| Ath | = | Throttle plate open area |
| b | = | Wingspan |
| c | = | Length of mean aerodynamic chord |
| [C] | = | Direction cosine matrix representing aircraft orientation |
| Cij | = | Components of the direction cosine matrix |
| CD | = | Discharge coefficient of the engine throttle |
| CT | = | Propeller coefficient of thrust |
| CP | = | Propeller coefficient of power required |
| CX, CY, etc. | = | Nondimensional force and moment coefficients |
 |
= | Stability derivatives and/or polynomial coefficients |
| D | = | Propeller diameter |
| e0, e1, e2, e3 | = | Quarternions representing aircraft orientation |
| Ff | = | Forward friction force exerted on a landing gear tire |
| Fn | = | Ground normal force exerted on a landing gear tire |
| Fs | = | Sideward friction force exerted on a landing gear tire |
| (F/A) | = | Fuel to air mixture ratio |
| g | = | Acceleration of gravity
 ft/s |
| h | = | Altitude |
| h | = | Distance from the ground |
| Ip | = | Propeller polar moment of inertia |
| Ixx, Iyy, Izz | = | Aircraft moments of inertia |
| Ixy, Ixz, Iyz | = | Aircraft products of inertia |
| J | = | Propeller advance ratio |
| L, M, N | = | Components of the resultant moment on the airplane |
| m | = | Mass of the airplane |
| mf | = | Fuel mass |
 |
= | Mass flow rate past the throttle |
| M | = | Mach number |
| N | = | Propeller/engine angular speed, revolutions per second |
| p | = | Outside air pressure |
| pm | = | Manifold pressure |
| P | = | Power required by propeller |
| Pe | = | Excess power delivered to the propeller |
| p, q, r | = | Components of aircraft angular velocity |
 |
= | Nondimensional components of aircraft angular velocity |
| q | = | Dynamic pressure |
| Qp | = | Resultant torque on the propeller |
| r | = | Distance from the Earth's center |
| R | = | Gas constant of the air
 (ft lb)/(slug
 R) |
| S | = | Wing planform area |
| T | = | Thrust force |
| T | = | Outside air temperature |
| Tm | = | Manifold temperature |
| u, v, w | = | Components of aircraft velocity |
| ua, va, wa | = | Wind-relative components of aircraft velocity |
| ug, vg, wg | = | Components of the velocity of a landing gear tire |
| V | = | Airspeed |
| Vk | = | Threshold velocity for static friction |
| Vd | = | Total displacement of the engine |
| Vm | = | Volume of the intake manifold |
| X, Y, Z | = | Components of the resultant force on the aircraft |
| x, y, z | = | Coordinates in a Cartesian coordinate system |
| xc, yc, zc | = | Coordinates of the aircraft's CG |
| xg, yg, zg | = | Coordinates of the bottom of an extended landing gear tire |
| xs | = | Distance of the screen from user's eyes |
| zp | = | Body z-coordinate of the propeller shaft |
 |
= | Angle of attack |
 |
= | Angle of sideslip |
|
= | Compressibility correction factor |
 |
= | Specific heat ratio of the air
 |
 |
= | Differential aileron deflection |
 |
= | Percent of full brake pressure applied |
 |
= | Elevator deflection |
 |
= | Flap deflection |
 |
= | Leading-edge flap deflection |
 |
= | Rudder deflection |
 |
= | Propeller efficiency |
 |
= | Volumetric efficiency of the engine |
 |
= | Pitch Euler angle |
 |
= | Longitude |
 |
= | Static and kinematic coefficients of friction of tires |
 |
= | Outside air density |
 |
= | Roll Euler angle |
 |
= | Geodetic latitude |
 |
= | Geocentric latitude |
 |
= | Yaw Euler angle |