· · · Aerospace Engineering reports

The two-dimensional hypersonic sail is examined using the Newton-Busemann pressure law. The results are compared with those of Daskin and Feldman (1958) who used the empirical modified Newtonian pressure law. It is found that for a given chord length of sail a corrected sail will give a specified lift for a smaller tension in the sail. At a flight Mach number of 10 at 100,000 ft, the tension in one particular sail considered could be supported with a working stress of about 20 tons/in². The College of Aeronautics was founded in 1946 and was granted university status in 1969 becoming the Cranfield Institute of Technology. In 1993 it changed its name to Cranfield University.

The review derives and presents the equations which govern the free uncoupled flexural and torsional vibrations of an untwisted beam rotating at uniform speed. Consideration is given to the effects of an elastic hinge at the root and of a concentrated mass at the tip. The variation due to these effects of the first three natural frequencies of the root bending moments, torques and shear forces is given in the form of graphs .

A review of some recent investigations in the flow of h i ghly rarefied gases is presented. The basic nature of the transport process in free molec ule flow is deduced from the Boltzmann equation for the molecular velocity distribution function. The present semiempirical state of our knowledge of the reflection of molecules from the surface of a solid is summarized and some directions for research are indicate d. The aerodynamic properties of bodies in highly rarefied flows is considered with emphasis on the long cylinder as a case of special interest. The theory is extrapolated to the limit of very h igh speed ratios or Mach numbers and the results are compared with those de duced from the Newtonian flow theory. The application of recent studies of rarefied gas flows to the development of instruments for the measurement of the pressure, temperature and density of such flows is reviewed in some detail. The use of free molecule probes for the study of boundary layers and shock waves is outline d. The review is brought to a close with a very brief consideration of some factors involved in the collision-free flow of a plasma.

The time response of a wind tunnel pressure measuring system, comprising a pressure transducer of fixed volume and a length of capillary tubing, is analysed and the results compared with experiments. It is shown that the approximate analysis of Kendall (1958), in which the friction losses at any given time are assumed equal to the steady state losses, has a wide range of validity, provided the L/R ratio for the capillary tube is large and the inlet and exit losses are included as equivalent lengths of the capillary tube. The College of Aeronautics was founded in 1946 and was granted university status in 1969 becoming the Cranfield Institute of Technology. In 1993 it changed its name to Cranfield University.

The fundamental problem of structural design is the deternaination of structures of minimum weight which safely equilibrate a given system of external forces. The classical theorem of Michell gave the basic requirements for such a structure. The first part of this paper analyses the geometrical layout of two-dimensional structures which satisfy these requirements, making use of the analogy with the theory of plane plastic flow. Expressions for the calculation of sizes and the total volume of the structural members are developed. Method of graphical construction of the structural layout is also given. In the second part, the analogy with a known solution of plastic flow is used to develop solutions for a cantilever under tip shear force and a beam under uniform bending moment. Comparisons with the conventional types of construction are made and the superiority of the Michell structures are demonstrated. The College of Aeronautics was founded in 1946 and was granted university status in 1969 becoming the Cranfield Institute of Technology. In 1993 it changed its name to Cranfield University.

The two-dimensional supersonic sail is analysed using Busemann's second-order theory. It is found to have a universal shape, which is part of a Sici spiral. Aerodynanaic characteristics are calculated for a few sails. The tension in sails flying at Mach numbers of 2 and 3 at altitudes of 20,000 and 70,000 feet is large and suggests that wire sails will be needed for flight under these conditions. The College of Aeronautics was founded in 1946 and was granted university status in 1969 becoming the Cranfield Institute of Technology. In 1993 it changed its name to Cranfield University.

The College of Aeronautics was founded in 1946 and was granted university status in 1969 becoming the Cranfield Institute of Technology. In 1993 it changed its name to Cranfield University.

The College of Aeronautics was founded in 1946 and was granted university status in 1969 becoming the Cranfield Institute of Technology. In 1993 it changed its name to Cranfield University.

The College of Aeronautics was founded in 1946 and was granted university status in 1969 becoming the Cranfield Institute of Technology. In 1993 it changed its name to Cranfield University.

The College of Aeronautics was founded in 1946 and was granted university status in 1969 becoming the Cranfield Institute of Technology. In 1993 it changed its name to Cranfield University.

The College of Aeronautics was founded in 1946 and was granted university status in 1969 becoming the Cranfield Institute of Technology. In 1993 it changed its name to Cranfield University.

The College of Aeronautics was founded in 1946 and was granted university status in 1969 becoming the Cranfield Institute of Technology. In 1993 it changed its name to Cranfield University.

The College of Aeronautics was founded in 1946 and was granted university status in 1969 becoming the Cranfield Institute of Technology. In 1993 it changed its name to Cranfield University.

The College of Aeronautics was founded in 1946 and was granted university status in 1969 becoming the Cranfield Institute of Technology. In 1993 it changed its name to Cranfield University.

The College of Aeronautics was founded in 1946 and was granted university status in 1969 becoming the Cranfield Institute of Technology. In 1993 it changed its name to Cranfield University.

The College of Aeronautics was founded in 1946 and was granted university status in 1969 becoming the Cranfield Institute of Technology. In 1993 it changed its name to Cranfield University.

The College of Aeronautics was founded in 1946 and was granted university status in 1969 becoming the Cranfield Institute of Technology. In 1993 it changed its name to Cranfield University.

The College of Aeronautics was founded in 1946 and was granted university status in 1969 becoming the Cranfield Institute of Technology. In 1993 it changed its name to Cranfield University.

The College of Aeronautics was founded in 1946 and was granted university status in 1969 becoming the Cranfield Institute of Technology. In 1993 it changed its name to Cranfield University.