Technology needs for high speed rotorcraft (3)

The spectrum of vertical takeoff and landing (VTOL) type aircraft is examined to determine which aircraft are most likely to achieve high subsonic cruise speeds and have hover qualities similar to a helicopter. Two civil mission profiles are considered: a 600-n.mi. mission for a 15- and a 30-passenger payload. Applying current technology, only the 15- and 30-passenger tiltfold aircraft are capable of attaining the 450-knot design goal. The two tiltfold aircraft at 450 knots and a 30-passenger tiltrotor at 375 knots were further developed for the Task II technology analysis. A program called High-Speed Total Envelope Proprotor (HI-STEP) is recommended to meet several of these issues based on the tiltrotor concept. A program called Tiltfold System (TFS) is recommended based on the tiltrotor concept. A task is identified to resolve the best design speed from productivity and demand considerations based on the technology that emerges from the recommended programs. HI-STEP's goals are to investigate propulsive efficiency, maneuver loads, and aeroelastic stability. Programs currently in progress that may meet the other technology needs include the Integrated High Performance Turbine Engine Technology (IHPTET) (NASA Lewis) and the Advanced Structural Concepts Program funded through NASA Langley

Parallel Associations and the Structure of Autobiographical Knowledge

The self-memory system (SMS) model of autobiographical knowledge conceives that memories are structured thematically, organized both hierarchically and temporally. This model has been challenged on several fronts, including the absence of parallel linkages across pathways. Calendar survey interviewing shows the frequent and varied use of parallel associations in autobiographical recall. Parallel associations in these data are commonplace, and are driven more by respondents? generative retrieval than by interviewers? probing. Parallel associations represent a number of autobiographical knowledge themes that are interrelated across life domains. The content of parallel associations is nearly evenly split between general and transitional events, supporting the importance of transitions in autographical memory. Associations in respondents? memories (both parallel and sequential), demonstrate complex interactions with interviewer verbal behaviors during generative retrieval. In addition to discussing the implications of these results to the SMS model, implications are also drawn for transition theory and the basic-systems model