apogee
decelerate
delay
drag
ejection
gravity
igniter
launch
propellant
unbalanced force
thrust
action
reaction
balance point
velocity
shock cord
featherweight
force
glide
helicopter
mass
motion
parachute
| accelerate apogee decelerate delay drag ejection gravity igniter launch propellant unbalanced force thrust action reaction balance point | fins velocity shock cord featherweight force glide helicopter mass motion parachute |