Some jerk has redesigned the primer so that the flame misses the propellant!
Its final fall was due to the introduction of gunpowder as a propellant.
The suit had been torn in the fall, and some propellant had gotten in through the rents.
The propellant was taking the rocket almost out of sight when the fuse fired it.
Compressed air was the propellant for the Zalinski dynamite ...