Patent ID: 9272778
Filing Date: 2016-03-01
CPC Classification: B64C,B64D

Claim Text:
1. A piloting assistance device for a hybrid helicopter having a rotary wing including a main rotor, first and second half-wings respectively with first and second propellers, and an engine installation having at least one turbine engine continuously driving the rotary wing and the propellers by meshing with a mechanical interconnection system, the piloting assistance device comprising: at least one pitch sensor configured to measure a current mean pitch of blades of the propellers in real time; an air speed sensor configured to measure true air speed of the hybrid helicopter; a speed of rotation sensor configured to measure speed of rotation of the propellers; a density sensor configured to measure density of air in the vicinity of the hybrid helicopter; a computer provided with a memory containing a first equation determining a power gradient as a function of the current mean pitch, the computer being connected to the sensors and being configured to receive first and second power values from a regulator member of the engine installation, the first and second power values relating respectively to a maximum power capable of being delivered by the engine installation and to a power currently being delivered by the engine installation, the computer being further configured to determine a maximum mean pitch to be complied with for the blades of the propellers without exceeding power available for the propellers, the computer determining the maximum mean pitch as a function of the current mean pitch, the first and second power values, and the power gradient; a display configured to present the maximum mean pitch on a display screen; and an autopilot device configured to operate in an autopilot mode for controlling flight of the hybrid helicopter, wherein while operating in the autopilot mode the autopilot device controls the driving of the rotary wing and the propellers by the least one turbine engine such that the current mean pitch does not exceed the maximum mean pitch.