HELI-90/120/140 refers to a helicopter, with the servos orientated at 90 degrees (2 servos, generally beginner helicopters with forward, back, right, and left movement on the cyclic stick), 120 degrees (3 servos- generally for more advanced helicopters that have collective pitch controls on the rotor blades (yes, this means inverted flight too)), ...
canyon. n. 1. (Physical Geography) a gorge or ravine, esp in North America, usually formed by the down-cutting of a river in a dry area where there is insufficient rainfall to erode the sides of the valley.
Zhemchug Canyon is the largest submarine canyon in the world, based on drainage area (11,350 km2) and volume (5800 km3). Deep, cold, oxygen-rich waters well up from the deeps into the canyon, providing sustenance to an enormous array and variety of life forms.