landing-gear mounting points, giving it a slightly nose-down attitude on the ground and better matching of the skids to the ground in a low-altitude hover with two people on board. The R22 Beta added an engine speed governor (optional), rotor brake, and auxiliary fuel tank (optional). The battery was moved from below the instrument cluster to the engine compartment for better balance. The R22 has been offered as an instrument trainer version, with optional fixed floats as the R22 Mariner, and other special configurations for police work, electronic news gathering, and so on. The R22 Beta II received a larger Lycoming O-360 engine derated for sea-level operation. It allows greater altitudes for hovering in and out of ground effect (HIGE/HOGE). The R22 Beta II also made the engine speed governor standard and included a carburetor heat assist, which correlates adding carburetor heat with a decrease in collective control. Only the basic skid style is currently being sold. Controls Instead of floor-mounted cyclic sticks between the pilot's knees, the R22 uses a unique teetering "T-Bar" control connected to a stick that emerges from the console between the seats. This makes it easier for occupants to enter and exit the cabin and reduces chances for injury in the event of a hard landing. The teetering bar has a hand grip on both sides that hangs down between the pilots' legs. Thus, if teetered to the right, the right-side pilot would be flying and the left grip would be about 12 inches above the left pilot's lap. R22 flight instructors quickly learn how to fly with their hand in the air. The left part of the bar, left collective control, and left tail-rotor pedals can be removed if the left-seat occupant is not certified to fly the R22 or if the space is needed for technical or observer duties. A floor-mounted, foot-activated push-to-talk switch facilitates intercom communications for the left-seat occupant, although some later models may be equipped with a voice-activated intercom system. The helicopter rotor system consists of a two-bladed main rotor and two-bladed antitorque rotor on the tail, each equipped with a teetering hinge. The main rotor is also equipped with two coning hinges. Collective and cyclic pitch inputs to the main rotor are transmitted through pushrods and a conventional swashplate mechanism. Control inputs to the preconed tail rotor are transmitted through a single pushrod inside the aluminum tail cone. To