We've made a near perfect one (tail) for critical measurement of wind direction. We call it Quick 1 because it has

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2 We've made a near perfect one (tail) for critical measurement of wind direction. We call it Quick 1 because it has a distance constant of 2.5 feet and a damping ratio of 0.6. Overshoot is minimized and oscillation practically damped out. Result: every tail movement has a meaning you can measure... wind direction records are more precise, more accurate and easier to analyze than ever before. THEORETICAL TAIL Quick 1 was born in theory. Our research staff made a thorough study* to determine what the geometrical and aerodynamic properties of a wind vane must be to obtain a desired distance constant and damping ratio. In this study it was found that damping ratio, is proportional to the arm length, r v ; the tail planform area, A; the slope of the lift curve of the tail, a; the mass of the tail, Mv; and the mass of the arm, Mb; by the following approximation, where Ki and Kz are constants: (1), f rvaa 1 % ARM Av Vz {C } f Cf) b TAIL PLANFORM AREA C+ TIP CHORD Cr== ROOT CHORD b ** SPAN QUARTER CHORD LOW MASS To get a high damping ratio (see (1) above) the tail must be as light as possible. Our problem was to find a light material that was strong enough to be extended in a high aspect-ratio shape. This we finally accomplished by combining two materials: a foam plastic core bonded within an aluminum skin. With this construction we produced a tail for Quick 1 with an aspect ratio of 6. It is so light that the entire vane weighs under five ounces. Yet, it is rugged enough to withstand hurricane winds. For increased strength, the tail is slightly tapered from the root to the tip. This reduces the bending moment and places the load center nearer the supporting arm. OPTIMUM ARM Since both the damping ratio and distance constant are functions of the arm length (See (1) and (2)) this dimension is of great importance. The arm length had to be as long as possible on the tail side of the axis of rotation and as short as possible on the balancing-mass side. Of course, here again we were faced with the limitations of materials and with keeping the mass of the vane to a minimum. After a great deal of engineering and testing we arrived at the optimum arm lengths. The arm itself is constructed of a rugged aluminum alloy and the balancing mass is of stainless steel. These are the basic characteristics which combine to make Quick 1 the optimum tail for sensing micro winds at the earth's surface. And it's rugged... designed, tested and guaranteed to perform to specification in extreme environments with temperatures from 40 to -f 140 F and winds to 90 miles per hour. Quick 1 is thoroughly tested in our own wind tunnel to assure performance to its extraordinary specifications. The results of a typical wind tunnel test of Quick One's dynamic response are shown in following data: It was also found that the distance constant, D, of a vane is a function of the damping ratio and the length of the arm. This function is expressed in the following (2) definition: D - rv REAL TAIL ~ ~ With this theory in hand, we set out to make a rugged tail with a damping ratio of 0.6 and a distance constant of 2.5 feet. To get this order of performance, it was clear from theory that we needed a tail with very high lift and tow mass. HIGH ASPECT RATIO From aerodynamic principles, and from field and wind tunnel studies of many tail foil shapes, it was established that square-like shapes (low aspect ratio) have poorer lift coefficients than tall, narrow shapes (high aspect ratio). In fact, theoretically, the taller and narrower a tail foil is, the higher its lift coefficient. However, this theory is application limited by the materials one can use in tail construction. (We've got a room full of rejected tails to prove it.) 0 Time (The damping ratio is derived from these data in the manner: I = { 1 + [7r/ln(X,/X2]2 j n. following in this case the derived damping ratio is ) Quick 1 is available now with the Beckman & Whitley WS101 Wind System. Or it can be purchased as standard equipment for the Beckman & Whitley wind systems you are now using. For further information write Meteorological Instrument Applications Department a subsidiary of TECHNICAL SAN CARLOS, CALIFORNIA high aspect ratio } OPERATIONS inc. M P H O N E : C O D E 4-15 * Theoretical Analysis of Wind Vanes; John Corcoran August Send for your copy.

3 Distribution of Weather Charts by MUFAX To meet High Speed requirements Transmitters and Receivers arranged for 480 r.p.m. operation are available. D-649 Chart Recorder. The latest automatic versions of this recorder start and stop, select helix speed and I. of C. on receipt of the appropriate transmitted control signals. K-156 F.S.K./A.M. Converter. Used in conjunction with any good quality communications receiver, enables recorders to operate from F.S.K. Radio transmissions. K-150 Transmitter is arranged to meet the demands of an automatic system, and is suitable for 22in x 18in charts. Also available is the D-990 Transmitter for charts of up to 44in x 18in. D-944 Tape Recorder. Stores signal on tape for onward transmission under favourable radio conditions, or as lines become available. More information on the above facsimile chart equipment is given in the new Muirhead brochure "Mufax Weatherchart Transmitting & Receiving Equipment". Copies are available on request. MUIRHEAD PRECISION ELECTRICAL INSTRUMENTS MUIRHEAD INSTRUMENTS INC., 1101 Bristol Road, Mountainside, New Jersey, U.S.A. Telephone: Code 201, No MUIRHEAD & CO. LIMITED, Beckenham, Kent, England. Telephone: Beckenham 4888 MUIRHEAD INSTRUMENTS LTD., Stratford, Ontario, Canada. Telephone:

4 AMERICAN METEOROLOGICAL SOCIETY Corporation Members Aerometric Research, Inc. Air Transport Association of America Alden Electronic and Impulse Recording Equipment Company Aluminum Company of Canada, Limited American Airlines, Inc. K. R. Amtmann, S.A. ARACON Geophysics Company, a Division of Allied Research Associates, Inc. Astronomisches Institut der Universitat Tubingen Atlantic Research Corporation AVCO Research and Advanced Development Division Baltimore Gas and Electric Company Barnes Engineering Company, Instrument Division Beckman & Whitley, Inc. Belfort Instrument Company The Bendix Corporation, Friez Instrument Division The Boeing Company, Transport Division E. Bollay Associates, Inc. Budd Electronics, Incorporated California Computer Products Cardion Electronics, Inc. Centro Meteorologico Mendoza Civil Air Transport, Incorporated Climet Instruments, Inc. Colorado State University, Department of Atmospheric Science Control Equipment Corporation James M. Cook Co. Cornell Aeronautical Laboratory, Inc. Crop-Hail Insurance Actuarial Association Crosley Broadcasting Corporation Danforth/White, Division of the Eastern Company Dewey and Almy Chemical Company, Division of W. R. Grace & Co. Douglas Aircraft Company, Inc. Eastern Airlines, Inc. The Eppley Laboratory, Incorporated Ess Gee, Inc. Florida State University, Department of Meteorology Flow Corporation The Franklin Institute of the State of Pennsylvania General Dynamics/Pomona General Electric Company, Spacecraft Department General Time Corporation Geophysics Corporation of America Harvard University, Blue Hill Observatory Hogan Faximile Corporation W. E. Howell Associates, Inc. Impulsphysik Intermountain Weather, Inc. International Business Machines Corporation International Telephone & Telegraph Corp. Iranian Meteorological Department Kaysam Corporation of America KTBC Radio and Television Lear Siegler Inc. Arthur D. Little, Inc. Litton Systems, Inc., Applied Science Division Lockheed-California Company Lockheed Missiles and Space Co. The Marquardt Corporation Martin Company, Baltimore Division Martin Company, Denver Division Massachusetts Institute of Technology, Department of Meteorology Melpar, Inc. Meteorology Research, Inc. The Microcard Corporation Minneapolis-Honeywell Regulator Company The Mitre Corporation Motorola, Inc., Systems Research Laboratory Muirhead Instruments, Inc. Murray and Trettel, Consulting Meteorologists National Center for Atmospheric Research National Weather Forecasting Corporation National Weather Institute, Inc. New York University, Department of Meteorology and Oceanography North American Weather Consultants Northeast Weather Service Oklahoma Television Corporation OPTOmechanisms Incorporated Pan American World Airways, Inc. Radio Corporation of America, Astro-Electronic Products Division Republic Aviation Corporation Rocket Power, Inc. Rutgers University, College of Agriculture, Department of Meteorology Saint Louis University, Institute of Technology Sandia Corporation G. T. Schjeldahl Company Science Associates Selenia S.P.A. Servico Meteorologico de Mocambique Sheffield University Library Sierra Research Corporation Sperry Rand Research Center SWISSAIR, Swiss Air Transport Company, Ltd. System Development Corporation Taylor Instrument Companies Technical Operations, Inc. Texas A&M Research Foundation, Department of Oceanography and Meteorology Time & Weather, Incorporated Trans World Airlines The Travelers Insurance Company The Travelers Research Center, Inc. United Air Lines United Aircraft Corporation United Gas Corporation University of Arizona, Institute of Atmospheric Physics University of California, Los Angeles, Department of Meteorology University of Chicago, Department of the Geophysical Sciences University of Michigan, Department of Meteorology and Oceanography University of Michigan, High Altitude Engineering Laboratory University of Nevada, Desert Research Institute University of Washington, Department of Atmospheric Sciences Edward L. A. Wagner, Weather Consultant Weather Corporation of America Weather Engineers, Inc. Weather Routing, Inc. Westrex Company, a Division of Litton Systems, Inc. WTVT Television

5 The BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY is the official organ of the Society, devoted to editorials, survey articles, professional and membership news, announcements, and Society activities. Editing and publishing are under the direction of Kenneth C. Spengler, Executive Secretary. Members are encouraged to send to the Society information which they wish to be considered for publication. Published monthly at Prince and Lemon Streets, Lancaster, Pa Second-class postage paid at Lancaster, Pa. Address all business communications, purchase orders and inquiries regarding the Society to the Executive Secretary, 45 Beacon Street, Boston, Mass technical editor James S. Sandberg news editor E. Ruth Anderson assistant technical editor Carmela A. Poce Cover photograph: Smoke plume from 420-ft instrumented tower at Brookhaven National Laboratory, Upton, N. Y., illustrates turbulence studies whose Soviet counterparts are surveyed in the lead article. Photo courtesy of Brookhaven National Laboratory. volume 45, number 2, February 1964 articles recent Soviet research in atmospheric turbulence Southern Hemisphere weather maps for the International Geophysical Year conference summary conference on the present-day aspects in the atmospheric sciences and oceanography of solar and terrestrial radiative energy transfer 80 A. K. Blackadar and H. A. Panofsky 88 J. J. Taljaard and H. van Loon 96 A. J. Drummond and A. R. Karoli correspondence tropical meteorology conference 104 W. H. Portig more on tropical meteorology 104 Donald C. Gaby House of bill 8708 Representatives report of Committee Cloud Physics, AMS on 116 minutes of the council 122 election results 87 announcements 95 reviews 105 news and notes 107 news from our chapters 112 secretary's letter to chapters 115 about our members 118 at AMS headquarters 123 necrology 124 meetings of the AMS 126 professional directory 130