Flying ad-hoc networks （FANET） using directional transmissions face challenges during network initialization due to frequent topology changes and fluctuations in link quality. To address these issues， a sensing-assisted rapid neighbor discovery method is proposed. The main idea of this method is to use a sensing mechanism to obtain neighbor node information， which accelerates network efficiency. In addition， this paper describes the adoption of a new integrated sensing and communication waveform， known as multiple-input multiple-output （MIMO） orthogonal time-frequency space （OTFS），which combats the Doppler effect in fast-changing channels and improves link quality. For FANET scenarios， a multi-target detection technique based on MIMO-OTFS integrated sensing and communication waveforms is studied at the physical layer. This physical layer sensing scheme is then mapped to the upper layer network， and a sensing-assisted efficient neighbor discovery algorithm is designed. Additionally， a integrated sensing and communication mechanism for collaborative discovery of multi-point is proposed. This mechanism indirectly senses and discovers potential targets by interacting with sensing information and neighbor discovery tables among neighboring nodes. The proposed mechanism enhances the initial networking efficiency of FANET. Simulation results demonstrate that the proposed scheme outperforms pure communication protocols. This leads to a significant reduction in the initial networking time of FANET， an increase in target sensing accuracy， and an overall improvement in network performance.