Flying qualities design criteria applicable to supersonic cruise aircraft

A comprehensive set of flying qualities design criteria was prepared for use in the supersonic cruise research program. The framework for stating the design criteria is established and design criteria are included which address specific failures, approach to dangerous flight conditions, flight at high angle of attack, longitudinal and lateral directional stability and control, the primary flight control system, and secondary flight controls. Examples are given of lateral directional design criteria limiting lateral accelerations at the cockpit, time to roll through 30 deg of bank, and time delay in the pilot's command path. Flight test data from the Concorde certification program are used to substantiate a number of the proposed design criteria

Application of Calspan pitch rate control system to the Space Shuttle for approach and landing

A pitch rate control system designed for use in the shuttle during approach and landing was analyzed and compared with a revised control system developed by NASA and the existing OFT control system. The design concept control system uses filtered pitch rate feedback with proportional plus integral paths in the forward loop. Control system parameters were designed as a function of flight configuration. Analysis included time and frequency domain techniques. Results indicate that both the Calspan and NASA systems significantly improve the flying qualities of the shuttle over the OFT. Better attitude and flight path control and less time delay are the primary reasons. The Calspan system is preferred because of reduced time delay and simpler mechanization. Further testing of the improved flight control systems in an in-flight simulator is recommended

Mission-oriented requirements for updating MIL-H-8501: Calspan proposed structure and rationale

This report documents the effort by Arvin/Calspan Corporation to formulate a revision of MIL-H-8501A in terms of Mission-Oriented Flying Qualities Requirements for Military Rotorcraft. Emphasis is placed on development of a specification structure which will permit addressing Operational Missions and Flight Phases, Flight Regions, Classification of Required Operational Capability, Categorization of Flight Phases, and Levels of Flying Qualities. A number of definitions is established to permit addressing the rotorcraft state, flight envelopes, environments, and the conditions under which degraded flying qualities are permitted. Tentative requirements are drafted for Required Operational Capability Class 1. Also included is a Background Information and Users Guide for the draft specification structure proposed for the MIL-H-8501A revision. The report also contains a discussion of critical data gaps and attempts to prioritize these data gaps and to suggest experiments that should be performed to generate data needed to support formulation of quantitative design criteria for the additional Operational Capability Classes 2, 3, and 4

Precession-driven changes in Iceland–Scotland Overflow Water penetration and bottom water circulation on Gardar Drift since ~ 200 ka

© The Author(s), 2015. This is the author's version of the work and is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Palaeogeography, Palaeoclimatology, Palaeoecology 440 (2015): 561-563, doi:10.1016/j.palaeo.2015.09.042.Benthic foraminiferal stable isotopic records from a transect of sediment cores south of the Iceland-Scotland Ridge reveal that the penetration depth of Iceland-Scotland Overflow Water (ISOW) varied on orbital timescales with precessional pacing over the past ~ 200 kyr. Similar, higher benthic foraminiferal δ13 C values (~ 1.0 ‰) were recorded at all transect sites downstream of the Iceland-Scotland Ridge during interglacial periods (Marine Isotope Chrons 5 and 1), indicating a deeply penetrating ISOW. During glacial periods (Marine Isotope Chrons 6, 4, and 2), benthic foraminiferal δ13C values from the deeper (2700-3300 m), southern sites within this transect were significantly lower (~ 0.5 ‰) than values from the northern (shallower) portion of the transect (~ 1.0 ‰), reflecting a shoaling of ISOW and greater influence of glacial Southern Component Water (SCW) in the deep Northeast Atlantic. Particularly during intermediate climate states, ISOW strength is driven by precesional cycles, superimposed on the large-scale glacial-interglacial ISOW variability. Millennial-scale variability in the penetration of ISOW, likely caused by high-frequency Heinrich and Dansgaard-Oeschger Events, is most pronounced during intermediate climate states.This research was supported by National Science Foundation grant OCE-0095219 to J.D. Wright2016-10-0

A study of pulsed thermography for life assessment of thin EB-PVD TBCs undergoing oxidation ageing

This paper presents an assessment of ageing for thin Thermal Barrier Coatings (TBC) using active thermography. As TBCs undergo ageing during their service life, sintering changes the porosity, elements migrate from the substrate, and micro-cracks build up in the structure of the material, exhibiting a change in thermal conductivity and diffusion properties. As the material ages and these properties change over time, it is possible to exploit trends in this change for characterisation of coating ageing, which would provide a diagnostics tool to estimate remaining useful life. In this study, through-depth diffusivity measurement has been applied to thin EB-PVD coatings which are artificially aged via oxidation furnace cycles. In order to address the difficulties of capturing a fast thermal event in a thin coating, a novel parametric study approach has been carried out to optimise data capture and analysis, maximising available frames for the model fitting step. Through-depth diffusivities have been measured during ageing for six samples, yielding a repeatable trend in thermal diffusivity measurements, with three features, which can be exploited for ageing characterisation of thin EB-PVD TBCs, and used as an alarm of imminent failure

Drawing identity: Beginning pre-service teachers’ professional identities

© 2015, Western Australian Institute for Educational Research Inc. All rights reserved. Developing a professional teacher identity can be complex as pre-service teachers engage with a process informed by their previous experiences of teachers and teaching, by learning in their pre-service course, by field placements, and by societal expectations. Using drawing as the method for gathering data, pre-service teachers in an Australian university were asked, prior to their first professional experience, to draw themselves as the teacher they hoped to become. Drawings (N=125) were coded according to the presence or absence of teacher, students and artefacts of teaching. Representations indicated that pre-service teachers identified themselves as teachers who would conduct enjoyable learning experiences, have positive relationships with their students and who were confident in themselves as a teacher. There was little evidence of the potential complexities or challenges of teaching, raising a dilemma for teacher educators in how to prepare pre-service teachers for the reality of the workplace while maintaining their positive approach

Pathways to resilience: how drawings reveal pre-service teachers’ core narratives underpinning their future teacher-selves

For this study of teacher-identity, which is part of a larger research project on teacher resilience, preservice teachers were invited to draw “the kind of teacher you hope to become”. In this, our study recognises drawing as a semiotic system of meaning-making and communication. The drawings were examined in terms of the “stories” they told. Using an emergent design approach to the data, drawings were synthesised into categories that were distilled into theme clusters. A hermeneutic reading revealed the core identity narrative underpinning each teacher-identity story. This story was told in sociocultural terms, or constructed around functioning at work or couched in terms of personal validation and achievement. These core identity narratives signal what “matters” to preservice teachers’ sense of their teacher-selves. Since there is an observed correlation between teacher-identity and resilience, knowing what matters is a helpful basis for building resilience