During airport ground navigation, aircraft pass close to obstacles such as buildings, other aircraft or ground vehicles These obstacles can be located at few meters from the antenna. In this context, modeling the antenna plus aircraft system as a radiation pattern is not justified due to the far-field hypothesis. To overcome this issue, the idea proposed here is to reduce the size of the radiating element to the antenna itself and to account for the aircraft structure in another way. To do so, the antenna plus aircraft is divided into 3 zones which contributions are dealt separately: the antenna is seen as gain, phase and group delay patterns, the fuselage in the near field of the antenna is modeled as a single multipath and the rest of the aircraft is considered as a source of multipath. Then, by means of the theorem of superposition, the different contributions are gathered to get the complete antenna+aircraft model.