I would never argue with the estimable 237SJ, except to say a helicopter can glide down… but… big but… the radius of landing sites is quite small. Additionally, the helicopter can "glide" down only if the main rotor is intact and still revolving. Helicopter pilots practice the maneuver incessantly in training and after…it's called autorotation… the steep descent is required to keep air pushing through the main rotor to keep it (the main rotor) up to speed so at the very last seconds before contacting the earth the "collective" control is pulled up to slow the descent and make a landing.
I'll take a Boeing 727 any time...