If you wish to contribute or participate in the discussions about articles you are invited to join SKYbrary as a registered user
From SKYbrary Wiki
When installed, reverse pitch is a pilot selectable feature of a constant speed or variable pitch propeller which allows the blade pitch to be decreased to a negative value. Negative pitch angles result in the thrust generated by the propeller being directed forward against the direction of motion of the aircraft. Use of reverse pitch decreases landing distance, improves aircraft stopping performance in the event of a rejected take off and, when permitted by the Aircraft Flight Manual (AFM) enables the aircraft, whilst on the ground, to be reversed under its own power.