| \(\alpha\) |
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 |
