# This file is part of FAST-OAD_CS23-HE : A framework for rapid Overall Aircraft Design of Hybrid
# Electric Aircraft.
# Copyright (C) 2025 ISAE-SUPAERO
import numpy as np
import openmdao.api as om
[docs]
class LCCManufacturingCost(om.ExplicitComponent):
"""
Computation of the manufacturing labor cost for the airframe as obtained from
:cite:`gudmundsson:2013`. Default manufacturing cost per hour is provided by
:cite:`stefana:2024`.
"""
[docs]
def setup(self):
self.add_input(
"data:cost:production:manufacturing_man_hours_5_years",
val=np.nan,
units="h",
desc="Number of tooling man-hours required for a certain number of aircraft to be"
"produced in a 5-year or 60 month period",
)
self.add_input(
"data:cost:production:manufacturing_cost_per_hour",
val=72.97,
units="USD/h",
desc="Manufacturing labor cost per hour",
)
self.add_input(
"data:cost:cpi_2012",
val=np.nan,
desc="Consumer price index relative to the year 2012",
)
self.add_input(
"data:cost:production:maturity_discount",
val=1.0,
desc="The discount factor in manufacturing and tooling bsed on process maturity",
)
self.add_output(
"data:cost:production:manufacturing_cost_per_unit",
val=2.0e5,
units="USD",
desc="Manufacturing adjusted cost per aircraft",
)
self.declare_partials("*", "*", method="exact")
[docs]
def compute(self, inputs, outputs, discrete_inputs=None, discrete_outputs=None):
outputs["data:cost:production:manufacturing_cost_per_unit"] = (
2.0969
* inputs["data:cost:production:manufacturing_man_hours_5_years"]
* inputs["data:cost:production:manufacturing_cost_per_hour"]
* inputs["data:cost:cpi_2012"]
* inputs["data:cost:production:maturity_discount"]
)
[docs]
def compute_partials(self, inputs, partials, discrete_inputs=None):
cost_per_hour = inputs["data:cost:production:manufacturing_cost_per_hour"]
cpi_2022 = inputs["data:cost:cpi_2012"]
discount = inputs["data:cost:production:maturity_discount"]
man_hours = inputs["data:cost:production:manufacturing_man_hours_5_years"]
partials[
"data:cost:production:manufacturing_cost_per_unit",
"data:cost:production:manufacturing_man_hours_5_years",
] = 2.0969 * cost_per_hour * cpi_2022 * discount
partials[
"data:cost:production:manufacturing_cost_per_unit",
"data:cost:production:manufacturing_cost_per_hour",
] = 2.0969 * man_hours * cpi_2022 * discount
partials["data:cost:production:manufacturing_cost_per_unit", "data:cost:cpi_2012"] = (
2.0969 * man_hours * cost_per_hour * discount
)
partials[
"data:cost:production:manufacturing_cost_per_unit",
"data:cost:production:maturity_discount",
] = 2.0969 * man_hours * cost_per_hour * cpi_2022