Shipboard/rotorcraft simulation and analysis

This research has simulated the rotorcraft on-deck dynamic interface for defining safe operational conditions and for the first time, compared the results of studies with measured performance stability data. A comprehensive interface simulation and analysis of rotorcraft shipboard on-deck operational envelopes were developed in FLIGHTLAB (a software tool for rapid prototyping and interactive evaluation of simulation models). The helicopter was modeled using a blade element model and the ship airwake was simulated using Computational Fluid Dynamics (CFD) data. Investigations showed that the ship speed, the ship heading, the rotor speed, and sea conditions significantly influence rotorcraft on-deck handling.; Dynamic interface studies used the FLIGHTLAB to simulate the SH-60B Helicopter operating from an LHA class ship to properly quantify shipboard rotorcraft operational capabilities under various conditions. Hazardous flight conditions such as high winds, low visibility, a moving-landing platform and unusual airflows around ships can have significant effect on pilot workload and crew safety. The dynamic interface problem involved the determination of shipboard rotorcraft operational performance and envelope. The unique problem areas for current simulation studies include ship airwake, turbulence modeling and rotorcraft/ship aerodynamics. The rotorcraft/ship interaction is a problem of two-way interference. On the one side, the ship's induced airwake affects the rotors and airframe aerodynamics due to changes in their angles of attack and dynamic pressure variations. On the other side, the rotors or airframe induced wake impacts the ship's deck/structure to alter the airwake distribution. Encouragingly, results from research have shown good correlation with measured data.