RCAIDE.Library.Mission.Segments.Transition.Constant_Acceleration_Constant_Pitchrate_Constant_Altitude

Constant_Acceleration_Constant_Pitchrate_Constant_Altitude

Functions

initialize_conditions(segment)

Initializes conditions for transition segment with constant acceleration and pitch rate

initialize_conditions(segment)

Initializes conditions for transition segment with constant acceleration and pitch rate

Parameters:

segment (Segment) –

The mission segment being analyzed

• altitudefloat

  Fixed flight altitude [m]

• air_speed_startfloat

  Initial true airspeed [m/s]

• air_speed_endfloat

  Final true airspeed [m/s]

• accelerationfloat

  Constant acceleration [m/s^2]

• sideslip_anglefloat

  Aircraft sideslip angle [rad]

• pitch_initialfloat

  Initial pitch angle [rad]

• pitch_finalfloat

  Final pitch angle [rad]

• state:

  numerics:

  dimensionless:

  control_pointsarray

  Discretization points [-]

  conditionsData

  State conditions container

  initialsData, optional

  Initial conditions from previous segment

Returns:

Updates segment conditions directly:

• conditions.freestream.altitude [m]

• conditions.frames.inertial.position_vector [m]

• conditions.frames.inertial.velocity_vector [m/s]

• conditions.frames.body.inertial_rotations [rad]

• conditions.frames.inertial.time [s]

Return type:

None

Notes

This function sets up the initial conditions for a transition segment with constant acceleration and pitch rate at fixed altitude. The segment handles transitions between different flight phases while maintaining altitude.

Calculation Process

1. Check initial conditions

2. Calculate time required based on acceleration:

   t = (Vf - V0)/ax where:

   • V0 is initial airspeed

   • Vf is final airspeed

   • ax is acceleration

3. Calculate velocity magnitude profile: V = V0 + ax*t 4. Decompose velocity using sideslip:

• v_x = V*cos(β)

• v_y = V*sin(β)

where β is sideslip angle 5. Linear pitch transition:

θ = θ0 + (θf - θ0)*t/tf for θf > θ0 θ = θ0 - (θ0 - θf)*t/tf for θf < θ0

Major Assumptions

• Constant acceleration

• Constant pitch rate

• Fixed altitude

• Linear pitch variation

• Coordinated flight

• Small angle approximations

See also

RCAIDE.Framework.Mission.Segments