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The purpose of the work is to carry out analysis of the possibilities and estimation of electric drive efficiency for rotors of helicopter propulsion systems (PS).

Methodology and comprehensive multidisciplinary technology for efficiency estimation of conventional and unconventional architectures PS on rotorcraft system level at preliminary design phase were developed.

Application of the approach allow to carry out analysis of hybrid (based on gas turbine and piston engines) and full electrical PS for superlight-, light- and medium-size helicopters.

It was shown what level of electrical technologies improvement may provide positive effect of the using of hybrid and full electrical helicopter PS of different architectures.

Close matching of helicopter and engine design and calculation aspects, as well as possibilities to use the external (experimental) performances of engine components, whole PS and helicopter aerodynamic performance, are the distinctive features of proposed technology and methodology.

This paper aims to argue for a China transmuting to fast overtake USA in innovation based on the extrapolation of past statistical trend. Case studies in self and co-innovation are provided so that the documentation of the dynamics of knowledge flows and a brain-linguistic explanation is given as to why, in the future, the Chinese are likely to lead in innovation.

This paper illustrates a multi-method approach in research for Chinese Management Studies. First, the sociological background of China is highlighted (Mao Zedong’s aphorism). Second, insights from OECD patent database are utilized. Third, the use of comparative research and development case-studies: self-innovation (Chinese) and co-innovation (contrasting Japanese versus French cooperation with Chinese). Fourth, is the inter-disciplinarily approach wherein the assimilating of knowledge is related to recent advances in brain research. Fifth, emphasizing the different levels in organizing for innovation: national (China), organizational (SOE), group processes and person-to-person, synapses within individual brains.

Statistical trend suggests that China is transforming and is on the path toward overtaking the USA in innovation. When will this happen? Using extrapolation as an indication, China may surpass the USA by the 50 per cent mark within the next decade. Insights into the processes of self-innovation and co-innovation are provided. Authors argue for a brain-linguistic explanation (Hebb, 1949) for further understanding why China will eventually lead ceteris paribus innovation, a function of the human brain.

This paper highlights on the basis of statistical trends (using OECD database) a rising, innovative China that is poised to overtake the USA in the near future. A major contribution is in providing insights of interactional processes required to foster innovation: self and co-innovation (comparing Japanese and French). The critical brain-linguistic role as the rationale as to why the Chinese are given a greater, more developed brain power that will eventually surpass the West in innovation.

The purpose of this paper is to explore how China’s manufacturers catch up with the forerunners through R&D cooperation by developing a new mode of latecomer–forerunner R&D cooperation, i.e. the periphery–core mode, which provides a viable way for China’s manufacturers to obtain forerunners’ core knowledge from their periphery knowledge via knowledge spillover and knowledge transfer.

The paper first reviews the literature on R&D cooperation process in the catching-up context and knowledge management in R&D cooperation. Then, three cases of R&D cooperation between China’s advanced technology manufacturers and their forerunners are introduced, with emphasis on interactivities in R&D cooperation and knowledge spillover. On the basis of the multi-case study, the periphery–core mode of R&D cooperation between latecomers and forerunners is conducted.

The paper finds that the latecomers can catch up with their forerunners by acquiring forerunners’ core technology used in periphery R&D activities. Through formal and informal interactions, the forerunners’ core technology can be extracted and transferred to latecomers, which the latecomers can then absorb and further develop. Thus, it can be concluded that the periphery–core mode of R&D cooperation is a viable way for the latecomers to get access to forerunners’ core technology.

The paper contributes to the literature on the catching-up theory by developing the periphery–core mode as a new mode for the latecomers to catch up with the forerunners. It expands the understanding of the latecomer–forerunner R&D cooperation by focusing on the way that China’s manufacturers as latecomers catch up with the forerunners by accessing the forerunners’ core knowledge from their R&D cooperation in periphery knowledge. The paper shows the mechanism of knowledge transfer and spillover in R&D cooperation. The role of communications, especially informal communication between cooperation partners, is emphasized in this process. This study also provides a new perspective for cooperation partner selection by arguing that latecomers can choose their cooperation partners according to the periphery and core knowledge they possess, other than the relationship between them. Besides, this paper emphasizes the mutual support between knowledge transfer, knowledge spillover and knowledge absorption, which is necessary for latecomers to achieve successful catching up in periphery–core R&D cooperation.

Chinook Accident ON the return flight to Sumburgh from Brent Field a Boeing Vertol 234 LR (Chinook) was only some four miles from the airport when the crew remarked on a noticeable increase in the noise level on the flight deck. One of them described it as a roaring noise. This was followed by a ‘bang’ and the aircraft pitched nose up to a near vertical attitude, went out of control and crashed into the water. Two survivors out of the total of three crew and 44 passengers were rescued and an intensive air and sea search involving Service and civilian aircraft and vessels failed to find any more survivors. Search and recovery operations continued ad some four days after the crash, about 75% of the fuselage and 95% of the transmission had been recovered.

THE purpose of this paper is to examine the part that metal fatigue plays in the engineering of the helicopter, and to outline the methods used at present to estimate the safe fatigue life of the component parts of the helicopter.

The purpose of this paper is to suggest new method for improving the condition indicators (CIs) used in health and usage monitoring system based on signal separation of gears.

The research method is based on employing signal separation techniques to improve gears signal and fault signature. The signal separation is based on adaptive filters concept.

CIs estimated for the deterministic part of vibration signal show higher sensitivity to gears faults in comparison to indicators estimated based on the original signal. This method proposed could enhance early fault detection in gears, particularly for those applications where strong background noise from other sources in the machine masks the characteristics fault components.

The contribution of this research is improving the CIs currently used for helicopter gearboxes. As consequence the safe operation and availability will be improved.

Froude Engineering has completed the installation and commissioning of an advanced helicopter transmission test rig at Westland Helicopters Ltd., Yeovil, which is unique in Britain. The contract worth £2m. to Froude Engineering, the Worcester‐based member of the Redman Heenan International group of companies, represents more than two years of work which began with a feasibility study of more precise and more reliable methods for testing complete helicopter transmissions as well as their components.

ATTENTION has been focussed on aspects of helicopter airworthiness by the publication of the HARP Report. In this document, existing requirements for public transport helicopters were reviewed and recommendations made for improved safety standards and it has been stated that a series of accidents in recent years, some of them related to North Sea operations, are believed to be reason for the request to the ARB which led to the setting up of the Panel. A contributory factor was the realisation that these kind of public transport operations were in their infancy and enormous expansion can be expected.

OVER THE PAST TWENTY YEARS the speed of helicopters has almost doubled whilst the payload carried per pound of helicopter weight has increased more than four times. Thus the productivity of the helicopter per lb of vehicle has increased eight‐fold.

ONE of the most significant influences of the past decade as far as rotating wing aircraft are concerned, was the 1984 report of the Helicopter Airworthiness Review Panel (HARP). The need for such a review arose out of concern over a number of accidents in the early 1980's and the report found that helicopters are five times less safe than public transport aircraft, compared on an hourly basis. When risks per flight are compared, this difference is about halved but even so, the accident rates are significantly worse than for modern jet transports. HARP found that the percentage of accidents due to air‐worthiness causes is higher on helicopters than on fixed wing aircraft, and also, that the percentage of accidents from airworthiness causes which prove fatal, is also appreciably higher on helicopters.