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SINCE the Report of the investigations into the causes and circumstances of the accident to R.101 do not bring out any noticeably new facts, and in general can be said to bear out the statements made and conclusions arrived at m the article on the accident published in AIRCRAFT ENGINEERING, Vol. II, November, 1930, pp. 278–280, it does not appear necessary to publish here any extended summary of it, particularly as this has been amply done elsewhere. It may, however, be well to give the authenticated figures of the weight and lift of the airship, as given in the Report, as they differ somewhat from the estimates published in the article already referred to. As originally designed, the hull was 732 feet long, with a maximum diameter of 132 feet, the total gasbag capacity being 4,998,500 cubic feet, giving a gross lift of 148 6 tons. The fixed weights amounted to 113·6 tons, leaving a useful lift of 35 tons, instead of the 60 tons for which the specification had called. To remedy this deficiency the servo control and certain fittings were removed, giving a gain of 2·3 tons, and the gasbag wiring was let out, giving a further gain of 3·4 tons; the total gain from these modifications being 5·7 tons. In addition to these alterations, an extra bay (8a) containing a gasbag with a opacity of 510,300 cubic feet was inserted, which resulted in a further net gain of 8·6 tons. After these modifications the length of the hull was 777 feet, the maximum diameter remaining the same as before, and the total gasbag capacity had been increased to 5,508,800 cubic feet, giving a gross lift of 167·2 tons. The fixed weights now amounted to 117·9 tons, leaving a useful lift of 49·3 tons.

Aircraft pitch control is fundamental for the performance of micro aerial vehicles (MAVs). The purpose of this paper is to establish a simple experimental procedure to calibrate pitch instrumentation and classical control algorithms. This includes developing an efficient pitch angle observer with optimal estimation and evaluating controllers under uncertainty and external disturbances.

A wind tunnel test bench is designed to simulate fixed-wing aircraft dynamics. Key elements of the instrumentation commonly found in MAVs are characterized in a gyroscopic test bench. A data fusion algorithm is calibrated to match the gyroscopic test bench measurements and is then integrated into the autopilot platform. The elevator-angle to pitch-angle dynamic model is obtained experimentally. Two different control algorithms, based on model-free and model-based approaches, are designed. These controllers are analyzed in terms of parametric uncertainties due to wind speed variations and external perturbation because of sudden weight distribution changes. A series of experimental tests is performed in wind-tunnel facilities to highlight the main features of each control approach.

With regard to the instrumentation algorithms, a simple experimental methodology for the design of optimal pitch angle observer is presented and validated experimentally. In the context of the platform design and identification, the similitude among the theoretical and experimental responses shows that the platform is suitable for typical pitch control assessment. The wind tunnel experiments show that a fixed linear controller, designed using classical frequency domain concepts, is able to provide adequate responses in scenarios that approximate the operation of MAVs.

The aircraft orientation observer can be used for both pitch and roll angles. However, for simultaneousyaw angle estimation the proposed design method requires further research. The model analysis considers a wind speed range of 6-18 m/s, with a nominal operation of 12 m/s. The maximum experimentally tested reference for the pitch angle controller was 20°. Further operating conditions may require more complex control approaches (e.g. scheduling, non-linear, etc.). However, this operating range is enough for typical MAV missions.

The study shows the design of an effective pitch angle observer, based on a simple experimental approach, which achieved locally optimum estimates at the test conditions. Additionally, the instrumentation and design of a test bench for typical pitch control assessment in wind tunnel facilities is presented. Finally, the study presents the development of a simple controller that provides adequate responses in scenarios that approximate the operation of MAVs, including perturbations that resemble package delivery and parametric uncertainty due to wind speed variations.

This paper aims to present the idea of an automatic control system dedicated to small manned and unmanned aircraft performing manoeuvres other than those necessary to perform a so-called standard flight. The character of these manoeuvres and the range of aircraft flight parameter changes restrict application of standard control algorithms. In many cases, they also limit the possibility to acquire complete information about aircraft flight parameters. This paper analyses an alternative solution that can be applied in such cases. The loop manoeuvre, an element of aerobatic flight, was selected as a working example.

This paper used theoretical discussion and breakdowns to create basics for designing structures of control algorithms. A simplified analytical approach was then applied to tune regulators. Research results were verified in a series of computer-based software-in-the-loop rig test computer simulations.

The structure of the control system enabling aerobatic flight was found and the method for tuning regulators was also created.

The findings could be a foundation for autopilots working in non-conventional flight scenarios and automatic aircraft recovery systems.

This paper presents the author’s original approach to aircraft automated control where high precision control is not the priority and flight parameters cannot be precisely measured or determined.

The purpose of this paper is to describe one example of an academic library using existing internal expertise and targeted events to provide training for liaison librarians in support of new scholarly communication initiatives.

This article presents a case study of how a medium-size academic library without a designated scholarly communications librarian or office presented a series of open access (OA) training opportunities for the liaison librarians in preparation for the official launch of the institutional repository and the campus’ inaugural participation in OA week.

The multiple opportunities to engage with the topics in diverse ways resulted in librarians being more comfortable with discussing OA with their departmental faculty. Opinions of OA were changed as a result of attending the events. Participants found the activities to be useful and were engaged enough with the topic to ask for specific areas where they would like more training opportunities. Look to other colleagues both on campus and in the broader region to tap their expertise or explore professional organizations or free webinars. Taking the initiative to organize events that require minimal effort can have a big impact.

Librarians have limited opportunity for in-depth training to gain new competencies and re-tool their skills to match current demands; this article demonstrates that utilizing internal expertise to provide a variety of training can positively impact participants’ attitudes and confidence.

This article presents methods and rationale for librarians to facilitate similar professional development opportunities for building new scholarly communication competencies in support of the emerging research and scholarly publishing trends.

High autogyro accident rates prompted experimental investigation of this type of aircraft's low‐speed pitch characteristics. Pitch control is typically derived from main rotor tip‐path‐plane adjustment. Thus, autogyro designers often omit horizontal tails and pitch control surfaces. The purpose of this paper is to enable autogyro low‐speed pitch control by intentionally placing elevators in the propeller wake.

Wind tunnel tests were conducted on a 1:10 scale teetering rotor autogyro model. The model included a horizontal tail with elevators placed in the propeller wake. Straight‐and‐level flight conditions were estimated via a scaling scheme based on the main rotor diameter. At minimum flight speed, the pitching moment induced by 30° elevator deflection was measured. This process was repeated for a range of elevator positions behind the centre of the pitching rotation.

When placed in an autogyro propeller wake, deflected elevators induce significant pitching moments. If the elevator is shadowed from free stream flow by the autogyro cowling, the pitching moment remains unchanged regardless of the distance between elevators and centre of pitch rotation. However, if the elevator is immersed in the freestream, the pitching moment increases via deflection of both propeller wake and freestream flow.

Kinematic similarity ensures ratios between propeller wake, wind speed, and main rotor flows are representative of full scale. Without flow visualization, main‐rotor‐diameter‐based scaling does not ensure kinematic similarity. Results are therefore qualitative.

Elevators mounted in autogyro propeller wake are worthy of inclusion on all autogyros for pitch control at low speed.

Improved low‐speed pitch control arising from elevators mounted in autogyro propeller wake could potentially reduce accidents.

The general reasons for considering a fresh approach to the calculation of air‐worthiness design tail loads and associated torques due to elevator‐induced pitching manoeuvres are discussed. Then follows a description of the manoeuvre itself, elevator actions to be assumed, and the proposed method of calculating the various response quantities. The analytical treatment of Czaykowski given to the unchecked manoeuvre is extended to cover the checked case in Appendix I, Part III and a comparison is made of the two types of manoeuvre. The application of the work to auto‐pilot feed‐back failure causing hunting of the elevator control is also dealt with. The effect of aircraft size, weight, e.g. position, forward speed and altitude on the various response quantities are discussed, with particular emphasis on the importance of the manoeuvre margin. To avoid possible confusion of terms the two types of elevator‐induced manoeuvre mentioned above and discussed in this paper are defined as follows:

The purpose of this paper is to describe the evolution of a blended learning strategy in a company law course for accounting students and to evaluate its impact on assessment and student self-reflection.

A case study approach is used to describe the development of blended learning technologies within an elevator pitch assessment item in four cohorts over a two-year period. This is complemented by teacher observations, an online survey and student interviews to evaluate the assessment item, the technology used and its impact as a self-reflection and assessment tool.

The case study reveals the benefits of blended learning technologies but also a series of logistical, assessment-related, behavioural and technological issues and how these issues were addressed. The preliminary evidence from the online survey and student interviews suggests that the blended learning technologies have facilitated flexibility in assessment (both from a student and teacher perspective), student self-reflection and fairness in assessment practices.

The study identifies the benefits of and likely issues facing educators when considering the deployment of blended learning technologies to teach and assess oral communication skills. The paper contributes to pedagogy by describing the innovative use of video cameras in assessing elevator pitches and extends the literature on video presentations in higher education, in particular, its positive influence on student self-reflection.

By application of the analytical method to a wide range of current aircraft types an approximate form of the method is developed for the quick estimation of tail load maxima and associated torques during the checked manoeuvre and the same is also confirmed for the unchecked manoeuvre of Ref. (3). Numerical values of critical elevator actions to be associated with the airworthiness design case are considered and hence, from a comparison with the approximate method, the limitations of the present empirical approach given in British and American civil airworthiness regulations are brought to light.