SCIENTIFIC AND TECHNICAL AEROSPACE REPORTS

A Biweekly Publication of the National Aeronautics and Space Administration
VOLUME 43, ISSUE 19 - SEPTEMBER 23, 2005

08 AIRCRAFT STABILITY AND CONTROL
Includes flight dynamics, aircraft handling qualities, piloting, flight controls, and autopilots.

For related information see also 05 Aircraft Design, Testing and Performance and 06 Avionics and Aircraft Instrumentation.

20050212394 Illinois Univ. at Urbana-Champaign, Urbana, IL USA

Supporting Battlefield Situation Assessment Through Attention Guidance and Diagnostic Aiding: A Cost-Benefit and Depth of Processing Analysis

Horrey, William J.; Wickens, Christopher D.; Dec. 2001; 69 pp.; In English; Original contains color illustrations Contract(s)/Grant(s): DAAL01-96-2-0003 Report No.(s): AD-A436776; ARL-01-16/FEDLAB-01-1; No Copyright; Avail: CASI; A04, Hardcopy

Automated support systems may be useful tools for aiding situation assessment in complex environments such as the military battlefield, medical diagnosis, and crisis management. These environments are marked by large amounts of information which often must be weighted and integrated into a meaningful judgment or assessment. Two experiments examined the effects of attention cueing and decision aiding on information integration tasks in static battlefield situations. In the first experiment, sixteen participants completed a resource allocation task for 56 battlefield scenarios (based on perceived threats). For half the trials, an automated system guided their attention to high-relevance information. On 2 trials a memory probe was administered to assess the depth of processing of information, and on the final trial an automation failure was presented. Results demonstrated an overall allocation performance advantage for automation but poorer recall for automation-enhanced units. Half of the participants failed to attend to the system failure. Those participants who detected the failure were inferred to have processed all of the cues more deeply based on their performance on the memory trials. In the second part, 12 participants completed the same task using an automated diagnostic aid (instead of the attention cueing). Again, performance was improved when using automation, more so than in experiment 1. However, there were costs associated with the processing of highly relevant information in these conditions. The costs and benefits of automated cueing and diagnostic aiding are discussed. DTIC

Cost Effectiveness; Data Processing; Information Systems; Situational Awareness

20050212395 Illinois Univ. at Urbana-Champaign, Urbana, IL USA

Constraints on Electronic Map Presentation and Terrain Depiction for Air-Ground Targeting: The Three Map Problem

Pringle, Heather; Wickens, Christopher D.; Ververs, Patricia M.; Jul. 1998; 20 pp.; In English; Original contains color illustrations Contract(s)/Grant(s): N00014-93-1-0253 Report No.(s): AD-A436777; ARL-98-3/NAWC-ONR-98-1; No Copyright; Avail: CASI; A03, Hardcopy

Seventeen pilots performed a flight simulation in which they flew toward a designated ground target, navigating across three legs and finally capturing the target. While they consulted the forward view depicted on an Evans and Sutherland display, two different means of presenting the terrain as an electronic map on an IRIS display were contrasted. In the ‘tiled’ method, the terrain was depicted by three 3D exo-centric maps, covering the distance between start and the final target, like three overlapping tiles. In the ‘global-local’ method, the depiction showed three maps, progressively increased in detail (more local coverage, less global coverage), by presenting only the remaining course between the initiation and final target destination. Pilots flew through (and located the target within) either sparse or dense terrain, and the target was defined by either cultural or natural features. The results revealed general equivalence between the two map presentation types, but a slight difference in favor of the global-local coverage, despite the fact that pilots preferred the tiled coverage because of its consistency of scale. Target search was superior in sparse terrain, whereas lateral tracking error, representing navigational performance, was superior in denser terrain, because of the greater richness of information upon which to base map vs. forward-view comparisons. There were no pronounced differences between cultural and natural features. DTIC

Digital Data; Flight SIMulation; Maps; Target Acquisition; Terrain

20050212396 Illinois Univ. at Urbana-Champaign, Urbana, IL USA

Integration of Information Sources of Varying Weights: The Effect of Display Features and Attention Cueing

Wickens, Christopher D.; Pringle, Heather L.; Merlo, James; Jan. 1999; 29 pp.; In English Contract(s)/Grant(s): DAAL01-96-2-0003 Report No.(s): AD-A436778; ARL-99-2/FEDLAB-99-1; No Copyright; Avail: CASI; A03, Hardcopy

This report reviews research in which multiple sources of variable reliability information are integrated for the purpose of making diagnostic judgments or allocating resources. A framework for considering these experiments is presented, and some evidence is presented regarding the extent to which humans are calibrated, in allocating processing proportionately to the ideal weights (i.e., reliability or importance) of information channels. Two generic sources of bias are identified. Attentional biases occur when more processing is given to less important channels, at the expense of more important ones (i.e., a failure to allocate attention optimally). Trust biases occur when less than fully reliable information is offered more processing than is warranted (i.e., ‘over trust’). A smaller number of specific studies are reviewed, and their conclusions are integrated, which have examined how multisource information processing is modulated by properties of the display of those sources. Two sources of display information are considered: attentional guidance, (e.g., cueing) directs attention to certain regions of the display. Reliability guidance explicitly displays the level of reliability of the information source(s). Each type of display can be explicitly designed to induce the appropriate behavior from the user, or can be a feature of the display that implicitly induces the relevant behavior. Generalizations regarding the effectiveness of these display features are sought from the studies reviewed. DTIC

Cues; Data Processing; Display Devices; Information Systems; Reliability

20050214047 Toledo Univ., OH, USA

MSU-TURBO Enhancements, 2, Aeroelastic Stability Analysis

Srivastava, Rakesh; NASA Glenn Research Center UEET (Ultra-Efficient Engine Technology) Program: Agenda and Abstracts; [2001], pp. 33; In English; See also 20050214031; No Copyright; Abstract Only; Available from CASI only as part of the entire parent document

Modem turbomachinery blade designs with forward sweep and lean are being used to improve the noise characteristics.

These geometric features coupled with the presence of shock can lead to flutter instability.

Accurate calculation of flutter stability for the modern blade geometry requires a three-dimensional viscous aeroelastic analysis.

An aeroelastic version of the serial MSU-TURBO code has been developed and has been applied to modem fan and compressor blade designs.

Results obtained for a transonic forward swept fan have shown good comparison with experimental measurements. Analysis of UEET compressor Rotor-2 has indicated the rotor to be stable. Author

Stability Tests; Aeroelasticity; Turbomachinery; Compressor Blades; Compressor Rotors

20050214373 NASA Langley Research Center, Hampton, VA, USA

Dynamics Modeling and Simulation of Large Transport Airplanes in Upset Conditions

Foster, John V.; Cunningham, Kevin; Fremaux, Charles M.; Shah, Gautam H.; Stewart, Eric C.; Rivers, Robert A.; Wilborn, James E.; Gato,William; [2005]; 13 pp.; In English; AIAA Guidance, Navigation, and Control Conference and Exhibit, 15-18 Aug. 2005, San Francisco, CA, USA; Original contains color and black and white illustrations Contract(s)/Grant(s): 23-079-30-31 Report No.(s): AIAA Paper 2005-5933; No Copyright; Avail: CASI; A03, Hardcopy

As part of NASA’s Aviation Safety and Security Program, research has been in progress to develop aerodynamic modeling methods for simulations that accurately predict the flight dynamics characteristics of large transport airplanes in upset conditions. The motivation for this research stems from the recognition that simulation is a vital tool for addressing loss-of-control accidents, including applications to pilot training, accident reconstruction, and advanced control system analysis. The ultimate goal of this effort is to contribute to the reduction of the fatal accident rate due to loss-of-control. Research activities have involved accident analyses, wind tunnel testing, and piloted simulation. Results have shown that significant improvements in simulation fidelity for upset conditions, compared to current training simulations, can be achieved using state-of-the-art wind tunnel testing and aerodynamic modeling methods. This paper provides a summary of research completed to date and includes discussion on key technical results, lessons learned, and future research needs. Author

Transport Aircraft; Dynamic Models; SIMulation; Wind Tunnel Tests; Flight Conditions; Controllability

Source: NASA.