" in a downwards direction.

Bob was doing this before the designers of the f-16 were a sparkle in their parents eyes. Bob knew Orville Wright and Charles Lindbergh as friends.

youtube up the video of him flying the f-86 sabre if you want to be stunned.

The F-86 video: http://www.youtube.com/watch?v=TRt6UnNzR6I