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An impulse-momentum analysis was conducted of crash deceleration pulse data from the National Aeronautics and Space Administration (NASA) crash dynamics program on general aviation airplanes and transport crash data available in the literature. The purpose of the analysis was to correlate crash data with flight parameters at impact. In the analysis, assumptions made to simplify the complex crash scenario led to uncoupled equations for the normal and longitudinal floor impulses (product of deceleration and time) in the cabin area of the airplane. Analytical expressions for structural crushing during impact and for the airplane horizontal slide-out were also determined. Good agreement was found between the experimental and analytical data for the general aviation and transport airplanes over a relatively wide range of impact parameters.

Measurements obtained for ground tests on a Twin Otter aircraft show that structureborne noise is a major contributor to the interior noise level. The structureborne source was the propeller blade wake and tip vortex interaction with the wing and contributes at the blade passage frequency and its harmonics.

The ability of modern airplane surfaces to achieve laminar flow has been well-accepted in recent years. Obtaining the maximum benefit of laminar flow for aircraft drag reduction requires maintaining minimum leading-edge contamination. Previously proposed insect contamination prevention methods have proved impractical due to cost, weight, or inconvenience. Past work has shown that insects will not adhere to water-wetted surfaces, but large volumes of water required for protection rendered such a system impractical. This paper presents results of a flight experiment conducted by NASA to evaluate the performance of a porous leading-edge fluid discharge ice protection system operated as an insect contamination protection system. In addition, these flights explored the environmental and atmospheric conditions most suitable for insect accumulation.

This report summarizes the experimental research conducted at the NASA Langley Research Center on general aviation seat and occupant crash response and discusses seat design considerations. Included are typical floor acceleration pulses from general aviation airplane crash tests, the performance of typical general aviation seats in a simulated crash environment, and the performance of prototype energy absorbing (EA) seat designs. Static and dynamic seat testing procedures and test facilities are discussed. Also presented are results from a series of dynamic tests of typical general aviation seats and prototype EA seats.

Landings of the Space Shuttle Orbiter at 200 knot speeds on the rough, grooved Kennedy Space Center runway have encountered greater than anticipated tire wear, which resulted in limiting landings on that runway to crosswinds of 10 knots or less. The excessive wear stems from wear caused during the initial tire touchdown spin-up. Tire spin-up wear tests have been conducted on a simulated KSC runway surface modified by several different techniques in an effort to reduce spin-up wear while retaining adequate wet cornering coefficients for directional control. The runway surface produced by a concrete smoothing machine using cutters spaced 1 3/4 blades per centimeter was found to give adequate wet cornering while limiting spin-up wear to that experienced in spinups on smooth concrete.

A brief history of stall/spin technology for light general aviation airplanes and proposed criteria to describe desirable characteristics of a spin-resistant airplane are presented. Flight tests of a representative light airplane to evaluate compliance with and usefulness of the criteria are presented. The baseline airplane configuration would not meet the spin resistance criteria. Tests of the airplane with a wing leading edge modification to enhance its spin resistance showed compliance with the proposed criteria.