oldfart
Elite Veteran
Location: Vancouver, Canada
| Just a caution here, as I find many newbies do not understand the difference between the two systems.
The STANDARD auto-rotation system that is on the Hawk, is the same system we have used since I started flying helis in 1985. With this system you can easily auto, as long as you keep flying forward. In an auto there is no engine torque to compensate for (as the engine is disengaged) so the vertical tail fin will make the heli weather-vane in the direction of flight. We have been doing autos with this system that consist of 180 degree and 360 degree turns for many, many years.
As this system does not have to drive the tail rotor, it does not take as much kinetic energy from the rotor, leaving more for the landing. If one does want a bit of steering (e.g. to help keep the nose from yawing a bit at the bottom, when there is no forward speed) then all one can do is up the throttle a bit in throttle hold. Use just enough to engage the clutch so that it causes the tail rotor to turn slowly, but not enough to cause the one-way auto-bearing to turn the maingear faster then the speed of the mainrotor. As long as the motor is turning the maingear at a slower speed then the rotor energy is turning the rotor, the one-way auto bearing will not try to turn the rotor, so you will still be auto-rotating.
For a person, learning to autorotate, this IMHO, is a better system then the Constant Tail Drive system.
What the CTD system allows one to do, once he is adequately proficient at autos, is to fly his autos backwards, to do pirouettes on his way down and to go inverted etc during the auto. But all of these auto maneuvers that require the tail to be driven, will take energy from the main rotor. So one will have to be proficient enough to have learned how to rebuild any rotor speeds lost through different parts of these maneuvers.
Also, CTD driven systems are much less forgiving of a hard auto landing, as the tail rotor is being driven at a high speed (4.5 to 5 times that of the main rotor)if the tail rotor touches the ground during the hard landing, the energy has to be dissipated. This energy will be dissipated by stripping gears, stretching belts or damaging other components in the tail drive train.
In conclusion, unless you want to move up into doing aerobatic, 3D type of autos, you are better with the standard system. As the Hawk was designed to be an entry level heli, I think it is best that it uses the standard system. |
