An elongated fluid dynamic water jet type of propulsion body receives an inflow
of fluid through inlet openings for entry into a jet propulsor from which an outlet
jet emerges for passage through an internal transition passage to an exit end between
two pairs of horizontal flaps hinged to the body at the exit end for angular displacement
about parallel spaced horizontal axes from horizontal neutral positions. Four pair
of flaps are pivotally mounted within the transition passage for angular displacement
about parallel spaced vertical axes from neutral positions. Actuators inside of
the propulsion body connected to the flaps are selectively controlled to impart
in-phase angular displacement to all of the flaps about their horizontal and vertical
axes from the neutral positions for directional steering by angular deflection
of the jet exit outflow from the exit end of the body. To reverse propulsion, only
the actuators for the horizontal flaps are activated in an out-of-phase mode to
effect angular displacement of each pair of the horizontal flaps in opposite directions
into engagement with each other thereby blocking jet outflow from the exit end
of the body causing a directional reversal of the propulsion jet by outflow from
openings formed in the body rearwardly of the exit end.
