On the 15th May 1941 a small aircraft landed at Cranwell after a flight lasting 17 minutes. The pilot, Fl. Lt. P. E. G. Sayer, got out of the aircraft and was immediately surrounded by an excited group wanting to know how the machine had performed. He answered questions standing by the aircraft and reading from the notes on his knee pad, which he copied on to the paper as shown in Fig. 1. This flight, the first of a Whittle turbojet propelled aircraft, started a new era in aviation. It also marked the beginning of the rapid development of a new heat engine, the fifth since Newcomen’s steam engine.

As you can see from the pilot’s notes, the performance of the E28/39 aircraft in that first flight was modest. An Indicated Air Speed (IAS) of 240 mph was reached. That it was powered by a turbojet can be seen from the readings of rpm, jet pipe temperature, etc. This first engine developed about 850 lb take-off thrust and weighed some 700 lb.

When my colleague, John Carrodus, told me that he was leaving CAA to join Cathay Pacific, he asked me to give the Test Pilot’s Group Lecture in his place. Knowing his inimitable style and ability to regale an audience without pulled punches, I was set a hard task. My work involves little aeroplanes. They are not exotic, like big jets. All of them weigh 6000 lb or less. But I happen to think that I have the best flying job in the country. Much of the piquancy comes from dealing with individuals who are attempting to make a living, and who are sometimes forced to try to cheat the system in order to survive in the face of pressures from the law, paperwork, insurance, more paperwork, inflation and taxation, and still more paperwork; not to mention the emetic CAA.

Standardisation of hardware and procedures is not new to industry in general or the aerospace industry in particular. Sir Joseph Whitworth was a contributor with his thread form, as far back as 1841 and it is still used by industry today. Indeed, one of the major peripheral influences when designing a new product, or engineering it for manufacture, is the need for a logical application of a standardisation policy. This ranges from procedures, practices, materials, methods, treatments and finishes, to the use of hardware. To a very great extent the commercial success of our products in aerospace is dependent upon a sound basis of engineering standardisation, developed over many years with painstaking care.

Most of us engaged in the engineering aspect of our industry have probably had something to do with formulating a standard practice or method, without necessarily recognising it as such. But it is sometimes astonishing how few appreciate the depth to which those concerned with the preparation of a definitive standard need to research, in order to establish the required level of excellence to meet the designers’ specification or production engineers’ planned method for manufacture.

The dangers of using contaminated runways are a continuing concern in the aviation industry. A recent survey has reported on a total of 39 overrun and veer-off cases in the USA between 1962 and 1973 and in 26 of these cases the runway condition was cited as the major cause. The degradation of aircraft landing and take-off performance depends on the depth of water on the runway and thus an instrument is required that will give quick accurate remote estimates of runway water depth without hindering normal operational procedures. A suitable method, using a differential pressure transducer has undergone field tests and the instrument and preliminary results are discussed in this report.

The problem of determining the attitude of a satellite, spinning in space, with its angular velocity being an arbitrarily specified time function, although of significant interest, has long remained analytically intractable in view of the complexity of the non linear coupling in the system of equations governing the Eulerian angles that prescribe the attitude of the satellite. Even the relatively simpler case of a satellite spinning with constant angular velocity poses significant analytical complexity, but has been solved recently. Although, numerical solutions to specific cases are not hard to obtain, the closed form solution, which brings out the inherent properties, is still of interest to the analyst. Accordingly, this study is aimed at an analytical method of solution to the governing equations. It is shown that the three, coupled, non linear, non-autonomous, first order, differential equations can be reduced to a single, equivalent, linear, uncoupled, autonomous equation of second order, through a differential transformation technique. The solution of this equivalent linear equation, is easily obtained and can be mapped onto the original space to derive the Eulerian angles. This backward transformation, using the transformation relations that established the equivalence of the non linear and linear systems of equations, is shown to be feasible as long as certain integrability conditions are satisfied by the input angular velocity time function. The earlier study is easily observed to be a particular case of this generalised analysis.