Figure 13-1: The straight-ahead autorotation
The helicopter will now begin to descend vertically. Apply collective pitch as necessary to arrest the descent, and to cushion the helicopter on to the ground. Maintain the heading with pedals, and do not lower the collective until after all forward motion has ceased. You must also maintain the cyclic in a neutral, or slightly forward, position to preclude the development of a rocking motion if running on. Once you have come to a stop, lower collective fully, neutralize the pedals, and carry out a check of the instruments prior to increasing throttle in preparation for the takeoff.
POWER RECOVERY
As previously discussed, there may be occasions when it will not be prudent to conduct full-on autorotations, but you may wish to practice the techniques by performing an autorotational descent to a power recovery.
Enter autorotation as for a full-on, then, at a safe height, increase the throttle to rejoin the needles and bring the RPM into the correct operating range. This increase in power will cause the helicopter to yaw, anticipate this and apply pedal to prevent it. Initiate the flare at the appropriate height just as you did for the full-on autorotation. Maintain the heading with pedals and the flared attitude with cyclic; at the appropriate height, level the helicopter. Collective pitch must now be increased to check any tendency to sink and to achieve a steady hover, or hover- taxi, as the case may be. Throughout the manoeuvre prevent yaw with pedals. You may now carry out a normal transition to a climb. It is important that your throttle and collective movements be smooth and coordinated as it is possible to exceed Engine and/or Rotor limitations during this manoeuvre. Prior to moving on to the next exercise, or manoeuvre, ensure that you complete a check of the engine instruments.
EXERCISE 14 - EMERGENCIES
While modern helicopters are extremely reliable, emergencies requiring prompt pilot action occasionally do occur. Therefore, pilots must have a thorough understanding of the helicopter systems, and must repeatedly practice the handling of in-flight emergencies under simulated conditions, so that they are prepared to successfully handle a real emergency should one occur.
In this air exercise your instructor will acquaint you with the particular emergency procedures as they apply to your type of helicopter. These may include:
1. engine fire during start;
2. engine fire in flight;
3. engine fire during shutdown;
4. hydraulic failure;
5. fuel control or governor failure;
6. engine failure in flight;
7. tail rotor control failure;
8. smoke in the cockpit; and
9. transmission malfunction.
There are also a number of caution advisory lights in most modern helicopters which, when illuminated, give the pilot warning of a malfunction. The pilot’s reaction will vary according to the type of helicopter and the particular malfunction, but should generally include a precautionary landing. Indeed it is prudent and shows good airmanship to make a precautionary landing whenever unusual instrument indications are noticed, or when vibrations, noises or control forces that are out of the ordinary occur. Even if the helicopter appears to be operating normally in all other respects, it makes good sense to land and investigate.
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