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.
Photograph by Bruce Dale. Bound by cliffs and cut by erosion, canyons are deep, narrow valleys in the Earth's crust that evoke superlatives and a sense of wonder.Layers of rock outline stories of regional geology like the table of contents to a scientific text.hotograph by Bruce Dale. Bound by cliffs and cut by erosion, canyons are deep, narrow valleys in the Earth's crust that evoke superlatives and a sense of wonder.