SCIENTIFIC AND TECHNICAL AEROSPACE REPORTS

A Biweekly Publication of the National Aeronautics and Space Administration
VOLUME 44, ISSUE 11 - MAY 30, 2006

03 AIR TRANSPORTATION AND SAFETY
Includes passenger and cargo air transport operations; airport ground operations; flight safety and hazards; and aircraft accidents.

Systems and hardware specific to ground operations of aircraft and to airport construction are covered in 09 Research and Support Facilities (Air).

Air traffic control is covered in 04 Aircraft Communications and Navigation.

For related information see also 16 Space Transportation and Safety and 85 Technology Utilization and Surface Transportation.

20060013307 Hughes Technical Center, Atlantic City International Airport, NJ, USA

Alpha Factor Determination Using Data Collected at the National Airport Pavement Test Facility

Hayhoe, G. F.; Mar. 2006; 40 pp.; In English Report No.(s): PB2006-109055; No Copyright; Avail.: National Technical Information Service (NTIS)

Full-scale test data for multiple-wheel, heavy gear load (MWHGL) loading of flexible airport pavements are summarized from three separate test series: one test series, the MWHGL tests, was conducted by the U.S. Army Corps of Engineers (USACE), and the other two series of tests were conducted by the Federal Aviation Administration (FAA) at the National Airport Pavement Test Facility (NAPTF). The MWHGL pavement structural configuration was used as the reference, and all NAPTF structures were converted to equivalent reference structures by the use of thickness equivalency factors relating the NAPTF and the MWHGL structural materials. Load repetition factors (alpha factors), required for the computation of pavement thickness by the California Bearing Ratio (CBR) design procedure for flexible airport pavements, were calculated for the NAPTF test data and plotted with the MWHGL alpha factors. Least squares quadratic curve fits were computed for the four- and six-wheel alpha factors, and the alpha factors at 10,000 coverages were computed for comparison with the International Civil Aviation Organization (ICAO) standard for computing Aircraft Classification Number (ACN). The results of the analysis are consistent with the existing alpha factor of 0.825 for four-wheel gears, but the results of the analysis are not consistent with the existing alpha factor of 0.788 for six-wheel gears. The six-wheel alpha factor at 10,000 coverages should be changed to a value approximately equal to the interim value of 0.72 adopted by the ICAO for calculating ACN for six-wheel gears. NTIS

Airports; Pavements; Test Facilities

20060013393 Civil Aerospace Medical Inst., Oklahoma City, OK, USA

Beneath the Tip of the Iceberg: A Human Factors Analysis of General Aviation Accidents in Alaska Versus the Rest of the USA

Detwiler, Cristy A.; Hackworth, Carla A.; Holcomb, Kali A.; Boquet, Albert J.; Pfleiderer, Elaine; Wiegmann, Douglas A.; Shappell, Scott A.; March 2006; 14 pp.; In English; Original contains black and white illustrations Contract(s)/Grant(s): AM-B-05-HRR-521 Report No.(s): DOT/FAA/AM-06/7; Copyright; Avail.: CASI: A03, Hardcopy

Historically, general aviation (GA) accidents have been overlooked and their impact under-appreciated when compared with those in the commercial or military sector. Recently however, the Federal Aviation Administration and other governmental and civilian organizations have focused their attention on one piece of this proverbial 'iceberg,' that being GA accidents occurring in Alaska. This study examines more than 17,000 GA accidents using the Human Factors Analysis and Classification System. Comparisons of Alaska to the rest of the U.S. (RoUS) included traditional demographic and environmental variables, as well as the human errors committed by aircrews. Overall, categorical differences among unsafe facts (decision errors, skill-based errors, perceptual errors, and violations) committed by pilots involved in accidents in Alaska and those in the RoUS were minimal. However, a closer inspection of the data revealed notable variations in the specific forms these unsafe acts took within the accident record. Specifically, skill-based errors associated with loss of directional control were more likely to occur in Alaska than the rest of the U.S. Likewise, the decision to utilize unsuitable terrain was more likely to occur in Alaska. Additionally, accidents in Alaska were associated with violations concerning Visual Flight Rules into Instrument Meteorological Conditions. These data provide valuable information for those government and civilian programs tasked with improving GA safety in Alaska and the RoUS. Author

Human Factors Engineering; Aircraft Accidents; Classifications; Directional Control; Visual Flight Rules; Safety; Perceptual Errors; Inspection; General Aviation Aircraft

20060013453 NASA Glenn Research Center, Cleveland, OH, USA

Progress in the Development of Practical Remote Detection of Icing Conditions

Reehorst, Andrew; Politovich, Marcia K.; Zednik, Stephan; Isaac, George A.; Cober, Stewart; April 2006; 17 pp.; In English; Original contains color illustrations Contract(s)/Grant(s): WBS 866.02.07.03 Report No.(s): NASA/TM-2006-214242; E-15488; Copyright; Avail.: CASI: A03, Hardcopy

The NASA Icing Remote Sensing System (NIRSS) has been under definition and development at NASA Glenn Research Center since 1997. The goal of this development activity is to produce and demonstrate the required sensing and data processing technologies required to accurately remotely detect and measure icing conditions aloft. As part of that effort NASA has teamed with NCAR to develop software to fuse data from multiple instruments into a single detected icing condition product. The multiple instrument approach utilizes a X-band vertical staring radar, a multifrequency microwave, and a lidar ceilometer. The radar data determine cloud boundaries, the radiometer determines the sub-freezing temperature heights and total liquid water content, and the ceilometer refines the lower cloud boundary. Data is post-processed with a LabVIEW program with a resultant supercooled liquid water profile and aircraft hazard depiction. Ground-based, remotely-sensed measurements and in-situ measurements from research aircraft were gathered during the international 2003-2004 Alliance Icing Research Study (AIRS II). Comparisons between the remote sensing system s fused icing product and the aircraft measurements are reviewed here. While there are areas where improvement can be made, the cases examined suggest that the fused sensor remote sensing technique appears to be a valid approach. Author

Aircraft Icing; Remote Sensing; Data Processing; Radiometers; Radar Data; Ice Formation; In Situ Measurement; Superhigh Frequencies

Source: NASA