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Reports on a recent review of service experience relating to health and usage monitoring of rotorcraft transmission systems. Describes trials of integrated HUMS on military helicopters and an operator's experience using EuroHUMS on Super Puma helicopters. Informs on the vibration monitoring role of integrated HUMS. Notes the values of usage monitoring as distinct from health monitoring.

The purpose of this paper is to present the synthesis of a robust controller for autonomous small‐scale helicopter hovering control using extended H_∞ loop shaping design techniques.

This work presents the development of a robust controller for smooth hovering operation required for many autonomous helicopter operations using H_∞ loop shaping technique incorporating the Vinnicombe‐gap (v‐gap) metric for validation of robustness to uncertainties due to parameter variation in the system model. Simulation study was conducted to evaluate the performance of the designed controller for robust stability to uncertainty, disturbance rejection, and time‐domain response in line with ADS‐33E level 1 requirements.

The proposed techniques for a robust controller exhibit an effective performance for both nominal plant and 20 percent variation in the nominal parameters in terms of robustness to uncertainty, disturbance wind gust attenuation up to 95 percent, and transient performance in compliance with ADS‐33E level 1 specifications.

The controller is limited to hovering and low‐speed flight envelope.

This is expected to provide efficient hovering/low‐speed autonomous helicopter flight control required in many civilian unmanned aerial vehicles applications. Also, the technique can be used to simplify the number of robust gain‐scheduled linear controllers required for wide‐envelope flight.

The research will facilitate the deployment of low cost, small‐scale autonomous helicopters in various civilian applications.

The research addresses the challenges of parametric variation inherent in helicopter hovering/low‐speed control using an extended H_∞ loop shaping technique with v‐gap metric.

VERTICAL take‐off aircraft in the form of jump‐autogyros and helicopters have been under sporadic development since the first world war during which a co‐axial design attributed to von Karman was used tethered for observation purposes. Only limited success was achieved between the wars due to two main factors:

Reviews recent advances in rotorcraft technology as presented at a recent Royal Aeronautical Society conference on innovation in rotorcraft technology and the 1997 Paris Air Show. Reports research initiatives to improve key rotorcraft technologies in the areas of obstacle detection, vibration and noise reduction and smart structures. Also mentions advances in overcoming rotorcraft speed limitations through use of tiltrotor and tiltwing aircraft.

TO say that the Twenty‐fourth S.B.A.C. Show was an unqualified success is perhaps to gild the lily. True there were disappointments— the delay which kept the TSR‐2 on the ground until well after the Show being one—but on the whole the British industry was well pleased with Farnborough week and if future sales could be related to the number of visitors then the order books would be full for many years to come. The total attendance at the Show was well over 400,000—this figure including just under 300,000 members of the public who paid to enter on the last three days of the Show. Those who argued in favour of allowing a two‐year interval between the 1962 Show and this one seem to be fully vindicated, for these attendance figures are an all‐time record. This augurs well for the future for it would appear that potential customers from overseas are still anxious to attend the Farnborough Show, while the public attendance figures indicate that Britain is still air‐minded to a very healthy degree. It is difficult to pick out any one feature or even one aircraft as being really outstanding at Farnborough, but certainly the range of rear‐engined civil jets (HS. 125, BAC One‐Eleven, Trident and VCIQ) served as a re‐minder that British aeronautical engineering prowess is without parallel, while the number of rotorcraft to be seen in the flying display empha‐sized the growing importance of the helicopter in both civil and military operations. As far as the value of Farnborough is concerned, it is certainly a most useful shop window for British aerospace products, and if few new orders are actually received at Farnborough, a very large number are announced— as our ’Orders and Contracts' column on page 332 bears witness. It is not possible to cover every exhibit displayed at the Farnborough Show but the following report describes a wide cross‐section beginning with the exhibits of the major airframe and engine companies.

IN the September, 1956, issue of AIRCRAFT ENGINEERING, Mr McClements and Sq./Ldr. Armitagc surveyed ‘Helicopter Developments during the Post‐War Years’. The purpose of the present article is to discuss the subsequent developments which have taken place during the last six years. This period has been one of continued expansion in helicopter development and of much more widespread utilization of helicopters in both military and commercial operation. Since their initial development, over 150 different types of helicopter have been successfully flown. This figure includes many experimental machines or prototypes built by small groups. The major helicopter constructors have put about 40 types into quantity production and over 10,000 helicopters have been built in the Western countries. These have been predominantly for the military services, the large majority being built in U.S.A., but something approaching 2,000 have been used in commercial operations.

An adaptable, integrated full glass cockpit and flight management system has been developed and is in production for application in multiple Sikorsky rotorcraft. The entire system was conceived, designed, tested and delivered in an unusually short time period. A systematic process was used to define the avionics system attributes, major capabilities, and cost targets up‐front and track them during the development program. First flight was achieved 12 months after contract start, and production deliveries commenced 5 months after first flight. The integrated glass cockpit has accumulated more than 9,000 flight hours in customer operations to date. This flexible system architecture allowed the team of Sikorsky and Rockwell Collins to reuse several blocks of existing military and civil application software, and to interface the various Avionics subsystems using industry standards. This proved to be a critical factor in allowing us to meet the compressed design and development schedule.

Presents shortened versions of a number of papers presented at the recent 22nd European Rotorcraft Forum held in Brighton, UK, whose theme was advances in research, development, design, manufacturing, testing and operation. Specific aircraft focused on are the EH 101 Merlin trials aircraft; the V‐22 Osprey tiltrotor; and the NH 90 helicopter. Discusses some of the developments on the more general subjects that were dealt with at the symposium: advanced transmission technology; metallic structures; composites; and aeroelasticity.

The purpose of this paper is to discuss published research in rotorcraft which has taken place in India during the last ten years. The helicopter research is divided into the following parts: health monitoring, smart rotor, design optimization, control, helicopter rotor dynamics, active control of structural response (ACSR) and helicopter design and development. Aspects of health monitoring and smart rotor are discussed in detail. Further work needed and areas for international collaboration are pointed out.

The archival journal papers on helicopter engineering published from India are obtained from databases and are studied and discussed. The contribution of the basic research to the state‐of‐the‐art in helicopter engineering science is brought out.

It is found that strong research capabilities have developed in rotor system health and usage monitoring, rotor blade design optimization, ACSR, composite rotor blades and smart rotor development. Furthermore, rotorcraft modeling and analysis aspects are highly developed with considerable manpower available and being generated in these areas.

Two helicopter projects leading to the “advanced light helicopter” and “light combat helicopter” have been completed by Hindustan Aeronautics Ltd These helicopter programs have benefited from the basic research and also provide platforms for further basic research and deeper industry academic collaborations. The development of well‐trained helicopter engineers is also attractive for international helicopter design and manufacturing companies. The basic research done needs to be further developed for practical and commercial applications.

This is the first comprehensive research on rotorcraft research in India, an important emerging market, manufacturing and sourcing destination for the industry.