Dynamic Stability

Subtopic: Dutch Roll, Spiral & Roll Subsidence Modes

Which of the following statements is/are TRUE about the stability of an aircraft?

Subtopic: Dutch Roll, Spiral & Roll Subsidence Modes

The stagnation pressures at the inlet and exit of a subsonic intake are 100 kPa and 98 kPa, respectively. The pressure recovery of this intake will be ______ (accurate to two decimal places).

Subtopic: Short Period & Phugoid Longitudinal Modes

The roots obtained by solving the longitudinal characteristic equation of an airplane are given by $\lambda_{1,2} = -0.005 \pm 0.05i$ and $\lambda_{3,4} = -1.2 \pm 2.5i$. These two pairs of complex conjugate roots correspond respectively to:

Subtopic: Short Period & Phugoid Longitudinal Modes

The d amping ratio in phugoid motion for gliders is usually less compared to powered aircraft because

Subtopic: Short Period & Phugoid Longitudinal Modes

The pitch angle and the angle of attack for a fixed wing aircraft are equal during

Subtopic: Dutch Roll, Spiral & Roll Subsidence Modes

The Dutch roll motion of the aircraft is described by following relationship                       r 76 . 0 49 . 4 1 26 . 0 r  The undamped natural frequency (rad/s) and damping ratio for the Dutch roll motion in that order are:

Subtopic: Short Period & Phugoid Longitudinal Modes

Which one of the following modes of a stable aircraft has non-oscillatory response characteristics?

Subtopic: Short Period & Phugoid Longitudinal Modes

An aircraft is flying with inertial ground and wind speeds of = (100, 5, 5) m/s and w = (0, -5, -10) m/s, respectively, as expressed in the body frame. The corresponding sideslip angle (in degrees) is

Subtopic: Dutch Roll, Spiral & Roll Subsidence Modes

An aerospace system operating under standard sea level conditions is governed by Dynamic Stability (Dutch Roll, Spiral & Roll Subsidence Modes). Compute the required parameter in standard SI units (rounded off to the acceptable range).

Subtopic: Dutch Roll, Spiral & Roll Subsidence Modes

In most airplanes, the Dutch roll mode can be excited by applying

Subtopic: Short Period & Phugoid Longitudinal Modes

Which one of the following shows the CORRECT variation of stagnation temperature along the axis of an ideal ram jet engine?

Subtopic: Dutch Roll, Spiral & Roll Subsidence Modes

What is the radial component of the fluid's velocity at a radial location 0.5 m from the pipe axis?

Subtopic: Short Period & Phugoid Longitudinal Modes

If l. j and & are unis vectors along x, y and z, respectively, then al the point * = 5, y = 10 the unit vector in the direction of the steepest slope of the hill will be:

Subtopic: Short Period & Phugoid Longitudinal Modes

If v= 200 m/s then the wavelength of the phugoid oscillations, assuming 8 = 9.81 m/s*, is. approximately:

Subtopic: Dutch Roll, Spiral & Roll Subsidence Modes

There are no twin: what order were they born (oldest first'

Subtopic: Short Period & Phugoid Longitudinal Modes

Stagnation temperature increases.

Subtopic: Short Period & Phugoid Longitudinal Modes

The short period damped frequency is

Subtopic: Short Period & Phugoid Longitudinal Modes

P: Short period mode 1: Coupled roll-yaw oscillations Q: Wing rock 2: Angle of attack remains constant R: Phugoid mode 3: Roll oscillations S: Dutch roll 4: Speed remains constant

Subtopic: Dutch Roll, Spiral & Roll Subsidence Modes

MJ/kg, the fuel to air ratio is

Subtopic: Short Period & Phugoid Longitudinal Modes

Power (BP) at the above flight condition will be