Refer to figure 11-1 (position 1). From level flight at the manufacturer’s recommended airspeed, between 500 to 700 feet AGL, and heading into the wind, smoothly, but firmly lower the collective pitch control to the full down position, maintaining r.p.m. in the green arc with throttle. Coordinate the collective movement with proper antitorque pedal for trim, and apply aft cyclic control to maintain proper airspeed. Once the collective is fully lowered, decrease throttle to ensure a clean split of the needles. After splitting the needles, readjust the throttle to keep engine r.p.m. above normal idling speed, but not high enough to cause rejoining of the needles. The manufacturer often recommends the proper r.p.m.

At position 2, adjust attitude with cyclic control to obtain the manufacturer’s recommended autorotation or best gliding speed. Adjust collective pitch control, as necessary, to maintain rotor r.p.m. in the green arc. Aft cyclic movements cause an increase in rotor r.p.m., which is then controlled by a small increase in collective pitch control. Avoid a large collective pitch increase, which results in a rapid decay of rotor r.p.m., and leads to “chasing the r.p.m.” Avoid looking straight down in front of the aircraft. Continually cross-check attitude, trim, rotor r.p.m., and airspeed.

At approximately 40 to 100 feet above the surface, or at the altitude recommended by the manufacturer (position 3), begin the flare with aft cyclic control to reduce forward airspeed and decrease the rate of descent.

Maintain heading with the antitorque pedals. Care must be taken in the execution of the flare so that the cyclic control is not moved rearward so abruptly as to cause the helicopter to climb, nor should it be moved so slowly as to not arrest the descent, which may allow the helicopter to settle so rapidly that the tail rotor strikes the ground. When forward motion decreases to the desired groundspeed, which is usually the slowest possible speed (position 4), move the cyclic control forward to place the helicopter in the proper attitude for landing.

The altitude at this time should be approximately 8 to 15 feet AGL, depending on the altitude recommended by the manufacturer. Extreme caution should be used to avoid an excessive nose high and tail low attitude below 10 feet. At this point, if a full touchdown landing is to be made, allow the helicopter to descend vertically (position 5). Increase collective pitch, as necessary, to check the descent and cushion the landing. Additional antitorque pedal is required to maintain heading as collective pitch is raised due to the reduction in rotor r.p.m. and the resulting reduced effect of the tail rotor.

Touch down in a level flight attitude.

A power recovery can be made during training in lieu of a full touchdown landing. Refer to the section on power recoveries for the correct technique.

After touchdown and after the helicopter has come to a complete stop, lower the collective pitch to the full-down position. Do not try to stop the forward ground run with aft cyclic, as the main rotor blades can strike the tail boom. Rather, by lowering the collective slightly during the ground run, more weight is placed on the undercarriage, slowing the helicopter.

A power recovery is used to terminate practice autorotations at a point prior to actual touchdown.

After the power recovery, a landing can be made or a go-around initiated.

At approximately 8 to 15 feet above the ground, depending upon the helicopter being used, begin to level the helicopter with forward cyclic control. Avoid excessive nose high, tail low attitude below 10 feet.

Just prior to achieving level attitude, with the nose still slightly up, coordinate upward collective pitch control with an increase in the throttle to join the needles at operating r.p.m. The throttle and collective pitch must be coordinated properly. If the throttle is increased too fast or too much, an engine overspeed can occur; if throttle is increased too slowly or too little in proportion to the increase in collective pitch, a loss of rotor r.p.m. results. Use sufficient collective pitch to stop the descent and coordinate proper antitorque pedal pressure to maintain heading. When a landing is to be made following the power recovery, bring the helicopter to a hover at normal hovering altitude and then descend to a landing.

If a go-around is to be made, the cyclic control should be moved forward to resume forward flight. In transitioning from a practice autorotation to a go-around, exercise care to avoid an altitude-airspeed combination that would place the helicopter in an unsafe area of its height-velocity diagram.