When conducting landings to a ship's deck in strong winds, helicopter pilot workload is often dominated by the turbulence within the ship's airwake. Previous studies have shown that larger ships create more aggressive airwakes and simulated flight trials had shown that it can be easier to land to a smaller ship than a large one. However, there are helicopter-enabled ships that are less than 100m in length and these will have significantly greater ship motion in rough seas than a large ship. The study reported in this paper has used a motion-base flight simulator to evaluate the pilot workload when landing to three geometrically similar ships of lengths 100m, 150m and 200m. Ship motion software has been used to create realistic deck displacements for sea states 4, 5 and 6, which are consistent with the increasing wind speed over the deck. It has been shown that the 100m ship was the most difficult to land to, with deck motion being the limiting factor. The next most difficult ship to land to was the 200m ship, with airwake turbulence being the limiting factor. The 150m ship generated the lowest pilot workload. The study has demonstrated that when ship motion is excessive, as it will be with small ships in rough seas, pilot workload will be dominated by deck motion during a landing task, but as the ship gets larger and more stable, airwake disturbances will dominate. It is clear from this study that realistic ship motion is essential when using piloted flight simulation to conduct simulated ship-helicopter operations
