TALE OF A TAIL. 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 TALE OF A TAIL 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, f; is proportional to the arm length, rv; 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 K, and K z are constants:. T rvaa IVi (!) ARM A v = y 2 <Ct + C r ) b T A I L PLANFORM AREA Ct TIP CHORD C r - = ROOT C H O R D b =* S P A N 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 definition: (2) ry 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 low 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 i t ) 0 (The Time damping manner: derived ratio is derived damping data in the. following In this case the 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 from these f = { 1 -f [7r/ln(X,/X2]2 } OPERATIONS inc. PHONE: CODE 4-15 ^Theoretical Analysis of Wind Vanes; John Corcoran; August, Send for your copy.

3 No GABLE SHIP "GABLE ENTERPRISE " The new C.S. Cable Enterprise of Cable & Wireless Ltd. is fitted with a Mufax Weather Chart Recorder which keeps the Captain informed of impending weather conditions and enables him to plan cable repair and laying operations accordingly. This is the sixth cable ship of Cable & Wireless to be fitted with a Mufax recorder a tribute to the excellent service these machines give. The top picture shows C.S. Cable Enterprise at her sea trials off the Isle of Arran which took place in July. The lower picture shows the Wireless cabin in which the Mufax Recorder is installed and is shown mounted over the radio receiver. C.S. Enterprise will be based in the Far East and will assist in SEACOM operations the South East Asia link of the commonwealth telephone cable which will be completed between Malaysia, Hong Kong and Australia in MUIRHEAD INSTRUMENTS INC., 1101 Bristol Rd., Mountainside, New Jersey, U.S.A. MUIRHEAD Tel: Code 201, No MUIRHEAD INSTRUMENTS LIMITED, Stratford, Ontario, Canada. Tel: Code 519, No MUIRHEAD & CO. LIMITED, Beckenham, Kent, England. Tel: Beckenham

4 Proceedings 1964 world conference on Radio Meteorology Incorporating the E M weather Radar Conlnretice September 14-18, 1964 Boulder, Colorado Under the sponsorship of the Inter-Union Committee on Radio Meteorology of the International Scientific Radio Union (URSI) and International Union of Geodesy and Geophysics (UGGI), American Meteorological Society, National Bureau of Standards' Central Radio Propagation Laboratory and U. S. Weather Bureau Leading world scientists in the fields of radio and radar meteorology have made contributions on the following subjects: anomalous echoes and angels (9 papers) ; radio climatology (4 papers) ; meteorological effects on propagation (6 papers) ; sferics (6 papers) ; rainfall measurements and drop-size distribution (12 papers) ; scattering and attenuation (9 papers) ; tropospheric and terrain noise radiation (5 papers) ; radio refractive index measurements (7 papers) ; techniques and instrumentation (16 papers) ; hurricanes (5 papers) ; storm structure (10 papers) ; tropospheric propagation, super refraction, scatter propagation (13 papers) ; measurements at optical wavelengths lasers (3 papers). P R I C E : $10 per copy PAGES : 513 S E N D O R D E R S T O : AMERICAN METEOROLOGICAL SOCIETY 45 BEACON STREET, BOSTON, MASS

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 Sccond-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 Carmcla A. Poce editor Cover photograph: Strip of four consecutive APT photographs received from NIMBUS I at Greenbelt, Md., as the satellite passed from south to north near noon on 30 August The Gulf of Venezuela and the Island of Cuba can be clearly seen at the bottom of the picture. Hurricane Cleo is located over Georgia near the center left. At the top, north of the Great Lakes, a massive cloud system is depicted. volume 45, number 11, November 1964 articles the NIMBUS 1 meteorological satellite focus on "INQUA" the International Association for Quaternary Research 684 W. Nordberg and Harry Press 688 J. Murray Mitchell, Jr. AMS organization other activities of the AMS: publications 691 notice to journal contributors 694 minutes of the council 717 correspondence on Soviet cloud physics research 708 V. M. Muchnik reply (to V. M. Muchnik) 708 Louis J. Battan on pressure maxima 708 J. H. Bradley about our corporation members The Franklin Institute 710 program 236th National Meeting of the AMS 695 news and notes 707 reviews 726 necrology 708 at AMS headquarters 730 announcements 714 meetings of the AMS 732 about our members 724 professional directory 734