A320 reverse
I have been told that the main reason for deploying reverse thrust immediately after landing is to ensure that the lift spoilers deploy.
"After touchdown, when reverse thrust is selected (on at least one engine) and one main landing gear strut is compressed, the ground spoilers partially extend to establish ground contact. The ground spoilers fully extend when both main landing gears are compressed. A small nose down term on the elevators is introduced by the control law."
It also says in the FCTM
"DRY RUNWAY The landing distance calculation does NOT include the effect of thrust reversers."
which seems to back this up. Any ideas?