H-92/Emergency Procedures

SECTION 3. EMERGENCY PROCEDURES

1 AUTOROTATION

In the event of a power failure above 50 feet AGL,, apply the following procedures:

1. Lower collective completely. Monitor rotor RPM in descent and raise collective slightly if rotor RPM becomes too high. You may need right pedal as you lower the collective due to the reduction in torque from the engine.
2. Maintain a forward speed of 50-60 mph until approximately 50 feet AGL.
3. At approximately 50 feet AGL, begin a cyclic flare by pulling back on the cyclic.
4. At about 10 feet AGL, level the helicopter and pull collective to slow down the descent.

2 HOVERING AUTOROTATION

In the event of a power failure during a hover, the following procedures apply:

1. Apply immediate right pedal to hold heading and maintain collective until helicopter begins to sink
2. Apply full up collective as helicopter begins to sink
3. Lower collective once helicopter is fully on the ground

3 LOW-RPM CONDITION

Low rotor RPM is a dangerous condition that can occur when RPM is not carefully monitored or maximum power limitations are not observed. If the RPM is allowed to decay too far, recovery may be impossible. This aircraft is equipped with a low RPM warning system consisting of a warning light and a horn. The light and horn will activate when rotor RPM is below 93% whenever the collective is not full down.

In the event of a low RPM condition, the pilot should lower the collective until normal RPM is achieved. If the helicopter is too low or over unsuitable terrain, the pilot can attempt to "milk" the collective, with small up-down movements of the collective in an attempt to recover rotor RPM. However, the best approach is to not get into a low RPM condition in the first place.

4 VORTEX RING STATE

Vortex ring state occurs when a helicopter descends into its own downwash resulting in a loss of lift. It can occur when attempting to apply power during a vertical descent. To recover, the pilot should lower the collective and apply forward cyclic to regain airspeed. Since the recovery can require a significant loss of altitude, the best practice is to avoid encountering this condition, particularly when close to the ground. Practice vortex ring state recovery should be performed with sufficient altitude to be able to complete the maneuver.

See the Shergood Flight System for a more complete description of vortex ring state.

5 SINGLE ENGINE OPERATION

In the event of an engine failure, the S-92 is capable of sustained flight on one engine, however much more care must be taken to avoid low RPM conditions. The torque gauge on the PFD should be monitored while raising collective with care not to exceed the blue line.