RCAIDE.Library.Mission.Segments.Descent.Linear_Speed_Constant_Rate

Linear_Speed_Constant_Rate

Functions

initialize_conditions(segment)

Initializes conditions for linear speed descent at fixed rate

initialize_conditions(segment)

Initializes conditions for linear speed descent at fixed rate

Parameters:

segment (Segment) –

The mission segment being analyzed

• descent_ratefloat

  Rate of descent [m/s]

• air_speed_startfloat

  Initial true airspeed [m/s]

• air_speed_endfloat

  Final true airspeed [m/s]

• altitude_startfloat

  Initial altitude [m]

• altitude_endfloat

  Final altitude [m]

• sideslip_anglefloat

  Aircraft sideslip angle [rad]

• state:

  numerics.dimensionless.control_pointsarray

  Discretization points [-]

  conditionsData

  State conditions container

  initialsData, optional

  Initial conditions from previous segment

Return type:

None

Notes

This function sets up the initial conditions for a descent segment with linearly varying true airspeed and constant descent rate. The horizontal velocity components vary with the changing airspeed. Updates segment with velocity vector, altitude, and position vector.

Calculation Process

1. Discretize altitude profile

2. Calculate true airspeed variation: V = V0 + (Vf - V0)*t where:

• V0 is initial airspeed

• Vf is final airspeed

• t is normalized time/distance

3. Calculate horizontal velocity magnitude: v_xy = sqrt(V^2 - v_z^2) where:

• V is local true airspeed

• v_z is descent rate

4. Decompose horizontal velocity using sideslip angle:

   • v_x = v_xy * cos(β)

   • v_y = v_xy * sin(β)

   where β is sideslip angle

Major Assumptions

• Linear true airspeed variation

• Constant descent rate

• Small angle approximations

• Quasi-steady flight

• No wind effects

See also

RCAIDE.Framework.Mission.Segments