lowspeed operation modification of pitch angle 356 is effected by moving adjusting rod 360 as shown at 362 each blade is pivotally mounted to the hub by a pivot 364 and is connected to the adjusting rod 360 at lever point 366 although the system shown is a somewhat crude representation of a mechanical adjustment linkage it will be understood by those skilled in the art that any conventional pitch adjustment apparatus may be used to effect the pitch adjustment rotation of the adjustable side propeller in the clockwise direction 368 will result in thrust in the traveling direction 370 fig1 is a perspective view of a side propeller similar to that shown in fig1 and 11 wherein end plates 372 are mounted on end plate support arms 374 of propeller hub 376 the end plate support arms may be shaped to act as conventional screw type propellers and the end plates 372 are properly pitched as described above with respect to fig1 and 11 in order to provide thrust in the traveling direction 378 when rotated in the counterclockwise direction 380 as shown fig1 shows a perspective view of a side propeller with end plates similar to that of fig7 and 8 wherein the end plates 382 are extended so as to contact one another and thereby form a substantially closed cylinder 384 end plate support arms 386 may also be shaped to act as a conventional screw propeller and to properly align cylinder 384 coaxially with propeller hub 388 rotation of the propeller in the counterclockwise direction 390 produces thrust.