HOTAS is an acronym for the aviation concept Hands On Throttle And Stick. This concept involves placing as many of the frequently used or associated controls on the throttle lever and control column of an aircraft. This placement allows for peripheral control activation without the pilot having to remove hands from the throttle and control column or side stick. It also allows for these actions to be carried out without the pilot having to break visual contact with the windshield quadrant. This makes a significant difference to ease of operation during high load or stress phases of flight such as target tracking, landings, in-flight refueling, or holding formation.
Carrying out complex and pressured flight maneuvers requires high levels of concentration and a constant series of power, pitch, and roll control inputs. That being said, the HOTAS concept makes a lot of sense as it keeps both the pilot's hands and visual focus where they should be — on the task at hand. The placement of additional controls on throttle levers and joy sticks is by no means a new practice; gun actuators were placed on the control columns of fighters in both World Wars. New generation aircraft have, however, made a art form of HOTAS with ergonomically formed controls bristling with auxiliary switches and buttons.
Although the multifunction side stick and throttle levers of an F-16 Falcon or MiG-29 fighter are a far cry from the simple hat switch equipped joy sticks on the Spitfires or Mustangs of years past, the principle remains the same. Auxiliary controls are placed on control columns which are typically used during controlled flight and ideally which are related to the parent control. For instance, commercial jet airliners feature at least a mike key, autopilot disconnect, and trim switches on each pilot's yoke because these functions are often activated during manual flight phases. Modern jet fighters usually have thrust related auxiliary controls mounted on the thrust lever. Auto throttle activation and reverse thrust levers are also located on the throttle quadrants of commercial jets.
The HOTAS concept is not restricted to aircraft either; many other vehicle controls lean towards multitasking. A peek into the cockpit of a Formula One race car reveals an impressive array of paddles and button on the steering wheel. Just as is the case in a jet fighter, this functionality allows the drivers to change gears without having to take their hands, or eyes, off the wheel and road ahead. HOTAS has also found its way into the average family vehicle as well; the sound system, trip computer, and cruise control buttons appear on the steering wheels of many newer cars.