# Improvement of Boeing Bump Method Considering Aircraft Vibration Superposition Effect
## 3 Simulation of Aircraft Dynamic Response
### Typical Aircraft Virtual Prototype Models  
ADAMS/Aircraft software includes templates for various parts of an aircraft's structure, which allows users to modify the parameters slightly. However, the only type of aircraft for which the templates apply is a military aircraft, which is quite different from civilian airliners. In order to carry out simulations for civil aircraft, we have built several additional civil aircraft models to complete the ADAMS/Aircraft database. Boeing and Airbus occupy the mainstream presence in the current international civil aviation market. Table 1 presents the classifications for the different Boeing (B) and Airbus (A) models.  
Based on the representative aircraft types presented in Table 1, we selected five typical Boeing aircraft types for this study to build virtual prototype models: B737-800, B757-200, B777-300E, B787-800, and B747-400. Figure 3 shows these five models assembled in ADAMS/Aircraft.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Type** & **Models** & **Wingspan/m** &
\begin{tabular}{c} **Main Landing Gear** \\ **Outer Wheel Spacing/m** \\ \end{tabular} \\ \hline C & B737, A320 series & 24–36 & 6–9 \\ D & B757, B767 series & 36–52 & 9–14 \\ E & B777, B787, B747, A330, A340 & 52–65 & 9–14 \\ F & B747, A380 series & 65–80 & 14–16 \\ \hline \hline \end{tabular}
\end{table}
Table 1: Aircraft model classifications [16].  
Figure 2: Iconic flowchart of the modeling and assembly process [10].  
Using the B787-800 as an example [17], Table 2 shows the parameters used for the fuselage, landing gear, and wheel. The stiffness and damping ability of the landing gear system were considered using landing gear buffer model. Detailed information about landing gear buffer model can be found in authors' previous publication [10].  
\begin{table}
\begin{tabular}{c c c c c} \hline  & length of fuselage & 55.91 & engine bottom & 0.74 \\  & /m & & height above & 0.74 \\  & & & ground /m & \\ \cline{2-5} geometric parameters & wingspan/m & 60.12 & distance between engine and fuselage & 9.72 \\  & & & axis/m & \\ \cline{2-5}  & nose height from & 3.5 & distance between engine and nose/m & 17.78 \\  & ground/m & & & \\ \cline{2-5} fuselage & & maximum takeoff & 227,930 & maximum landing weight/kg & 172,365 \\  & weight parameters & distribution & 91.2\% & distance between center of gravity and nose landing gear/m & 20.8 \\  & & & height & \(\rm gear/m\) & \\ \cline{2-5}  & & maximum takeoff & 227,930 & maximum landing weight/kg & 16,966,788 \\ \cline{2-5} fuselage & weight parameters & distribution & & distance between center of gravity and nose landing gear/m & 7.52 \\  & & coefficient of main landing gear & & \\  & weight & & & \(\rm gear/m\) & \\ \cline{2-5}  & moment of inertia & \(\rm I_{x}/kg\cdot m^{2}\) & 9,329,171 & \(\rm I_{y}/kg\cdot m^{2}\) & 16,966,788 \\ \cline{2-5}  & & \(\rm I_{z}/kg\cdot m^{2}\) & 25,475,812 & & \\ \hline  & wing reference area & 325 & pneumatic chord length & \\ lift parameter & /fitm\({}^{2}\) & & & /m & \\ \cline{2-5}  & aspect ratio & 8 & & \\ \hline  & & nose main landing gear & 22.78 & main landing gear wheel & 1.3 \\  & & spacing/m & pitch/m & \\ \cline{2-5}  & geometric parameters & main landing gear & 9.8 & nose landing gear & 1.24 \\  & & spacing/m & & total length/m & \\ \cline{2-5} landing gear & & nose gear wheel & & \\ \cline{2-5}  & gear & pitch/m & & \\ \cline{2-5}  & & nose landing gear & & \\ \cline{2-5}  & fluid & damping parameter & & \\ \cline{2-5}  & damping & nose landing gear & & \\ \cline{2-5}  & extension damping & & & \\ \cline{2-5}  & parameter & & & \\ \hline \end{tabular}
\end{table}
Table 2: Virtual prototype model of B787-800 and parameters [17].  
Figure 3: Virtual prototype models of typical Boeing aircraft assembled in ADAMS/Aircraft.