Having in mind the above considerations, now it is evident the importance of the accurate evaluation about the baseline between the RPAS and the hangar that are linked by means of an extensible (not fixed) cable. During current experimental activities (documented in section 1.3.1) we’re experiencing as having the possibility to monitor the baseline can provide a significant improvement with clear impact in reliability (it avoids excessive mechanical stress to extensible cable) and efficiency of operations (above all during cable deployment and winding). Moreover, RPAS semi-automatic take-off and landing are critical phase too as performed on board a ship, which is moving. More importantly, the landing area is narrow on a ship, and interference related to the maritime environment due to wind disturbance and wave motions varies greatly, making maritime RPAS landings quite difficult. In order to land RPAS in such a rapidly changing environment requires a high-precision navigation system on-board RPAS. According the Joint Precision Approach and Landing System (JPALS), the requirements of shipboard landing include vertical accuracy on the order of 0.3 meters, and the requirement for the vertical protection level is 1.1 meters. To meet these accuracy requirements, the consortium is looking to investigate the use of RTK. This focus is particularly interesting as the claimed performances have to be reached in a dynamic environment such that it involves moving base RTK that makes it very challenging to meet high positioning accuracy requirements. In this framework, the SARA project will be an important occasion to verify these techniques and to confirm results that are preliminary documented in existing literature. Considering the aforementioned challenges, the EGNSS technology represents an essential asset and it is noteworthy that EGNSS receivers installed on board the RPAS may also allow to better evaluate the attitude and in particular the azimuth which is important to detect the survivors position with reference to the ship location.