Volume 16 No 1 Feb 1965.pdf - Lakes Gliding Club

''The perspective appearance of thingsto him was very remarkable. The lowestbed of vapour that first appeared ascloud was pure white. in detachedfleeces, increasing as they rose; they presentlycoalesced, and formed, as he expressesit, a sea of cotton, tufting hereand there by the action of the air in theundisturbed part of the clouds. Thewhole became an extended white floor ofcloud, the upper surface being smoothand even. Above this white floor he observed.at great and unequal distances, avast assemblage of thunder-clouds. eachparcel consisting of whole acres in thedensest form: he compares their formand appearance to the smoke of piecesof ordnance, which had consolidated asit were into masses of snow, and penetratedthrough the upper surface ofwhite floor of the common clouds. thereremaining visible and at rest. Someclouds had motions in slow and variousdirections forming an appearance trulystupendous and majestic."Later in the account:-"In the course of the balloon's tract itwas much affected by the water (a circumstanceobserved in former aerialvoyages). At one time the direction ofthe balloon kept continually over thewater, going directly towards the sea, somuch so all to endanger the aeronaut:the mouth of the balloon was openedand he in two minutes descended into anunder-current blowing from the sea."DUST DEVIL ON SEA-BREEZE FRONTWHEN a "very well-developed" dustwhirl tracked across ldris Airport,16 miles south 01 Tripoli. on 31st May,1964, its centre moved directly over thecontrol tower and meteorological officearea, breaking a window, throwing radioequipment off a table. and making "anoise like a small explosion".The dust whirl was estimated to bemoving at about 10 kts.; its base wasabout SO yards in diameter and its top,estimated to be at about 2,000 ft., hada diameter of about 2S0 yards. It hadcome across mainly cultivated land sodid not contain much dust. but a largenumber of pieces of paper and vegetationwere "circling cyclonically at allheights". As it passed., the met. officebarograph showed an instantaneous falland rise of 35 mb.This was the only dust whirl seen thatday. As it passed, the north to northeastsea breeze penetrated to Idris, itsspeed being 10 kt. initially, increasinglater to 15 kt.J. B. McGinnigle, who describes theevent in the Meteorological Magazinefor Oct., 1964 (Vol. 93, pp. 313-6), comesto this conclusion:-"The combination of the very unstableair mass, large positive energy area (asshown on the tephigram) and very highair and ground temperatures. furtherallied to the marked horizontal convergenceof the sea-breeze front, would behighly conducive to the formation of avigorous vortex which would developon the front as a wave depression. Thevortex would move along the sea-breezefront with the direction of the wind inthe? lower levels and the circulationwould probably be maintained to afew thousand feet. The Wheelus Field(upper air) ascent gives the wind at2.000 ft. at this time as 290·, 8 kL It istherefore suggested that this very largedust whirl was a small vigorous wavedepression on the sea-breeze front.OBITUARYANGUS MACAULAYHE Aberdeen Gliding Club has suffereda very sad loss with the deathTof their C.P.I. Angus Macaulay, whodied on 28th November after a shortillness. Angus, who was 40, served forsome years ~s a pilot with the R.A.F.,where he gained flying experience onmany types 01 aircraft. When he returned56to civilian life he joined our dub andsoon beeame an instructor, being appointedas C.P.I. in 1961. His kind natureand understanding of pupils' difficultiesbas helped so many of us. He was alsoresponsible for our Tug aircraft, whichhe organized with that keen efficiencywhich was so typical of him.We shall all miss him very much.He leaves a wife and three youngchildren. J. P. W.