The trailing vortex wake shed by large transport aircraft not only has detrimental effects on their aerodynamic efficiency through the production of induced drag but can cause a considerable safety hazard to smaller following aircraft. This hazard is a major factor in determining the minimum allowable spacing between aircraft during airport operations with separations of up to five nautical miles being required between heavy aircraft and smaller aircraft following them on the approach for landing. It has been estimated that the minimum safe operating distance based on considerations other than vortex wake hazard is approximately two nautical miles’. The potential economic saving from the reduction in operating times at busy airports as well as the improvement in aerodynamic efficiency has led to the investigation of many schemes for the alleviation of these trailing vortices.

Autonomous shipboard launching of UAVs in a hostile atmospheric environment would greatly extend the usefulness of these aircraft. Currently a majority of UAVs are remotely launched under limited conditions. This paper presents control and guidance strategies that will allow autonomous launching under a much greater set of atmospheric hazards. Two modern control techniques are compared for use in this case. The main problem when dealing with low speed UAVs is found to be high steady winds causing stall. Several strategies are presented that can allow stall to be avoided and recovered.

There is a popular misconception that synthetic training is only concerned with time spent in the simulator. If this were so, a training exercise which had focused on the simulation experience alone, might fail to provide the rich learning environment needed to maximise training opportunities and so fall short of expectations in terms of delivery of a complete training experience.

This is particularly true when considering collective training for military aircrew; where all mission phases are equally important, and all roles and tasks must be carefully considered when assessing the training need. The training designers must create a scenario that meets the requirements of the total training audience (the collective) throughout all the mission phases; planning, briefing, flying (traditionally the key simulation event) and debriefing. This scenario must allow the trainees to become fully immersed and provide a ‘total experience’ in order for them to obtain maximum benefit from the synthetic training event.

Maintenance of such an environment during the training process places an extra burden on those who are providing the training experience. As the number and mix of trainees participating in a synthetic exercise grows so too do the demands placed upon the exercise management team, the trainers and the assessors to provide a rich and rewarding training experience. Not only must these key personnel be carefully selected, their needs must also be taken into account during the training design process. This will help to ensure that transformation of data to information and information flow is optimised for all participants.

Recent experience in mission training via distributed simulation has shown that greater training opportunities can be afforded if the training designers address the needs of all the above. Using these experiences as reference points, this paper will discuss synthetic training issues along with the expectations of the trainees and the training providers and suggest some guidelines for creating a total training experience.

The flow field produced by the orthogonal blade-vortex interaction (BVI) was examined through the application of a particle image velocimetry (PIV) technique, and acquisition of comparative unsteady surface pressure measurements. The velocity vector maps obtained revealed a significant radial flow from the vortex core after severing, in the form of an outward flow from the core when the flow is directed towards the surface (lower), and inward when directed away (upper). With progression of the vortex over the chord of the blade, the interaction led to a decrease in peak vorticity levels on the lower surface, but a steady level was maintained on the upper surface. Assessment of the effect of the interaction on the out-of-plane mass flux was performed through calculation of the divergence, revealing that there is no further variation in the axial flow on either side of the blade after the initial cut.

An aeroelastic formulation of 2D lifting surfaces in an incompressible flow field via the use of aerodynamic indicial functions is presented. The approach carried out in time and frequency domains yields the proper aerodynamic loads necessary to the study of the subcritical aeroelastic response and flutter of lifting surfaces, respectively. The expressions of the unsteady lift and aerodynamic twist moment in the frequency domain are given in terms of the Theodorsen’s function, while in the time domain, these are obtained directly with the help of the Wagner’s function. Closed form expressions of unsteady aerodynamic derivatives, helpful in an unified approach of response and flutter analyses, and results related to aeroelastic response to gust and blast loads are supplied. In this context, a novel representation of the aeroelastic response in the phase - space was supplied and pertinent conclusions on the implications of some basic parameters have been outlined.

There is widespread and growing interest in the potential use of distributed simulation for aircrew team and collective mission training for military operations. Live flying training is becoming increasingly limited due to a combination of factors, including lack of airspace availability, environmental and security constraints, concern about consumption of aircraft flying hours and airframe life, the cost of major exercises and limited opportunities to practise co-ordination of critical multi-national NATO air missions in a representative operational environment, complete with threats. Furthermore, peace-time constraints typically preclude full operational use of electronic warfare (EW) systems, deployment of defensive aids such as chaff and flares and firing of live weapons. Data links are also extending the ‘tactical reach’ of an air package. Thus, training methods have to adapt.