Experiments and computations have been made to obtain the details of the flow field over a slender body at high angles of attack at a freestream velocity of 17 m/s corresponding to a Reynolds number of 2.9×104 based on the base diameter. Experiments indicated that the existence of side force at higher angles of attack is mainly due to the presence of asymmetric vortices in the leeward side. A rectangular cross-section circular ring placed at an axial distance of 3.5 times the base diameter reduced the side force at all the angles of attack. Investigations were made to obtain the effect of the height of the ring at an angle-of-attack of 50° where the side force experienced is relatively large. A ring placed at a distance of 3.5 times the base diameter alters the initial vortices and hence helps in substantial reduction of the side force. Studies with rings of different heights indicate that a ring having a height of 3% of the local diameter reduced the side force at almost all the angles of attack for the present flow conditions and provided the least disturbance to the lift and drag of the body.

The 150th anniversary of the Royal Aeronautical Society has seen Rolls-Royce become a global player in aerospace and a champion of British industry. Its products vary from the nimble RR300, powering two-seater helicopters, all the way to the 97,000-pound thrust Trent XWB, powering future variants of the Airbus A350, and the MT30, which provides the propulsion for the Royal Navy's new Queen Elizabeth class aircraft carriers. It has built this range of products derived from the vision and innovation of its talented engineers, spurred on by the guiding principles provided by Henry Royce. This has seen it through times of war, hardship, bankruptcy and fierce competition to emerge as the leading manufacturer of aircraft engines and a provider of power across land and sea. Alongside its products, it has developed pioneering services to support its customers, analysing real-time data to improve the reliability and efficiency of its engines. In keeping with its tradition of innovation, the company is continuing to develop new products and services for the next generation of power systems for land, sea and air.

The present paper focuses on a three-dimensional unsteady turbulent synthetic jet to assess the accuracy of a compressible simulation and some important parameters including the simulations of the actuator, cavity height and Reynolds number. The two-equation SST/k − ω turbulence model is used to predict the flow behaviour. Results show that the compressible simulation case is more accurate than the incompressible one and the dynamic mesh exhibits more reliable results than the mass flow inlet boundary in the compressible simulation. The compressible case displays a delay in the phase of instantaneous velocity for all three Reynolds numbers. Also, the maximum of mean velocity is less than the incompressible case. Moreover, an increase in the Reynolds number leads to an amplification of the peak of mean velocity magnitude. Finally, results demonstrate that a reduction in the cavity height regarding the compressible simulation case causes a reduction in the phase delay and rise in peak of instantaneous velocity magnitude.

Simultaneous modelling of aerodynamics, structure and flight dynamics is used to predict the gust loads on a model of 18-metre wingspan sailplane that includes bending flexibility. The ASWING software is used to analyse the time history of the wing-bending moment and the shear force at the wing root for the design gust speed and for the design maximum speed at different wavelengths of a ‘1-Cosine’ gust. Maximum values from the time history were compared with certification requirements for rigid sailplanes. The analysis revealed that wing-bending flexibility reduces the loads.

Steven Ford was omitted from the list of authors in the article by Murrieta-Mendoza(1). The correct authorship is:

A. Murrieta-Mendoza, R. Mihaela Botez and S. Ford

The article has now been updated with the correct authorship; this change has been made to the online version only.

The authors were listed incorrectly in the article by Zanotti(1). The authors should have appeared in the following order:

G. Gibertini, A. Zanotti, G. Droandi, D. Grassi, G. Campanardi, F. Auteri, A. Aceti and A. Le Pape

The article has now been updated with all authors listed in the correct order. This change has been made to the online and print PDF and HTML copies.

The general picture of research in active flow control for aircraft applications has been continuously changing over the last 20 years. Researchers can now obtain design sensitivities by using numerical flow simulations, and new optical experimental methods can be used that measure flow field data non-intrusively in planes and volumes. These methodological advances enabled significant knowledge increase. The present paper reviews recent progress in active flow control by steady blowing. It appears that two strategies of blowing deserve particular attention. The first uses tangential blowing of thin wall jets to overcome the adverse pressure gradients from locally very large flow turning rates. This approach exploits the potentials of the Coanda effect. The second strategy employs oblique blowing of air jets designed to generate longitudinal vortices in the boundary layer. The longitudinal vortices provide convective redistribution of momentum in the boundary layer, and they also enhance turbulent momentum transport. The sensitivities of these two approaches as observed in fundamental flow investigations and in applications to high-lift aerofoils are described and suited efficiency parameters of blowing are analysed.

In the last century and a half, space has moved from the realm of fantasy to everyday reality. In parallel, the way space has been regarded by the person in the street and the ideas of what access to space might be used for have evolved extraordinarily.