In-flight load testing of advanced shuttle thermal protection systems

NASA Ames Research Center has conducted in-flight airload testing of some advanced thermal protection systems (TPS) at the Dryden Flight Research Center. The two flexible TPS materials tested, felt reusable surface insulation (FRSI) and advanced flexible reusable surface insulation (AFRSI), are currently certified for use on the Shuttle orbiter. The objectives of the flight tests were to evaluate the performance of FRSI and AFRSI at simulated launch airloads and to provide a data base for future advanced TPS flight tests. Five TPS configurations were evaluated in a flow field which was representative of relatively flat areas without secondary flows. The TPS materials were placed on a fin, the Flight Test fixture (FTF), that is attached to the underside of the fuselage of an F-104 aircraft. This paper describes the test approach and techniques used and presents the results of the advanced TPS flight test. There were no failures noted during post-flight inspections of the TPS materials which were exposed to airloads 40 percent higher than the design launch airloads

The Benefits of Being a Suicidal Curmudgeon: Emil Cioran on Killing Yourself

Emil Cioran offers novel arguments against suicide. He assumes a meaningless world. But in such a world, he argues, suicide and death would be equally as meaningless as life or anything else. Suicide and death are as cumbersome and useless as meaning and life. Yet Cioran also argues that we should contemplate suicide to live better lives. By contemplating suicide, we confront the deep suffering inherent in existence. This humbles us enough to allow us to change even the deepest aspects of ourselves. Yet it also reminds us that our peculiar human ability—being able to contemplate suicide—sets us above anything else in nature or in the heavens. This paper assembles and defends a view of suicide written about in Cioran’s aphorisms and essays

Techniques used in the F-14 variable-sweep transition flight experiment

This paper discusses and evaluates the test measurement techniques used to determine the laminar-to-turbulent boundary layer transition location in the F-14 variable-sweep transition flight experiment (VSTFE). The main objective of the VSTFE was to determine the effects of wing sweep on the laminar-to-turbulent transition location at conditions representative of transport aircraft. Four methods were used to determine the transition location: (1) a hot-film anemometer system; (2) two boundary-layer rakes; (3) surface pitot tubes; and (4) liquid crystals for flow visualization. Of the four methods, the hot-film anemometer system was the most reliable indicator of transition

Effects of Wing Sweep on In-flight Boundary-layer Transition for a Laminar Flow Wing at Mach Numbers from 0.60 to 0.79

The variable sweep transition flight experiment (VSTFE) was conducted on an F-14A variable sweep wing fighter to examine the effect of wing sweep on natural boundary layer transition. Nearly full span upper surface gloves, extending to 60 percent chord, were attached to the F-14 aircraft's wings. The results are presented of the glove 2 flight tests. Glove 2 had an airfoil shape designed for natural laminar flow at a wing sweep of 20 deg. Sample pressure distributions and transition locations are presented with the complete results tabulated in a database. Data were obtained at wing sweeps of 15, 20, 25, 30, and 35 deg, at Mach numbers ranging from 0.60 to 0.79, and at altitudes ranging from 10,000 to 35,000 ft. Results show that a substantial amount of laminar flow was maintained at all the wing sweeps evaluated. The maximum transition Reynolds number obtained was 18.6 x 10(exp 6) at 15 deg of wing sweep, Mach 0.75, and at an altitude of 10,000 ft

Effects of Wing Sweep on Boundary-layer Transition for a Smooth F-14A Wing at Mach Numbers from 0.700 to 0.825

The results are discussed of the variable sweep transition flight experiment (VSTFE). The VSTFE was a natural laminar flow experiment flown on the swing wing F-14A aircraft. The main objective of the VSTFE was to determine the effects of wing sweep on boundary layer transition at conditions representative of transport aircraft. The experiment included the flight testing of two laminar flow wing gloves. Glove 1 was a cleanup of the existing F-14A wing. Glove 2, not discussed herein, was designed to provide favorable pressure distributions for natural laminar flow at Mach number (M) 0.700. The transition locations presented for glove 1 were determined primarily by using hot film sensors. Boundary layer rake data was provided as a supplement. Transition data were obtained for leading edge wing sweeps of 15, 20, 25, 30, and 35 degs, with Mach numbers ranging from 0.700 to 0.825, and altitudes ranging from 10,000 to 35,000 ft. Results show that a substantial amount of laminar flow was maintained at all the wing sweeps evaluated. The maximum transition Reynolds number of 13.7 x 10(exp 6) was obtained for the condition of 15 deg of sweep, M = 0.800, and an altitude of 20,000 ft

Expresión de receptores CB1 en corteza prefrontal y su relación con el nivel de ansiedad en ratones BALB/c suplementados con edulcorantes no nutritivos

Tesis de Licenciatura en Médico CirujanoEl consumo de edulcorantes ha sido empleado como tratamiento co-adyuvante para enfermedades crónicas no transmisibles, incluyendo la diabetes, sobrepeso, obesidad y síndrome metabólico. Sin embargo, en la actualidad, el consumo de estos compuestos se ha extendido a la población general, debido a su incorporación en una gran variedad de alimentos y bebidas para consumo humano. Por lo tanto, es importante conocer sus efectos sobre la salud, ya sean benéficos o perjudiciales. A pesar de que los edulcorantes comerciales son considerados como inocuos, existe evidencia de que su consumo frecuente y crónico puede tener efectos adversos sobre diferentes sistemas corporales, por lo que es necesario determinar las posibles consecuencias que estos aditivos alimentarios tienen en la salud humana. Los endocanabinoides son sustancias derivadas de ácidos grasos que provienen de la remodelación de la membrana celular, cuya producción y liberación ocurren “a demanda”, generando un estado tónico en sus niveles. Actualmente, se reconoce su importancia en la regulación del metabolismo energético. Se ha demostrado que el consumo de la llamada “dieta de cafetería o hipercalórica” se asocia con cambios en los niveles de ansiedad y de forma independiente, con cambios en las funciones del sistema de endocanabinoides; no obstante, los mecanismos que relacionan ambos sistemas aún no se conocen claramente. El propósito de este proyecto fue determinar el efecto del consumo frecuente de un edulcorante comercial (glucósidos de esteviol) sobre la expresión de receptores CB1 del sistema endocannabinoide en el tejido encefálico y su relación con el nivel de ansiedad en un modelo murino. Con este propósito, se utilizaron un total de 12 ratones hembras de la cepa BALB/c, divididos en 3 grupos experimentales, cada uno integrado por 4 ratones, respectivamente. Los animales fueron suplementados durante 6 semanas con sacarosa o con glucósidos de esteviol, además de un grupo control sin suplementación. Durante el proceso se analizó el comportamiento de ansiedad en los animales experimentales a través de prueba de labariento elevado en cruz y prueba de caja oscura, posteriormente, al completarse el tiempo establecido como tratamiento, se obtuvieron cortes histológicos del cerebro, para identificar la expresión del receptor para endocanabinoides CB1. Tras el análisis de las variables deseadas, no se encontró una diferencia significativa en la expresión del receptor CB1 ni en las pruebas de ansiedad dentro de los grupos experimentales, por lo cual, con base en los resultados preliminares obtenidos, se concluye que las suplementaciones con los edulcorantes utilizados no inducen aumento en los niveles de ansiedad ni aumento significativo en la expresión del receptor CB1 para endocanabinoides entre los grupos estudiados.N/

UAS in the NAS: Survey Responses by ATC, Manned Aircraft Pilots, and UAS Pilots

NASA currently is working with industry and the Federal Aviation Administration (FAA) to establish future requirements for Unmanned Aircraft Systems (UAS) flying in the National Airspace System (NAS). To work these issues NASA has established a multi-center UAS Integration in the NAS project. In order to establish Ground Control Station requirements for UAS, the perspective of each of the major players in NAS operations was desired. Three on-line surveys were administered that focused on Air Traffic Controllers (ATC), pilots of manned aircraft, and pilots of UAS. Follow-up telephone interviews were conducted with some survey respondents. The survey questions addressed UAS control, navigation, and communications from the perspective of small and large unmanned aircraft. Questions also addressed issues of UAS equipage, especially with regard to sense and avoid capabilities. From the ATC and military ATC perspective, of particular interest is how mixed-operations (manned/UAS) have worked in the past and the role of aircraft equipage. Knowledge gained from this information is expected to assist the NASA UAS in the NAS project in directing research foci thus assisting the FAA in the development of rules, regulations, and policies related to UAS in the NAS

UAS in the NAS: Survey Responses by ATC, Manned Aircraft Pilots, and UAS Pilots

NASA currently is working with industry and the Federal Aviation Administration (FAA) to establish future requirements for Unmanned Aircraft Systems (UAS) flying in the National Airspace System (NAS). To work these issues NASA has established a multi-center "UAS Integration in the NAS" project. In order to establish Ground Control Station requirements for UAS, the perspective of each of the major players in NAS operations was desired. Three on-line surveys were administered that focused on Air Traffic Controllers (ATC), pilots of manned aircraft, and pilots of UAS. Follow-up telephone interviews were conducted with some survey respondents. The survey questions addressed UAS control, navigation, and communications from the perspective of small and large unmanned aircraft. Questions also addressed issues of UAS equipage, especially with regard to sense and avoid capabilities. From the civilian ATC and military ATC perspectives, of particular interest are how mixed operations (manned / UAS) have worked in the past and the role of aircraft equipage. Knowledge gained from this information is expected to assist the NASA UAS Integration in the NAS project in directing research foci thus assisting the FAA in the development of rules, regulations, and policies related to UAS in the NAS