All airlines do indeed have diferent names for their doors, and providing the CAA (or local governing body depending on where the airline is registered) have authorised it, it's fine.
Industry standard for a B737-300 for example is
D1L D1R
overwing exits
D2L D2R
And the reason you would have adopted the brace position with feet forward of the knees would be because you are demonstrating the crew position in a rear facing seat.
Feet should always be nearer the tail of the aircraft. So forward facing brace, feet back. Rear facing, feet forward.
It's to stop your feet flying forward in a sharp brake, impact or jolt. Like all rules governed by the CAA, they are as a result of various Air crash investigations, and policies change as a result to improve safety and learn from mistakes.
Another example, the reason you demonstrate the seatbelt unfastening is following a crash where bodies showed sign of trying to open their seatbelts like in a car, and perished as a result. The demo clarifies the difference in the hope they'll remember.
Also lifejackets used to be inflated inside. Until an aircraft ditched and was totally waterlogged meaningmany floated to the ceiling unable to get lower to escape out of a door. Adult lifejackets inflated on a child is different because alot of the air pressure had been released as the child is light and an adult can assist them to dive without too much pressure.
The brace position has been known to save many lives too.
Seat backs remain upright to protect the back and front of the head when bracing and if they are down at all, anything that hits the back of it just gives that little bit more momentum to knock the structure out of place and could collapse a seat exit into the row infront.
Last edited by sixmilehighclub; 22nd Feb 2006 at 00:55.