The spreading operation requires the same conditions as the fold operation. The primary exception is that the blade fold switch is in the SPREAD position. Pressure is sent through the motor-operated safety valve and through the positioning unit pressure reducers. Pressure is sent to the blade positioner drive unit for rotor brake disc disengagement and the engagement of the rotor brake. With the rotor brake on and the blade fold valve energized, 3,000 psi hydraulic fluid is sent through the rotor coupling. From the coupling, pressure is sent to the damper-positioners. The damper-positioners drive the blades against their autorotative stops. Pressure is then sent to the blade fold cylinder. The blade fold cylinder operates the gear sector and spreads the blade. As the blade starts to spread, the lock valve solenoid is de-energized, releasing fluid in the rotary-wing head.

When the blade is completely spread, hydraulic fluid is sent to the blade lock cylinder, engaging the blade lockpin. Engagement and locking of the blade lockpin causes the internal sequencing mechanisms to direct pressure to the control lock cylinder. The control lock cylinder, in turn, locks the controls. The spread sequence is completed. The FOLD PWR, BLADE SPREAD, and SAFETY VALVE OPEN warning and indicating lights should be lit.