evidence is scanty, because it comes fromtbe rare wave-like "motber of pearl"clouds, which probably form only whenthe air at that height is abnormallymoist, and anyway can only be seenwhen they are in sunlight and the groundbelow is in darkness. But there seems noreason to believe waves are not presentat other times too. If one of the manystratosphere sailplane projects is evercompleted, we may get further evidence.For the rest, two features of Dr. R. S.Scorer's wave theory are omitted. Instating that a wind sbear helps the formationof waves. he said that this is truenot only when the wind increases withheight, but also when it decreases withheight; in fact, one of the most notablewave flights of the R.AF. PennineWave project was made when the winddecreased with height and the Met. Officetold them there would be no waves thatday. Also, Dick Scorer believes that theBernoulIi effect, according to which pressuredecreases as air velocity increases,nas a greater influence on wave formationthan the "gravity wave" effect mentionedin para. 2.1 of the Appendix;however, as no expert seems able toexplain the working of the pressure{velocity effect in plain English, its absencehere is not surprising.The only otber point on which moremight have been said is the normaldowncurrent to leeward of a mountain:this nearly brought the 1933 MountEverest fliers to grief because they hadbeen given a "safety height" which theycouldn't reach. This downcurrent is indeedmentioned in the text. but both thediagrams in the circular only depict it aspart of the wave system, not as independentof any waves.In summary. this circular maintainsthe conception that there is a "safetyheight" from which a pilot can descendthrough a downcurrent region withouthitting anything before he comes to theend of it. To this old-standing conceptionit adds the new one that safetyheights vary according to circumstances,though in such a way that tbey can stillbe calculated if enough is known aboutthe terrain below. finally, there isspecific advice on how to escape fr.oO?- adowDcurrent - a welcome admissIontbat it is not enough to know yoursafety height. A. E. S.28ACCELEROMETER 35'· p&p 3/6Ex. LA.F. Kolvin Hug~•• TypeKB 482/01 in excellent u".sedcondition. St.nd.rd rh,.. pointertype ..irh inlegf.1 ',.nsport.tion~d. end Iron' ,.,.1 knob. tt.ngecoven ·451 to .l2g.BROTHERSPILOT'S KNEE PADACh".II.,. R..A.F. pe.ft.f" PilotsInlefceptor Plolter Mk. I Consisfsof lightw"9ht anodised atul'llJl·in"'''' frame sheped 10 fit k"..wilh adjusl,bl. .slic.tedquid-,et.se slraps. Hingedplastic wriling pad on met••tre,," wilh integral peflcitholder opens to rev_in•• cher' COllnpa,t.-n:t.nd .djuJt.bl. plasticse.I... Suppljed wi'~two coIltP.rt ... entcenvu hotd.lt.LIMITEDS2 TOTTENHAH COURT ROAD. LONDON WI.PHONE LAN(h~m. OI41.Hrs9-6.Thurs.9-I.AnQl Sat..TOW ROPESFor sale: Nylon Tow Ropeslength 150 It., circumference i",3·srtand, complete with Ottfur. rings each end.Price: £".Os.Od. eachexcluding carriageREMINDER TO CLUBSHOLDING GLIDING COURSESAb Initio pupils may need thefollowing books:-Elementary <strong>Gliding</strong>Price: 5f·d. plus 6d. postageLaws and Rules for Glider PilotsPrice: 2f6d. plus 6d. postageTHE BRITISH GLIDINGASSOCIATIONArtUI.ry Mansions,75, Vlctorica St,.et,London, S.W.1.
IT wasn't just having to get used to atrailer~the car was something of achange too. An aged and irascible cow,of a noble and now extinct line; and incomparison to the delicate manoeuvrabilityof the Sprite I'd been used to,she felt like a rusty tank.And then, of course, there was thetrailer, all 30 miles of it-I beg yourpardon-feet. At least it was no widerthan the car, and comparatively light,but the prospect of having to cope withit-and in public at that-'--appalled me.My first introduction to the businesswas relatively easy, apart from havingto hitch the trailer on to the noble cowby myself, which turned out simpler thanI'd expected, since by sheer luck I'dplaced the car in exactly the right spotto lower the hitch on to the ball.Hanno and 999 had landed only 10miles away, but between us lay the fullsurge of a town's rush-hour traffic. Inegotiated the airfield gate without takinga post with me, and prepared for thecha{)s to come. It was just as well that Ihad forgotten to put the number-plateon the back-I'm sure a lot of peoplewould dearly have loved to report mefor everything from nearly taking thecorner of a house with me, to holdingup all the traffic in three directions atonce.By the time I eased the noble cow andcontraption on to the main road I wasnear to being a total wreck-I personally,that is, not the trailer.I found 999 without any difficulty; shewas conveniently parked by the road.Bursting with pride at my remarkableefficiency, I s.lid alongside and wahedsmugly for the well-deserved praise dueto me. Hanno slanted an eye at the towbarand then at me. "Next time, try lockingthe hitch in place before you start,"he suggested.I deflated rapidly to knee-higb-to-agnatsize, and watched his competentsupervision of two worshipful yokels dismantlingand stowing 999.On the return trip Hanno graciouslyallowed me to drive. 999 hung behind,heavy as my sense of responsibility."Come on, you can go faster tbanthat," urged Hauno."I can't-she keeps yawing.""Then you're just not handling the carproperly!"I gritted my teeth and said nothing.The noble cow wallowed down the road,trailer trundling spongily. "I think I'dbetter drive," said Hanno finnly.Cringing with humility, I changedplaces with him.We continued at a fairly smart pace,when suddenly the trailer slewed acrossthe road, heaving the car into a series ofviolent metronomic yaws. Hanno'sknuckles gleamed whitely on the wheel,and we waltzed gradually to a standstill."I think I'd better check the tyre pressure,"he said.It wasn't exactly necessary., being alltoo obvious that one tyre was very tiredindeed. Hanno made no further mentionof my inefficiency on the way home.The next occasion provided no pitfalls;a long haul to Moreton and some difficultyfinding 999. I spent ages tackingin the dark across a one-time airfield,29
- Page 1 and 2: SA LP A&GLIDIGFebruary - March 1965
- Page 3 and 4: SAILPLANE& GLIDINGOFFICIAL ORGAN OF
- Page 5 and 6: 1965 WORLD G,LIDINGCHAMPIONSHIPSHE
- Page 7 and 8: FRED SLINGSBY'S RETIREMENTANY are t
- Page 9 and 10: D-34(o)D·36Polyt 3Kria7
- Page 11 and 12: dead into sun, and the haze made VI
- Page 13 and 14: its normal position lies very near
- Page 15 and 16: well that you should understand how
- Page 17 and 18: TESTING A SOVIET DISCOPLANEBy V. IV
- Page 19 and 20: cursed. The designer looked despond
- Page 21 and 22: SECOND NEW ZEALAND CHAMPIONSHIPSHOO
- Page 23 and 24: •Official rest day.three pilots a
- Page 25 and 26: 1965 COURSES AT LASHAMHE 196'5 cour
- Page 27 and 28: LEE WAVE uGEN" FOR AEROPLANE PILOTS
- Page 29: of the Sheffield gale. The other is
- Page 33 and 34: change, my man," I sa.id grandly, a
- Page 35 and 36: outes. It's all a snare and a delus
- Page 37 and 38: electrical horizons 'have complete
- Page 39 and 40: Finally, the turn-and-slip indicato
- Page 41 and 42: 1964 KRONFELD ART EXHIBITION AND196
- Page 43 and 44: Loi61U ;nOrder Pi/or Points 1964 Or
- Page 45 and 46: RHODESIA'S FIRST 500 KILOMETERSBy E
- Page 47 and 48: 2-3~ en154.2'-'5-0 IDID6 0 en~c7
- Page 49 and 50: JIy30-40506"0 70 8"0 9"0I I I I, eq
- Page 51 and 52: BRITISH GLIDING ASSOCIATION NEWSCHI
- Page 53 and 54: wings ar~ lewel. If you can do this
- Page 55 and 56: T" T I G" I. 1.111 Y 11 74'0THEKRON
- Page 57 and 58: as the squall struck us, about half
- Page 59 and 60: about 3,000 feet, at which altitude
- Page 61 and 62: TRUE FLIGHT-A FABLEBy M. BIRDOOKING
- Page 63 and 64: iBOOK REVIEW•Great Flights and Ai
- Page 65 and 66: will go on into the foreseeable fut
- Page 67 and 68: I feel that the home-made winch wil
- Page 69 and 70: FOR SALE (contd.)T.3IB, C. of A. fr
- Page 71 and 72: BLACKPOOL AND FYLDEP"e.~enratioll o
- Page 73 and 74: which we had from the Shaw Slingsby
- Page 75 and 76: able piece ef Club equipment was bu
- Page 77 and 78: And still he wasn't satisfied, this
- Page 79 and 80: As usual, Lasham continues to opera
- Page 81 and 82:
to his usual standard. The surprise
- Page 83 and 84:
Margate before setting off in Sky.)
- Page 85 and 86:
CHEVIOTS (Acklington)SINCE our last
- Page 87 and 88:
a gliding record. He made his first
- Page 89 and 90:
The Boomerang.from a light-weight a
- Page 91 and 92:
The Club's order for a Ka-6 waschan
- Page 93 and 94:
Lindner, of Teek, with 2,434.2. - A
- Page 95 and 96:
A Gliding Holiday io Kentwith the K