public static void Calculate_WithAirspeedEqualToThresholdAndNoNormalForcePresent_ReturnsExpectedFlightPathAngleRate(AircraftData aircraftData)
{
// Setup
const double heightThreshold = 0.01;
var random = new Random(21);
var aircraftState = new AircraftState(aircraftData.MaximumPitchAngle,
random.NextAngle(),
100,
heightThreshold - random.NextDouble(),
random.NextDouble());
Angle angleOfAttack = aircraftState.PitchAngle - aircraftState.FlightPathAngle;
// Precondition
double lift = AerodynamicsHelper.CalculateLift(aircraftData.AerodynamicsData,
angleOfAttack,
airDensity,
aircraftState.TrueAirspeed);
double takeOffWeightNewton = aircraftData.TakeOffWeight * 1000; // N
Assert.IsTrue(lift > takeOffWeightNewton);
var calculator = new TestTakeOffDynamicsCalculator(aircraftData, airDensity, gravitationalAcceleration);
// Call
AircraftAccelerations accelerations = calculator.Calculate(aircraftState);
// Assert
double expectedRate = (gravitationalAcceleration * (lift - takeOffWeightNewton))
/ (takeOffWeightNewton * aircraftState.TrueAirspeed);
Assert.AreEqual(expectedRate, accelerations.FlightPathRate.Radians, tolerance);
}
public void GivenAircraftStateResultsIntoInvalidCalculationException_WhenCalculateCalled_ThenCalculatorExceptionThrown()
{
// Given
var random = new Random(21);
AircraftData aircraftData = AircraftDataTestFactory.CreateRandomAircraftData();
var calculator = new TestTakeOffDynamicsCalculator(aircraftData, random.NextDouble(), random.NextDouble());
var state = new AircraftState(aircraftData.AerodynamicsData.ZeroLiftAngleOfAttack - Angle.FromRadians(1),
new Angle(),
random.NextDouble(),
random.NextDouble(),
random.NextDouble());
// When
TestDelegate call = () => calculator.Calculate(state);
// Then
var exception = Assert.Throws <CalculatorException>(call);
Exception innerException = exception.InnerException;
Assert.IsInstanceOf <InvalidCalculationException>(innerException);
Assert.AreEqual(innerException.Message, exception.Message);
}
public void Calculate_AircraftStateNull_ThrowsArgumentNullException()
{
// Setup
var random = new Random(21);
AircraftData aircraftData = AircraftDataTestFactory.CreateRandomAircraftData();
var calculator = new TestTakeOffDynamicsCalculator(aircraftData, random.NextDouble(), random.NextDouble());
// Call
TestDelegate call = () => calculator.Calculate(null);
// Assert
var exception = Assert.Throws <ArgumentNullException>(call);
Assert.AreEqual("aircraftState", exception.ParamName);
}
public static void Calculate_WithAircraftStateHeightSmallerThanThresholdAndLiftSmallerThanTakeOffWeight_ReturnsExpectedTrueAirspeedRate(AircraftData aircraftData)
{
// Setup
const double airspeed = 10.0;
const double threshold = 0.01;
var random = new Random(21);
var aircraftState = new AircraftState(aircraftData.MaximumPitchAngle,
random.NextAngle(),
airspeed,
threshold - random.NextDouble(),
random.NextDouble());
Angle angleOfAttack = aircraftState.PitchAngle - aircraftState.FlightPathAngle;
// Precondition
double lift = AerodynamicsHelper.CalculateLift(aircraftData.AerodynamicsData,
angleOfAttack,
airDensity,
airspeed);
double takeOffWeightNewton = aircraftData.TakeOffWeight * 1000; // N
Assert.IsTrue(lift < takeOffWeightNewton);
double thrust = random.NextDouble() * 1000;
double drag = random.NextDouble() * 100;
double frictionCoefficient = random.NextDouble();
var calculator = new TestTakeOffDynamicsCalculator(aircraftData, airDensity, gravitationalAcceleration)
{
Thrust = thrust,
Drag = drag,
RollDrag = frictionCoefficient
};
// Call
AircraftAccelerations accelerations = calculator.Calculate(aircraftState);
// Assert
double horizontalWeightComponent = takeOffWeightNewton * Math.Sin(aircraftState.FlightPathAngle.Radians);
double groundDrag = frictionCoefficient * (aircraftData.TakeOffWeight * 1000 - lift);
double expectedAcceleration = (gravitationalAcceleration * (thrust - drag - groundDrag - horizontalWeightComponent))
/ takeOffWeightNewton;
Assert.AreEqual(expectedAcceleration, accelerations.TrueAirSpeedRate, tolerance);
}
public static void Calculate_WithAircraftStateSpeedHigherThanRotationSpeedAndPitchAngleAtMaximumPitch_ReturnsExpectedZeroPitchRate(AircraftData aircraftData)
{
// Setup
double rotationSpeed = GetRotationSpeed(aircraftData);
var random = new Random(21);
var aircraftState = new AircraftState(aircraftData.MaximumPitchAngle,
random.NextAngle(),
rotationSpeed + random.NextDouble(),
random.NextDouble(),
random.NextDouble());
var calculator = new TestTakeOffDynamicsCalculator(aircraftData, airDensity, random.NextDouble());
// Call
AircraftAccelerations accelerations = calculator.Calculate(aircraftState);
// Assert
Assert.Zero(accelerations.PitchRate.Degrees);
}
public static void Calculate_Always_SendsCorrectInput()
{
// Setup
var random = new Random(21);
AircraftData aircraftData = AircraftDataTestFactory.CreateRandomAircraftData();
var calculator = new TestTakeOffDynamicsCalculator(aircraftData, random.NextDouble(), random.NextDouble());
Angle angleOfAttack = AerodynamicsDataTestHelper.GetValidAngleOfAttack(aircraftData.AerodynamicsData);
var state = new AircraftState(angleOfAttack,
new Angle(),
random.NextDouble(),
random.NextDouble(),
random.NextDouble());
// Call
calculator.Calculate(state);
// Assert
Assert.AreSame(state, calculator.CalculateDragInput);
}
public static void Calculate_WithAircraftStateAlways_ReturnsExpectedClimbRate()
{
// Setup
var random = new Random(21);
AircraftData aircraftData = AircraftDataTestFactory.CreateRandomAircraftData();
Angle angleOfAttack = AerodynamicsDataTestHelper.GetValidAngleOfAttack(aircraftData.AerodynamicsData);
var aircraftState = new AircraftState(angleOfAttack,
new Angle(),
random.NextDouble(),
random.NextDouble(),
random.NextDouble());
var calculator = new TestTakeOffDynamicsCalculator(aircraftData, random.NextDouble(), random.NextDouble());
// Call
AircraftAccelerations accelerations = calculator.Calculate(aircraftState);
// Assert
double expectedClimbRate = aircraftState.TrueAirspeed * Math.Sin(aircraftState.FlightPathAngle.Radians);
Assert.AreEqual(expectedClimbRate, accelerations.ClimbRate, tolerance);
}
public void Calculate_WithAircraftStateAndSpeedHigherThanRotationSpeedAndPitch_ReturnsExpectedPitchRate(AircraftData aircraftData)
{
// Setup
var random = new Random(21);
double rotationSpeed = GetRotationSpeed(aircraftData);
double pitchAngle = aircraftData.MaximumPitchAngle.Degrees - random.NextDouble();
var aircraftState = new AircraftState(Angle.FromDegrees(pitchAngle),
random.NextAngle(),
rotationSpeed + random.NextDouble(),
random.NextDouble(),
random.NextDouble());
var calculator = new TestTakeOffDynamicsCalculator(aircraftData, airDensity, random.NextDouble());
// Call
AircraftAccelerations accelerations = calculator.Calculate(aircraftState);
// Assert
Angle expectedPitchRate = aircraftData.PitchAngleGradient;
Assert.AreEqual(expectedPitchRate, accelerations.PitchRate);
}
public static void Calculate_WithAirspeedLowerThanThreshold_ReturnsExpectedZeroRate()
{
// Setup
var random = new Random(21);
AircraftData aircraftData = AircraftDataTestFactory.CreateRandomAircraftData();
Angle angleOfAttack = AerodynamicsDataTestHelper.GetValidAngleOfAttack(aircraftData.AerodynamicsData);
var aircraftState = new AircraftState(angleOfAttack,
new Angle(),
random.NextDouble(),
random.NextDouble(),
random.NextDouble());
// Precondition
Assert.IsTrue(aircraftState.TrueAirspeed < 1);
var calculator = new TestTakeOffDynamicsCalculator(aircraftData, random.NextDouble(), random.NextDouble());
// Call
AircraftAccelerations accelerations = calculator.Calculate(aircraftState);
// Assert
Assert.Zero(accelerations.FlightPathRate.Degrees);
}