A Design Concept for Alleviating Some Size Constrants for Large Aircraft

S OF PAPERS, 86th Annual Meeting of the Virginia Academy of Science, May 20-23, 2008, Hampton University, Hampton VA Aeronautical and Aerospace Sciences A DESIGN CONCEPT FOR ALLEVIATING SOME SIZE CONSTRANTS FOR LARGE AIRCRAFT. M. Leroy Spearman, NASA-Langley Research Center, Hampton, VA 23681. The basic wing-body-tail arrangement of conventional transport aircraft generally consists of a central fuselage with forward-mounted wing panels attached to each side, and with aft-mounted tail surfaces. This arrangement has remained essentially unchanged over the years. and increased capacity has been achieved simply by increasing the overall size of the aircraft. However such an approach may be limited for aircraft beyond the size of the current jumbo jets such as the Boeing 7 4 7. For very large aircraft a serious problem may occur from the trailing vortex flow that would be generated at the wing tips under lifting conditions. The tip vortex presents a hazard to trailing aircraft that may be upset if they fly into the path of the vortex. Such a vortex would be much stronger than that for current transports because of the increased lift required for the larger aircraft. In an effort to alleviate such a problem some research has been conducted with an unconventional design for a large aircraft. The design consists of a large rectangular wing surface with large bodies attached to each wing tip. There are no outboard, wing panels such as those used on conventional aircraft designs. The use of two bodies of a conventional aircraft design results in doubling the capacity of the conventional aircraft. The large area of the rectangular wing provides adequate lift to sustain flight. The tip-mounted bodies act as end plates for the wing and the formation of a trailing vortex is precluded. Wind tunnel tests have been made of such a concept using two simulated Boeing747 fuselages. Compared to a basic B-747, the resulting concept provides a payload capacity twice that of a B-7 4 7 with no increase in length, a decrease in span, and no trailing tip vortex. SOME EVENTS FROM THE FIRST CENTURY OF FLIGHT. M. Leroy Spearman, NASA-Langley Research Center, Hampton, VA 23681 & Robert W. Heath, RRMC, Newport News, VA. Leonardo da Vinci envisioned man-flight in the 15 century and designed a practical airplane concept in 1490. Many other pioneers proposed various types of flying machines over the next 400 years but it was not until December 17, 1903 that the Wright Brothers, at Kitty Hawk, NC, were credited with achieving the first manned-powered flight. Over the next 100 years, several factors have influenced advances in aviation. The use of aircraft by European nations in World War I resulted in concern that the U.S. was lagging in aviation developments. This lead to an act of the I') U.S. Congress in 1915 that established the National Advisory Committee for Aeronautics (NACA) with the 40 VIRGINIA JOURNAL OF SCIENCE charge to conduct aerodynamic research. The research began at Langley Field, VA in the early 1920's. Over the years this research has transformed low-speed, wood and fabric, propeller-driven airplanes into high speed, all-metal, jet-propelled airplanes. Jet and rocket propulsion enhanced the fields of supersonic and hypersonic aerodynamic flight and provided for access to space. In July 1955 the White House announced plans to launch an earth-orbiting satellite. Before this was done, however, the Soviet Union successfully launched Sputnik, the world's first artificial satellite in October 1957. This event caused concern that the U.S was lagging in the 'space race' and lead directly to the establishment of the National Aeronautics and Space Administration (NASA) in July 1958. The nucleus of the NASA was the existing NACA with the charge expanded to include space research. The skilled researchers at NASA-Langley have continued to provide improvements in aircraft developments and now contribute to the development of spacecraft as well. Agriculture, Forestry and Aquaculture Science THE EFFECT OF LARGEMOUTH BASS PREDATORS ON GROWTH AND FEEDING IN CHANNEL CATFISH. Michael L. Fine & Mark S. Mayo Dept. of Biol., VCU, Richmond, VA 23284-2012 and Edward N. Sismour & Scott H. Newton, VSU Agricultural Research Station, Petersburg, Virginia 23806. We examined the effects of largemouth bass predators on growth and feeding in channel catfish. Eight 7 5 gal tanks were divided in half with a plastic mesh, and 10 catfish were placed on the right side of each tank. The left sides were empty in four tanks (controls) or contained a largemouth bass predator (experimentals) in the other four. Bass were typically fed a channel catfish twice a week, and the experiment ran for 3 months. We measured catfish total length, weight and condition factor (W /L) to determine growth and recorded the number of pellets eaten, the time to eat 10 pellets, and catfish movement using a nonparametric scale from O to 3. Catfish grew significantly in both treatments, but weight and condition factor were higher in control fish than in experimentals. Control fish also ate twice as many pellets per minute and consumed more pellets than experimentals. Finally, control fish exhibited continuous movement, but experimentals typically remained stationary with low amplitude tail fluttering and opercular movements. When bass were fed a catfish, movement further decreased. Opercular movement stopped for about 15 sec after a latency of 24 sec, suggesting a chemical cue from catfish predation. Therefore, proximity of largemouth bass suppresses growth, feeding rate, amount of food consumed, and movement of channel catfish. Not only can bass predators affect survival of recently stocked catfish, they can retard the time it takes them to grow to a nonsusceptible size. USING CYTOCHROME B TO DETERMINE SPECIES IN MIXED MEAT SAMPLES. Altamarie Woods & Brian L. Sayre, Dept. of Biology, Virginia State