## 2 Components of Vertiport
### Vertiport Component Sizing
The size of the TLOF pad is 18.4 m, the FATO is 36.8 m, and the safety area is 55.2 m as shown in Figure 2. The EASA [15] regulates the minimum dimensions of the TLOF as 0.83 CD, the FATO as 1.5 CD, and the safety area as the area extended by the greater distance of 3 m or 0.25 CD to the FATO. If the size of the vertiport component is determined according to the EASA regulations, the TLOF pad, the FATO, and the safety area are 15.272 m, 27.6 m, and 33.2 m, respectively, as shown in Figure 3.  
A vertiport supports aircraft takeoff and landing on a vertipad, parking at the gate, passengers getting on and off, recharging, and it can additionally support MRO (maintenance, repair, and overhaul) or aircraft lifting depending on the situation. Since the FAA has not yet formulated rules for vertiport gates, we made assumptions about gate size based on existing heliport rules. The size of the gate depends on the number and size of the specific aircraft to be accommodated. It is not necessary that every gate accommodate the design helicopter. However, the design helicopter is used to determine the separation between gates and taxiways, and the minimum clearance length is one-third CD. Regardless of helicopter size, the minimum clearance between the tail rotor arcs is 10 ft for ground taxi operations. Ground taxi turns of wheeled helicopters are significantly larger than a hover turn [10]. Therefore, the vertiport in this study does not have a separate apron, and additionally supports recharging, passenger embarking/disembarking, and turnaround and has a 21.4 m maximum gate size by adding 10 ft to the CD as shown in Figure 4.  
The EASA [15] also regulates the area supporting the loading or unloading of passengers and cargo, and parking, recharging, and maintenance as'stand'. The stand should provide a circular area with a size of 1.2 times the maximum aircraft dimensions as shown in Figure 5. The EASA also regulates geometry-based stands that include a 3 m protection area. Figure 3: Vertipad size for S-A1 that comply with the EASA’s new regulations. According to a study on ramp operation of commuter VTOL aircraft [16], passengers are not allowed to embark and disembark at the runway when the aircraft's propellers are operating within 200 ft, but the condition was not considered by assuming that eVTOL aircraft does not operate propellers while the passengers are embarking and disembarking. The FAA's EB noted that taxiing is an acceptable practice in vertiports and that the EB revision will provide guidance for vertiport taxiways, taxiways, and helicopter parking. According to AC 150/5390-2C [10], the dimensions of taxiways are a function of helicopter size and type of taxi operations. For the ground taxiways covered in this study, cement, concrete, asphalt, or stabilized surfaces, such as turf, must be provided in accordance with the standards of items P-217 of AC 150/5370-10 [17]. This standard meets the pavement guidelines applicable to the TLOF and FATO in a new document from the FAA. Because taxiways are very close to the touchdown and liftoff areas, for unpaved portions, a turf cover must be provided or the surface must be treated in some way to prevent dirt and debris from being raised by a taxiing VTOL aircraft's rotor wash. Clearance must be secured on both sides of the taxiway so that the minimum size is twice the size of the design aircraft  
Figure 4: Gate size for S-A1 that comply with the FAA’s new regulations. Figure 5: Gate size for S-A1 that comply with the EASA’s new regulations. or 1.5 times the rotor diameter. Since hover guidance requires twice the rotor diameter and ground guidance requires 1.5 times the rotor diameter [10], the overall width of the taxiway was determined to be 27.6 m, which is 1.5 times the CD as shown in Figure 1:0 According to EASA regulation, the transverse slope of a VTOL-capable aircraft taxiway should not exceed 2 percent and the longitudinal slope should not exceed 3 percent.