First-order Nomoto response coefficients K (yaw-rate sensitivity) and T (yaw time constant) from zig-zag trial data. K/T characterises how responsive a ship is to rudder.
Formula
$$ T \dot{\psi} + \dot \psi = K \delta, \quad K = \frac{\dot\psi_\text{steady}}{\delta}, \quad T = t_{63%} $$
Symbol legend
| Symbol | Meaning | Unit | Source |
|---|---|---|---|
| $δ$ | Rudder angle | ° | rudder indicator |
| $\dot\psi$ | Yaw rate | °/s | gyro rate |
| $K$ | Yaw-rate gain | (°/s)/° | result |
| $T$ | Yaw time constant | s | result |
Sources
- Nomoto et al. - On the Steering Qualities of Ships (1957).