# Aircraft Base Physics Analysis

”’The following Python code is intended to analyze an aircraft on the simplest possible physical basis. Please comment on any errors in formulation or approach. ”’

PropulsionEfficiency = 0.9 # Efficiency of propulsion system

PropulsionEffectiveness = 20 # N/kW

EnergyGravimetricDensity= 205 # Wh/kg

VehicleEfficiency = 20 # L/D = CL/CD

# in steady level flight:
# L = W , D = T
# therefore
# L/D = W/T
# therefore
# T = W*D/L = W*(1/LOD)
# W = T*L/D = T*(1*LOD)

Battery_WH = 500*1000
Battery_Mass = Battery_WH/EnergyGravimetricDensity # Wh / (Wh/kg) = kg
Battery_Mass_frac = 0.5
Empty_Mass = Battery_Mass/Battery_Mass_frac # kg
Aircraft_Mass = Empty_Mass + Battery_Mass # kg
Weight = Aircraft_Mass*9.81 # kg -> N

Thrust = Weight*(1/VehicleEfficiency) # N * ( N/N ) = N

print(Thrust,’N thrust’)
print(Weight,’N weight’)
print(Aircraft_Mass,’kg mass’)
print(Thrust/Weight,’TWR’)

PropPower =Thrust/(PropulsionEffectiveness/1000) # N/(N/W) = W
PropPower +=(PropPower*(1-PropulsionEfficiency)) # W + W = W

print(PropPower,’W power’)

PropEndurance=Battery_WH/(PropPower)

print(PropEndurance,’hrs endurance’)