An experimental study investigating the aerodynamic characteristics of generic delta wing-body combinations up to high angles of attack was carried out at a subsonic Mach number. Three delta wings having sharp leading edges and sweep angles of 50°, 60° and 70° were tested with two forebody configurations providing a variation of the nose fineness ratio. Measurements made included six-component forces and moments, limited static pressures on the wing lee-side and surface flow visualisation studies. The results showed symmetric flow features up to an incidence of about 25°, beyond which significant asymmetry was evident due to wing vortex breakdown, forebody vortex asymmetry or both. At higher incidence, varying degrees of forebody-wing vortex interaction effects were seen in the mean loads, which depended on the wing sweep and the nose fineness ratio. The vortex breakdown on these wings was found to be a gradual process, as implied by the wing pressures and the mean aerodynamic loads. Effects of forebody vortex asymmetry on the wing-body aerodynamics have also been assessed. Comparison of Datcom estimates with experimental data of longitudinal aerodynamic characteristics on all three wing-body combinations indicated good agreement in the symmetric flow regime.

A simple model is presented for an aerofoil with a recirculating Prandtl-Batchelor region behind a spoiler. Using thin aerofoil theory the model is posed as a pair of coupled nonlinear singular integrodifferential equations for the shape of the separating streamline and the distribution of vorticity along the aerofoil. These equations are solved numerically and results are presented. In particular, some conclusions are drawn regarding the lift on such aerofoils.

Recent experiments have demonstrated that humans can fly, with great exertion of the leg muscles using fixed wings and a propeller. However, understanding of aerodynamics and physiology show that using existing technology it is not possible for humans to fly on Earth using their arm muscles to flap wings like birds. Human flapping flight might, however, be possible in a partial gravity environment such as a chamber in Earth orbit or on the surface of the Moon. This paper considers the feasibility of this and provides preliminary estimates of the main parameters involved.

Reliability and safety criteria have, in one form or another, made a significant contribution to engineering design since the earliest times. They gained added significance in Victorian times as the scale of civil and mechanical engineering projects increased. Codes of practice came into use, based both on practical experience and theoretical knowledge. Redundancy and diversity, though not given those names, were introduced as a means of achieving improved reliability and safety. Reliability and safety technology in the modern sense only developed, however, when predictive techniques, based on statistical information, were introduced. This technology has now taken its place in a wide range of engineering activities and is adopting an increasingly international role. It makes use of numerical reliability and safety goals and pays attention to problems associated with human reliability and ergonomics. This paper reviews the particularly important contribution made by civil aviation to the development of present day reliability and safety technology.

The teaching of aircraft stability and control at university usually progresses to the complexity of six degrees of freedom with a large array of aerodynamic, gravitational and inertial terms. It is therefore essential to ensure that students have a good grasp of fundamental dynamic characteristics such as damping and natural frequency, and any demonstration in which students observe aircraft motion is particularly helpful. At Manchester University this is achieved by a windtunnel demonstration of aircraft dynamic stability and response in pitch to a sinusoidal gust generator.