Download or read book Development and Calibration of the Forward Scatter Visibility Meter written by H. Stuart Muench and published by . This book was released on 1974 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: A new visibility instrument, the forward scatter visibility meter, has been developed. This report describes the development of the instrument, including the various field tests. Some thirty instruments have been operationally deployed in a network of automatic weather stations near L.G. Hanscom Field in Bedford, Mass. Comparisons between field instruments and transmissometers yield differences of about plus or minus 19 percent. Comparisons with visual observations show differences of plus or minus 34 percent and greater. Analyses of individual cases uncovered difficulties with the response time of observers and with ability to diagnose spatially varying visibility. The accuracy of visibility measurements is assessed and the report concludes by looking at the future of visibility instruments. (Author).
Download or read book Development and Calibration of the Forward Scatter Visibility Meter written by H. Stuart Muench and published by . This book was released on 1974 with total page 37 pages. Available in PDF, EPUB and Kindle. Book excerpt: A new visibility instrument, the forward scatter visibility meter, has been developed. This report describes the development of the instrument, including the various field tests. Some thirty instruments have been operationally deployed in a network of automatic weather stations near L.G. Hanscom Field in Bedford, Mass. Comparisons between field instruments and transmissometers yield differences of about plus or minus 19 percent. Comparisons with visual observations show differences of plus or minus 34 percent and greater. Analyses of individual cases uncovered difficulties with the response time of observers and with ability to diagnose spatially varying visibility. The accuracy of visibility measurements is assessed and the report concludes by looking at the future of visibility instruments. (Author).
Download or read book Tactical Visibility Meter written by Eugene Y. Moroz and published by . This book was released on 1983 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt: Accurate and timely visibility information is required by the Air Weather Service in support of Air Force tactical bare-base operations. The Air Force Geophysics Laboratory (AGGL) undertook a program to develop a tactical visibility meter (TVM) to satisfy this requirement. A prototype meter was designed and fabricated by Wright & Wright, Inc., Oak Bluffs, Mass. The meter measures the atmospheric scattering coefficient in the forward direction. Visibility is inferred from the measurement. The operation of the prototype meter was successfully demonstrated by AFGL in tests conducted at its Weather Test Facility, Otis AFB, Mass. In the next phase of the development, Wright & Wright, Inc., was tasked to design and fabricate a cost-effective preproduction version of the TVM. This report describes the current development, test, and evaluation of the TVM.
Download or read book Air Force Surveys in Geophysics written by and published by . This book was released on 1975 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Instrumentation Papers written by and published by . This book was released on with total page 424 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Preliminary Assessment of an Automated System for Detecting Present Weather written by H. Albert Brown and published by . This book was released on 1979 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: The determination of subjective weather observations through the use of an automated array of weather sensors coupled with a decision tree program was examined through analysis of data gathered at the AFGL Weather Test Facility at Otis AFB, Mass. This report describes the instruments used in the array, the response of the instruments to type of weather observed, and the decision tree programs. Preliminary results indicate that a computer-controlled weather sensor array has potential value in determining objectively those types of weather previously relegated to human responsibility.
Download or read book A Climatological Study of the AFGL Mesonetwork written by H. Albert Brown and published by . This book was released on 1982 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Environmental Research Papers written by and published by . This book was released on with total page 402 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Automated Low cost Weather Observation System ALWOS written by and published by . This book was released on 1982 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt: One of the primary objectives of this program was to design a developmental model ALWOS for the lowest possible cost. Reliability and maintenance costs over the life of the system were considered in addition to the initial purchase and installation costs. To this end, field proven, off the shelf components were used wherever possible throughout the system. Another primary objective was modularity of design. The hardware and software were constructed to allow flexibility in interfacing a variety of sensors or adding additional sensors to measure new parameters. The ALWOS as configured at Dulles Airport is a low-cost and flexible system which can provide an automatic weather observation from the data acquisition, processing and display point of view, with the potential for good long-term system reliability. After a period of familiarization with the equipment and dealing with an assortment of system and sensor problems, the functioning of the system became relatively trouble-free. Evaluation of the ALWOS supports the generally accepted concept that automated, low-cost weather observation systems can indeed perform such a function given suitable sensing devices. (Author).
Download or read book EPA 600 4 written by and published by . This book was released on 1980-02 with total page 314 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Objective Prediction of Fine Scale Variations in Radiation Fog Intensity written by William Richard Tahnk and published by . This book was released on 1975 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: An examination of objective forecast techniques using sensor equivalent visibility to forecast fine scale variations in visibility was conducted with approximately two yr of radiation fog data collected in the AFCRL mesonet-work. Using stepwise screening regression and Regression Estimation of Event Probability (REEP) techniques, the results demonstrated the usefulness of a network of remote sensors around an airfield in objectively predicting short time scale fluctuations of airfield runway visibility. The REEP technique in particular generated exceedance probabilities that display positive skill relative to a conditional climatology model (Markov) of proven validity. Skill by subjective forecasters was also demonstrated using the REEP output as guidance in the generation of short-range forecasts out to one hr. The necessity for additional network stations away from the runway was demonstrated since statistical techniques utilizing runway visibility observations only, when applied to independent data, showed large negative skill relative to the Markov model in contrast to positive skill achieved using 8 network stations of varying distances out to 16 km from the runway.
Download or read book NBS Monograph written by and published by . This book was released on 1959 with total page 374 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Forward Scatter Meter Measurements of Slant Visual Range written by Wayne S. Hering and published by . This book was released on 1978 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: The potential for remote tower measurements of point visibility in the determination of slant range visibility for aircraft landing operations was explored through analysis of data collected at the Air Force Geophysics Laboratory Weather Test Facility at Otis AFB, Massachusetts. This report described initial experiments that deal with an analysis of the small scale variability of extinction coefficient in time and space. Data from two instrumented towers spaced 1500 ft apart were classified for investigation of the horizontal variability of visibility at elevations up to 100 ft and space-time variability for lag periods from 0 to 10 minutes. The preliminary tests give additional evidence that the runway visual range (RVR) measurements alone often are not representative of pilot visibility during approach and touchdown. Remote measurements of visibility using either a 50-ft or 100-ft instrumented tower would add significantly to the real safety of 'see-to-land' operations under conditions of Categories I, II, and IIIa through an improved description of conditions related to airfield visibility. (Author).
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1988 with total page 972 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Variability of Airfield Visibility written by Donald A. Chisholm and published by . This book was released on 1974 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this paper some results are presented concerning temporal and spatial variability of automated visibility measurements along a runway in conjunction with tower measurements. Comparisons are also made with variability statistics drawn from multi-transmissometer systems evaluated for the FAA.
Download or read book The Effect of a Rectangular scaffold Tower on Extinction Coefficients and Winds Measured in Close Proximity to the Tower written by Donald A. Chisholm and published by . This book was released on 1975 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: An examination of observations of extinction coefficients and winds gathered on opposite sides of a rectangular scaffold tower was conducted to determine to what extent the tower structure altered the prevailing characteristics of the atmospheric parameters. Data were gathered over a two-month period during a wide range of conditions (rain, stratus and fog, and unrestricted periods of visibility) and measurements of the variability of the observations were determined. From these studies, it was found that: (1) The tower structure does not adversely affect the prevailing homogeneity of extinction coefficient, (2) wind speed is retarded by about 10% on the lee side of the tower, and (3) wind direction is more variable on the windward side of the tower.
Download or read book Report on Research at AFCRL written by Air Force Cambridge Research Laboratories (U.S.) and published by . This book was released on 1972 with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt:
