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This study aims to present a diagnosis method to inspect the structure health for aging transport aircraft based on the postflight data in severe clear-air turbulence at transonic flight. The purpose of this method development is to assist certificate holder of aircraft maintenance factory as a complementary tool for the structural maintenance program to ensure that the transport aircraft fits airworthiness standards.

In this study, the numerical approach to analyze the characteristics of flight dynamic and static aeroelasticity for two four-jet transport aircraft will be presented. One of these two four-jet transport aircraft is an aging one. Another one is used to demonstrate the order of magnitude of the static aeroelastic behaviors. The nonlinear unsteady aerodynamic models are established through flight data mining and the fuzzy-logic modeling technique based on postflight data. The first and second derivatives of flight dynamic and static aeroelastic behaviors, respectively, are then estimated by using these aerodynamic models.

Although the highest dynamic pressure of aging aircraft is lower, the highest absolute value of static aeroelastic effects response to the wing of aging aircraft is about 3.05 times larger than normal one; the magnitude variations of angles of attack are similar for both aircrafts; the highest absolute value of the static aeroelastic effects response to the empennage of aging aircraft is about 29.67 times larger than normal one in severe clear-air turbulence. The stabilizer of aging aircraft has irregular deviations with obvious jackscrew assembly problems, as found in this study.

A lack of the measurement data of vertical wind speed sensor on board to verify the estimated values of damping term is one of the research limitations of this study. This research involved potential problem monitoring of structure health for transport aircraft in different weights, different sizes and different service years. In the future research, one can consider more structural integrity issues for other types of aircraft.

It can be realized from this study that the structure of aging transport aircraft may have potential safety threat. Therefore, when the airline managed aging transport aircraft, it ought to be conducted comprehensive and in-depth inspections to reduce such safety risks and establish a complete set of safety early warning measures to deal with the potential problem of aircraft aging.

It can be realized that the structure of aging transport aircraft has potential safety threat. The airline managed aging transport aircraft; it should conduct comprehensive and in-depth inspections to reduce safety risks and establish a complete set of safety early warning measures.

This method can be used to assist airlines to monitor aging transport aircraft as a complementary tool of structural maintenance program to improve aviation safety, operation and operational efficiency.

The purpose of this paper is to present a quick inspection method based on the post-flight data to examine static aeroelastic behavior for transport aircraft subjected to instantaneous high g-loads.

In the present study, the numerical approach of static aeroelasticity and two verified cases will be presented. The non-linear unsteady aerodynamic models are established through flight data mining and the fuzzy-logic modeling of artificial intelligence techniques based on post-flight data. The first and second derivatives of flight dynamic and static aeroelastic behaviors, respectively, are then estimated by using these aerodynamic models.

The flight dynamic and static aeroelastic behaviors with instantaneous high g-load for the two transports will be analyzed and make a comparison study. The circumstance of turbulence encounter of the new twin-jet is much serious than that of four-jet transport aircraft, but the characteristic of stability and controllability for the new twin-jet is better than those of the four-jet transport aircraft; the new twin-jet transport is also shown to have very small aeroelastic effects. The static aeroelastic behaviors for the two different types can be assessed by using this method.

As the present study uses the flight data stored in a quick access recorder, an intrusive structural inspection of the post-flight can be avoided. A tentative conclusion is to prove that this method can be adapted to examine the static aeroelastic effects for transport aircraft of different weights, different sizes and different service years in tracking static aeroelastic behavior of existing different types of aircraft. In future research, one can consider to have more issues of other types of aircraft with high composite structure weight.

This method can be used to assist airlines to monitor the variations of flight dynamic and static aeroelastic behaviors as a complementary tool for management to improve aviation safety, operation and operational efficiency.

Under this beading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Council, Reports and Technical Memoranda of the United States National Advisory Committee for Aeronautics and publications of other similar Research Bodies as issued

The characteristics and physical structure of the jet stream are described. The relationship of the jet stream to the general circulation in the atmosphere is illustrated by considering, first, the low level wind flow over the northern hemisphere and then the high level flow pattern (over 10,000 ft.). The seasonal change in position of jet streams and typical thermal and wind velocity cross‐sections are discussed. High altitude clear air turbulence is found to be associated with the periphery of the jet stream. The utilization of the jet‐stream as a wind‐aid in civil airline operations is discussed with reference to Pan‐American flights across the Atlantic and the Pacific.

Two events are described, both involving elevators but otherwise differing greatly in type of aircraft and nature of accident or incident. The first involves an HS 748 which was nearing the end of a flight to Newcastle from Dublin and was established on the localiser for runway 07, approximately 20 n miles out. As it passed through flight level 065 at a speed of approximately 200 knots, the pilot was easing forward on the control column when a sharp buffet was felt coincident with a slight nose pitch up. With no further abnormal events occurring, the aircraft continued normally and performed an unremarkable landing, the crew attributing the event to local clear air turbulence although conditions had been generally stable throughout the flight.

Equipment, Programmes, Techniques and Projects. The UM721 Modular Reflectoscope, claimed to be the world's most versatile ultrasonic flaw detection system, is now being manufactured by Watson & Sons (Electro‐Medical) Ltd., to the designs of the Sperry Products Division of Automation Industries Inc., of the U.S.A.

NASA's role in aeronautics is, by charter, to improve the usefulness, performance, speed, safety, and efficiency of U.S. civil and military aeronautical vehicles and to preserve U.S. leadership in aeronautical science and technology and its applications. To fill that role, NASA has oriented its aeronautics research and technology (R & T) programme to meet the near‐term and far‐term technology needs of the aviation industry, aircraft operators, government regulatory agencies, and the military services. NASA coordinates closely with those organizations in defining the R & T needs and the objectives for its aeronautics programme. The programme objective of potentially greatest interest to attendees of the International Air Safety Seminar is “To generate technology required for safer, more economical, efficient, fuel‐conservative, and environmentally acceptable air transportation systems to satisfy current and projected national needs.” In the spirit of this international meeting, I should note that certain NASA aeronautical research disciplines include cooperative efforts with the government aeronautical research organizations of several foreign countries.

Purpose – To examine the relationship between aviation and climate change, and the international dimensions of air transport.

Methodology/approach – A review of aviation's impacts on the global climate, mitigation strategies to reduce this impact, and the possible consequences of climate change for commercial aviation.

Findings – Although a range of mitigation measures have been developed and implemented to reduce aircraft emissions in the short term, with some environmental benefit, there is a real need for the aviation sector to identify the possible impacts of climate change on air travel operations, both to aircraft in flight and to operations at airports. A further challenge will be to devise adaptation plans that will address the vulnerabilities and thus ensure safe aviation-related operations.

Social implications – The climate change impacts of aviation will adversely affect society. In addition, some individuals may have to reduce or stop flying as a result of increased taxes and legislation implemented in response to climate change.

Originality/value of paper – There is a novel focus on the adaptation challenges for the aviation industry in response to climate change.

Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Council, Reports and Technical Memoranda of the United States National Advisory Committee for Aeronautics and publications of other similar Research Bodies as issued.

Under this heading are given each month the principal articles of aeronautical interest appearing in the current issues of the Journals of the leading Professional Societies and Institutions.