User manual

DodoSim 206 FSX User Manual

Page 68

Pilot Information: Excessive and unnecessary helicopter noise causes complaints from the public and

contributes to increasing pressure on local airports to close down or cease helicopter operations.

Consideration should be shown by the pilot to reduce the noise generated by the rotors when operating

around airfields and over populated areas by avoiding aggressive manoeuvring and the 85-120 kts and

250-750 fpm descent noise abatement region.

Approaches are performed by reducing forward pressure on the cyclic to adopt the descent attitude.

The collective lever should be lowered to reduce the thrust that would otherwise cause the helicopter to

climb. To ensure that the clutch remains engaged and the rotors do not over-speed, the collective

should be lowered only so far as to induce the desired descent rate.

During the descent, airspeed should be controlled using fore and aft movement of the cyclic. The

descent rate and rotor RPM are controlled using the collective lever, ensuring that the rotor RPM

remains within the green band on the gauge. As airspeed slows towards the hover, the pilot should be

ready to apply power and compensate with left anti-torque pedal. The pilot should consider that the

turbine requires a small time to spool up when the collective lever is raised and anticipate the need to

bring in power early and smoothly to avoid rotor droop and turbine temperature spikes.

Special consideration should be given to avoidance of situations in which Vortex Ring State (VRS) can

develop. The pilot should maintain awareness of the airspeed and descent rate and ensure that the

helicopter is not descending faster than 300 fpm when the airspeed drops below 30 knots.

Pilot Information: Downwind approaches are especially dangerous as low airspeeds can be

encountered much earlier as the pilot concentrates on slowing the helicopter to a hover above a fixed

point on the ground. Therefore approaches should always be performed into the wind whenever

possible.

An ideal approach should end within the rotor’s diameter distance from the ground, where the added

efficiency granted by ground effect reduces the engine power required to the maintain the hover. If it

appears as if the landing will overshoot the intended touchdown spot, the pilot should not attempt to

reduce power further to increase the rate of descent. This could result in VRS with inadequate distance

above the ground for a safe recovery, or leave the helicopter at a height from which vertical auto-

rotation is not possible at such a low airspeed.

4.1.6.2 Landing

If the approach was not performed into the wind, the pilot should turn the helicopter into the wind as it

enters the hover. This will reduce the pilot workload involved in managing the effects of the main rotor

vortices and wind gusts on the tail rotor.

To land, the pilot should concentrate on holding a steady hover and gently reduce the collective lever

until the helicopter begins to descend. If the approach was performed correctly then the helicopter is

already within the ground effect height and so the slight descent rate will not be arrested as the

helicopter descends further.

Hint: The user will find low altitude hovering and landing easier if the 3D virtual cockpit is used and

scaled with the zoom factor to give a wide peripheral view and tilted down so that both the horizon and

the view through the chin bubble are visible.

The pilot should avoid the temptation to raise the collective lever to cushion the landing unless it is

apparent that damage or injury will occur otherwise. Abrupt or excessive movements of the collective

lever will make the helicopter more difficult to control as the pilot also has to manage the varying tail

rotor thrust in response to the differing torque demands.