At the heart of a flight simulator resides the mathematical representation of aircraft behaviour in response to control inputs, atmospheric disturbances and system inputs including failures and malfunctions. While this mathematical model can never be wholly accurate, its fidelity, in comparison with real world behaviour, underpins the usefulness of the flight simulator. The present paper examines the state of the art achieved in validating mathematical models for helicopter simulators, addressing the strengths and weaknesses of the present European standard for the qualification of helicopter flight simulators, JAR FSTD-H (previously JAR-STD-1H/2H/3H). Essential questions are examined, such as: What is the required model fidelity to guarantee a simulation is sufficiently representative to be fit for purpose? Are the tolerances set in the current standards fine enough that they lead to only minor changes in handling qualities? What is an acceptable tuning process for the simulation? What is the effect of modelling fidelity on the overall pilot control strategy? What is the relationship between the settings of the simulator cueing environment and the behaviour of the pilot? What is the industrial experience on qualification of flight simulators that might usefully inform developments? Many of these questions were addressed in Europe in a previous GARTEUR Action Group (AG) HC/AG-12 the results of which are documented in this paper. Solutions are proposed for improving the current JAR-FSTD standard with respect to validation of mathematical models.

The success of the MV-22 Osprey has created the opportunity for a new design of gunship, tailored to the task of escorting it, an opportunity identified by many. Existing and emerging rotorcraft technology does not appear to have the complete capability, so this centre-line tiltrotor approach is aimed specifically at the escort duty.

The mission is taken to be escorting the MV-22 throughout a land assault (Marine Corps), to provide cover while the MV-22 is on the ground at the landing zone, and to still have useful capacity for diversions. To meet this task this Escort concept stays with the same core physics of tilting rotors plus fixed wings of the Osprey, but re-configured for gunship duties. The rotors are removed from the wing tips to mount them on the aircraft centre-line as inter-meshing rotors tilting back one-at-a-time, to act as pusher props in the aeroplane mode. The merits and concerns of this approach are discussed.

The study first reviews present tiltrotor technology and how that may develop. It then reviews what may be achievable from the centre-line tiltrotor configuration, the targets needed in key design parameters and design sensitivities, defining what the enabling technologies must achieve for the Escort. In hover, key areas are rotor disk loading and figure of merit, and also the rotor blockage caused by the fuselage and wings. In winged flight, the proprotor propulsive efficiency and the aircraft lift-over-drag are key, and fundamental to the feasibility of any tiltrotor concept, there is the all important transition process.

At this conceptual stage of the Escort, the transition process stands out as the dominant risk, and one that touches on all the others, so it was decided to build and flight test a model. The flight test programme plans are described and initial flight results reported.

The authors have recent experience of the specification, procurement, customisation and operation of advanced air traffic control simulator systems. This paper summarises the specification of the software and hardware components of air traffic control simulators within a framework of user needs and advances in simulation technology. Both the required conventional characteristics and the desired innovative features which can accommodate future requirements are defined using taxonomy within this framework. Considering the high investments and challenges involved in the acquisition and operation of modern simulators, the proposed classifications and approaches will provide important benefits to users when selecting or renovating their systems.

In this paper computation of high resolution, compressible condensing/evaporating moist-air flow for a series of two-dimensional internal and external flows is performed. It has been observed that the inflow wetness content can change the aerothermodynamics of the flow field, e.g. the shock angles. In the case of flow expansion through nozzles, it has also been observed that the content of wetness at nozzles exit in the case of moist-air is more than five times higher than that of pure steam under similar operating conditions. The reason is due to the internal flow of heat from steam portion toward air that accelerates the steam condensation rate. The solver is spatially third- and temporally second-order accurate. Validations of the numerical code are performed versus the experimental data of Moore et al (1973) in the case of very large humidity ratio, ω→∞ (pure steam). Also in the case of low humidity ratio, ω→0 (dry air), the exact solution of shock tube and wedge cases are used to validate our numerical results.

The flow past an unmanned combat air vehicle (UCAV) 1303 was investigated in a water tunnel in an effort to understand the complex flow field. The UCAV 1303 is characterised by a non slender, 47° swept-leading-edge delta wing, with a cranked trailing edge, a cropped wing tip and a fuselage. It also has no vertical tail. Dye visualisation pictures and five-axis strain gage load data were obtained on a 1:72 scale model in both steady flow and while the model executed preprogrammed manoeuvres. From the strain gage data, body axis force and moment data were derived. In addition to some similarities, comparison of the flow features observed with those of more well known slender delta wing flows showed some remarkable differences such as tip-stall, the presence of two like-sense vortices on the same side of the wing, their simultaneous spiral and bubble bursting. This paper predominantly discusses the flow visualisation results and attempts to correlate the load data to some of the observed flow features.