file which includes the original illustrations4 ,see #egddc-;h4htm or #egddc-;h4zip3 7https3_/_/www4gutenberg4org_/cache_/epu b_/#egddc_/pg#egddc-;images4html7 or 7https3_/_/www4gutenberg4org_/files_/#eg ddc_/egddc-;h4zip7 ,images of the original pages are available through ,internet ,archive4 ,see https3_/_/archive4org_/details_/aviatort heweathe#jj;carpiala ,transcriber's note3 ,text enclosed by underscores is in italics 7italics74 ,illustration3 ,,army ,,airplane ,,gliding ,,to ,,north ,,island ,,over ,u4 ,s4 ,,cruiser 8,,san ,,diego0 ,,the ,,aviator ,,and ,,the ,,weather ,,bureau by ,,ford ,a4 ,,carpenter1 ,,ll4,d4 ,meteorologist ,illustrated with ,photographs and ,charts by the ,author and ,others ,published by the ,san ,diego ,chamber of ,commerce #aiag ,published by permission ,dated ,august #be1 #aiaf ,second edition1 #e1jjj copies ,j4 ,horace ,mc,farland ,company ,mt4 ,pleasant ,press ,harrisburg1 ,pennsylvania ,introductory ,note ,this is a brief but general account of the history of aviation as it is associated with southern ,california1 a description of the ,war ,department school of aviation at ,san ,diego1 a syllabus of the course of lectures delivered there on the subject of practical meteorology as applied to aviation1 a narrative of weather-study from an airplane1 and a recital of subsequent active coperation between the aviators and the ,u4 ,s4 ,weather ,bureau4,a ,a ,it may be remembered that the weather service of the ,united ,states originated with the ,signal ,corps of the ,army and that the ,weather ,bureau was created from it by ,act of ,congress1 ,june1 #ahia1 and made a bureau of the ,u4 ,s4 ,department of ,agriculture4 ,as a former member of the ,signal ,corps the writer enjoyed the renewal of old friendships among the officers at the ,aviation ,school4 ,col4 ,w4 ,a4 ,glassford1 ,signal ,corps1 ,u4 ,s4 ,army1 ,commandant of the ,war ,department ,aviation ,school at ,san ,diego1 kindly read the manuscript of the following pages and the writer gratefully acknowledges his valuable suggestions4 ,much of the material in the following pages was obtained by the writer while detailed as ,lecturer in ,meteorology to the ,signal ,corps1 ,war ,department ,aviation ,school at ,san ,diego1 in #aiae-aiaf1 also when detailed in the same official capacity to the ,u4 ,s4 ,army ,military ,training ,encampment1 ,monterey1 #aiaf2 and at the summer sessions of the ,university of ,california during #aiad-aiaf4 ,,los ,,angeles1 ,,cal41 ,february1 #aiag4 ,to ,j4 ,s4 ,a4 ,table of ,contents ,,chapter ,i ,the ,signal ,corps ,aviation ,school at ,san ,diego1 ,california #g ,,chapter ,,ii ,applied ,meteorology for the ,aviator #aa ,,chapter ,,iii ,weather ,observations from an ,airplane #af ,,chapter ,,iv ,investigating the ,upper ,air #be ,list of ,plates ,figure ,no4 ,page ,army airplane gliding to ,north ,island ,over ,u4 ,s4 ,cruiser 8,san ,diego0 ,frontispiece #a4 ,congressional ,medal awarded ,wright brothers #cc #b4 ,ascent of sounding balloons at ,avalon #cd #c4 ,meteorograph which made the ascent of ,july #bg1 #aiac #ce #d4 ,first flight of airplane carrying two persons #cf #e4 ,sub-station at ,mount ,wilson ,observatory #cg #f4 ,type of airplane used in #aiaa on ,north ,island #ch #g4 ,discussing a flight #ci #h4 ,captain ,culver and parachute for determining wind-direction #dj #i4 ,lieutenant ,gorrell1 ,u4 ,s4 ,infantry1 as observer #da #aj4 ,point ,loma from the eastern shore of ,north ,island #db #aa4 ,san ,diego1 across ,spanish ,bight1 from ,u4 ,s4 ,aviation ,school1 at twilight #dc #ab4 ,instructor ,brindley and ,meteorologist ,carpenter in ,military ,tractor ,no4 #ej #dd #ac4 ,military ,tractor ,no4 #ej #de #ad4 8,trimming0 ,tractor ,no4 #ej #df #ae4 ,military ,tractor ,no4 #ej just before leaving the ground #dg #af4 ,san ,diego harbor at over two thousand feet altitude #dh #ag4 ,san ,diego viewed from an altitude of thirty-five hundred feet #di #ah4 ,military ,tractor ,no4 #ej viewed from the ground #ej #ai4 ,flying ,squad's ,wind ,direction ,pennant ,tower #ea #bj4 ,the ,aviation ,school ,motor-,boat 8,pronto0 #eb #ba4 ,u4 ,s4 ,aviation ,field at three thousand feet altitude #ec #bb4 ,repair ,shop1 ,u4 ,s4 ,aviation ,school1 ,san ,diego1 ,cal4 #ed ,the ,aviator and the ,weather ,bureau ,,chapter ,i ,,the ,,signal ,,corps ,,aviation ,,school ,,at ,,san ,,diego ,history4--,the year #aiaa marked the beginning of the ,united ,states aviation school at ,san ,diego4 ,there is no finer tribute to the equability and general excellence of the climate of southern ,california than that given in the history of aronautics4 ,it was here1 in #aijj1 that ,chanute completed his early and epoch-making observations of the flight of gulls and pelicans4 ,these contributed largely to the success of the ,wright brothers a few years afterward4 ,it was in southern ,california1 six years ago1 that ,harkness1 in an ,antoinette1 made his record monoplane flight to ,tia ,juana4 ,san ,diego witnessed the flying of the first seaplane1 by ,curtiss1 five years ago4 ,it is in this district that not only the ,war ,department aviation school and a number of commercial flying schools are located1 but also one of the large airplane,b factories in this country4 ,b ,the ,national ,advisory ,committee for ,aronautics in its report of ,october #ag1 #aiaf1 on ,nomenclature for ,aronautics1 the name airplane is substituted for 8,any form of aircraft heavier than air which has wing surfaces for sustention1 with stabilizing surfaces1 rudders for steering1 and power-plant for propulsion through the air40 ,location of the ,school4--,whatever the final action may be as to permanent location1 it has been conceded by all authorities that the situation of the aviation school on ,north ,island1 ,san ,diego ,bay1 is ideal4 7,see ,fig4 #ba47 ,the so-called island is connected with the peninsula of ,coronado by a narrow sand-spit1 and it comprises many hundred acres of level land free from buildings and any sort of overhead wires4 ,the island fronts the ocean on the south2 ,point ,loma on the west with the narrow entrance to the bay between2 to the north is the city of ,san ,diego across the bay2 and ,coronado just beyond ,spanish ,bight on the east4 ,this natural arrangement gives good air conditions for beginners1 and also enables them to use the smooth waters of the bay as well as the rough ocean water for the seaplanes4 ,the proximity of this location to ,san ,diego is also a distinct advantage4 7,see ,fig4 #aa47 ,all of the structures of the aviation school on ,north ,island are temporary1 the buildings consisting of a scattering array of huge sheds4 ,character of ,instruction4--,officers from all branches of the army volunteer for this service4 ,the qualifications of an aviator are caution1 judgment1 and technical skill4 ,deficiencies in caution and judgment being temperamental are rarely remedied1 while technical skill is largely a matter of acquirement4 ,less than ninety days are allowed for qualification as a junior aviator1 and if in that period the officer's deficiencies are found to be inherent1 he returns to his company4 ,the school is a place for hard work and quick thinking4 ,detail in the repair shop is part of the course1 as is also the use of the gasoline engine in motor trucks as well as in aircraft4 7,see ,fig4 #bb47 ,theory and practice are closely united3 the former is carried on by means of bi-daily lectures1 while the early morning hours are devoted to flying4 ,pilot-and-observer machines equipped with double control are used in instruction4 ,the aviation instructor ascends with the student and allows him to manipulate the controls1 only resuming the management of the airplane in an emergency4 ,needless to say1 the life of an instructor is a most hazardous one and full of thrills4 ,his duty is to be on the alert to correct errors in the manipulation of the machine4 ,after every trip the instructor reviews1 point by point1 the features of the flight1 showing the pupil his deficiencies and explaining how he may avoid them in the future4 ,the instruction is terse but kindly1 and the manner of imparting this information leaves nothing to the imagination4 ,after watching student and instructor1 and closely studying the finished work of an aviator1 it is my opinion that in no other occupation must there be such perfect cordination between mind and muscle3 the perfectly qualified aviator is the modern super-man4,c ,c ,the army aviator of today is picked for his quickness of mind and body1 and the first thing that strikes you about him is a sort of feline1 wound-up-spring alertness4 ,then you note his reticence1 the cool reserve of a man whose lot is to express himself in deeds rather than words4 ,and1 lastly1 there is the quiet seriousness1 verging almost on sadness1 of a man who must hold himself ready to look death between the eyes at any moment and yet keep his mind detached for other things4--,lewis ,r4 ,freeman in the ,atlantic ,monthly4 ,results of a ,year's ,work4--,during the year #aiae1 the students of the aviation school made #c1feb flights with a total time aloft of #a1eaf hours1 and a mileage of #ie1jjj4 ,as regards weather conditions affecting flights1 it will be found interesting to note ,chart ,no4 #e giving number of flights and duration for the fourteen months ending ,august1 #aiaf1 which shows that work progressed regardless of weather1 and at an increasing rate4,d ,in ,february1 a military tractor-seaplane 7an all-,california product71 #abe-;horsepower motor1 with twenty-six gallons of gasoline1 four gallons of oil1 and three passengers1 making a total weight of #c1ajj pounds1 reached an altitude of #ab1cfb feet4 ,this was the world's record1 the previous altitude under the same conditions having been #i1jjj feet4 ,d 8,it is estimated that the average cost to ,france of training each pilot is five thousand dollars 444 no less than from four to six months are devoted to the training of finished pilots4 ,although ,i have just come from ,france1 the progress of aviation is so rapid that much of my own knowledge may be out of date before ,i again return to the front40--,c4 ,d4 ,winslow1 8,with the ,french ,flying ,corps10 #aiag1 #d-e3 ,n4 ,y4 ,,chapter ,,ii ,,applied ,,meteorology ,,for ,,the ,,aviator ,activities of the ,weather ,bureau in ,relation to ,aronautics4--,naturally the progress of arial navigation has at all times been rather closely connected with the ,weather ,bureau4 ,for over a decade the ,bureau has not been content with surface observations but has maintained laboratories for the study of the upper air4 ,the results of its observations are considered a mine of information for the student aviator4 ,prof4 ,charles ,f4 ,marvin1 the ,chief of the ,weather ,bureau1 is a member of the ,national ,advisory ,committee for ,aronautics1 and chairman of a subcommittee engaged on the determination of the problems of the atmosphere in relation to aronautics4,e ,e ,monthly ,weather ,review1 #aiae1 #cb3ejj4 ,washington4 ,the first official coperation between the ,weather ,bureau and the ,war ,department aviation school was inaugurated in the year #aiad by ,dr4 ,w4 ,j4 ,humphreys1 ,professor of ,meteorological ,physics1 when he was detailed to give a course of lectures4 ,it was during this course that he lectured on 8,holes in the ,air40,f ,this paper has been reprinted as a textbook for the aviation school4 ,f ,popular ,science ,monthly1 #aiad1 #dd3ah-cd1 ,n4 ,y4 ,early ,studies in ,aronautics4--,unofficially1 however1 the coperation extended back some fifteen years prior to that time1 when the writer was in charge of the local office of the ,weather ,bureau at ,san ,diego1 and assisted the aronautical engineer1 ,octave ,chanute1 in his observations and experiments on ,san ,diego ,bay4,g ,at this time hundreds of photographs of sea-gulls1 pelicans1 and other soaring birds were made1 and both birds and photographs studied and analyzed4 ,ever since then more or less interest has been taken by the writer in arial navigation4 ,during an assignment to the ,central ,office the work of the ,wright brothers was observed and studied4 ,the association with the late ,octave ,chanute and his friends1 the ,wrights1 during their experimental flights at ,fort ,meyer1 ,virginia1 in ,september1 #aijh1 is counted among the many pleasant memories of the ,washington visit4 ,it was here that was witnessed the first flight with a passenger 7see ,fig4 #d71 ,mr4 ,orville ,wright taking up with him ,major 7now ,colonel7 ,george ,o4 ,squier1 the present head of the aviation branch of the army4 ,such was the infancy of the flying-machine that at that date no fatalities had occurred4 ,a few years later the writer had the pleasure of accompanying ,mr4 ,glenn ,curtiss while he was determining a site for his school1 which was finally located on ,north ,island4 7,see ,fig4 #f47 ,shortly afterward1 from this place1 ,harry ,harkness made record amateur cross-country flights in an ,antoinette monoplane4 ,g 8,climate and ,weather of ,san ,diego10 ,carpenter1 #aiac1 #eg-ei1 ,san ,diego4 ,active ,work of the ,weather ,bureau4--,during the score of years that the writer has been in charge of the ,san ,diego and ,los ,angeles stations of the ,weather ,bureau1 interest in flying has been cumulative4 ,efforts have been made to furnish aviators with available data so that at the present time a day seldom passes without conference ,with officials or students of ,government or private flying schools in this vicinity4 ,lectures on ,meteorology as ,applied to ,aviation4--,through the ,war ,department1 ,october1 #aiae1 on request of the commanding officer of the ,signal ,corps aviation school1 at ,san ,diego1 the writer was directed by the ,chief of the ,weather ,bureau to deliver two lectures of which the following are outlines3 8,what the ,weather ,bureau ,offers the ,aviator0 7,illustrated by #cg lantern-slides from photographs by the author7 ,introductory3 ,weather service once part of the ,signal ,corps1 ,u4,s4,a4 ,transfer in #ahia to the ,department of ,agriculture4 ,distribution of weather stations in the ,united ,states3 ,character of data obtainable3 ,advance data from the daily map such as ,position of high and low areas4 ,weather conditions from sub-stations in vicinity4 ,the weather map3 ,how constructed4 ,how distributed4 ,specimen maps showing differing conditions in ,california4 ,winds1 velocity and frequency3 ,on-shore4 ,off-shore4 ,discussion of air conditions ,december #bj-bb1 #aiad4 ,the international weather map4 ,relation to weekly forecasts4 ,cardinal climatic features3 ,ascending winds and types producing them3 ,cloud1 fog1 precipitation4 ,descending winds3 8,northers0 and dust-storms4 ,thermograph and hygrograph traces4 ,factors in the meteorology of southern ,california3 ,influence of latitude3 ,sea4 ,mountains4 ,desert4 ,path and distribution of storm areas4 ,knowledge of local climatology necessary in flying4 ,local winds discussed3 8,woollies0 7descending wind eddies74 8,chubascos0 7south coast thunder squall74 8,santa ,anas0 7northeasterly and desiccating74 8,wilmingtons0 7northwesterly line-squall74 8,practical ,meteorology for the ,aviator0 7,illustrated by #gb lantern-slides from photographs by the author7 ,historical3 ,original work begun in ,scotland1 year #agdi4 ,characteristics-- ,english work2 ,dines' minute meteorograph4 ,french work2 ,dr4 ,berson's balloon ascent of #f miles4 ,german work2 detailed data in low altitudes4 ,american work began with ,franklin4 ,the ,upper ,air3 ,definition3 8,stratosphere0 is 7according to some authorities7 the dynamical laboratory of the atmosphere where the main causes of pressure originate4 ,results in ,america3 ,balloon meteorograph 7,fig4 #c74 ,charts showing rate of increase in wind velocity with elevation 7,chart ,no4 #d74 ,wind1 temperature1 pressure1 humidity at maximum airplane height of #bf1bdb feet4 ,stratosphere3 ,lower level in winter than in summer4 ,lower temperature in summer when surface pressure is high4 ,definition3 8,troposphere0 is the physical laboratory where cloud and rain are produced by local causes and induced by the effect of the dynamical changes in the upper air4 ,conditions within #f or #g miles of the earth's surface4 ,clouds and their ,meaning3 ,cirrus3 ,height and composition4 ,formation3 ,perpendicular shafts of clouds indicate rapid changes in weather4 ,horizontal layers1 no change and clouds will dissipate4 ,cirro-stratus1 threatening in winter4 ,cirro-cumulus1 fair and foul varieties differentiated4 ,cumulus with strong uplift4 ,alto-cumulus1 cause of parallel rows4 ,fracto-cumulus1 wind indicator1 ,point ,loma 8woolly40 ,stratus4 ,alto-stratus1 favorable for flying4 ,strato-cumulus1 long shallow rolls1 threatening in winter4 ,cumulo-nimbus1 unsafe air conditions for flying4 ,fracto-nimbus1 waterspouts and their causes4 ,velo cloud1 examples1 cause1 effect1 distribution1 density4 ,fog1 examples of great fog-belts4 ,,chapter ,,iii ,,narrative ,,of ,,weather ,,observations ,,from ,,an ,,airplane ,in order to qualify as meteorologist competent to confer with aviators1 it seemed desirable to become personally acquainted with some of the conditions that confronted them4 ,as a matter of professional acquirement therefore1 ,i was glad to accept an invitation to go aloft after the necessary official arrangements had been made with ,washington4 ,this trip was in line with the previous endeavors of applying practical meteorology to the science of flight and appropriately extended the work which was begun in ,san ,diego with ,chanute and the sea-gulls fifteen years before4 ,object of ,flight4--,i wished to put myself in the student's place and learn at first hand the practical facts he demanded from weather observations and to acquaint myself with everything possible that might be of value to an aviator4 ,there were two definite things of which ,i desired knowledge3 first1 to determine the height of the upward trend of the sea-breeze over ,point ,loma which causes the mysterious 8woolly0 of a score of years' acquaintance from a yachting standpoint2 second1 to observe the extent1 form1 and composition of the velo cloud which is the characteristic sun-cover of ,california4 ,preparations for the ,ascent4--,aviator ,instructor ,oscar ,brindley 7the #aiae winner of the ,curtiss trophy71 in military tractor ,no4 #ej1 was assigned as pilot4 ,it may be stated here that the accepted definition of aviator is a pilot of a flying-machine heavier than air4 ,the airplane used in my first flight 7see ,fig4 #ac7 was made in ,los ,angeles and is the present standard army model4 ,this tractor has an #hj-;horsepower engine and #h-;foot propeller4 ,it is #ba feet long1 has a wing-spread of #ch feet1 supporting area #cfd square feet1 and a flying radius1 with two persons1 of #cjj miles4 ,the maximum altitude attained with this model at ,san ,diego was #ac1jjj feet4 ,before being placed in service the machines are thoroughly gone over at the repair shop 7see ,fig4 #bb71 and the motors are run at full speed for twenty-four hours1 after which they are taken down and subjected to scrutiny for possible defects4 ,all of the struts1 guys1 and wires are closely examined2 the boltheads are all drilled1 wired1 and soldered so that no amount of vibration will loosen them4 ,regardless of the length of the flight1 each machine1 before going up again1 is given a rigid inspection and not until the mechanicians have tested every part is it pronounced ready4 ,not being prepared with a regulation aviation suit1 ,i was loaned a leather jacket by one officer1 face-goggles and safety helmet by others4 ,i then took my place in the observer's seat forward and was strapped into it with the safety belt 7see ,fig4 #ab74 ,i was cautioned to let my body give way as the waist-controls were moved from side to side and not pay any attention to the steering rudder wheel which had a way of mysteriously revolving1 advancing and receding4 ,in cranking an airplane1 a certain formula is always gone through4 ,the mechanician at the propeller calls out1 8,close60 ,the aviator closes the switch and repeats the word4 ,this short-circuits the ignition apparatus so that no spark occurs in the cylinders4 ,the propeller is turned in order to introduce explosive mixtures into the cylinders4 ,when ready to start the mechanician says 8,open60 ,the aviator opens the switch and repeats the word4 ,the charges in the cylinders then fire when the propeller is turned4 ,after the engine starts1 the machine is 8trimmed0 by helpers and jockeyed for a favorable 8take-off0 into the air4 7,see ,figs4 #ad1 #ae47 ,this model of airplane climbs on a gradient #a to #g2 its minimum speed is #da miles per hour4 ,in other words1 if the speed is less than #da miles per hour the machine will not fly horizontally4 ,the ,ascent4--,the tractor was headed into a #cj-mile northwesterly wind so that the 8take-off0 was quick and easy2 there were only a few seconds spent rolling over the field1 when the airplane left the ground and ,i felt the never to be forgotten cushioning feeling of the air4 ,for ten seconds there was experienced a decidedly weakening nervous chill1 which occurred to me once before when making a high dive from a spring-board4 ,it was the sort of physiological disturbance that can only be counteracted by immediately pulling one's self together saying1 8,well1 here goes nothing60 ,the momentary depression was immediately followed by a corresponding elation of feeling which strange to say did not leave me during the trip and is always associated with thoughts of the journey4 ,there was no dizziness1 although ,i am peculiarly susceptible to the least change in balance4 ,the earth did not recede as we progressed steadily upward2 we seemed part of the earth1 but not of it4 ,although the airplane reached an altitude of #c1jjj feet in a comparatively few minutes1 the barometer falling from #cj4j to #bg4j inches1 the decreased bodily pressure was not at all noticeable4,h ,h ,trans-,american ,climatic ,association1 #aiae1 #ca3bj1 ,hot ,springs1 ,va4 ,next to the supporting quality of the atmosphere ,i had noticed the #gj-mile blast of air as the airplane pushed its way steadily onward and upward4 ,naturally1 the exhaust of the motor in addition to the roar of the wind made conversation impossible4 ,some airplanes have telephone communication between observer and pilot4 7,see ,fig4 #i47 ,during one flight in a machine not so equipped1 the passenger noticed the breaking of some apparatus4 ,knowing that it was impossible to make himself heard he hastily scribbled the word 8,accident60 on a bit of card1 whereupon the pilot shut off his engine and glided to earth4 ,two-thousand ,feet above ,point ,loma4--,carrying out my suggestion as to investigating the 8woolly10 the pilot drove the machine straight for ,point ,loma and those unseen arial breakers4 ,suddenly there were two distinct 8wallops0 and ,i felt the fuselage beneath me respond as if struck by a stuffed club4 ,there was evidently first a surge then a drop1 and it was the descending current of air that deprived the airplane of the supporting medium1 hence the shock4 ,point ,loma itself1 from this altitude1 and seen directly from above1 looked very like a barracuda's backbone--long1 low1 and ugly4 ,although this peninsula 7see ,fig4 #ba7 is less than #ejj feet high it so effectively deflects the prevailing northwesterly wind that the upward surge has been noticed by aviators at an altitude of #d1jjj feet4 ,it is no wonder then that these descending winds1 called 8woollies0 7from their churning the water into isolated masses which look like tufts of wool71 are dreaded alike by yachtsmen and birdmen4 ,they have been known to carry away topsails from too closely venturing schooners and student aviators always give the vicinity of ,point ,loma a wide berth4 ,no ,winds ,aloft4--,we had not changed our direction since leaving the ground1 but after passing over ,point ,loma the airplane was put sharply on a port course4 ,i had been expecting this and must confess1 somewhat dreaded it1 innocently thinking that a #cj-mile wind added to our #gj-mile rate of speed would 8heel0 the craft to an uncomfortable angle when the course was changed from northwesterly to southerly4 ,what was my astonishment to find that the putting about was unaccompanied by any of the nautical motions such as tilting or canting4 ,theoretically one may be ever so well grounded in physical laws but it seems to take actual experience to bring their truth home to us4 ,of course there can be no wind in the air2 when we entered the air it was moving #cj miles an hour in relation to the earth but as soon as we were free from the earth the velocity of the wind had no effect on our flight4 ,no matter how strong the gale1 so far as it concerned the airplane1 if the wind be steady no difficulty is experienced2 the aviator is concerned only by wind-shifts4 ,the ,velo ,cloud ,seen from ,above4--,in kindergarten days ,i remember that one of the first questions ,i asked was 8,are clouds smoke80 ,and this early query was really first answered in the air4 ,fog on a mountain top may be cloud1 but somehow cloud free from close proximity to the earth seems different4 ,the machine was put through the cloud blanket much as a horse takes a hurdle2 it seemed unlike fog and more of a palpable substance4 ,as we emerged1 the sun was shining on it like a silvery sea with gently undulating surfaces and it looked for all the world as supportable as layers of cotton-wool4 ,many times have cloud-banks from mountain tops been observed1 yet the upper side of the velo cloud from a flying-machine looked very different4 ,the cloud was only four or five hundred feet thick and extended inland a few miles in irregular outline4 ,the seaward edges of the velo cloud were not ragged1 and apparently paralleled the coast for #aj or #ae miles4 ,such was the exhilaration and confidence the air gave that ,i can understand how parachute jumpers confidently step off into space1 for to them the air is a supporting medium no more terrible than a transparent sea to a good swimmer4 ,i believe that the record parachute drop was made in #aiaf by ,colonel ,maitland1 of the ,english ,royal ,flying ,corps1 who descended in a parachute #aj1jjj feet from an airplane4 ,fifteen minutes was occupied in the descent4 ,ease of ,vision at #c1ejj ,feet ,altitude4--,at this altitude the ease of vision is most remarkable4 ,at this height1 with perpendicular vision1 the eye is possessed of wonderful powers4 ,in those 8solitudes august with stars0 men not only 8mount up with wings as eagles0 but are given the eagle's unobstructed vision4 ,birds have been credited with much too keen vision4 ,from this height of several thousand feet every object stood out with remarkable distinctness4 ,automobiles racing along the ,el ,cajon boulevard to ,lakeside were readily picked up with the unaided eye although #bj miles away4 ,looking down over the aviation field the long compass mark and the wind-direction pennant 7,figs4 #ai and #bj7 were easily distinguished4 ,the bay and ocean1 however1 gave the most remarkable revelation1 for the bottom of the bay and the shallow ocean shore were plainly discernible4 ,the absence of water as well as air refraction explains why submarines cannot hide from an airplane3 one of the army aviators told me that a submarine cannot ordinarily sink so low that it cannot be seen from an airplane4 ,color of ,landing-ground ,important4--,owing to the absorption and reflection of sunlight1 there is a distinct variation in the character of otherwise similar landing-ground4 ,a field1 dark from recent plowing 7or burning71 will heat the air over it faster than will a field of stubble1 hence over the former field there will be the greater air disturbance1 and this will affect the ease of landing4 ,air is heated by contact and convection4 ,one of the aviators said that recently he was descending1 and had all but reached the ground when a localized convectional current hurled his machine upward some distance but immediately afterward deposited him on the ground without damage4 ,spiraling ,down #c1jjj ,feet4--,speeding ever in wide circles the course lay southeast over the upper part of ,san ,diego ,bay4 ,the city of ,san ,diego presented the usual checkerboard appearance 7,fig4 #af71 and even at this altitude it would seem easy to drop an orange at almost any point4 ,the velo cloud was lifting and we could see the gradual disappearance as it melted rather than drifted from ,north ,island4 7,see ,fig4 #ag47 ,the gliding descent was made from an altitude of #b1ejj feet1 starting above ,san ,diego4 ,as the aviation school was approached1 we could see a number of machines in the air1 three below and two above us1 circling about like hawks4 ,and1 like soaring birds1 these machines had their air-lanes1 designated courses and levels being devoted to the different classes of machines4 ,the landing was made without incident and the hour's flight was ended4 ,outline of ,meteorological ,work at the ,aviation ,school4--,at the close of the lecture detail1 the attention of the student aviators was called to the importance of their having as thorough knowledge as possible of the fundamentals of meteorology4 ,the application of these fundamentals to the analysis of air conditions met with in their daily flights was shown to be essential4 ,investigations as to varying wind direction were taken up by one of the staff instructors by the use of small parachutes to be dropped at different altitudes4 7,see ,fig4 #h47 ,through the coperation of the local official in charge of the ,san ,diego ,weather ,bureau station1 duplicate signal sheets were available from which the student officers made their local weather maps4 ,from these maps and their own flights1 they could arrive at some relationship between the actual and the theoretical #c1jjj- and #aj1jjj-;foot level maps prepared from the ,bigelow formula1 as used by the ,bureau4 ,lectures were given on temperature and its distribution2 winds1 moisture1 and clouds were also made part of the course1 one of the papers of the ,bureau,i being reprinted by the aviation school by permission of the ,chief of the ,bureau and used as a textbook4 ,the ,weather ,bureau furnished the station with a standard set of meteorological instruments so that the student officers could become perfectly familiar with the regular equipment at the ,weather ,bureau stations4 ,i 8,clouds of ,california10 ,carpenter1 #aiad1 #bd1 #b;d ed41 ,ft4 ,leavenworth 7,u4 ,s4 ,army ,press74 ,extending the ,usefulness of the ,bureau to the ,aviators4--,practical utilization by the aviators of this district of the information possessed by the ,bureau has received considerable impetus during the past six months4 ,during the cross-country flights of ,april and ,may1 #aiaf1 the ,los ,angeles station was directed by the ,chief of ,bureau to furnish weather and flight conditions between ,san ,diego and ,los ,angeles4 ,with the aid of the general weather-map data from the regular stations1 and special observations of wind1 weather1 and fog conditions on the immediate coast near ,los ,angeles1 and on ,mount ,wilson1 it was possible to issue satisfactory forecasts of flying conditions4 ,the eye-observations of fog-heights as determined by the ,weather ,bureau coperative station at the ,mount ,wilson ,solar ,observatory were especially valuable4 ,from this mountain 7#f1jjj feet elevation7 it is possible on a good day to see the whole length of the coast from ,point ,firmin1 ,san ,pedro harbor to ,point ,loma1 ,san ,diego ,bay4 ,knowing different levels1 the observer at ,mount ,wilson was able to give actual thickness and extent of the fog-belt and its past twenty-four-hour history4 ,,chapter ,,iv ,,investigating ,,the ,,upper ,,air ,balloon ,soundings into the ,stratosphere4--,it was the writer's privilege to be present when some highly interesting and instructive experiments made by the ,weather ,bureau in coperation with the ,smithsonian ,institution1 in sounding the upper air were made at ,avalon1 ,santa ,catalina ,island1 off the coast of southern ,california in ,july and ,august1 #aiac4;,j ,the results of this work were in close agreement with similar soundings of the upper air throughout other surveyed portions of the earth's atmosphere1 and a record ascension for this country was made on ,july #cj--cb1fdc meters or #bj miles4 ,in common with other observations of temperatures in the stratosphere1 the minimum temperature of these soundings 7-#ij ,f41 ,august #c7 was registered within the first #aj miles4,k ,j ,university of ,california ,chronicle1 #aiae1 #ag3a-be1 ,berkeley4 ,k ,monthly ,weather ,review1 #aiad1 #db3daj1 ,washington4 ,of especial interest to the aviator is the table on the next page which shows wind velocities increasing with elevation as determined by observations of the ,avalon balloons4 ,,record ,,of ,,avalon ,,ascents1 ,,july-,,august1 #aiac ,table showing ,theodolite observations of wind velocities 7meters per second7 at elevations of #a1jjj and #e1jjj meters ,meters ,meters ,meters ,meters ,meters ,meters,meters,meters per per per per per per per per ,meterssecond second second second second secondsecondsecond,mean #e p4m4 #e p4m4 #aj a4m4#aj a4m4#aj a4m4#e p4m4#d p4m4#e p4m4 ,july #bd;,july #bg;,july #ca;,aug4 #a ,aug4 #b ,aug4 #c;,aug4 #g;,aug4 #h ---------------------------------------- ----------------------- #a1jjj #b4e #a4j #e4f #f4f #b4c #e4h #g4a #a4i #d4a #a1ejj #f4b #j4h #f4b #h4a #c4c #e4j #f4d #a4e #d4g #b1jjj #h4j #a4b #e4h #g4j #d4a #d4e #f4e #f4j #e4d #b1ejj #aj4j #a4h #aj4h #e4g #e4b #d4b #d4g #c4f #e4h #c1jjj #ab4j #b4c #i4d #f4a #g4b #e4b #c4e #d4a #f4b #c1ejj #ab4h #b4e #h4j #f4g #g4d #f4a #d4f #d4f #f4f #d1jjj #ac4f #c4h #aa4b #g4d #i4b #e4b #f4d #c4b #g4e #d1ejj #ad4c #e4b #ad4f #h4e #aa4b #a4h #g4h #c4j #h4c #e1jjj #ba4b #f4b #ab4h #aj4c #aj4d #b4c #c4d #i4e ---------------------------------------- ----------------------- ,charts ,showing ,upper-air ,weather ,conditions4--,it is believed that the following charts when examined in connection with the accompanying explanation in the text will give the reader something of an outline as to the conditions existing in the upper regions of the atmosphere4 ,illustration3 ,,chart ,,no4 #a ,horizontal ,projections of the ,paths of the ,sounding ,balloons ,liberated at ,avalon1 ,california1 ,july #bc to ,august #aj1 #aiac ,reproduced from the ,monthly ,weather ,review1 #db3 #dbc ,this figure shows the horizontal projections as far as the balloon was observed1 not the entire distance traveled until it landed4 ,illustration3 ,,chart ,,no4 #b ,vertical ,temperature ,gradient1 ,avalon1 ,california1 ,july #bg1 #aiac ,solid line represents the ascent of the recording apparatus1 the dotted line the descent4 7,verticals #be ,c4 or #de ,f47 ,reproduced from the ,monthly ,weather ,review1 #db3 #dab ,illustration3 ,,chart ,,no4 #c ,mean ,vertical ,temperature ,gradient ,figure reproduced from ,monthly ,weather ,review1 #db3 #dac4 ,altitude values are in kilometers at the left1 and in miles at the right3 ,temperature values are in ,centigrade at bottom1 in ,fahrenheit at top4 ,maximum airplane altitude #bf1bdb feet or #e miles4 ,illustration3 ,,chart ,,no4 #d ,diagram ,showing ,increase of ,wind with ,elevation ,data from ,eight ,meteorographs ,from the article 8,free ,air ,data in ,southern ,california1 ,july and ,august1 #aiac0 by ,dr4 ,wm4 ,r4 ,blair1 ,professor of ,meteorology1 in the ,monthly ,weather ,review1 for ,july1 #aiad1 it is learned that the wind shifts from west to east rather abruptly at #af to #bj km4 7#aj to #ab miles72 below this level down to about #e km4 7#c miles7 it is quite uniformly from the west4 ,extremes3 ,maximum wind velocity #ba4b miles1 #e1jjj meters elevation1 #e ,p4,m41 ,july #bd2 minimum wind velocity #j4h miles1 #a1ejj meters elevation1 #e ,p4,m41 ,july #bg4 ,the table shows a steady increase in velocity of the wind with elevation1 the data being obtained from the eight meteorographs4 ,there were four morning flights 7,july #ca1 ,august #c1 #g1 #h7 and five afternoon flights 7,july #bd1 #bg1 ,august #c1 #g1 #h1 #aiac71 and elevations were computed for nine heights1 #a1jjj to #e1jjj meters4 ,beyond the #e1jjj meters the records show that from #b to #g miles altitude the wind increases at approximately the same rate that the density of the air decreases4 ,illustration3 ,,chart ,,no4 #e ,chart ,showing ,number of ,flights and ,duration in ,hours for the ,months of ,july to ,december1 #aiae1 and ,january to ,august1 #aiaf ,prepared by the ,war ,department1 ,signal ,corps ,aviation ,school1 ,san ,diego1 ,california1 and furnished through the courtesy of ,col4 ,w4 ,a4 ,glassford1 ,signal ,corps1 ,u4 ,s4 ,army1 ,commanding ,officer1 ,september #ad1 #aiaf4 ,illustration3 ,,fig4 #a4 ,,congressional ,,medal ,,awarded ,,wright ,,brothers 7,designed by ,morgan7 ,this medal was awarded ,orville and ,wilbur ,wright by resolution of ,congress1 ,march #d1 #aiji4 ,bronze replica in possession of the writer4 ,photographed ,may #ca1 #aiaf1 by permission of the ,director of the ,mint1 ,philadelphia ,illustration3 ,,fig4 #b4 ,,ascent ,,of ,,sounding-,,balloons ,,at ,,avalon ,photographed ,july #bg1 #aiac ,this set was liberated from the base of the ,u4 ,s4 ,weather ,bureau1 ,avalon1 ,catalina ,island1 ,california1 at #d4eg ,p4,m41 ,july #bg1 #aiac1 and rose to a height of #bc1hgj meters in one hour and three quarters when one of the balloons burst and the descent began4 ,this was observed by ,carpenter at the theodolite4 ,illustration3 ,,fig4 #c4 ,,metrograph ,,which ,,made ,,the ,,ascent ,,of ,,july #bg1 #aiac ,photographed ,august1 #aiac ,this meteorograph rose to a height of #bc1hgj meters 7#id1gaf feet71 at which height the pressure was #bc mm4 7#j4ijf inches71 temperature -#eb4a ,c 7-#eh ,f471 relative humidity #ba per cent1 wind ,e4 7or more precisely ,s4 #gi degrees ,e471 velocity #f4a m4p4s4 7#ad miles per hour71 but the minimum temperature was registered at #ae1bbh meters 7#di1ifj feet7 when the thermometer showed -#fd4g ,c4 7-#he ,f471 at which time the pressure was #hi mm4 7#c4ejd inches of the barometer71 relative humidity #ai per cent1 wind ,n4,w41 #c4d m4p4s4 7#h miles per hour74 ,the basket was picked up at sea off ,oceanside1 ,san ,diego ,county1 about #ij km4 7#ade miles7 east of ,avalon4 ,for the first #f miles of ascension the balloon moved upward at the rate of #h miles per hour4 ,illustration3 ,,fig4 #d4 ,,first ,,flight ,,of ,,airplane ,,carrying ,,two ,,persons ,photographed ,september #aj1 #aijh ,this photograph was made at ,fort ,meyer1 ,virginia1 of the original ,wright biplane1 piloted by ,mr4 ,orville ,wright ,with ,colonel ,g4 ,o4 ,squier1 ,u4 ,s4 ,a41 as first passenger4 ,when this photograph was made no fatalities in airplane flight had occurred2 the first victim1 ,lieutenant ,selfridge1 ,u4 ,s4 ,a41 was killed while riding with ,mr4 ,wright in the same biplane shown above1 on the ,tuesday following the ,saturday this photograph was made1 the machine falling to the ground at a spot which is practically the center of the picture1 but near the trees which are part of ,arlington ,national ,cemetery4 ,illustration3 ,,fig4 #e4 ,,mount ,,wilson ,,observatory ,photographed ,december #bd1 #aiae ,a special meteorological station of the ,weather ,bureau was established on ,mount ,wilson1 ,december #be1 #aiae1 and on ,april #a1 #aiaf1 daily reports of temperature1 weather1 precipitation1 relative humidity1 fog and other conditions were first telegraphed to the local office of the ,weather ,bureau at ,los ,angeles for publication and distribution4 ,the photograph shows the location of the meteorological observatory7997 and the valleys below4 ,from the elevation of the observatory 7#f1jjj feet above sea-level71 it is possible for the observer to determine the thickness and extent of fog as it is feasible to see as far southwesterly as ,point ,loma on a clear day1 and southerly to ,santa ,catalina ,island4 ,such observations and reports have been made and forwarded without interruption to date4 ,they have proven of incalculable value to the aviators making cross-country flights4 ,the station on ,mount ,wilson is maintained through the coperation of the ,carnegie ,institute of ,washington4 ,illustration3 ,,fig4 #f4 ,,type ,,of ,,airplane ,,used ,,in #aiaa ,,on ,,north ,,island ,photographed ,october1 #aiaa ,this photograph of ,mr4 ,glenn ,curtiss in his 8pusher0 airplane was made shortly after the ,curtiss ,school of ,flying was established in #aiaa1 on ,north ,island4 ,at his right is ,local ,forecaster ,carpenter4 ,comparison of this machine1 which four years ago was the last word in airplanes1 with the tractor shown on the opposite page1 indicates the rapid progress in design4 ,illustration3 ,,fig4 #g4 ,,discussing ,a ,,flight ,photographed ,october #ah1 #aiae ,aviation ,instructor ,oscar ,brindley discussing a flight with ,captain ,clarke1 ,u4 ,s4 ,a41 and other officers at the ,u4 ,s4 ,aviation ,school at ,san ,diego4 ,mr4 ,brindley is standing by the side of ,captain ,clarke in the group at the right4 ,after every flight the ,instructor reviews1 point by point1 the features of the flight1 showing the pupil his deficiencies and explaining how he may avoid them in the future4 ,the officer at the left1 ,lieutenant ,brown1 has the regulation leather leggings1 coat and helmet1 and is ready to go up as soon as the mechanicians 7who may be seen at the extreme left7 finish inspection and pronounce the airplane fit for the next flight4 ,illustration3 ,,fig4 #h4 ,,captain ,,culver ,,and ,,parachute ,photographed ,october #ba1 #aiae ,captain ,c4 ,c4 ,culver1 ,u4 ,s4 ,cavalry1 ,adjutant1 ,aviation ,school1 with a parachute in his hand1 having word with ,captain ,l4 ,w4 ,patterson1 ,u4 ,s4 ,a41 before the latter's flight4 ,the object of the parachute is to determine changing wind-direction at different heights4 ,the airplane wireless record is now held by ,captain ,culver4 ,in ,october1 #aiaf1 he sent a message #aai miles from ,santa ,monica to ,san ,diego1 ,california1 while flying at an altitude of #a miles4 ,he received a radio message from a distance of #aa miles while flying #g1jjj feet aloft4 ,he is also the first military aviator to rig up two airplanes so that they could exchange messages while in flight4 ,the radio set used weighed less than forty-five pounds4 ,illustration3 ,,fig4 #i4 ,,lieutenant ,,gorrell1 ,u4 ,s4 ,,infantry1 ,,as ,,observer ,photographed ,october1 #aiae ,the noise of the motor1 together with the terrific blast of air1 makes conversation impossible between the pilot and observer2 for that reason telephones are sometimes installed as noted in this photograph4 ,lieut4 ,edgar ,s4 ,gorrell is shown as the observer in this photograph4 ,he has since qualified as an aviator and made a brilliant record in the ,mexican activities in #aiaf4 ,illustration3 ,,fig4 #aj4 ,,point ,,loma ,,from ,,the ,,eastern ,,shore ,,of ,,north ,,island ,photographed ,october1 #aiae ,the peninsula of ,point ,loma rises to an elevation approximating #ejj feet1 and as it lies approximately north and south1 it interposes a considerable barrier to the prevailing westerly winds4 ,the eastern side of ,point ,loma is very precipitous4 ,these factors tend to produce winds called 8woollies0 which are a distinct menace to all small boats and air-craft1 unless the air-craft have an elevation exceeding #c1jjj feet on a normal windy day4 ,illustration3 ,,fig4 #aa4 ,,san ,,diego1 ,,across ,,spanish ,,bight1 ,,as ,,seen ,,from ,,the ,u4 ,s4 ,,aviation ,,school ,,at ,,twilight ,photographed ,october1 #aiae ,contrasted with the photograph of ,point ,loma on the opposite page1 this picture shows the ideal water conditions for trying out seaplanes4 ,shortly before this picture was taken1 one of the pilots of the ,curtiss ,aviation ,school1 also on ,north ,island drove a big seaplane #ajj miles per hour barely skimming the surface of the water4 ,illustration3 ,,fig4 #ab4 ,,instructor ,,brindley ,,and ,,meteorologist ,,carpenter ,,in ,,military ,,tractor ,,no4 #ej ,photographed ,october #bj1 #aiae ,instructor ,oscar ,brindley and the observer1 ,meteorologist ,ford ,a4 ,carpenter1 ,u4 ,s4 ,weather ,bureau1 leaving the ground for a flight4 ,in the military tractor used generally by the ,army1 the observer sits forward while the pilot occupies the after cockpit4 ,this machine1 like all others used in the military service1 has dual control4 ,illustration3 ,,fig4 #ac4 ,,military ,,tractor ,,no4 #ej4 ,,type ,,of ,,biplane ,,used ,,in ,u4 ,s4 ,,army ,,service ,,made ,,by ,,glenn ,,martin1 ,,los ,,angeles1 ,,cal4 ,photographed ,october1 #aiae ,motor1 horsepower1 #hj3 revolutions per minute1 #a1bgg4 ,diameter of propeller1 #h feet4 ,load of #ci gallons gasoline1 #b gallons oil4 ,flying radius with normal equipment1 two persons1 #cjj miles4 ,maximum altitude obtained with this model at ,san ,diego1 #ac1jjj feet4 ,wing-spread1 tip to tip1 upper1 #ch feet1 #aj inches2 lower1 #cd feet1 #aj inches4 ,supporting area1 upper1 #aci square feet2 lower1 #afe square feet2 total1 #cfd square feet4 ,length of fuselage from rear of propeller hub1 #ba feet1 #f inches4 ,data from ,major ,f4 ,p4 ,lahm1 ,signal ,corps1 ,u4 ,s4 ,a4 ,dated ,may #i1 #aiaf4 ,illustration3 ,,fig4 #ad4 8,,trimming0 ,a ,,tractor ,,in ,,leaving ,,the ,,ground ,photographed ,october1 #aiae ,military ,tractor ,no4 #ej just before leaving the ground4 ,in gusty weather the mechanicians steady the ends of the lower planes1 sometimes turning it by holding one edge and pushing the other4 ,in the photograph the mechanicians are giving the airplane steerageway to the right4 ,illustration3 ,,fig4 #ae4 ,,military ,,tractor ,,no4 #ej ,,just ,,leaving ,,the ,,ground ,photographed ,october1 #aiae ,before attempting to leave the ground there is always considerable jockeying for a favorable head-wind1 and the photograph shows ,instructor ,brindley maneuvering for a favorable pointing4 ,after leaving the ground1 the wind1 so long as it is not gusty1 makes no difference to the pilot4 ,illustration3 ,,fig4 #af4 ,,san ,,diego ,,harbor ,,at ,,over #b1jjj ,,feet ,,altitude ,photographed ,october1 #aiae ,the new municipal wharves are in the middle foreground and to their right may be seen the ,santa ,f station4 ,part of ,north ,island is obscured by cloud4 ,illustration3 ,,fig4 #ag4 ,,thirty-,,five ,,hundred ,,feet ,,above ,,san ,,diego ,photographed ,october1 #aiae ,this photograph was made #a1jjj feet above the clouds4 ,the wharves of ,san ,diego and ,coronado may be seen in the foreground and in the middle distance4 ,illustration3 ,,fig4 #ah4 ,,military ,,tractor ,,no4 #ej ,,at #c1ejj ,,feet ,,altitude ,photographed ,october #bj1 #aiae ,the airplane1 in which the pilot1 ,oscar ,brindley and the observer1 ,meteorologist ,carpenter1 made their flight1 was photographed at the maximum elevation1 #c1ejj feet above the aviation field4 ,illustration3 ,,fig4 #ai4 ,,flying ,,squad',s ,,wind-,,direction ,,pennant ,,on ,,tower ,photographed ,october #e1 #aiae ,the regular observation tower from which all observations and notes on every flight are made is just back of the headquarters building4 ,the station anemometer is on the tower1 and the portable anemometer is to the left4 ,illustration3 ,,fig4 #bj4 ,,the ,,aviation ,,school ,,motor-,,boat 8,,pronto0 ,photographed ,october1 #aiae ,during the flying periods1 the motor-boat of the ,u4 ,s4 ,aviation ,school is kept ready for instant service in order to work in conjunction1 if needs be1 with the ,medical ,corps emergency truck on land4 ,such is the speed of this boat 7exceeding #dj miles per hour7 that the water no longer has resiliency1 and it is about as comfortable as riding in an old-fashioned stone-boat over rocky pastures4 ,illustration3 ,,fig4 #ba4 ,u4 ,s4 ,,aviation ,,field ,,at ,,three ,,thousand ,,feet ,,altitude ,photographed ,october1 #aiae ,part of ,coronado and the portion of land called ,north ,island1 separated by ,spanish ,bight4 ,point ,loma may be seen at the extreme upper right-hand corner of the photograph4 ,the flying-machine sheds1 buildings of the ,aviation ,school1 etc41 may be seen in the immediate foreground4 ,the ,u4 ,s4 ,cavalry camp is the white splotch in the center foreground4 ,illustration3 ,,fig4 #bb4 ,,repair ,,shop ,u4 ,s4 ,,aviation ,,school1 ,,san ,,diego1 ,,cal4 ,photographed ,october1 #aiae ,in the repair shop of the ,u4 ,s4 ,aviation ,school at ,north ,island the motors are given a gruelling test1 being run twenty-four consecutive hours at a speed greater than that given them in actual practice4 ,after this run they are taken down and each part is spread out on a large drawing-table and is subjected to close scrutiny so as to show any defect4 ,several airplanes as well as seaplanes have been reconstructed in this shop4 99 99 99 99 99 99 ,transcriber's note3 ,punctuation and spelling were made consistent when a predominant preference was found in this book2 otherwise they were not changed4 ,simple typographical errors were corrected4 ,ambiguous hyphens at the ends of lines were retained2 occurrences of inconsistent hyphenation have not been changed4