MANY years after men had reached the North and South Poles, Mount Everest - the world’s highest mountain - still defied the efforts of the most daring and determined explorers. Its icy peak, 29,141 feet above sea level, remained remote and inaccessible. Countless unknown dangers awaited those who attempted the unsealed heights of the mountain. Tragedy and disaster overcame many of the determined pioneers, some of whom did not return.
The idea of flying over the summit had attracted many pilots, but for long their ideas remained mere dreams. No engine was capable of lifting an aeroplane to such an altitude in such conditions. Such an engine might one day be evolved but, until that day arrived, Everest must remain unconquered, even by the aeroplane. The day came, however, in 1932, with the production of the first models of a new experimental engine - the Bristol Pegasus. It was not long before at least one man realized that the Pegasus was an engine that would turn dreams into reality by making possible the conquest of Everest. That man was Lieut.-Col. L. V. Stewart Blacker, home on leave from the Indian frontier.
In 1930 an American pilot had reached a height of over 40,000 feet in a Wright Apache machine with a 450 horse-power Pratt and Whitney engine. That was a single-seater aeroplane. The lightest of loads was carried and the flight was over level country with a favourable climate. It would have been too much to have asked that same engine to carry a heavy load to an altitude of
33,000 feet over mountainous country with the most unreliable of climates.
The Pegasus engine, however, was in a different class. A nine-cylinder air-cooled radial, it was supercharged and, therefore, capable of a high power output at great altitudes, and it was extremely light for the power which it developed - perhaps the most important feature of all. This quality of low weight per horse-power would be of immense value on a flight where every single detail might make the difference between success and disaster - a flight on which every ounce had to be carried to a height of six miles and kept there.
Lieut.-Col. Blacker had had some years of flying experience, and had taken his pilot’s certificate in 1911 at the Bristol Company’s school. He was joined by his friend Colonel P. T. Etherton, a born organizer and administrator. Plans were formulated, suggestions were considered from every possible angle, and slowly but surely it became certain that the attempt to fly over Everest would be carried out. The story of the great flight is largely a story of intensive research and preparation. The flight took three and a quarter hours; the preliminary work which made it possible took fourteen months. Everest was conquered in England before the aeroplanes were packed and sent to India.
The Government of Nepal was approached, as much of the flight was to take place over the least accessible part of that kingdom, and an accident of any kind would have necessitated the sending out of a relief expedition, which would have been tantamount to a penetration of Nepalese territory. The Government of Nepal granted permission, and proved friendly and helpful.
The Everest flight was even more difficult to plan, in the early stages, than several other great expeditions. So many unknown quantities were involved that months of preparation were needed to make possible the final flight of a few hours. This preparation is perhaps the greatest strain on any pioneer, and calls for self-control and patience.
The financial crisis of 1932 threatened at one time to wreck the plans of the expedition, but Lady Houston, whose generosity to British aviation was well known, supported the flight.
Air Commodore P. F. M. Fellowes, late of the R.A.F., was appointed chief executive officer, and Flight Lieutenant D. F. McIntyre was chosen as second pilot.
Abnormally Large Propellers
All this organization had been built up because of the existence of the Bristol Pegasus engine. The next, and most important task was to choose a suitable aircraft in which to install the engine. Several different types were examined, and it was finally decided to use the Westland PV 3 (renamed Houston-Westland) and the Westland Wallace. These machines might have been specially made for the task, for which they had all the necessary characteristics. They were two-seater biplanes. They had engine bearers which would take the Pegasus engines. They had high under-carriages which would permit the use of abnormally large propellers, and they had big wing surfaces for good climbing powers, large fuselages and roomy cockpits.
It was decided not to use enclosed cockpits, but to have large windscreens and to provide the observer’s cockpit in each machine with two curved doors which opened inwards. This arrangement allowed a good streamline shape to be obtained and gave a reasonable amount of comfort.
SKETCH OF THE FLIGHT ACROSS THE HIMALAYAS from Purnea, in Bihar, over Mount Everest and back. The two aeroplanes, the Westland PV 3 (renamed Houston-Westland) and the Westland Wallace, left Purnea on the morning of April 3, 1933, and flew over Nepal. Having reached the summit of Mount Everest, they circled round it and returned on a course nearly parallel to the outward course. On the next day a flight was made over the summit of Kanchenjunga (28,225 feet). On April 19 the second flight over Mount Everest was made.
Photography was to be an important part of the flight, but most of the technical difficulties were concerned with such matters as oxygen supply, heating installations and flying instruments. Everything in the aeroplanes was to be transferred fairly rapidly from a region in which the sun temperature was 180° Fahr. to one in which there might be 120 degrees of frost.
The Eagle survey cameras were mounted in suitable positions, and the cinema cameras also were conveniently installed. Special mountings had to be designed to keep the cameras steady during use. The next step - and a most important one - was the planning of the oxygen supply. The gas was carried in high-pressure steel cylinders at a pressure of 120 atmospheres. Special masks and flexible tubing were designed, but difficulties arose because of the intense cold which the equipment would have to stand. Electrically heated clothing and goggles were provided, and the electrical equipment of the aeroplanes showed signs of becoming extremely complicated. Special dynamos were installed, however, which were planned to cope with the heavy demands upon the electrical supply - heated clothing, camera motors, heated oxygen supply, and a variety of photographic apparatus. There was also the problem of telephonic communication between pilot and observer to be considered.
All these difficulties were ultimately surmounted. In an ordinary aeroplane there is little unnecessary equipment. In the Everest flight machines every single detail had to be perfect. The slightest fault in the working of one minute device might easily have been the cause of total failure of the expedition, and thus the months of patient work were vitally necessary and abundantly justified.
First View of the Peaks
Preliminary reconnaissance before the main flight was also necessary, and the possibility arose that films and plates might have to be taken to Calcutta for development. Thus it was necessary to have light aircraft available as well as the Westland machines. Three Moths - a Puss, a Fox and a Gipsy - were acquired, and these light aeroplanes were flown out to India, the big Westland machines being transported by sea. On February 16, 1933, the three Moths left Heston for Karachi, the Westlands being at that time stowed away in the liner Dalgoma.
The three machines reached Karachi safely, a fortnight after Lieut.-Col. Blacker had arrived there, having travelled in an air liner.
The chosen base for the flight was at Purnea, some 260 miles north of Calcutta and some 150 miles south of Everest. Blacker travelled to New Delhi by train and, after he had concluded his business there, went to Purnea. He inspected the sites of the canvas hangars and discussed arrangements with the Deputy Commissioner and the police, finally returning to Bhagalpur, some forty miles away.
About this time two of the Moths were being flown to Delhi. Blacker returned to Delhi, where he met Clydesdale, McIntyre and Fellowes, and the four set forth for Purnea in the two machines. It was on this journey that they received their first awe-inspiring view of the mountain they had set out to conquer. The three brilliant white peaks of Kanchenjunga, Everest and Makalu stood out majestically above a sea of haze, and, in the words of Blacker, “we could scarcely bear to glide down to land, and so to lose the beauty of this sight.”
The two Moths flew to Purnea, where the fliers found the landing ground levelled out and work in hand on the hangars. So well were all the arrangements being made that it was decided to fly back to Karachi and bring along the big Westlands. The first stop was Allahabad, and here the first misfortune overtook the expedition. A violent storm arose during the night and the Fox Moth, although firmly lashed, was blown high into the air and dashed to the ground, a total wreck. Another train journey to Delhi followed, and a generous Indian, Mr. Chawla, lent the expedition his own Puss Moth almost at a moment’s notice.
THE EVEREST MAIL being handed over to the pilot of the Westland Wallace machine before the flight over Mount Everest. Colonel P. T. Etherton, one of the organizers of the flight, is handing over the mail. Included in the mail were letters to King George V, the Prince of Wales (now the Duke of Windsor) and the late Lady Houston.
When, finally, the fliers reassembled-at Karachi, the two Westlands had been prepared for their test flights. They were taken up to 33,000 feet, and performed splendidly. The air at 33,000 feet was discovered to be 36° Fahr. warmer than it had been in England on the original test flight.
On March 22 the fliers set off for Purnea in the two Westlands and the three Moths. Much photographic practice was carried out on the journey, and the fliers landed at Purnea to find that the big canvas hangars were all ready for housing the aeroplanes.
Next came an arduous period of waiting for favourable conditions, which was also a period of rigorous training in the various tasks which each member of the expedition would have to perform on the great flight. At last, it seemed, the culmination of more than a year’s preparation was to be reached. But the wind and the weather took matters in hand; whenever the sky was clear enough for the course of a “weather balloon” to be followed up to 25,000 feet, it seemed that the wind velocities at that height were alarmingly high. Estimates showed that the highest wind in which it would be safe to make the attempt was one of thirty or perhaps forty miles an hour. Day after day the fliers waited for the wind to drop to a reasonable figure.
The weather at Purnea apparently varied in twelve-days cycles, starting with a disturbance, changing to days of clear air and little wind, but with clouds on the mountains. Then, as the cloud-caps melted away, the wind rose again. On April 3, 1933, however, one of the Moths reported the mountaintops to be clear; reports gave a wind speed of fifty-seven miles an hour. In spite of this relatively high figure, it was decided to make the attempt.
There were hundreds of tasks to be performed before the flight was begun, although everything possible had been done on the previous night. The cameras had to be prepared. Each one of the items of photographic equipment had to be cleaned every night, because of the fine, all-pervading dust that hung in the air. The oxygen supplies had to be inspected, the electrical connexions checked, all the instruments inspected, telephones tested, and so on, almost without end.
Finally, just after 8 a.m. the two big machines took off. Lord Clydesdale piloted the Houston-Westland, with Lieut.-Col. Blacker as observer. In the Westland Wallace were Flight Lieutenant McIntyre and S. R. Bonnett, the air photographer of the Gaumont-British Corporation.
By the time Blacker had performed the forty-six vital checks which he had compiled on a list, he and his companions had been in the air for some ten minutes, climbing through the haze, which generally rose to a height of some 6,000 feet. On that particular day they did not emerge from it until they reached 19,000 feet. Suddenly, however, after the machine had cleared the haze, the fliers had an amazing view of Kanchenjunga away to their right. Blacker opened the cockpit roof and looked out ahead over the Pegasus engine and there, straight in front and level with the machine, was Everest itself. To its right was the peak of Makalu, and for a long time nothing could be seen above the deep purple haze but these three incredibly brilliant white peaks.
Streaming from the crest of Everest towards Makalu was the gigantic white plume, or rafale, which shows the presence of a fierce wind blowing across the summit. By now the aircraft was flying over a region of immense glaciers - the beginning of the great mountain range - making straight for the great peak of Everest itself.
AFTER THE TEST FLIGHT, during which the aeroplanes performed splendidly. On the right is H. J. Penrose, pilot of the Westland PV 3 (renamed Houston-Westland). With him is Air Commodore P. F. M. Fellowes. They carried out a number of tests on the oxygen apparatus and other equipment at high altitudes.
Blacker was hard at work with the cameras, taking every splendid view that presented itself - taking photographs through the hatchway in the floor and at every possible angle. Suddenly the machine swooped downwards in a most alarming manner and the altimeter reading crept downwards through 2,000 feet. They were in a great downdraught, and it seemed that they would never be able to clear the crags of the South Peak, towering in front of them. But the engine was capable of the task before it, and they climbed, slowly but surely. Suddenly the machine came to the curved summit of Everest itself, seeming to clear it by a hair’s breadth. Blacker wondered momentarily whether the tail skid would strike the summit. Even at this point, so reliable was the oxygen supply to his mask that he was able to open the cockpit roof and thrust his head and shoulders out into the slipstream. He took several photographs over the top of the aeroplane, and then there began a period of perilous toil.
The pilot swung the aeroplane westward, into the huge wind sweeping downward over the crest, and it seemed for a moment that the machine could make no headway in spite of its air speed of 120 miles an hour. The aeroplane was now right in the plume of Everest, and fragments of ice rattled into the cockpit with such force that the windows were cracked.
By this time the oxygen pressure gauge showed that the supply was falling; so after a quarter of an hour in the neighbourhood of the peak the fliers headed for Purnea. The flight back was uneventful and both machines landed at Purnea at 11.25 a.m., having made the first flight over the world’s highest mountain. Among the sixty letters which had been carried over the summit (“per Everest Mail”) were three addressed respectively to King George V, the Prince of Wales (now Duke of Windsor) and Lady Houston.
Although certain minor difficulties had arisen with the vertical cameras and the heating suits, confidence in the efficiency of the equipment had been splendidly justified. To make sure of absolute perfection on the second flight, however, it was decided to fly over Kanchenjunga (28,225 feet). Some of the vertical photographs taken on the first flight had been spoiled by the dust haze; it was therefore impossible to tell whether the estimates for the exposures were correct. Thus the flight over Kanchenjunga had two main objects - the perfection of all the equipment for the next attack on Everest, and the collection of good photographs of mountain scenery in unknown country.
SPECIAL ELECTRICAL HEATING APPARATUS was provided for the Eagle cameras, to overcome the intense cold certain to be experienced over Everest. The cameras were made almost entirely of duralumin, and were covered with special jackets, each jacket being heated by electrical resistance wires sewn into the fabric. This photograph shows the cameras in position for the Everest flight.
This flight took place on April 4, and when the machines rose through the haze, at 19,000 feet, the summit of Kanchenjunga appeared to be completely clear. By the time the summit was reached, however, it was enveloped in 1,500 feet of cloud. The flight was carried out “according to schedule”, but close to the mountain and on the north-east side a sudden and prolonged disturbance was encountered by the first aeroplane. The machine rocked, twisted and shook until it seemed that it must inevitably drop into a spin; the accelerometer momentarily recorded 2·8 g. - an acceleration 2·8 times as great as that produced by the force of gravity. Having cruised in the vicinity of the mountain for some minutes, the pilot decided against attempting to cross the summit and headed south for home. This trip was somewhat more eventful than the return from Everest, and included two forced landings and an enforced wait on the second one because of petrol shortage. Communication was easily established, however, with the landing ground at Purnea, and a Puss Moth soon arrived with twenty gallons of petrol.
At many places where the fliers landed, the natives had never seen an aeroplane. At Dinajpur, the scene of the second forced landing on the return from Kanchenjunga, the arrival of a Westland was at first unnoticed, as it had kept low. Within ten minutes of landing, however, a crowd of more than 10,000 natives had assembled. Luckily, the police prevented them from doing any harm. The natives were perfectly friendly but excessively curious. They soon became used to the novelty, and the take-off was uneventful.
The Kanchenjunga flight made it possible to put all the gear into really good order for the second Everest flight, and some excellent photographs had been obtained. Only the terrible weather in the vicinity of the summit of Kanchenjunga had marred the complete success of the flight.
The first Everest flight was now proved to have been made in vain. The unexpected dust haze, rising to 19,000 feet, had prevented the taking of sufficient useful vertical photographs - one of the main purposes of the expedition. Luckily, however, every one concerned had been quite prepared for the fact that a second flight would probably be necessary, if only to add to the total area photographed.
Several cables from England urged the fliers not to take the risk of a second ascent, but they felt that the cause of British aviation might suffer if they did not make the expedition a thorough success in every detail. Nothing would deter them from their intention of making a second flight which should be free from all the minor troubles that had beset the first.
Defeating the Weather Conditions
McIntyre, the second pilot, suggested an ingenious scheme for making the best of the weather conditions. It was known that the winds at low altitudes came from the east and were not generally strong; on the other hand, the upper winds, which were powerful, came from the west. McIntyre’s plan was to fly about a hundred miles to the west or north-west of Purnea at some 3,000 feet. They would then be to the west of Everest, and could climb to 18,000 feet and fly north-east, making full use of the favourable east wind at that altitude, and turn towards the summit.
A spell of cloudy weather delayed the second flight until April 19, but on that morning conditions were favourable and the two Westlands took off from Purnea at an early hour. The wind strength at 24,000 feet was reported as eighty-eight miles an hour, and at greater altitudes it was probably even stronger. This report, however, did not prevent the fliers from starting off. Blacker was determined that nothing should interfere with the taking of really good vertical photographs this time, and for nearly an hour he was huddled over the vertical camera, helping the electric drive with the hand-operated gear and generally “feeling its pulse”. At the end of this hour Everest was straight ahead, and the camera was working perfectly. Suddenly Lord Clydesdale found the electric plug vibrating in his oxygen heater, and a few bad moments ensued while he struggled with the split pins in an effort to tighten the plug. Luckily, it was soon fixed; but a clamping screw on the survey camera began to give trouble with the cold. Various minor incidents followed in quick succession, but everything was kept successfully in action and the machine climbed on up to 31,000 feet. Blacker was busy taking oblique photographs of some of the unexplored ranges running south-west from Everest - the very aspects of the great mountain that were quite unknown.
On they flew, over the triangular crags of the South Peak, and then over the summit itself, the machine handling perfectly and everything working smoothly. Blacker was taking photographs continuously with the big survey camera, the still camera for oblique shots and a cinematograph camera. The handling of these three cameras, with the constant opening of slides, setting of shutters, covering of slides and taking of precautions against fogging, constituted a full-time task during this part of the flight.
FITTING OUT one of the Westland machines acquired for the flights over Everest. The observer’s cockpit had panels above to protect him from wind, and side windows for taking photographs. The pilot’s cockpit in front was fitted with a large windscreen, but no roof.
The flight continued until the machine was over Makalu. Superb views were obtained of the great Khumbu Glacier and of the Arun Gorge. The machine circled serenely over Everest, untroubled by the hurricane and the mighty plume sweeping away from the summit of the mountain. Eventually it was necessary to steer south on the homeward journey. All the photographic plates had been used - this time, as it afterwards appeared, with the greatest of success - and before long the aircraft landed at Purnea.
The second machine had not covered quite the same course, but had approached the South Peak from a direction slightly west of south. The vertical photographs taken from the two aeroplanes, however, gave a series of strips covering most of the unexplored country which it had been proposed to photograph, and this time the photographs were of admirable quality, free from distortion and overlapping correctly. At last it had been demonstrated that it was possible to photograph inaccessible country from the air, even at great heights.
Of all the possible sources of trouble, only two had materialized, and neither was of great importance. One was the slight deviation of the second Westland from its proposed course, because of the presence of a blanket of cloud stretching nearly to the foot of Everest; this prevented the observer from using his drift sight. The other difficulty was that the azimuth clamping screw of one of the survey camera mountings had been set too tightly and had seized up with the change of temperature. The observer was unable to rotate the camera to allow for drift. Fortunately, when the film was developed, it was discovered that the overlaps more than compensated for such small errors.
On both flights over Everest the fliers had been fortunate with their oblique photographs. On April 3 thirty-five were secured and on April 19 no fewer than fifty. Nearly all of these photographs were of good quality.
The vertical photographs taken on the second flight disclosed the existence of a curious heart-shaped patch high up on the frozen slopes of Everest. This heart-shaped patch was believed to be a hot lake. It was undoubtedly one which no man had ever seen before. The story of the flights over Everest and Kanchenjunga, hazardous though they were, reads like an account of a routine flight carried out according to a prearranged schedule. The fliers’ complete faith in all their equipment was abundantly justified by the absence of breakages and failures, and all their preliminary work and scheming, carried out in England, had at last borne fruit.
PILOT’S COCKPIT in the Houston-Westland aeroplane used in the fights over Everest in 1933. The valves and regulators for controlling the oxygen supply which enabled the pilot to breathe in the rarefied atmosphere are on the right. In the lower left-hand corner is the tail-incidence wheel, and above it the throttle and mixture control. The large dial in the centre of the panel is the revolution counter, and above it are the fore-and-aft and transverse levels. To the right are the oil temperature and pressure gauges. To the left are the altimeter and (farther left) the air speed indicator.
Everest was conquered - without loss of life. British aviation had proved itself capable of doing the impossible and every part, every small accessory, had performed the task demanded of it. The strategy of the whole expedition was above reproach and the tactics were impeccable. The greatest credit is due to organizers, fliers and all concerned. Rightly will the flight over Everest go down in history as one of aviation’s greatest triumphs.