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Early aircraft engines were usually bolted direct to the aircraft structure and no attempt was made to prevent the vibrations which they set up from being transmitted to the airframe. With increasing engine powers and the use of larger airscrews these vibrations eventually become of sufficient magnitude in some cases to cause annoyance to the occupants of the aircraft and also failure by fatigue of parts of the structure. Various attempts were made both to analyse the source of the vibrations with a view to eliminating them or reducing them to an acceptable magnitude. Where this was not possible attempts were made to isolate the disturbances from the airframe and its occupants. This paper presents the basic theory of vibration isolation and gives an account of the various sources of vibration met with in reciprocating, turbo‐propeller and pure‐jet installations. The loads acting on the engine during various conditions of flight are then examined as a knowledge of these is required in order to determine the strength of the supporting units. Various practical engine mounting configurations are then considered which will give vibration isolation together with adequate support of the engine under all conditions of flight. Some account is given of the properties of rubber and the design and testing of rubber vibration isolators, and some installation problems are examined. Finally, the complete programme of testing an installation both on the test‐bed and inflight to evaluate the degree of vibration isolation achieved is described, together with various criteria of acceptability both from a structural and physiological standpoint. A bibliography covering the various sections is included.

This paper aims to present the analysis of introduction of single engine turbo-prop aeroplane class in terms of certification specifications and flight crew licensing regulations.

Following the results of flight testing and additional performance and sizing calculations, the proposed class was placed among the existing aeroplane taxonomy in terms of performance, flight loads, mass penalty, fuel economy and several other factors. Concerning small air transport initiative, the new class was tried to be placed as a starting point in commercial pilot career.

The paper points the potential market for single engine turbopropeller aeroplanes and lists today obstacles in wider introduction. Therefore, remarks about required change of regulations and requirements for design process, as well as for crew licensing, are underlined.

The results of the study would be helpful in preliminary design of a new low-power turboprop aeroplane, as well as during tailoring the certification specifications.

The approach presented in this paper is a detailed extension of an original idea presented by author for the first time during Clean Sky/small air transport workshop.

Aeronautical research scientists of the National Advisory Committee for Aeronautics have in the last six years indexed 7,070 non‐security classified NACA research reports under 458 different subject classification headings for a total of 18,619 subject entries. They further face the task of subject classifying over 400 similar research reports per year, plus the large number of security classified reports issued annually.

Europe has adopted Flight Path 2050 (FP 2050) challenge with an objective of 90 per cent of the travelers being able to reach door-to-door European destinations within 4 hours by 2050. The aim can be achieved by reliable, well-organized small aircraft transport (SAT). Analysis of the currently operating small aircraft operational reliability data will support the development of future aircraft designs as well as reliability and safety requirements necessary for commercial operations.

The paper provides results of a statistical analysis of small aircraft current operations based on the reported events contained in the Database named European Coordination Centre for Aviation Incident Reporting Systems database. It presents identified safety indicators and focuses particularly on those related to the aviation technology.

It has been found that certain airframe and powerplant systems have the biggest influence on flight safety.

Multidisciplinary analysis of the operational and aircraft components reliability data will help in a proper preparation of the SAT supporting facilities, a design process of new aircraft and improvements of the existing airframe and powerplant systems.

Presented results are valuable for further developments of the statistical tools facilitating new product introduction.

The purpose of this paper is to present study of thermal creep stresses and strain rates in a circular disc with shaft having variable density by using Seth’s transition theory.

Seth’s transition theory is applied to the problem of thermal creep transition stresses and strain rates in a thin rotating disc with shaft having variable density by finite deformation. Neither the yield criterion nor the associated flow rule is assumed here. The results obtained here are applicable to compressible materials. If the additional condition of incompressibility is imposed, then the expression for stresses corresponds to those arising from Tresca yield condition.

Thermal effect increased value of radial stress at the internal surface of the rotating disc made of incompressible material as compared to tangential stress and this value of radial stress further much increases with the increase in angular speed as compared to without thermal effect. Strain rates have maximum values at the internal surface for compressible material.

The model proposed in this paper is used in mechanical and electronic devices. They have extensive practical engineering application such as in steam and gas turbines, turbo generators, flywheel of internal combustion engines, turbojet engines, reciprocating engines, centrifugal compressors and brake disks.

The following are the main points of interest to our readers from some of the papers presented at the Institute of Petroleum Summer Meeting at Llandudno last month.

The purpose of this paper is to describe studies of accidental ignition of fuel‐air mixture. Studies were carried out in a laboratory that contains the naturally aspirated aircraft engine LYCOMNIG 320B1A IO type used in the EM‐11C Orka aircraft and the intake system to determine its resilience to the effects of accidental ignition and the occurrence of a backfire.

Tests were performed on a model under extreme conditions (with the intake system closed) and under conditions similar to normal operation using fuels of different combustion rates.

It was found that the positive pressure caused by such accidental ignition under normal operating conditions did not exceed 0.08 bar and did not pose any hazard of damaging the intake system of the IO‐320B1‐type LYCOMNIG naturally aspirated aircraft engine, as designed by the aircraft manufacturer.

The positive results of the tests of the EM11C Orka aircraft intake system's resistance to flashback and other positive test results for this aircraft have contributed to obtaining the EASA.A.115 Certificate and the EASA.21J.117 Certificate for the Design Unit, and the plane was presented at the AERO – Friedrichshafen 2011 Exhibition.

The paper described how, in the laboratory, simulated extreme operating conditions of the naturally aspirated aircraft engine intake system powered aircraft fuels with different burning speeds (aviation gasoline, hydrogen).

The importance of effective laboratory work in mechanical engineering courses cannot be over‐emphasised. Firstly, laboratory work normally occupies about one third of the time in undergraduate and Higher National Certificate courses. Secondly, the laboratory building, experimental equipment and the time spent by academic staff and technicians in laboratory classes results in a substantial financial commitment. The need to spend this time and money wisely suggests a continuing demand for critical appraisal of the aims and practice of laboratory work. Further, there is a need to examine the design and layout of the laboratories themselves, and some literature has appeared in this field.

A series of articles dealing, in as simple a way as possible, with the basic facts of lubrication, lubricants, their selection and prescription, specification, application, and testing. This series is primarily intended for students, engineering personnel who may be unfamiliar with certain aspects and others who, one way or another, are interested in this important subject.

Although many large systems have by‐passed the problem by employing ‘natural language’, compound words remain a difficulty in thesaurus construction. In the past, rules have been devised which attempted to approach the problem via syntax, but these were not altogether satisfactory. Instead, it is proposed that the major criteria for handling compound words should rest upon their orthography (i.e. physical form), lexicography (dictionary definition) and semantics, with special attention being given to the possible occurrence of homographs—words which differ in meaning, but share a common form. The suggestions contained in BS 5723, Guidelines for the establishment and development of monolingual thesauri, are assessed in relation to these criteria. BS 5723 is criticized for failing to pay sufficient attention to the requirements of mechanized systems, and for its partial failure in not recording the divergent needs of pre‐and post‐coordinate systems.