Flight Mech Exam 3

Longitudinal

Movement in the x-direction, movement in z-direction, and rotation about the y-axis are involved in the _____________ (longitudinal/lateral) equations of motion.

Lateral

Movement in the y-direction, rotation about the x-axis, and rotation about the z-axis are involved in the _____________ (longitudinal/lateral) equations of motion.

Static Stability

The inertial tendency of an object to develop forces or moments that return it to a steady-state condition following some perturbation.

Static Stability

The inertial tendency of an object to return to trim condition.

Dynamic Stability

The time history of vehicle motion after the initial tendency to return to equilibrium. For instance, does the object oscillate as it asymptotically approaches some finite limit?

Dynamically

An object is considered ____________ (statically/dynamically) stable if, of its own accord, it eventually returns to and remains at an equilibrium position over a period of time.

Neutral Point

The point coinciding with the aircraft’s aerodynamic center (AC). It is given this name because neither variation in AoA nor changes to the forces acting at this point affect/help correct for perturbations. This is because forces acting at this point do not create moments.

Longitudinal Static Stability

The main requirement for _____________ is that c_m,α < 0