reversible-pitch propeller
reversible-pitch propeller
[ri′vər·sə·bəl ¦pich prə′pel·ər] (mechanical engineering)
A type of controllable-pitch propeller; of either controllable or constant speed, it has provisions for reducing the pitch to and beyond the zero value, to the negative pitch range.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.