Student or Learner
What does "missile off the rail" mean? Not following its usual trajectory according to the laws of physics?
"In order to maneuver sufficiently from a poor launch angle at short ranges to hit its target, missiles are now employing gas-dynamic flight control methods such as vectored thrust, which allow the missile to start turning "off the rail", before its motor has accelerated it up to high enough speeds for its small aerodynamic surfaces to be useful."
Yes, something like that. According to the trajectory it would take going straight off of its launcher. Like it was riding on rails like a train. They are able to maneuver it so it moves off of its "rails."