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A Summary by Dr. Alexander Klemin of the Papers Presented Before the Fourteenth Meeting of the Institute held at Columbia University, New York, on January 29–31, 1946. AERODYNAMICS IN spite of increased wing loadings, the use of full span wing flaps has been delayed, because of inability to find a suitable aileron. The Development of a Lateral‐Control System for use with Large‐Span Flaps by I. L. Ashkenas (Northrop Aircraft), outlines the various steps in the aerodynamic development of a retractable aileron system well adapted to the full span flap and successfully employed on the Northrop P‐61. Included is a discussion of the basic data used, the design calculations made, and the effect of structural and mechanical considerations. Changes made as a result of preliminary flight tests are discussed and the final flight‐test results are presented. It is concluded that the use of this retractable aileron system has, in addition to the basic advantage of increased flap span, the following desirable control characteristics: (a) favourable yawing moments, (b) low wing‐torsional loads, (c) small pilot forces, even at high speed.

THE Funk Gerat 10 equipment is the latest standardized type, and is installed in all the later bombers and reconnaissance machines of the Luftwaffe.

This aircraft, or more exactly this integrated weapons system, is undoubtedly of major importance to both the British aircraft industry and the Royal Air Force. It is beyond question the most exacting project which the British industry has undertaken and as such has demanded adoption of the latest techniques, materials, equipment and management procedures as well as pursuit of research and development programmes on an unprecedented scale. In terms of air power, this system represents a substantial advance on any comparable aircraft or system currently in service and will give the Royal Air Force a strike and reconnaissance capability at high and low level which is possibly unmatched by any other air force in the world. The design philosophy of the TSR‐2 as it applies to an aircraft designed primarily for the high‐speed, low‐level strike/reconnaissance role was described in detail in the December 1963 issue of Aircraft Engineering (Ref. 1) but since that initial appraisal of the TSR‐2 was written some eleven months ago, there has been a gradual release of further information concerning the aircraft, its systems, power plant and equipment. It is the purpose of this article to bring the story up to date in that particular context, although it should be emphasized that the TSR‐2 is still subject to the strictest security embargo and it will be many years before a detailed study of the complete weapons system can be published. It is not intended to cover the same ground as the earlier article (Ref. 1) attempted but, before proceeding to detailed consideration of the systems, a brief overall description of the aircraft is given for the sake of completeness.

THE Twenty‐fourth S.B.A.C. Flying Display and Exhibition to be held at Farnborough during the week Monday,September 7, to Sunday, September 13, promises to be the most interesting ever held. This is in part due to the decision taken in 1962 not to hold an S.B.A.C. Show in the summer of 1963, and partly the result of the effort now being concentrated upon the Concord supersonic airliner project, the TSR‐2 supersonic strike and reconnaissance bomber, the Hawker Siddeley P. 1154 V/STOL fighter, two new research aircraft and a whole range of new transport aircraft. Apart from the models and displays which will be mounted by the major airframe and engine manufacturers demonstrating their own involvement with these projects and programmes, the stands of the Associate Members of the Society of British Aerospace Companies will abound with examples of materials, techniques and equipment which these companies are producing in support of the latest programmes—notably TSR.2 and Concord.

THE eleventh annual meeting of the Institute was for the first time held simultaneously in three centres—in New York City at Columbia University, in Detroit at Rackham Educational Memorial, and in Los Angeles at the University of Southern California—from January 25 to 29. The purpose of the three simultaneous meetings was to minimize travel by executives and engineers from important war jobs in the present emergency. The same programme was offered at all three centres, papers being sometimes presented by proxies—experts in the same field as far as possible. In spite of the fact that attendance was divided between three centres, there was splendid representation at each place and a wide range of subjects was covered in the many papers. Naturally these were restricted more to analysis, and technology and information as to the latest design or production features of current aircraft or engines was withheld. The same ban applied to striking developments in accessories, instruments and armaments. All papers had to be approved by the Army or Navy and to be read substantially as written. While off‐the‐record discussions were permitted, these discussions were not made public. In particular there was a ban on comparisons between foreign and American materials, equipment or methods. The formula for control of comparison performance stated that the manufacturer's smooth curve calibrations and performance figures might be quoted, but no Wright field performance figures or data could be revealed. In spite of such restrictions a tremendous amount of valuable technical information was presented to the assembled engineers.

Accles & Pollock Ltd. of Oldbury, Worcestershire, a TI Steel Tube Division company, will be exhibiting a comprehensive range of precision steel tube and tubular products, including plain, annularly convoluted and thin wall tube, at Farnborough.

The purpose of this paper is to outline a novel concept of radio altimeter CRW-13 that has been designed and developed in the Lukasiewicz Research Network – Institute of Aviation as a result of the need to update the outdated structure of RWL-750M.

The new design of the device consists of integral antennas and signal processor for smart digital signal filtering.

As a result of a number of laboratory tests and flight tests of the device installed on MP-02 “Czajka” ultralight aircraft promising results were achieved. They allow to move on to the next stage of implementation and preparation for the device certification.

The CRW-13 meets with great interest of civilian and military potential customers. It is an ideal solution for airplanes, helicopters, unmanned and guided missiles. The universal design enables installation on many different platforms where exact height measurement is needed and crucial.

At the origin of the new concept was the need to replace the separate transmitting and receiving antennas with one unit comprising two planar microstrip antennas placed directly next to each other on a common plate block in the transceiver. This solution eliminates thick antenna cables and coaxial connectors, which are the most unreliable and problematic elements of radio altimeters. The new concept of integral antennas and the use of signal processors for smart digital signal filtration made it possible to take the technology to the next level.

The pressure control valve is a possible means of overcoming the effects of compliance between a hydraulic servo and its load. The valve consists of two stages; an open‐centre flow control valve schematically analogous to a resistance bridge, and a split‐slider valve. In order to study the dynamics of the system it is convenient to set up an electrical analogue for the mechanical system. This will give the non‐linear equations of the system. Several forms of the various impedance elements making up the system require consideration. The resistance of a length of hydraulic line can be obtained from the friction factor and will depend on the flow regime which prevails. In developing an expression for the inductance of a length of line the assumption is made that the wavelength of the oscillatory motion is long compared with the line length. In considering the resistance of orifices it is necessary to take into account the three regimes for flow through an orifice, laminar, transition, and turbulent flow. The inductive effect of an orifice arises from the acceleration of the fluid as the streamlines converge through the orifice; an expression can be derived by applying Newton's second law of motion to the column of oil passing through the orifice. The effective capacitance of a volume can be derived by considering wave motion in one dimension. An expression for the radiation resistance of a piston is derived, and also one for the incident and reflected waves. In constructing the electrical analogue for the slider valve the mass and viscous damping of the slider as well as Bernoulli forces must be represented.

In order to maintain an aircraft or other moving craft on a direct course towards its destination despite any tendency to drift, it is steered automatically in accordance with a magnetic or gyroscopic compass associated with a directional antenna which receives radio‐frequency signals from any broadcasting station near the destination, the antenna being maintained at a constant angle to the earth's magnetic field. The polepicces 2 of an earth‐inductor compass are initially adjusted to give a zero current through the armature when the craft starts out on a set course, and a frame aerial 24 is set at the required angle, relative to the compass pole‐pieces, to lie in a plane at right‐angles to the direction of propagation of the radio‐frequency waves. The two are geared together, so as always to maintain this setting, by the worm gear 12, 13, gears 11, 59, differential gear 57, gears 58, 62 and worm gear 63; the initial relative setting being effected by turning a shaft 60, on which the planet pinion spindles of the differential gear are mounted, through gearing 68, 69 from an indicator 70. The gears 58, 59 are loose on the shaft 60 and are fixed to the two other pinions of the differential gear. The output from the armature of the compass is connected across a polarized relay 4 through a resistance 21 across which a voltage is introduced by a known gyroscopic device 11 to correct for the vertical component of the earth's magnetic field whenever the craft is turned. When the craft yaws the relay 4 is actuated to reduce the bias on one or other of the grids of two thermionic valves 5, 6, causing anode current to flow and energize one or other of two clutches 15, 16, whereby a shaft 14 is rotated in one or other direction by a continuously running motor 18. This shaft 14 is geared to the wheel 11 whereby the polepicces 2, and the frame aerial, are caused to follow up the yaw. A dial 77 indicates the position of the craft with respect to the north. Simultaneously a contact arm 51, which is a loose friction fit on its spindle, makes contact with one or other of two contacts 52, 53 to apply a voltage from one of two oppositely polarized batteries 55, 56 and a resistance 42 in a circuit including a polarized relay 41. This relay is similar to the relay 4 and acts through similar valves and gearing to rotate a gear 45 to actuate a rudder 37. The rudder is connected also to a pointer 47 moving over a potentiometer 48 in bridge formation with two resistances 50 whereby a voltage is fed back to the relay circuit tending to de‐energize it. The ends of the frame aerial winding are connected to the grid cathode circuit of a valve 26 which includes also a source 29 of low frequency oscillations. A non‐directional aerial 25 is connected to the grid of a valve 27. The plates of the two valves are in parallel and the combined amplified output is fed to a demodulator 28 connected to the primary 30 of a transformer 31. As long as the frame 24 is at right angles to the direction of the incoming waves no low frequency oscillation will appear at the winding 30, but should the craft drift or yaw off the course, oscillations appear which are fed in opposite phase to the grids of two valves 32, 33. A transformer 36 also transmits the oscillations from the device 29 to the two grids in the same phase. The anode currents of the two valves flow in opposite directions through the two halves of a resistance 34 and the valves are so biased that the two currents are equal. Consequently there is normally no potential difference between the two ends of the resistance 34 and no current flows through a resistance 43 across a portion of which the relay 41 is connected. Whenever modulations appear in the primary 30, however, the balance is upset and the relay 41 is actuated to energize the rudder mechanism. An instrument 73 shows the amount of deviation. Should there be no forces tending to cause the craft to drift it may be steered by the compass alone, in which case a switch 79 is moved to put the relay 41 into communication with the compass instead of the resistance 43, and a switch 80 is moved to cut out the relay 4.