For a standardized RC calculation the NASA RC Method (NASA CR 151970) by Beltramo et al. and the Engine Price CER by Langhans have been chosen. The formulas have been implemented into a RC tool that calculates all RC parts for a given CPACS file. The RC tool as well as a summary of all RC formulas is given in the following. Please note, that in the summary the unit of the DOC parts is [€] whereas the unit used in the tool as well as in the aircraft design analysis is [$].
RC tool
With the RC tool all RC parts are automatically calculated for a given aircraft in CPACS format and written into the CPACS file. Therefore the executable and the CPACS file have to be in the same folder. In the rcTool-config.xml the program settings like the name of the CPACS-file to be analyzed as well as scenario settings like the number of aircraft to be produced have to be set.
You can dowload the RC tool with a CPACS-file example here (.zip): rcTool.zip
Summary of RC formulas
A summary of the used RC formulas, based on the NASA RC Method and S. Langhans, is given in the following and can be downloaded here: RCMethod CeRAS NASA
General information
- All monetary values in 2010-€
- Overall unit: €
- U.S. Dollar exchange rate: 1 USD = 0.72 €
- CPI factor (1975-USD to 2010-USD): 4.05
- CPI factor (2001-USD to 2010-USD): 1.23
(see: http://stats.bls.gov/cpi/cpifiles/cpiai.txt)
\[\begin{aligned} RC =\sum{C_{i}} + C_{LoadAndHandling} + C_{FinalAssemblyAndDelivery} + n_e \cdot P_e \end{aligned} \]
- RC: Recurring costs of one aircraft (average value) [€]
- Ci: Recurring costs of system i [€]
- Pe: Price of one equipped engine [€]
- ne: Number of engines
RC of aircraft systems
\[\begin{aligned}
C_{i} = c_{1975} \cdot \alpha \cdot {W_{i}}^{\beta} \cdot Q^{\gamma}
\end{aligned} \]
\[\begin{aligned}
C_{LoadAndHandling} = c_{1975} \cdot \frac{W_{LoadAndHandling}}{W_{Fuselage}} \cdot C_{Fuselage}
\end{aligned} \]
\[\begin{aligned}
C_{FinalAssemblyAndDelivery} = 0.25 \cdot (\sum{C_{i}} + C_{LoadAndHandling})
\end{aligned} \]
- Ci: Recurring costs of system i [€]
- Wi: Weight of system i [lb]
- Q: Production quantity
- c1975: Conversion factor [2010-€/(1975-USD)]: 2.916
- α,β,γ: CER coefficients see table 1