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The gust and draft velocities from records of NACA instruments installed in P-61C airplanes participating in thunderstorm flights at Clinton County Army Air Field, Ohio, from August 13, 1947 to August 15, 1947 are presented.
The gust and draft velocities evaluated from records of NACA instruments installed in P-61C airplanes participating in thunderstorm flights at Clinton County Army Air Field, Ohio, from May 13 to May 29, 1947 are presented.
This report presents the result of tests of a 0.35-scale model of the Bell P-39N-l airplane. Included are the longitudinal-stability and - control characteristics of the airplane as indicated by tests of the model equipped with each of two different sets of elevators. The results indicate good longitudinal stability and control throughout the speed range encounterable in flight. The variation of estimated stick force with speed was less when the model was equipped with elevators constructed to the theoretical design dimensions than when equipped with elevators as built to scale from measurements of the corresponding-parts of the actual airplane. The predicted stick forces required to produce the normal accelerations attainable in flight are within the limits specified by the Army Air Forces.
The gust and draft velocities from records of NACA instruments installed in P-61c airplanes participating in thunderstorm flights at Clinton County Army Air Field, Ohio, from July 12, to July 18, 1947 are presented.
A dynamically similar model of the Army P-38 airplane was tested to determine the best way to land this airplane on the water and to determine its probable ditching performance. The tests consisted of ditching the model at various landing attitudes, flap settings, speeds, weights, and conditions of simulated damage. The model was ditched in calm water from the tank towing carriage and a few ditching were made in both calm and rough water at the outdoor catapult. The performance of the model was determined by making visual observations, by recording lengths of run and time histories of decelerations, and by taking motion pictures of the ditchings.
The results obtained from an evaluation for gust and draft velocities of acceleration and airspeed-altitude records taken by NACA recording instruments installed in P-61c airplanes participating in thunderstorm flights 6, 7, and 8 of July 9, 1946, July 10, 1946, and July 11, 1946, respectively, are presented herein. These data are summarized in tables I and II. In accordance with a recent discussion with a member of the U.S. Weather Bureau staff, the tabulated results for the present flight include in addition to data of the type presented in reference 1, the initial heading of the airplane for each traverse, the pressure altitude at the start of each traverse in increments of 500 feet, and the gust gradient distance when it could be evaluated. The cloud entry and exit times for the present data were taken from motion-picture records of the pilot's instrument panels whenever such records were available while the length fo the traverses in seconds and feet was taken from the airspeed-altitude records. In many cases, however, poor agreement is indicated between the duration of the cloud traverses as obtained from the motion-picture records and from the airspeed-altitude records. This result is believed to be due to camera stoppages, inaccurate spring mechanisms of the clocks, and loss of motion-picture record in exposure or development. With reference to the evaluation of gust data, the nominal threshold was about 2 feet per second. In making gust counts to this threshold, some gusts below that threshold have been included due to limitations of the procedure used. Thus, it will be noted that in some instances gust counts are given in table I although now corresponding gust velocities are listed.
Tables I and II of this report summarize the gust and draft velocity data for thunderstorm flights 31, 32, and 33 of September 5, 1946, September 6, 1946, and September 10, 1946, respectively. These data were evaluated from records of NACA instruments installed in P-61C airplanes and are of the type presented for previous flights. Table III summarizes the readings of a milliammeter which was used in conjunction with other equipment to indicate ambient air temperature during thunderstorm surveys. These data were read from motion-picture records of the instrument and include all cases in which variations in the instrument indications were noted for the present flights.
Tables I and II of the present paper summarize the gust and draft velocity data for thunderstorm-flights 21 and 22 of August 14, 1946 and August 15, 1946, respectively. These data were evaluated from records of NACA airspeed-altitude and acceleration recorders installed in P-61C airplanes and are of the type presented for previous flights. Table III summarizes the readings of a milliammeter which was used in conjunction with other equipment to indicate ambient-air temperature during thunderstorm surveys. These data were read from photo-observer records and include all cases in which variations of the instrument indications were noted for the present flights.
This final report summarizes the progress achieved over the entire 3-year proposal period including two extensions spanning 1 year. These activities include: 1) Preparation for and participation in the NASA 2001 TRACE-P campaign using our airborne tunable diode laser system to acquire measurements of formaldehyde (CH2O); 2) Comprehensive data analysis and data submittal to the NASA archive; 3) Follow up data interpretation working with NASA modelers to place our ambient CH2O measurements into a broader photochemical context; 4) Publication of numerous JGR papers using this data; 5) Extensive follow up laboratory tests on the selectivity and efficiency of our CH20 scrubbing system; and 6) An extensive follow up effort to assess and study the mechanical stability of our entire optical system, particularly the multipass absorption cell, with aircraft changes in cabin pressure.
Chemical and physical aerosol data collected on the DC-8 during TRACE-P were grouped into four sectors based on back trajectories. The four sectors represent long-range transport from the west (WSW), regional circulation over the western Pacific and Southeast Asia (SE Asia), polluted transport from Northern Asia with substantial sea salt at low altitudes (NNW) and a substantial amount of dust (Channel). WSW has generally low mixing ratios at both middle and high altitudes, with the bulk of the aerosol mass due to non-sea-salt water-soluble inorganic species. Low altitude SE Asia also has low mean mixing ratios in general, with the majority of the aerosol mass comprised of non-sea-salts, however, soot is also relatively important m this region. "w had the highest mean sea salt mixing ratios, with the aerosol mass at low altitudes (a km) evenly divided between sea salts, mm-sea-salts, and dust. The highest mean mixing ratios of water-soluble ions and soot were observed at the lowest altitudes (a km) in the Channel sector. The bulk of the aerosol mass exported from Asia emanates h m Channel at both low and midaltitudes, due to the prevalence of dust compared to other sectors. Number densities show enhanced fine particles for Channel and NNW, while their volume distributions are enhanced due to sea salt and dust Low-altitude Channel exhibits the highest condensation nuclei ((34) number densities along with enhanced scattering coefficients, compared to the other sectors. At midaltitudes (2-7 km), low mean CN number densities coupled with a high proportion of nonvolatile particles (265%) observed in polluted sectors (Channel and NNW) are attributed to wet scavenging which removes hygroscopic CN particles. Low single scatter albedo m SE Asia reflects enhanced soot
There were three major tasks and objectives that the Tropospheric Trace Gas and Airborne Measurement Group's (TTGAMG) worked on for different aspects of this grant: 1) Migrate the data acquisition system from HP-UX to Linux, thus reducing future costs as the result of software and operating system (OS) upgrades and improving upon usability as membership in the group changes; 2) Rework the Optical Parametric Oscillator (OPO) cavities. These are the OPOs that are integral to the Georgia Institute of Technology Airborne Laser Induced Fluorescent Experiment (GITALIFE) that the TTGAMG flew on TRACE-P. The objective was to improve upon optimizing the pump laser energy and narrowing the linewidth of the UV wavelength generated by the OPOs; 3) Improve and expand the interactive website on http://tmbk2.eas.gatech.edu by adding 3-D graphing, improve the response time for Joe Surfer Dude, improve performance, usability, and expand the database. If I were to assign a letter grade to each of the above tasks, I would give the TTGAMG two Bs and an A to the tasks listed above.
The techniques for interferometric calibration of the GeoSAR P-Band system are discussed. These techniques are demonstrated using preliminary GeoSAR data.
Hubble Space Telescope near infrared camera and multiobject spectrometer (NICMOS) imaging observations of two nearby young brown dwarfs, DENIS-P J1228.2-1547 and Kelu 1, show that the DENIS object is resolved into two components of nearly equal brightness with a projected separation of 0.275 arcsec.
A comprehensive experimental and theoretical work has been conducted in order to optimize the thermoelectric properties of Si_(80)Ge_(20) materials and reach the goal of a combined figure of merit value of 0.85x10^(-3) K^(-1) averaged over a 600-1000 C temperature range. Improvement for the n-type material has been obtained by determining the optimum amounts of gallium and phosphorus dopants necessary to achieve optimum carrier mobility and concentration. The emphasis is now on the consistent reproducibility of these results through understanding and control of the hot-pressing parameters relating microstructure and composition to the transport properties. The optimum doping level has now been firmly established for p-type materials, and work is concentrating on the reduction in thermal conductivity. BN ultra fine particles have been successfully incorporated into fully dense samples and have resulted in desired improvement of the figure of merit...
High accuracy geodetic solutions at the few ppb level have become fairly standard with data from a global network of P-code Global Positioning System (GPS) receivers. Used as a measurement tool, it has numerous scientific applications including the monitoring of crustal motion, volcanic and post-seismic uplift, co- and post-seismic displacements in fault zones and media delay calibration and monitoring.
The results of a joint experimental and theorectical study concerning elastic electron scattering by laser-excited (sup 138)Ba(....6s6p) (sup 1)P(sub 1) atoms are described.
Experimental cross sections are reported for electron excitation of the allowed 2s (sup 2)S 2p - (sup 2)P transition in C(sup 3+).
Optical emissions in single-collision, beam-beam reactions of fast (3-22 eV translational energy) 0((sup 3) P) atoms with C (sub 2) H (sub 2) have been measured in the wavelength range 300-850 nm.