flight-mech 1.0.4

A package to compute the characteristics of an airplane using simple flight mechanics equations.

Flight Mechanics Calculator

License

This software has been developed by Paul Creusy and is shared under the MIT License.

Getting started

Installation

To install this software, please clone the repository and install the required Python libraries using the command:

pip install -r requirements.txt

Usage

This software includes a simple atmospheric model and a set of flight mechanics equations allowing to compute plane characteristics.

Please note that all equations and variables are defined in the international unit system.

The plane model allows to compute the following quantities:

• max glide ratio
• speed at specific angle of incidence and altitude
• drag
• lift
• thrust
• stall speed
• reference speed
• minimum descent gliding slope
• gliding speed
• maximum gliding time
• maximum gliding range
• authorized velocity interval at fixed thrust for flight at constant altitude
• thrust needed at fixed altitude and angle of incidence
• minimum thrust needed at fixed altitude
• speed at minimum thrust
• maximum flight altitude
• speed for maximum ascension speed
• ascension slope for a specific angle of incidence and altitude
• load factor in turn
• maximum range at fixed altitude
• maximum range at fixed speed
• endurance
• take off distance without friction
• take off distance with friction
• landing distance
• take off speed
• landing speed
• alpha and delta coefficient at a flight point

Additionally, the following graphs can be generated:

• polar graph
• thrust-speed graph
• power-speed graph

Some examples are provided in the examples folder (please note that they do not cover all the use cases) as well with a few plane models in the plane_database folder.

Here is an overview of what the software can compute:

# Load the plane
plane = Plane("cessna_172", "./plane_database")

# Compute the fmax and CL at fmax
print("C_L_f_max", plane.C_L_f_max)
print("fmax", plane.f_max)

>> C_L_f_max 0.7745966692414834
>> fmax 12.909944487358056

# Compute the speed interval at 8000 meters
plane.m_fuel = 136.26  # kg
plane.update_variables(True)
print("reference speed at 8000m [m.s-1]", plane.compute_reference_speed(8000))
print("speed interval at 8000m [m.s-1]",
      plane.compute_velocity_interval_for_fixed_thrust(8000))
print("stall speed at 8000m [m.s-1]",
      plane.compute_stall_speed(8000, C_L_max=1.5))

>> reference speed at 8000m [m.s-1] 56.214394963985406
>> speed interval at 8000m [m.s-1] (22.544275306567194, 140.17120347383343)
>> stall speed at 8000m [m.s-1] 41.80281924283373

# Compute the ascension speed and slope at sea level
plane.m_fuel = 0  # kg
plane.update_variables(True)
print("max ascension speed [m.s-1]", plane.compute_max_ascension_speed(z=0))
print("reference speed at 0m [m.s-1]", plane.compute_reference_speed(z=0))
print("max slope at 0m [%]", plane.compute_max_ascension_slope(z=0))

>> max ascension speed [m.s-1] 32.89763560421959
>> reference speed at 0m [m.s-1] 34.523934888646956
>> max slope at 0m [%] 0.5695896796157822