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Research in aircraft structures is constantly bringing forward new problems of a fundamental character. Many of these respond to systematic experiment, and the paper presents the experimental approach in terms of recent work done in Great Britain and particularly at the Royal Aircraft Establishment. One aspect of research considered is the testing of small specimens made of xylonite. Another is the strength testing of actual aircraft, which opens up several fields of research activity for discussion. Design studies of new testing equipment for large aircraft and for pressure cabins are also described. Consideration is given to the measurement of external forces in flight and the design of measuring instruments, including a description of the new counting accelerometer recently developed by the R.A.E. Finally, structural fatigue is discussed as being one of the most difficult subjects with which the structural specialist has yet had to deal.

This paper aims to deal with the experimental estimation of both longitudinal- and lateral-directional aerodynamic characteristics of a new twin-engine, 11-seat commuter aircraft.

Wind tunnel tests have been conducted on a 1:8.75 scaled model. A modular model (fuselage, wing, nacelle, winglet and tail planes) has been built to analyze both complete aircraft aerodynamic characteristics and mutual effects among components. The model has been also equipped with trailing edge flaps, elevator and rudder control surfaces.

Longitudinal tests have shown the goodness of the aircraft design in terms of aircraft stability, control and trim capabilities at typical clean, take-off and landing conditions. The effects of fuselage, nacelles and winglets on lift, pitching moment and drag coefficients have been investigated. Lateral-directional stability and control characteristics of the complete aircraft and several aircraft component combinations have been tested to estimate the aircraft components’ interactions.

The experimental tests have been performed at a Reynolds number of about 0.6e6, whereas the free-flight Reynolds number range should be between 4.5e6 and 9.5e6. Thus, all the measured data suffer from the Reynolds number scaling effect.

The study provides useful aerodynamic database for P2012 Traveller commuter aircraft.

The paper deals with the experimental investigation of a new general aviation 11-seat commuter aircraft being brought to market by Tecnam Aircraft Industries and it brings some material on applied industrial design in the open literature.

The intention of this paper is to compare the performance of five Chipmunk aircraft, and to investigate the assumption that the performance of any operational aircraft can be considered to be representative of that type of aircraft. All the aircraft were tested, with the same instrument panel fitted, and were weighed in order to determine the variation in weight and centre of gravity. Flight tests were then conducted to investigate the following aspects of performance: turning, climbing, drag, engine power, stalling and spinning. The results, reduced from the readings taken during flight tests, showed that there are two main causes of variation between the performances of the aircraft. First the age and condition of the engine were seen to affect the power dependent aspects of performance. Secondly there was a wide variation of profile drag which was probably due to distortion of the airframes.

IN the year 1945 aircraft structural design had reached an advanced stage in this country, as judged by all previous standards. The needs of war and the vast expenditure on aircraft design and manufacture had unquestionably forced the pace of progress. On the other hand, war‐time conditions must inevitably have tended to produce an unbalanced growth. Expenditure of money and effort was accompanied by a no less drastic expenditure of technical capital, and really long‐term thinking was unavoidably put aside.

To provide a general review of the flight flutter test techniques utilized in aeroelastic stability flight testing of aircraft, and to highlight the key items involved in flight flutter testing of aircraft, by emphasizing all the main information processed during the flutter stability verification based on flight test data.

Flight flutter test requirements are first reviewed by referencing the relevant civil and military specifications. Excitation systems utilized in flight flutter testing are overviewed by stating the relative advantages and disadvantages of each technique. Flight test procedures followed in a typical flutter flight testing is described for different air speed regimes. Modal estimation methods, both in frequency and time domain, used in flutter prediction are surveyed. Most common flight flutter prediction methods are reviewed. Finally, key considerations for successful flight flutter testing are noted by referencing the related literature.

Online, real time monitoring of flutter stability during flight testing is very crucial, if the flutter character is not known a priori. Techniques such as modal filtering can be used to uncouple response measurements to produce simplified single degree of freedom responses, which could then be analyzed with less sophisticated algorithms that are more able to run in real time. Frequency domain subspace identification methods combined with time‐frequency multiscale wavelet techniques are considered as the most promising modal estimation algorithms to be used in flight flutter testing.

This study gives concise but relevant information on the flight flutter stability verification of aircraft to the practicing engineer. The three important steps used in flight flutter testing; structural excitation, structural response measurement and stability prediction are introduced by presenting different techniques for each of the three important steps. Emphasis has been given to the practical advantages and disadvantages of each technique.

This paper offers a brief practical guide to all key items involved in flight flutter stability verification of aircraft.

Engineered material arresting systems (EMASs) are dedicated to stopping aircraft that overrun the runway before they enter dangerous terrain. The system consists of low-strength foamed concretes. The core component of the arresting system design is a reliable simulation model. Aircraft test verification is required before the practical application of the model. This study aims to propose a simulation model for the arresting system design and conducts serial verification tests.

Six verification tests were conducted using a Boeing 737 aircraft. The aircraft was equipped with an extra inertia navigation system and a strain gauge system to measure its motion and the forces exerted on the landing gears. The heights of the arrestor beds for these tests were either 240 or 310 mm, and the entering speeds of the aircraft ranged from 23.9 to 60.6 knots.

Test results revealed that both the aircraft and the pilots on board were safe after the tests. The maximum transient acceleration experienced by the dummies on board was 2.5 g, which is within the human tolerance. The model exhibited a satisfied accuracy to the field tests, as the calculation errors of the stopping distances were no greater than 7 per cent.

This study proposes a simulation model for the arresting system design and conducts serial verification tests. The model can be used in EMAS design.

This is our report on this first international assembly of Aircraft Maintenance and Engineering, held in Zurich 6th–9th February 1979. This was AIRMEC 79 — and, as was foreseen in our Comment in the January issue, the significance of this innovation among aviation occasions was taken up by thirty‐six countries who sent 276 delegates to the convention, which was supported by the Exhibition, attracting 112 exhibitors from 17 countries. There is every chance that this event will take its place with Farnborough, Paris and Cranfield as a regular feature of the aviation scene and of considerable interest to all engaged in aircraft maintenance. The organisers did announce at the end of that Show that AIRMEC 81 would take place, again in Zurich, in February of that year. And perhaps it is interesting to comment at this stage about the decision to return to Zurich. While it might be said that the event was a success, the fact that the convention was held in a venue separate from the Exhibition, did have some disadvantages and the consensus among the exhibitors was that this did discourage many of the 2260 in attendance from really taking in the Exhibition. Perhaps the only exception to this were the Chinese whose delegation spent almost all of every day in the Exhibition halls, visiting every stand and spending considerable time at each one.

As part of the V.10 F programme financed by Service Technique de la Production Aeronautique (STPA), AEROSPATIALE and DASSAULT — BREGUET have joined forces to produce a single Falcon 10 wing entirely made of carbon fibre. This wing has just been sent from the AEROSPATIALE Company's Nantes factory to the Toulouse Aernautic Testing Centre. A second wing will also be built, but this time, by DASSAULT‐BREGUET Biarritz plant. The two wings will be used for static fatigue testing. The programme calls for another pair of wings, one to be made by each of the same firms. They will later be mounted to a Falcon 10 for flight testing.

The XH‐59A ABC™ demonstrator aircraft is a research vehicle designed to investigate the unique characteristics of the Advanced Blade Concept. The aircraft, shown in Fig. 1, has now completed an extensive flight test programme investigating its full airspeed, altitude, and manoeuvring envelope. Aircraft design was initiated in 1972, with first flight in July 1973, with certain interruptions to review and analyse flight data and make modifications to the aircraft. The culmination of the flight test programme was a 12.7 hour evaluation of the aircraft by the US Army Aviation Development and Test Activity at Ft. Rucker, Alabama. This evaluation is the subject of this technical report. Reference 1 is the Army report documenting their evaluation. The XH‐59A programme has been jointly funded by the US Army, Navy and Air Force, the National Aeronautics and Space Administration, and Sikorsky Aircraft. The majority of funding has come from the Army.

This paper aims to provide a detailed review of the experimental research on the prediction of aircraft spin and recovery characteristics using dynamically scaled aircraft models.

The paper organizes experimental techniques to predict aircraft spin and recovery characteristics into three broad categories: dynamic free-flight tests, dynamic force tests and a relatively novel technique called wind tunnel based virtual flight testing.

After a thorough review, usefulness, limitations and open problems in the presented techniques are highlighted to provide a useful reference to researchers. The area of application of each technique within the research scope of aircraft spin is also presented.

Previous reviews on the prediction of aircraft spin and recovery characteristics were published many years ago and also have confined scope as they address particular spin technologies. This paper attempts to provide a comprehensive review on the subject and fill the information void regarding the state of the art aircraft spin technologies.