01)what is normal and alternate braking in aircraft and what is the difference? 02.what is THS? what is difference between THS and tail plane?

1)Normal Braking : They are some controllable surfaces on the wing called air brakes rise up on the wing to decelerate the velocity of the airflow on the wing (On flight and Land)and also there is a brake at the landing gears of the A/C to decelerate its velocity on the ground while landing(On Land Only).

.Alternate braking:it can be represented into the thrust reverser of the engine which close the secondary flow stream (Represents about80% of the thrust in case of a trubofan engine) to decelerate the velocity of the aircraft and it can be used only on the ground.2)THS : it means trimmable horizontal stabilizer.