The present invention relates to a
bellcrank (40) for a flight-attitude-changing linkage (27, 25A, 28A) of the variable
gain type. The linkage (27, 25A, 28A) connects a manual flight control device of a
rotary wing aircraft (1), e.g. a
hybrid helicopter, to at least one airfoil of said aircraft (1) suitable for causing a change in flight attitude. Said
bellcrank (40) includes first and second sliders (50, 52). Said first slider (50) is connected to a movable portion (57, 61) of a
setpoint flight-attitude-changing linkage (24) that delivers a
setpoint, with movements of said linkage causing the
gain of said variable-
gain linkage (27, 25A, 28A) to be adjusted, which gain is proportional to the position of said movable portion (57, 61).