The advantages to a Navy of an aircraft which can operate from a relatively small deck area are enormous and it is not surprising that the British as a maritime nation were in the forefront of the development of rotary wing aircraft for use at sea. However, the first man to land a rotary wing aircraft on a ship other than an aircraft carrier was an ex-Royal Air Force Officer R. A. C. Brie and the ship was the Italian cruiser Fiume.

Flying locust swarms have already been found to provide particularly efficient three-dimensional targets for ultra-low-volume aircraft spraying. An exceptionally large proportion of the total insecticide applied can be picked up on the insects themselves, and kills exceeding one tonne of locusts per litre of insecticide have been assessed in the course of such operations. There is reason to believe that it was by aircraft spraying of swarms, often in flight, in Morocco during 1960, that locust control operations may for the first time have had a significant impact on the overall Desert Locust situation. Similar operations during 1968, in Ethiopia (with an outstanding Ethiopian senior pilot, Ato Abebe Wordofa) and again in Morocco, appear to have played a considerable part in suppressing the unusually short-lived recent upsurge of the Desert Locust, Schistocerca gregaria Forskal.

Although the concepts of “efficiency” or “coefficient of performance” are useful in relating the output to input energies of a system, they do not give any indication of the manner in which this input energy varies within the system.

This shortcoming may be overcome by using “energy flow diagrams” which have the great advantage of providing a pictorial, yet mathematically accurate, representation of the energy balance of the system, from which an overall appreciation of the energy variations can be obtained at a glance.

The simplest practical type of flow involving separation is that past a smooth flat plate with uniform velocity U0 at inlet followed by a linear adverse velocity gradient dU/dx = Constant (Fig. 1). At first the boundary layer is laminar up to the transition point xL. The turbulent boundary layer then grows with uniform potential flow velocity U0 outside the boundary layer up to the point x1 From x1 downwards the boundary layer grows in the presence of an adverse pressure gradient and finally separates at the point xs.

Since its creation in 1964, Intelsat has launched and positioned 10 satellites in synchronous orbit. The first of these was Intelsat-I, known as Early Bird, launched in April 1965; the most recent was Intelsat-IV (F-2), the first of a new series of Intelsat satellites. The IV (F-2) was launched in January 1971 and entered into service during March in the Atlantic Ocean area. The next Intelsat-IV satellite is scheduled to be launched later this month for positioning in the Atlantic Ocean area also. Subsequent Intelsat-IV launches are scheduled for 1972 and 1973.

In many disciplines, cartography included, it is a requirement to discover or to measure what is on or in the Earth. Detailed investigation on the surface by itself is clearly non-optimum, for logistic and other reasons. Even in Roman times, when labour was cheap, it is learned that mineral deposits in this country were located by observation from high ground of places where the early morning frost first cleared under the rising sun; presumably this was followed up by detailed work on the identified spots.