Unrealistic thrust asked in the breguet cruise segment

[esnguyenvan]

In class BreguetCruiseSegment() the variable reference_area is assigned a default value of 1.0 and should only be used is use_max_lift_drag_ratio is set to False:

class BreguetCruiseSegment(CruiseSegment, mission_file_keyword="breguet"):
    """
    Class for computing cruise flight segment at constant altitude using Breguet-Leduc formula.
    As formula relies on SFC, the :attr:`propulsion` model must be able to fill FlightPoint.sfc
    when FlightPoint.thrust is provided.
    """

    #: if True, max lift/drag ratio will be used instead of the one computed with polar using
    #: CL deduced from mass and altitude.
    #: In this case, reference_area parameter will be unused
    use_max_lift_drag_ratio: bool = False

    #: The reference area, in m**2. Used only if use_max_lift_drag_ratio is False.
    reference_area: float = 1.0

    #:
    climb_and_descent_distance: float = 0.0

    def __post_init__(self):
        super().__post_init__()
        self.target.ground_distance = self.target.ground_distance - self.climb_and_descent_distance

    def compute_from(self, start: FlightPoint) -> pd.DataFrame:
        self.complete_flight_point(start)

        cruise_mass_ratio = self._compute_cruise_mass_ratio(start, self.target.ground_distance)

However use_max_lift_drag_ratio is not checked before calling complete_flight_point() in function compute_from(), where the variable reference_area is used with its default value of 1.0 to compute the lift and drag which in turn asks for some rocket thrust of 1 million Newtons to the engine module.

I suggest additional checks or merging of function _compute_cruise_mass_ratio() into compute_from(), unless we'd like to launch FAST-OAD into space exploration :).