The ongoing revolutions in information, biological, energetics and nano technologies are changing the nature and equipment of warfare. This is particularly true in military aeronautics. In the nearer term aircraft are becoming increasingly ‘uninhabited’ (UCAVs, UAVs etc.) enabled by the IT revolution, with multitudinous accompanying benefits in terms of affordability, survivability, redefinition of ‘risk’ and lethality. THE issue for such aircraft is enhanced persistence and increased range within the context of the overall system metrics. In the longer term the increasingly capable worldwide ‘sensor web’ will place at risk all air vehicles, in or out of theatre and whether or not they are ‘stealthy’. This, combined with advanced conventional weapons, high energy density material powered EMP (electro-magnetic-pulse) weapons and affordable swarms of ‘brilliant’ munitions will probably require yet another re-definition of military aeronautics, perhaps as survivable (hardened) hypersonic, global range, boost-glide devices.

This paper presents a simple and efficient way of calculating stall flutter using the ONERA aerodynamic model. At first, the model is presented along with a solution technique based on the harmonic balance method. The parameters of the model are estimated using data either from experiments or CFD calculations and optimised using the Levenberg-Marquardt algorithm. The aerodynamic model is then coupled with a structural one using the Rayleigh-Ritz formulation and a solution technique is devised based on the Newton- Raphson method. Finally the model is used to ‘fit’ aerodynamic loads of oscillating aerofoils generated using CFD. The aeroelastic analysis of a helicopter blade is finally undertaken using material properties found in the literature. The model appears to be robust and efficient and able to fit the unsteady aerodynamics of various cases. The proposed aeroelastic analysis was also found to be efficient and capable of providing adequate results for preliminary analysis of stall flutter.

Flight simulation has become an indispensable tool for aviation training. Important decisions relating to the acquisition and certification of aircrew proficiency are made based on performance in simulated flight conditions. Such a high dependency on simulation can invite questions about the validity of the assumptions on which their employment is founded. If these should be shown to be in any way deficient, those who consider that they have suffered as a result may seek redress. The paper considers the possibility that such conditions could arise and require those involved in the design, manufacture, regulation and operation of flight simulators to justify their decisions. The paper suggests that the culture should be one which acknowledges that simulation has its limitations and, consequently, exercises a duty of care for those who undertake training and assessment in flight simulators.

At 14h42 UTC (3.42pm BST), on Tuesday, 25 July 2000, Concorde F-BTSC, operated by Air France, started its take-off roll on runway 26 Right at Paris Charles de Gaulle, to undertake a charter flight to New York with nine crew and 100 passengers on board. Shortly before rotation, the front right tyre of the left main landing gear ran over a strip of metal, which had fallen from another aircraft, and was damaged. Debris was thrown against the bottom wing surface leading to a rupture of tank five. A major fire, fuelled by the massive leak, broke out almost immediately under the left wing. Problems appeared shortly afterwards on engine two and for a brief period on engine one. The aircraft took off. The crew shut down engine two following an engine fire alarm. The landing gear would not retract. The aircraft flew for about one minute at a speed of 200kt and an altitude of 200ft, but was unable to gain height or speed. Engine one then lost thrust, the aircraft’s angle of attack and bank increased sharply. The thrust on engines three and four fell suddenly. The aircraft crashed onto a hotel at Gonnesse. Everyone on board and four people in the hotel were killed.

This paper describes the development of an approach to handling qualities investigation that can be applied at an early stage in t he design of the vehicle. It makes use of inverse simulation techniques, together with a pilot model to provide an integrated description of the man-machine control system. In order to incorporate pilot effects into data generated by inverse simulation, the output from an inverse simulation run is applied as input to a closed-loop system model that includes the vehicle dynamics and a simple parametric model of the pilot. Parameters of the pilot model are determined by optimisation and the pilot effect is added to the system output. Validation of the approach is achieved through a case study involving a predefined mission task involving a lateral manoeuvre. Equalisation characteristics estimated for each pilot are compared with those found by inverse simulation for the same manoeuvre. This approach may be applied using a simple real-time simulation on a desk-top computer and could be of value in identifying any potential deficiencies in a helicopter flight control system at an early stage in its development