India two four,
The nasties with the old gimbal head were caused by dynamic instability due to the design of the head. Any gust-induced pitch excursions were dynamically unstable i.e. a positive gust lead to a pitch up with no corrective damping. this was exacerbated by little pitch reference due to no bodywork in front of you. In consequence pitch diversions could be picked up late and over-controlled leading to PIO and a divergent phugoid followed by a push over into negative G. This was a killer. The push-over still is a killer but the modern gyros have a horizontal tailplane of sufficient volume to damp out pitch oscillations, the head has an offset pitch hinge balanced by a spring which has a self-correcting couple and there is a normal fuselage to give better pitch reference. The old style gyros
can be flown but they need careful handling.
Crab,
The TO technique is to pre-rotate the rotor to 200 rrpm on the wheel brakes, release brakes, stick fully back and full power. As speed builds the nose will rise; keep the nosewheel
just off the ground and let the speed continue to rise. Forward stick needs to be fed in to maintain what is called wheel balancing. As the speed rises the gyro will fly itself off with rising rrpm, there is no positive rotation needed, the gyro flies in its own time. Rotor drag is certainly a problem on take off. A more back-tilted rotor will speed rrpm rise but quickly the drag will overcome power available and TO will not occur. Wheel balancing is the best compromise between rotor angle of attack and rotor drag. As for landing, the modern gyros have sufficient vertical tail volume to maintain rudder authority down to the point when the nosewheel touches. I have never run out of rudder authority in over 400 hrs.
As with any a/c competent training to learn the correct handling techniques is essential. There was an idea in the past that gyros were so easy to fly that you could teach yourself, this lead to accidents and fatalities.
ShyTorque,
See my comments re difference between old and modern gyros.
CJ and RINKER,
The cause is not yet known,
AFAIK, so please do not jump to conclusions.
As to the Cavalon itself, it is a nice stable cruising machine. 560 kg AUW, about 300 kg empty, tanks for 5 hrs and a c100 mph cruise. As usual load has to be split between fuel and pax.
Dick.