AF447 final crew conversation - Thread No. 1

[awblain]

g=1 when falling with no acceleration.

You feel weightless only when you're accelerating down. When you're falling at a steady speed you feel 1g.

The elevator comment is absolutely right: when cruising between floors, you can't tell you're moving. The light and heavy gut feeling only comes when the elevator speeds up or slows down.

Astronauts are free-falling continuously around the earth: the earth is just curving away so they don't hit it. They are accelerating towards the centre of the earth under gravity at 1g, but so is the space station, so they feel neither weight not a reaction force from the walls.

If you're falling steadily, with weight balanced by drag, and so no acceleration - either when `free-fall' parachuting at terminal velocity, or aboard AF447 - your gut feels like it would sitting on the couch.

Added:

Although you would feel like you were sitting on the couch, it would be a couch tilted back against the wall.

A plumbline would show your attitude, although you'd need a hanging spring balance to confirm there was no acceleration to confuse the result. There may also have been enough shaking to make that ineffective.

If the captain had clung to a handle rather than strapping into a jumpseat, that might have been enough to convince him of the nature of the situation, as his feet would have dragged aft compared with his head to balance.