Hovering Autorotation

The sequence

1. Engine failure recognized — engine note changes, low-rotor warning may sound, helicopter starts to yaw with torque loss.
2. Lower collective immediately — flat pitch on the blades preserves rotor RPM. Don't pause; don't think about it; do it.
3. Apply right pedal (US CCW rotor) — without engine torque there's no leftward yaw to counter, so the tail rotor's leftward thrust is now unbalanced. Right pedal counters.
4. Cyclic level — keep the helicopter level; do not let the nose drop or pitch up.
5. Settle to the ground — the helicopter falls in a controlled descent. From a 3-ft hover this happens in under a second. From a 10-ft hover, slightly longer.
6. Cushion with collective — at a few feet AGL, smoothly raise collective to convert rotor inertia into lift. Not a fast yank — a smooth pull. Touch down on flat skids.
7. Collective at the floor after touchdown — once on the ground, lower collective fully so the helicopter doesn't try to fly again on residual rotor energy.

Why "lower collective" is non-negotiable

Without engine drive, the rotor spins down quickly under load. If the blades are at high pitch (high angle of attack producing lift), the air decelerates them rapidly — within a second or two, rotor RPM drops below the value at which you can flare or cushion. From there, the helicopter is no longer a controlled aircraft; it's a falling object with spinning blades.

Flat pitch reverses this. With low blade pitch, the airflow during descent passes through the disc with minimal drag, and the rotor maintains usable RPM. The collective-down reflex preserves the only energy reserve the rotor has left. Get it down within the first second and you keep the rotor; pause and you don't.

The cushion — timing matters

Cushion too early (at 6+ ft AGL): you bleed off rotor RPM before touchdown, the cushion runs out, and you drop hard the last few feet. The helicopter takes the impact through the skids; the rotor system takes the impact through the mast.

Cushion too late (after touchdown): you slam into the ground at full descent rate. Damage ranges from cosmetic to fatal depending on aircraft and rate.

The right timing: as the helicopter descends through approximately 3 ft AGL on a low hover-auto, begin the smooth collective pull. The cushion peaks around 12 inches AGL. Touchdown is firm but controlled. Practiced students can do this with 6-inch precision; the maneuver is crisp because it has to be.

Why this is the most-practiced emergency

Engine failures at low hover are statistically more common than failures at cruise — most arise from fuel exhaustion, fuel contamination, mag drops on takeoff, or carb ice during the run-up-to-hover transition. The phase of flight from "hover check" to "transition through ETL" is the single most engine-failure-prone segment.

That's why every PPL student practices hovering autos until they're reflexive. Your instructor will roll throttle to idle in a hover with no warning, and your hand has to be on the way down before your brain has finished registering what happened. Reflex is the goal — there's no time to think.

Robinson, Bell, MD, and most training operators include hovering autos in every recurrent training cycle precisely because the skill perishes if not practiced. A hover-auto reflex you don't drill regularly may not be there when you need it.

Common mistakes

• Hesitating on the collective — even a half-second pause loses critical RPM. Drill the move until it's automatic.
• Forgetting the pedal — without the right pedal input on a CCW rotor, the helicopter yaws left as it descends. Adds workload at the worst moment.
• Cushioning too early — Phase-1 students often cushion 4-5 ft up, then drop hard.
• Cyclic input during descent — keep the cyclic still during the brief descent. Trying to "fly" the helicopter to a slightly different spot wastes attention and rotor RPM.
• Not lowering collective on the ground — residual rotor energy + raised collective can produce a small hop after touchdown.