Transition altitude & stuff

Question 1

Transition altitude

Answer 1

Set by each state.
Altitude in which you enter transition layer.
This is where you switch from local pressure, to SPS, 1013.
ASCENT

Question 2

Transition layer

Answer 2

Layer of air, say 500ft, where you switch to SPS.

Adjustment period.
Not fly level here.

Question 3

Transition level

Answer 3

The top of the transition layer. Where you switch from SPS to local pressure (given by atc).

DESCENT