134 into an engaged position in which engagement pin 134 is forced into and held in engagement with one of engagement grooves 136 138 140 142 as noted above in the exemplary illustrating of fig3 the aircraft flaps are in the full position as a result engagement pin 134 is held in engagement with engagement groove 142 of detent plate assembly 132 since engagement groove 142 is associated with the full aircraft flaps position similarly engagement groove 140 is associated with aircraft flaps position 2 such that when engagement pin 134 is in engagement with engagement groove 140 the aircraft flaps will be commanded to flaps position 2 similarly engagement groove 138 is associated with aircraft flaps position 1 such that when engagement pin 134 is in engagement with engagement groove 138 the aircraft flaps will be commanded to flaps position 1 similarly engagement groove 136 is associated with aircraft flaps position up such that when engagement pin 134 is in engagement with engagement groove 136 the aircraft flaps will be commanded to flaps position up when a releasing force is applied to flap knob 104 and flap knob 104 is sufficiently depressed against the bias force of compression spring 130 engagement pin 134 is removed from engagement with one of engagement grooves 136 138 140 142 such that flap knob 104 can be moved into rotation within knob slot 106.