A simple nacelle comprising a thin cylindrical shell of uniform diameter enclosing an engine, idealised by an actuator disc, is analysed at incidence to a low speed uniform stream for various engine mass flow rates on the basis of a vortex lattice model.

Loadings along the length of the nacelle are calculated, together with the overall normal force, the leading edge thrust on the nacelle nose, and the overall pitching moment. Most of the loading arises over the front part of the nacelle, which is well known. However, there is a significant contribution to the overall pitching moment from the nacelle nose for a nacelle, with engine, at incidence; this effect is absent from a through flow nacelle without an engine. Formulae for ∂CN/∂α and ∂CM/∂α as functions of mass flow rate are derived for a length/diameter ratio of 3:0.

The vortex lattice model developed in Part I has been extended to estimate the overall loads and moments on a cylindrical nacelle alone and on a cylindrical nacelle, enclosing an engine, when the configuration oscillates in simple harmonic motion in an air stream. Results are presented for a range of frequency parameter and thrust conditions. Although the problem is properly posed for low speed flow through the ‘engine’, there is doubt over the model formulation when density changes need to be accounted for.

The flow before and after the partial impingement of a jet on a half plane has been studied. From the extensive mean velocity and turbulence intensity measurements the three basic flow regimes of the main jet flow, the flow over the flat plate and the redirected flow on the flat plate surface have been isolated. The inherited characteristics and axisymmetry of the upstream jet flow and their extent downstream of the flat plate, have also been established. The effect of the leading edge on the flow over the flat plate and the effect of friction on the surface on the redirected flow have also been studied.

A powerful mechanism for the generation of secondary flow, which does not rely on viscous or turbulent stress, is lateral skewing of a shear layer such as that encountered by the body boundary layer in a wing/body junction. For a given entry shear, the characteristics of the secondary flow (a horse-shoe vortex) will depend on the wing nose shape. The effects of three wing nose shapes on the size, position and strength of the horse-shoe vortex have been studied in low-speed flow. As expected, the vortex size and strength increased with nose bluntness; quantitative data describing this effect are presented in this paper. The results include contours of streamwise velocity and secondary velocity plots from which vorticity contours and a non-dimensional circulation were derived. The results should be of use in wing design where this secondary flow needs to be controlled.

With the close relationship which exists between the airline industry and aerospace, it is appropriate to begin an aerospace technology symposium with a short review of what the airline industry has achieved and where it is now going. The timing is similarly appropriate because it is the 50th anniversary of the true beginnings of the airline industry. Boeing introduced its B247 into service at the end of 1933, and Douglas followed with its DC2 in 1934. Both aircraft were major steps from previous technology, and created the equipment base from which air transportation could develop. At the same time, the Air Mail Act of 1934 created the organisational environment in which the industry could flourish and, inter alia, compelled Boeing and United Aircraft to divest themselves of airline interests and marked the true beginning of United Air Lines. TWA and American had preceded it by a few months, while General Motors were persuaded to sell off Eastern Air Linesonly a few weeks later.