Operational experience with a powered-lift STOL aircraft

The experience gained in over four years of STOL operations with the augmentor wing research aircraft and the background of operation of other STOL powered-lift aircraft indicate that the use and percent of lift achieved by powered lift have significant effects on the operational characteristics of STOL aircraft and, therefore, on the performance that can be achieved. A brief description of the augmentor wing including the means by which it achieves its powered lift is presented. Specific problem areas relating to the control of longitudinal flight path are discussed as well as the consequences these might have on the design and operation of this class of aircraft. Particular emphasis is given to the approach and landing phase of flight where the consequences of the powered lift are most pronounced, and the resultant characteristics most different from those of conventional aircraft

A Flight Investigation of the STOL Characteristics of an Augmented Jet Flap STOL Research Aircraft

The flight test program objectives are: (1) To determine the in-flight aerodynamic, performance, and handling qualities of a jet STOL aircraft incorporating the augmented jet flap concept; (2) to compare the results obtained in flight with characteristics predicted from wind tunnel and simulator test results; (3) to contribute to the development of criteria for design and operation of jet STOL transport aircraft; and (4) to provide a jet STOL transport aircraft for STOL systems research and development. Results obtained during the first 8 months of proof-of-concept flight testing of the aircraft in STOL configurations are reported. Included are a brief description of the aircraft, fan-jet engines, and systems; a discussion of the aerodynamic, stability and control, and STOL performance; and pilot opinion of the handling qualities and operational characteristics

The Awara verbal system

Awara is a language in the Wantoat family spoken by the Awara people of Papua New Guinea. Though it has been mentioned in papers written about the Finisterre-Huon languages and about the Wantoat language (another language in the Wantoat family), it has not been described in depth. This paper presents a description of the verbal system of the Awara language. The major grammatical constructions described are 1) the verbal morphology, 2) serial-verb constructions, 3) clause chaining, and 4) subordination. Interesting aspects of the language shown here are 1) the variety of clause types based on the type of subject-indexing suffix, if any, used on the clause and 2) the variety of structures and functions of serial-verb constructions. Awara also shows the need to make the distinctions between certain categories of clauses. The switch-reference system in Awara shows a distinction between the reference clause, with respect to which switch-reference subject-indexing is marked, and the finite clause, on which the marked clause depends for tense or modality. Awara also shows the need to distinguish the concepts of subordination and dependency. Awara has two kinds of dependent clauses: 1) subordinate clauses, which are ignored by the switch-reference marking of the clauses around them, and 2) cosubordinate clauses, which participate in the switch-reference system and also have a distinct morphological pattern from subordinate clauses and from independent clauses

Flight investigation of methods for implementing noise-abatement landing approaches

Flight tests and simulation of steep noise reducing landing approaches with jet transpor

Lattice thermal conductivity of graphene nanostructures

Non-equilibrium molecular dynamics is used to investigate the heat current due to the atomic lattice vibrations in graphene nanoribbons and nanorings under a thermal gradient. We consider a wide range of temperature, nanoribbon widths up to 6nm and the effect of moderate edge disorder. We find that narrow graphene nanorings can efficiently suppress the lattice thermal conductivity at low temperatures (~100K), as compared to nanoribbons of the same width. Remarkably, rough edges do not appear to have a large impact on lattice energy transport through graphene nanorings while nanoribbons seem more affected by imperfections. Furthermore, we demonstrate that the effects of hydrogen-saturated edges can be neglected in these graphene nanostructures