Lire http://www.flightsafetyaustralia.com/2015/09/flexi-legs-a-new-angle-on-helicopter-landing-gear/
Helicopters and slopes do not go well together. Blade strike is one unpleasant possibility and ground resonance—where the rotor develops severe vibration—is another hazard.
[youtube https://www.youtube.com/watch?v=Ip_WqX8nmKY&w=560&h=315]