22 research outputs found
Leading edge curvature based on convective heating Patent
Construction of leading edges of surfaces for aerial vehicles performing from subsonic to above transonic speed
Launch vehicle effluent measurements during the August 20, 1977, Titan 3 launch at Air Force Eastern Test Range
Airborne effluent measurements within the launch cloud and visible and infrared measurements of cloud physical behavior are discussed. Airborne effluent measurements include concentrations of HCl, Cl2, NO, NOX, and particulates as a function of time during each sampling pass through the exhaust cloud. The particle size distribution was measured for each pass through the cloud. Mass concentration as a function of particle diameter was measured over the size range of 0.05- to 25 micron diameter, and particle number density was measured as a function of diameter over a size range of 0.5 to 7.5 micron. Effluent concentrations in the cloud ranged from about 30 ppm several minutes after launch to about 1 to 2 ppm at 100 minutes. Maximum Cl2 concentrations were about 40 to 55 ppb and by 20 minutes were less than 1.0 ppb. A tabulated listing of the airborne data is given in the appendix. Usable cloud imaging data were limited to the first 16 minutes after launch
Stability and control characteristics at transonic speeds of a model of a supersonic target drone with differentially deflected horizontal-tail surfaces
Apollo Saturn 511 effluent measurements from the Apollo 16 launch operations: An experiment
An experiment was performed in conjunction with the Apollo 16 launch to define operational and instrumentational problems associated with launch-vehicle exhaust effluent monitoring. Ground and airborne sampling were performed for CO, CO2, hydrocarbons, and particulates. Sampling systems included filter pads and photometers for particulates and whole-air grab samples for gases. Launch debris was identified in the particulate samples at ground level(taken immediately after launch) and in the airborne measurements (taken 40 to 50 minutes after launch approximately 40 km downwind of the pad). Operational problems were identified and included the need for higher instrumentation mobility and the need for real-time sampling instrumentation as opposed to collection-type samples such as the whole-air grab sample
Instrumentation of sampling aircraft for measurement of launch vehicle effluents
An aircraft was selected and instrumented to measure effluents emitted from large solid propellant rockets during launch activities. The considerations involved in aircraft selection, sampling probes, and instrumentation are discussed with respect to obtaining valid airborne measurements. Discussions of the data acquisition system used, the instrument power system, and operational sampling procedures are included. Representative measurements obtained from an actual rocket launch monitoring activity are also presented
Launch vehicle effluent measurements during the September 5, 1977, Titan 3 launch at Air Force eastern test range
Airborne effluent measurements and cloud physical behavior data are presented. The monitoring program included airborne effluent measurements in situ in the launch cloud, visible and infrared photography of cloud growth and physical behavior, and limited surface collection of rain samples. Effluent measurements included concentrations of HCl, Cl2, NO, nitric oxide, and particles as a function of time in the exhaust cloud. In situ particle mass concentration and number density were measured as a function of time and size in the range of 0.05 micron m to 30 micron m diameter. Measurement results were similar to those of previous launch monitorings. Maximum HCl and nitric oxide concentrations of Cl2 were maximum about 2 minutes after launch and by 10 to 15 minutes had decayed to less than 10 ppb (detection limit). Particle measurements showed most of the particles present to be below about 3-micron m diameter. Postlaunch analyses of collected particle samples showed significant amounts of Al (some cases Cl) from about 3-micron m to 0.04-micron m diameter
Effluent monitoring of the December 10, 1974, Titan 3-E launch at Air Force Eastern Test Range, Florida
Surface and airborne field measurements of the cloud behavior and effluent dispersion from a solid rocket motor launch vehicle are presented. The measurements were obtained as part of a continuing launch vehicle effluent monitoring program to obtain experimental field measurements in order to evaluate a model used to predict launch vehicle environmental impact. Results show that the model tends to overpredict effluent levels
Summary of aircraft results for 1978 southeastern Virginia urban plume measurement study of ozone, nitrogen oxides, and methane
Ozone production was determined from aircraft and surface in situ measurements, as well as from an airborne laser absorption spectrometer. Three aircraft and approximately 10 surface stations provided air-quality data. Extensive meteorological, mixing-layer-height, and ozone-precursor data were also measured. Approximately 50 hrs (9 flight days) of data from the aircraft equipped to monitor ozone, nitrogen oxides, dewpoint temperature, and temperature are presented. In addition, each experiment conducted is discussed
Buffet Tests of an Attack-airplane Model with Emphasis on Analysis of Data from Wind-tunnel Tests
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NACA Research Memorandums
Memorandum presenting the buffet characteristics of a scale model of an attack airplane over a range of Mach numbers. The wing had a modified delta plan form with an NACA 0008 airfoil section at the root and an NACA 0005 airfoil section at the tip, a leading-edge sweep of 41.11 degrees, an aspect ratio of 2.91, and a taper ratio of 0.226. Results regarding the frequency spectrum of bending moment, effect of density on root-mean-square bending moment, system damping coefficients, and buffet input force are provided