Abstract: A method and apparatus are provided for controlling rocket and/or jet engine thrust by producing a strong electric, magnetic or electro-magnetic field, and applying the field to deflect the thrust stream as it exits from the engine until the desired thrust vector is obtained. The method of modifying an exhaust plume produced by combustion of fuel and ejected from an exhaust nozzle of a vehicle comprises the steps of: generating a field and producing a flow of electrons across the stream of the exhaust plume for interacting with charged ions and particles in the exhaust plume to deflect the direction of the exhaust plume, and controlling the magnitude and extent of deflection to steer the vehicle to a desired course.