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Lightning strike tests on model aircraft, as part of the Electrical Research Association's service to British industry, have provided data on which the safety of delta‐winged aircraft such as Concorde will be assessed.

The purpose of this paper is to design a stable controller such that the control input is applied to the delta-wing aircraft in order to adjust the roll dynamics. The controller must provide a desired tracking performance with minimum tracking error.

In this paper, the second level adaptation (SLA) strategy is applied to control a delta-wing aircraft using multiple models. The implemented control structure is compared with the first level adaptation (FLA) and model reference adaptive control (MRAC) techniques.

SLA architecture not only copes with a wide uncertainty domain caused by aerodynamic effects, but also its rapid and accurate convergence is one of its most important features. Furthermore, this strategy makes a smoother control signal with respect to FLA and MRAC even at the same initial times. It should be also noted that SLA using three models, copes with uncertainty that may occur to the aircraft at high Angle Of Attacks (AOAs) at the entire flight envelope.

In this paper for the first time the application of this strategy is used to identify and control a delta-wing aircraft. Furthermore a systematic block diagram approach is proposed for the design.

This study aims to investigate the effects of propeller locations on the aerodynamic characteristics of a generic 55° swept angle sharp-edged delta wing unmanned aerial vehicle (UAV) model.

A generic delta-winged UAV model has been designed and fabricated to investigate the aerodynamic properties of the model when the propeller is placed at three different locations. In this research, the propeller has been placed at three different positions on the wing, namely, front, middle and rear. The experiments were conducted in a closed-circuit low-speed wind tunnel at speeds of 20 and 25 m/s corresponding to 0.6 × 10⁶ and 0.8 × 10⁶ Reynolds numbers, respectively. The propeller speed was set at constant 6,000 RPM and the angles of attack were varied from 0° to 20° for all cases. During the experiment, two measurement techniques were used on the wing, which were the steady balance measurement and surface pressure measurement.

The results show that the locations of the propeller have significant influence on the lift, drag and pitching moment of the UAV. Another important observation obtained from this study is that the location of the propeller can affect the development of the vortex and vortex breakdown. The results also show that the propeller advance ratio can also influence the characteristics of the primary vortex developed on the wing. Another main observation was that the size of the primary vortex decreases if the propeller advance ratio is increased.

There are various forms of UAVs, one of them is in the delta-shaped planform. The data obtained from this experiment can be used to understand the aerodynamic properties and best propeller locations for the similar UAV aircrafts.

To the best of the author’s knowledge, the surface pressure data available for a non-slender delta-shaped UAV model is limited. The data presented in this paper would provide a better insight into the flow characteristics of generic delta winged UAV at three different propeller locations.

The goal of this research is to demonstrate micro‐electro‐mechanical systems (MEMS)‐based transducers for aircraft maneuvering. Research in wind tunnels have shown that micro‐actuators can be used to manipulate leading edge vortices found on aerodynamic surfaces with moderate to highly swept leading edges, such as a delta wing. This has been labeled as the MEMS vortex shift control (MEMS‐VSC). The work presented in this paper seeks to detail the evolution of real‐world flight tests of this research using remotely piloted vehicles (RPVs).

Four different RPVs were constructed and used for flight tests to demonstrate the ability of using MEMS devices to provide flight control, primarily in the rolling axis.

MEMS devices for high angle‐of‐attack (AOA) turning flights have been demonstrated and the paper finds that the success of a complex project like the MEMS‐VSC requires the marriage of basic science expertise found in academia and the technical expertise found in industry.

Owing to the need to test fly the RPVs at low altitudes for video documentation while performing high AOA maneuvers, the attrition of the RPVs becomes the dominant factor to the pace of research.

MEMS sensors and actuators can be used to augment flight control at high AOA, where conventional control surfaces typically experiences reduced effectiveness. Separately, the lessons learned from the integration efforts of this research provide a potentially near parallel case study to the development of ornithopter‐based micro aerial vehicles.

This is the only research‐to‐date involving the demonstration of the MEMS‐VSC on real‐world flight vehicles.

Recent technical developments in the field of hydrodynamic sustentation, resulting from the unique techniques associated with the free‐body testing of self‐propelled dynamically similar models, has resulted in a great resurgence of interest in the use of water‐based aircraft in the National Defence. This paper describes some of the more important aspects of this research and discusses possible trends in military water‐based aircraft development. In addition to the military applications of the new high‐speed hydrodynamic developments, consideration is given to the development of transonic water‐based transport designs. Since the days of the famous flying‐boat clippers, over‐ocean transport has all but succumbed to the faster landplane. It is shown that an all‐jet water‐based transport, incorporating unusual safety and performance, is now a practical and logical development.

An aircraft powered by a gas‐turbine jet‐propulsion engine, the exhaust gases from which are discharged rearwardly through a jet pipe as a propulsive jet stream for normal forward flight, is provided with a fan mounted with its axis vertical, the fan drawing in air from atmosphere and discharging an air stream downwardly so as to produce an upward component of thrust on the aircraft, and means operable at will for diverting the exhaust gases from the jet pipe to drive the fan. The delta‐wing aircraft shown in FIG. 1 is powered by a gas‐turbine jet‐propulsion engine 3 which discharges exhaust gases as a propulsive jet stream through a jet pipe 5. An intermediate pipe 5a between the engine and the jet pipe is connected with two branch pipes 7 and is provided with a valve (not shown) which allows any desired proportion of the exhaust gases to be diverted into the branch pipes. The aircraft is provided with two fans, one in each wing, which rotate in opposite directions to balance out gyroscopic effects. As shown in FIG. 2, each fan rotor 12 comprises rotor blades 12b, a shroud ring 12c connecting the tips of the rotor blades, and a row of axial flow turbine rotor blades 12dmounted on the outer surface of the shroud ring. Exhaust gases diverted through the hand pipes 7 are supplied to these turbine rotor blades through a turbine inlet volute 13 which has a downwardly facing outlet provided with turbine nozzle vanes 14 co‐operating with the turbine rotor blades 12d. Rows of stator blades 19, 20 are provided above and below the fan rotor blades 12b, and these blades may be adjustable to enable the vertical lift to be varied; the pitch of the fan rotor blades may also be variable. Control of the aircraft may be effected by differential control of the blading of the two fans; alternatively or in addition the turbine nozzle vanes 14 may be adjustable. The inlets and outlets of the fans may communicate with the atmosphere through apertures in the wings which may be opened or closed by pivoted vanes 21, 22 which may be operated differentially to control the aircraft. Alternatively the inlets may be connected to one or more boundary layer suction openings in the surface of the aircraft. Additional fans 23, 24 may be mounted in the wing tips and nose of the aircraft to control the aircraft, these fans being driven by compressed air bled off from the compressor of the engine 3.

Development of the Lockheed supersonic transport has followed the basic philosophy that an advance in air travel in terms of speed and economics should be accompanied by similar advances in aeroplane safety and flying qualities. To achieve these objectives, Lockheed's SST design work has been concentrated for many years on the development of a fixed‐wing design. The present configuration—called a double delta—provides a simple high lift system with low wing loading, excellent low speed stability and control, and large favourable ground effects in landing, with inherent advances in operational simplicity and safety.

THE efficient design and construction of the latest types of Swedish military aircraft, with wings with high critical Mach numbers, has necessitated a thorough investigation into the structural behaviour of swept and delta wings of both the thin and thick types. It is the main purpose of this paper to present some important test results and pertinent details of some of the small scale models which have been built to supplement the theoretical estimation of the stress distribution and deflexion patterns. In some cases these models have also been constructed to provide information on certain unusual structural configurations, which would have otherwise taken many months to obtain by using approximate theoretical methods. The stress distributions for each model are illustrated in such a way that comparison between the different types of structures may readily be made.

ALTHOUGH the first formal specification for the TSR.2 was formulated in the shape of General Operational Requirement 339, in 1956, the industry and the Royal Air Force had for some time previously been ‘sketching’ the outlines for a Canberra replacement. The English Electric Canberra was designed to specification B.3/45 as a high‐altitude medium bomber and, since its conception, has been produced and operated in a wide range of roles; including bomber, photographic reconnaissance, trainer, night interdictor, and target drone.

MUCH has been written about possible developments in the next decade, but any forecasting must of necessity be conjectural. As far as the next generation of military aircraft is concerned the situation is very obscure, except for the fact that it is known that fewer types will be required. Developments in the civil field are rather easier to foresee, these being based on the anticipated travelling habits of the world's population.