RCAIDE.Library.Mission.Segments.Ground.Takeoff

Takeoff#

Functions

initialize_conditions(segment)

Initializes conditions for aircraft takeoff ground roll

initialize_conditions(segment)[source]#

Initializes conditions for aircraft takeoff ground roll

Parameters:

segment (Segment) –

The mission segment being analyzed
  • altitudefloat

    Ground altitude [m]

  • velocity_startfloat

    Initial ground speed [m/s]

  • velocity_endfloat

    Rotation speed [m/s]

  • ground_inclinefloat

    Runway incline angle [rad]

  • friction_coefficientfloat

    Ground friction coefficient [-]

  • state:
    numerics:
    dimensionless:
    control_pointsarray

    Discretization points [-]

    conditionsData

    State conditions container

    unknowns:
    ground_velocityarray

    Ground velocity profile [m/s]

    initialsData, optional

    Initial conditions from previous segment

  • analyses:
    weights:
    vehicle:
    mass_properties:
    takeofffloat

    Aircraft takeoff mass [kg]

Returns:

Updates segment conditions directly:
  • conditions.frames.inertial.velocity_vector [m/s]

  • conditions.ground.incline [rad]

  • conditions.ground.friction_coefficient [-]

  • conditions.freestream.altitude [m]

  • conditions.frames.inertial.position_vector [m]

  • conditions.weights.total_mass [kg]

Return type:

None

Notes

This function sets up the initial conditions for a ground takeoff segment with acceleration from initial speed to rotation speed. The segment handles ground effects, friction, and incline during the takeoff roll.

Calculation Process
  1. Check initial conditions

  2. Initialize velocity profile:
    v = v0 + (vf - v0)*t where:
    • v0 is initial speed

    • vf is rotation speed

    • t is normalized time/distance

  3. Set ground conditions:
    • Friction coefficient

    • Ground incline

  4. Set position and altitude

  5. Set aircraft mass

Major Assumptions
  • Constant friction coefficient

  • Constant ground incline

  • Linear velocity increase

  • Quasi-steady acceleration

  • Small minimum velocity for numerical stability