With the unique Kiwiprops™ design approach the blades are free to rotate on their individual shafts. When incremental speed is obtained from the sails when motor sailing, the blades will " see " what is effectively an increase in pitch as speed builds above what you would obtain under motoring alone and automatically adopt a higher pitch position.

Thus when motor sailing - the pitch automatically increases to compensate for any additional boat speed.

Sailing speed can thus be augmented with relatively low engine rpm removing the need to increase engine rpm to generate thrust as vessel speed increases.

Only the Autoprop™ and the Kiwiprop™ designs allow for this very useful functionality.