Although they’re seldom larger than a few inches in diameter and a couple inches in length, Formsprag overrunning clutches, also known as sprag retainer assemblies, one-way clutches, or freewheels, perform some of the most critical functions on many types of aircraft.

Formsprag sprag clutches permit drive during normal operations and autorotation during emergency situations. To allow for power redundancy, these clutches can be installed on all rotor/fan drive motors to enable backup drives to engage as needed.

Formsprag’s unique Formchrome® process diffuses chromium into the surface of the sprags in the clutch creating a surface hardness that translates into extended wear life of 180% over Non-Formchrome sprags.