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The paper aims to detail the educational flight testing activities performed at the Department of Aerospace Science and Technology at the Politecnico di Milano (DSTA-PoliMi), including the development of low-cost, reliable flight testing instrumentation (FTI) and the administration of the graduate course in flight testing.

The flight testing course program closely adheres to the typical content of an introductory course offered in a professional flight testing school. However, within academic courses, it has a unique feature: each student is required to plan, perform and report on a real flight test experience, acting as a flight test engineer. Educational activities in this framework have been successfully matched to applied research and technical support for private companies.

At the educational level, several elements arise that are rarely concentrated within a single course, such as multidisciplinary integration, individual conceive-design-implement-operate (CDIO) project, real-life experimental procedures and techniques, teamwork, communication and reporting, relation with non-academic partners.

Based on the development of a FTI system for light aviation and on the flight testing course, DSTA-PoliMi has built a solid capability in flight testing, introducing graduate students to this specific niche of expertise and empowering co-operation with companies in the light aviation environment, while offering capabilities and tools that are typically regarded as a prerogative of major aerospace companies.

The paper discusses an original approach to flight testing education in an academic setting that avoids the high costs and complexity connected to certified aircraft flight operations and instrumentation, nevertheless allowing the achievement of significant results, also in applied engineering research.

GYROSCOPES are widely used in flight test instrumentation for measurement of angular rate of rotation.

IN 1955 Hamburger Flugzeugbau began to reconstruct its Finkenwerder plant and develop its aeronautical activities, following the period of in‐activity after the Second World War. Production began with an order from the West German Federal Defence Ministry for components for the S.N.C.A.N. 2501 Noratlas built under licence for the West German Air Force. Final assembly and flight testing of this twin‐engined transport were also carried out at Finkenwerder. The next stage of development involved participation in the European licence production of the Lockheed F.104G Starfighter, and in the design and construction of the Franco‐German C.160 Transall transport. By J 958, HFB had completed the project stage of the design of a turbojet airliner—the HFB 314. This was a short /medium‐range airliner designed to carry 70 tourist class passengers over ranges up to 1,250 miles. Although Hamburger Flugzeugbau had designed the aircraft in close co‐operation with Lufthansa, West Germany's largest airline, and were fully prepared to produce the aircraft in consort with other German or European companies, development costs would have amounted to some £5 million and since no Government financial support was forthcoming, the project was abandoned. Determined to reassert its authority as a design agency, HFB turned to the jet executive field in 1960 and designed the twin‐jet HFB 320 Hansa. The most distinctive feature of this aircraft is without doubt its sweptforward wing and it is this feature which is dealt with in detail in this article. The decision to utilize such a wing was based to some extent on Hamburger Flugzeugbaus‘ technical experience in the development of the Junkers Ju 287 sweptforward wing dating back to the Second World War. The HFB 320 Hansa is powered by two General Electric CJ 610–1 turbo‐jets, each of which has a weight of 355 lb. and a thrust of 2,850 lb. The engine's eight‐stage axial compressor has a mass flow of 565 at. ft. I sec. at 16,500 r.p.m. At gross weights of 16,000 to 18,000 lb., the Hansa will cruise at 500 m.p.h. over ranges up to 1,600 miles with full reserves. Well over 2,000 hours of model testing have been carried out in wind tunnels at the Aerodynamische Versuchsanstalt, (Goettingen), National Luchten Ruimtvaartlaboratorium (Amsterdam), Torrejon (Madrid), Emmen (Switzerland) and Modane (France).‐ Static testing is underway on an airframe structural specimen including: test for maximum cabin pressure, windshield strength test—bird impact, investigation of ground and landing loads, and investigation of loading at the extremes of the flight envelope. Later this summer, HFB will commence a programme of loading tests of a dynamic test airframe utilizing the water tank technique, involving pressurization cycles and gust loading to simulate 50,000 flights. Assembly of the first prototype HFB 320 Hansa was completed on March 18, 1964, and was followed by ground resonance tests, and engine ground’ running prior to the aircraft's maiden flight on April 21. The prototype, which carries extensive flight test instrumentation and is not equipped with the production‐type cabin, made its first public appearance at the Deutsches Luftfahrtschau at Hanover‐Langenhagen a few days later. The full flight test programme is currently being pursued.

THE automatic flight control system (AFCS) for the Concorde has been jointly developed by Elliott‐Automation Ltd. and SFENA (Société Francaise pour la Navigation Aérienne) for the production aircraft. Elliott carry the overall design responsibility and the equipment will be supported in the field by both Elliott and SFENA. The pitch axis of the autopilot and flight director, the autothrottle, all aspects of the control of speed, all pilot/ AFCS interfaces and the landing display are Elliott responsibilities for the pre‐production and production aircraft, while SFENA are responsible for the three‐axis autostabiliser, azimuth axes of the autopilot and flight director, electric trim system and the flight test instrumentation for the AFCS. The Bendix Corporation participated in the programme for the prototype aircraft with the design and manufacture of the azimuth axes of the autopilot and flight director, and the electric trim system.

The purpose of this paper is to describe the longitudinal aerodynamic characterization of an unmanned cropped delta configuration from real flight data. In order to perform this task an unmanned configuration with cropped delta planform and rectangular cross-section has been designed, fabricated, instrumented and flight tested at flight laboratory in Indian Institute of Technology Kanpur (IITK), India.

As a part of flight test program a real flight database, through various maneuvers, have been generated for the designed unmanned configuration. A dedicated flight data acquisition system, capable of onboard logging and telemetry to ground station, has been used to record the flight data during these flight test experiments. In order to identify the systematic errors in the measurements, the generated flight data has been processed through data compatibility check.

It is observed from the flight path reconstruction that the obtained biases are negligible and the scale factors are almost close to unity. The linear aerodynamic model along with maximum likelihood and least-square methods have been used to perform the parameter estimation from the obtained compatible flight data. The lower values of Cramer-Rao bounds obtained for various parameters has shown significant confidence in the estimated parameters using maximum likelihood method. In order to validate the aerodynamic model used and to increase the confidence in the estimated parameters a proof-of-match exercise has been carried out.

The entire work presented is original and all the experiments have been carried out in Flight laboratory of IITK.

The purpose of this paper is to assess state-of-the-art techniques for quantifying flow distortion in the inlets of turbofan engines, particularly with respect to the prospects for future flight applications.

To adequately characterize the flow fields of complex aircraft inlet distortions, the author has incorporated laser velocimetry techniques, namely, stereoscopic particle image velocimetry (PIV) and Doppler velocimetry based on filtered Rayleigh scattering (FRS), into inlet distortion studies.

Overall, the results and experience indicate that the pathway for integration of FRS technologies into flight systems is clearer and more robust than that of PIV.

While always a concern, the topic of inlet distortion has grown in importance as contemporary airframe designers seek extremely compact and highly integrated inlets. This research offers a means for gaining new understanding of the in situ aerodynamic phenomena involved with complex inlet distortion.

This paper presents unique applications of turbofan inlet velocimetry methods while providing an original assessment of technological challenges involved with progressing advanced velocimetry techniques for flight measurements.

A description of how oxygen pressure vessels for the prototype B.A.C./Sud Concorde are manufactured from seamless steel tubing produced by the Weldless works of Tubes Limited and an outline of the salient features of the Concorde's oxygen system for crew and passengers. On February 28, 1968—just fourteen months hence—the first prototype Concorde supersonic airliner (FIG. 1) will make its maiden flight from the Toulouse‐Blagnac airfield in France. Six months later the second prototype will make its first flight from British Aircraft Corporation's airfield at Filton, Bristol. In September 1969, and November 1969, respectively, two pre‐production aircraft will fly for the first time—these having a longer fuselage, higher gross weight, additional fuel capacity and higher payload capacity than the prototype aircraft. Apart from the fact that the pre‐production types will carry full flight test instrumentation, they will be fully representative of production Concordes—60 of which have already been ordered for service with thirteen leading world airlines.

The purpose of this paper is to build a neural model of an aircraft from flight data and online estimation of the aerodynamic derivatives from established neural model.

A neural model capable of predicting generalized force and moment coefficients of an aircraft using measured motion and control variable is used to extract aerodynamic derivatives. The use of neural partial differentiation (NPD) method to the multi-input-multi-output (MIMO) aircraft system for the online estimation of aerodynamic parameters from flight data is extended.

The estimation of aerodynamic derivatives of rigid and flexible aircrafts is treated separately. In the case of rigid aircraft, longitudinal and lateral-directional derivatives are estimated from flight data. Whereas simulated data are used for a flexible aircraft in the absence of its flight data. The unknown frequencies of structural modes of flexible aircraft are also identified as part of estimation problem in addition to the stability and control derivatives. The estimated results are compared with the parameter estimates obtained from output error method. The validity of estimates has been checked by the model validation method, wherein the estimated model response is matched with the flight data that are not used for estimating the derivatives.

Compared to the Delta and Zero methods of neural networks for parameter estimation, the NPD method has an additional advantage of providing the direct theoretical insight into the statistical information (standard deviation and relative standard deviation) of estimates from noisy data. The NPD method does not require the initial value of estimates, but it requires a priori information about the model structure of aircraft dynamics to extract the flight stability and control parameters. In the case of aircraft with a high degree of flexibility, aircraft dynamics may contain many parameters that are required to be estimated. Thus, NPD seems to be a more appropriate method for the flexible aircraft parameter estimation, as it has potential to estimate most of the parameters without having the issue of convergence.

This paper highlights the application of NPD for MIMO aircraft system; previously it was used only for multi-input and single-output system for extraction of parameters. The neural modeling and application of NPD approach to the MIMO aircraft system facilitate to the design of neural network-based adaptive flight control system. Some interesting results of parameter estimation of flexible aircraft are also presented from established neural model using simulated data as a novelty. This gives more value addition to analyzing the flight data of flexible aircraft as it is a challenging problem in parameter estimation of flexible aircraft.

Aero Systems of Miami, Florida, specialises in the sale of like‐new, FAA overhauled certified aircraft rotable equipment at a fraction of the cost and lead time required by the factory. Aero Systems will be exhibiting for the first time in Britain and are seeking an agent for the UK and Europe.