Fifty Years of Innovation in Performance Limit Indicator (A success story of Airbus Helicopters contribution, to helicopter fleet safety , by simplifying piloting and reducing workload)

Since their invention, helicopters were typical flying object that requested very specific competencies to control their flight. The control of the rotors power, delivered by the engine, was subject to multiple indicators that were installed in the cockpit. Depending on the various technologies, engine temperature, turbine rotation speed, and torque are measured; main gearbox torque, or free turbine speed are monitored. The pilot has the responsibility to ensure that none of them are at their limit, depending on the environmental conditions mainly outside temperature and atmospheric pressure.