\(\alpha\) |
angle of attack of the fuselage, rotor plane or a blade section depending on the context |

A |
rotor area |

AFCS |
automatic flight control system |

\(\beta\) |
sideslip angle or blade flapping angle |

\(\beta_C\) |
main rotor longitudinal flapping |

\(\beta_S\) |
main rotor lateral flapping |

\(C_L\) |
roll moment coefficient (\(L/\rho AR(\Omega R)^2\)) |

\(C_M\) |
pitch moment coefficient (\(M/\rho A R(\Omega R)^2\)) |

\(C_T\) |
rotor thrust coefficient (\(T/\rho A (\Omega R)^2\)) |

CCW |
counterclockwise |

CW |
clockwise |

D |
drag force |

F |
force |

GW |
gross weight |

\(\lambda\) |
rotor inflow ratio ((\(V\sin \alpha + v)/\Omega R\)) |

L |
lift force or roll moment, depending on context |

LZ |
landing zone |

\(\mu\) |
rotor advance ratio (\(V\cos \alpha /\Omega R\)) |

\(m\) |
mass |

M |
pitch moment |

N |
yaw moment |

NR |
main rotor speed as a percent of nominal speed |

\(\Omega\) |
main rotor speed |

\(\phi\) |
Euler roll angle |

\(\psi\) |
Euler yaw angle |

\(\Psi\) |
main rotor azimuth angle |

\(p\) |
body roll rate |

\(q\) |
body pitch rate |

\(r\) |
body yaw rate |

\(Q_{mp}\) |
torque provided to main rotor |

\(Q_p\) |
total torque output by engine shaft |

\(\rho\) |
air density |

\(r\) |
distance of blade section from rotor center |

R |
main rotor radius |

SAS |
stability augmentation system |

T |
rotor thrust |

TAS |
true airspeed |

\(\theta\) |
Euler pitch angle |

\(\theta_0\) |
collective control angle |

\(\theta_C\) |
lateral cyclic blade angle |

\(\theta_S\) |
longitudinal cyclic blade angle |

\(u\) |
body axis forward velocity |

\(v\) |
body axis lateral velocity |

\(V\) |
total velocity of air relative to helicopter or rotor |

\(v_i\) |
rotor-induced velocity |

\(w\) |
body axis vertical velocity |

\(y\) |
out-of-plane displacement of a blade section |