The Future of Aerial Transport

"The force of gravity ever pulling the plane and its load to Earth will ever set a limit to the achievements of aircraft and be an insurmountable barrier to commercial success in the air"


Few subjects interest the world as does the marvel of human flight, no prospect is so alluring as 'the conquest of the air,' and when airmen, greatly daring, cross the wide seas they call forth admiration and wonder at their enterprise and courage, their skill and endurance: yet so narrow is the gulf between amazing success and tragic failure, so far are the determining factors beyond the control of the pilot, that enthusiasm yields to misgiving and even to censure, mingled with increasing skepticism regarding the value of long-distance flights.

Eight years have elapsed since Sir John Alcock, an Englishman, and Sir Arthur Whitten Brown, of American birth, crossing the Atlantic in the first nonstop flight, won the Daily Mail prize of £10,000. They started from St. John's, Newfoundland, on June 14, 1919, and landed at Clifden, Ireland, after 16 hours and 192 minutes. They had crossed the ocean at 118 miles per hour, which is still the speed record for Atlantic flights. Since that time millions have been spent on the development of the aeroplane, on the improvement of the engine, on navigational and other instruments, in order to advance and encourage the art of flying; and much also has been expended on the study of meteorology. It was therefore natural to assume that, if continuous and definite progress or startling advance in aeronautics was possible, long-distance flights could now be undertaken in more efficient machines with engines of much higher performance, with more reliable instruments of navigation, more accurate forecasts of wind and weather, with greater certainty of achievement, and less discomfort.

The £5000 New York-Paris nonstop prize offered a test of progress in aeronautics and of the practicability of long-distance ocean flights; and when the events of the past season are examined and weighed against earlier ones it will be seen that they show an advance in performance, no further 'control over the powers of Nature,' no nearer approach to commercial transport. In truth the only essential difference between the successful efforts of 1919 and the recent flights is in the load of fuel taken for the voyage. Much more petrol is now taken aboard than would then have been attempted. Special and longer runs have arranged in the direction of the prevailing or favorable winds, enormous tires and other aids are unsparingly supplied; all 'comforts' are reduced to their lowest limits to allow the last drop of fuel to be carried. Yet, in spite of these preparations, the start is more perilous. In September 1926, when Captain Rene Fonck, the ace of the French airmen, essayed the flight, disaster was immediate. The pilot took off, but the plane was overloaded, and in a few seconds it crashed to the ground in flames. The two mechanics, Clavier and Islamoff, were burned to death, and the fourteen-ton Sikorsky was utterly destroyed. In the next venture for the same prize, two more victims were claimed. On April 26, 1927, Commander Davis and Lieutenant Wooster of the United States Navy made a test flight with too heavy a load and, failing to clear a line of trees, fell into a marsh.

Lindbergh loaded up to his limit and took off with difficulty, Chamberlin carried so much fuel that the plane would not leave the ground at the first start. Byrd took as much as he dared. The hazards from dangerously full loading present themselves at the start of all long-distance flights; ambulances are placed at points where trouble is feared, and fire fighters are held in readiness for the critical moment. Yet, though a safe start be made, the load may still prove overmuch and entail misfortune or disaster. The second attempt of R.A.F. pilots to fly to India ended after one and one-half hours. Excessive heat had been engendered by the engines running at full throttle to support the great load, and a leak developed in the oiling system. The flight had been abandoned, and Flight Lieutenant Carr made a skillful landing at Martlesham aerodrome. Had such a trouble developed over the ocean, tragedy would have been well-nigh inevitable. When the Old Glory left Maine on a nonstop flight to Rome it was so heavy with fuel that it ran along the hard-packed sand of the beach for nearly two miles before it could rise in the air, for it carried 'a heavier load than any single-motored monoplane ever tried to lift before.' The wireless message received some hours later, 'The ship is heavy, but everything is going fine,' supplies the only clue to the disaster that ensued.

Thus the most difficult mechanical problem in these long-distance flights is the suspension of the great loads in the air against the natural force of gravity. Reflection shows that in no other form of transport is the propelling power expected to lift the vehicle and its load, in addition to propelling it forward. This being so, it is not surprising to find enormous horsepower installed to transport what is relatively an insignificant load. For a long nonstop flight much fuel is necessary; all the available load to the last pound must be taken in petrol, and vigilance and scrupulous care must be exercised to discard everything that is not essential to success.

When the Marchese cli Pinedo started from Trepassey, Newfoundland, on May 23, 1927, on his flight of 1500 miles to the Azores, he loaded up with petrol, and at the last moment decided to discard his wireless equipment, weighing 400 pounds, judging it safer to take the weight in fuel. Nevertheless it was not enough, for on the voyage he encountered such an adverse air current that his progress over the sea was reduced to 60 miles per hour and he saw his petrol would not last out. Fortunately before it was spent he sighted a schooner and was taken in tow.

Before the two Junker monoplanes Europa and Bremen started on their attempt to cross the Atlantic in August, 'everybody and everything belonging to the expedition was carefully weighed, and nonessential articles destined to comfort or sustain the airmen had reluctantly to be abandoned in order to keep the weight down to 3800 kilogrammes, of which some 2400 represent fuel.' Nevertheless the Bremen, which alone reached the Atlantic, was obliged to turn back, for as time went on Captain Kohl realized that his fuel would not take him to Newfoundland. 'It was useless to continue the struggle,' for the wind was westerly and he was making little or no headway in the adverse current. On his return to Germany Captain Kohl declared, 'If the weather had been merely bad I would have kept on, but I could not fight along at the rate of four miles per hour.' Yet this Junker monoplane was capable of covering 125 miles per hour, and was no doubt flying at this actual speed in the moving air.


The domination of the wind over aircraft is complete. An aeroplane in the air cannot use the wind. There can be no comparison between the action of wind on a sailing ship and the action of wind - moving air - on an aeroplane flying in it and completely surrounded by it. In the air there can be no 'trimming of sails,' no 'beating to windward,' for to all the courses of the air and to its full speed the aeroplane unconsciously and completely conforms. A 'sea' of air envelops it; within this moving 'sea' the airman unconsciously drives his plane and steers a course. His course over land or sea and his speed 'made good' are the resultant of known and unknown factors. Adequate provision can be made for the known factors, and should no engine trouble occur or compass errors develop, and were the 'sea' in which the airman flies as stationary as the sea or land beneath him, the airman must arrive at his destination and at the prearranged time; were even the movement of the medium known, and could it be relied upon not to alter in rate and direction during the whole journey, the time of safe arrival could be calculated beforehand; but should the aviator's 'sea' take some unexpected course during passage, the time of arrival is uncertain—in a long flight the end may never be known. The skill of the pilot cannot ensure success or avert disaster, for the wind is at the helm, imposing upon a craft its own direction and speed.

This can be as readily shown by simple arithmetic as it has been demonstrated in recent flights. Take a flight between two capitals separated by 3000 miles of sea, by a plane developing no defects, with an average speed of 100 miles per hour and a load of 40 hours' fuel at this speed. In a dead calm the destination will be safely reached in 30 hours with 10 hours' fuel remaining. In a directly favorable and constant wind of only 30 miles per hour (a very moderate wind at flying heights) the aeroplane, making 130 miles per hour, will reach its goal in 23 hours, the pilot will have 17 hours' fuel remaining in tanks, and, if he wishes, he can fly on in the same direction for 2200 miles and set up a new record.

It is absurd to reverse the conditions, for the airman would not set off; but, were he so rash as to start, he would, with the 30-miles-per-hour current directly against him, be obliged to come down or would fall into the 200 miles from his proposed destination. Thus, with the favorable wind he could cover 59,00 miles, with the unfavorable about 2800 only, —a difference of some 2400 miles,—nevertheless in neither case would he lose direction. If his compasses were correct he would land somewhere along the predetermined route of 3000 geographical miles.

A change of wind on passage, however, upsets all calculations. Should the 30-miles-per-hour favorable wind shift 8 points (90∞), say, 10 hours from the start, after he has flown 1800 miles he will have covered at the end of the next 10 hours some 1044 miles toward his destination, but will be, in the absence of external warning, 300 miles off his intended course. In truth he will be lost on the ocean, for the aeroplane itself, when fixed points are available, cannot detect changes in the wind and cannot therefore know the drift. Hence the constant anxiety of the navigator and the necessity of ascertaining the position of the aeroplane and its course from passing vessels at sea, and the reliance upon wireless from land or ship stations—a stay which may prove a broken reed.

The comments of the New York Meteorological Office after the successful flight of Colonel Lindbergh and that of Chamberlin and Mr. Levine merit special consideration. This bureau had been receiving weather reports twice daily from ten ocean liners by radio, and five hundred ships had sent their observations by mail. The report of the meteorologist is significant: —

There really have been only three times since April 20 when a transatlantic flight would have been safe. The first began, strangely enough, on the day that Acosta and Chamberlin started their endurance flight in the Bellanca. If they had taken off for Europe instead of circling over Manhattan, they would undoubtedly have reached it without any trouble. The second time when Lindbergh made his successful (May 20) and the third when Chamberlin took off (June 4).

Colonel Lindbergh was fortunate in his weather; and his luck in having the wind over the Atlantic, as he expected, was amazing. He trusted to a small compass and dead reckoning; his plans for navigation were simple: when he left the seaboard and America behind, following the steamer route, he would every one hundred miles (one hour by his watch) alter course. The weather was better than he expected, 'better than the Weather Bureau had expected.' He saw little during the ocean crossing and though the fog obscured his view, the constancy of the wind favored his dead reckoning. In the afternoon he saw some fishing boats.

Was he on the right road to Ireland? When he assured himself that 'it was Ireland rather than Spain or some other country, the rest was child's play.' That he came on the Irish coast just three miles from where he expected was 'a pure coincidence,' and a remarkable one.

Clarence Chamberlin and Mr. Levine placed reliance upon an earth-induction compass, but soon it sas 'running wild' and they were left with the ordinary magnetic compass. Icebergs helped in the estimation of drift, but when they had lost direction, and did not know whether they would hit Spain or Ireland, they luckily came upon the Mauretania and found that they were 'somewhere near Ireland or England.'

The Pride of Detroit was more fortunate in the wind than its airmen knew; when they reached land after crossing the ocean they 'hadn't any idea what country it was.' After flying about for two hours they inquired by primitive means where they were, and intelligent and resourceful coastguardsmen coastguardsmen, by promptly spreading out a Union Jack, gave the airmen the information they needed to make Croydon.

Were the wind and weather not the main factors in long flights, it would be inexplicable that 'the most experienced and careful navigator, Commander Byrd, and the best-equipped aeroplane, the America, should have failed to achieve what others had succeeded in accomplishing.' He, with three companions, left New York on June 29, and though 'conditions over most of the Atlantic were quite favorable,' the weather did not behave in accordance with expert forecasts, and the flight nearly ended in disaster. After reaching the French coast in safety, while darkness was setting in and the weather was getting rainy and thick, something went wrong with the compasses and the wireless failed to work. Commander Byrd found he was flying in a circle instead of a straight line, but whether to the right or to the left he did not know; his petrol was fast giving out and he decided to come down on water.

The United States Meteorological Report comments thus upon these three Atlantic crossings:—

Had Lindbergh encountered the cross winds that Byrd did, the Spirit of St. Louis would have been blown off her course as far as was the America, in spite of the perfect piloting of the man controlling her destinies; and had Chamberlin encountered the poor visibility conditions that hindered Byrd, it is almost certain that his courageous flight would have ended in disaster. To sum up, one may say almost everything depends upon the weather.


The effect of favorable air currents in successful flights, the value of dead reckoning while the wind remains constant in direction, the ceaseless dread that an unknown and therefore incalculable variation of current may occur, the fear of being carried away and lost in the air from drift, the race against time and fuel supply, the discomfort and danger of flying in fog or at freezing heights, the fickleness of wireless, the uncertainty of the 'landfall' in ocean flights, the obstacles to the recognition and choice of landing places—all these and other navigational hazards have been demonstrated in turn in all long-distance flights, which are and must remain 'hops for heroes only.'

The tragic fate of Saint-Roman and his two companions, and of Nungesser and Coli, had been overshadowed and almost forgotten in the brilliant success of Colonel Lindbergh and the exploits of Chamberlin and Commander Byrd; but as the flying season progressed tragic failure followed tragic failure and the adventures that succeeded only showed in clearer light how much weather and wind and sheer luck were the determining factors of triumph or disaster. During 1927 the North Atlantic has been crossed four times in nonstop flights; twice only, did the pilots arrive and land safely at the intended destination and without mishap, and twelve lives were lost in disastrous ventures. During the year the Pacific has been traversed by air from California to Honolulu four times, three times without mishap, while seven perished in attempting this ocean crossing and three were killed in preparatory flights. The causes of failure in the many disasters over the seas will forever remain hidden. Saint-Roman, Nungesser, Frost of the Golden Eagle, Pedlar of the Miss Doran, Redfern, Colonel Minchin, Lloyd Bertaud, Captain Tully, and their companions have left no trace. The SOS of Captain Erwin,

We went into a tail spin... We have come out of it... It was a close call... We are in a spin... SOS...

points to the peril that is ever present in flight. It will never be known whether the tragedies were brought about by engine failure, overloading, lubricating trouble, or some mechanical defect, by adverse winds, shortage of fuel, or loss of direction, or by sudden movements and violent upheavals of the air which are the concomitants of thunderstorms and unstable weather conditions. The efficiency of the machines in the successful flights and the testimony of pilots show the perfection to which the internal-combustion engine has attained, but in the air a trifling mechanical defect may lead to precipitate disaster, for an aeroplane, to keep in the air, must keep going.

All the long-distance flights had started in favorable weather, for ships at sea were sending special reports so that the forecasts could be made with as much accuracy as possible. Moreover, the ships crossing the oceans were warned of the intended flights and asked to report passage and render assistance if necessary. As events proved, ships had as much to do with these long-distance flights; and the stability of ships on the sea, their perfection of navigation, their reserve of fuel and power, their true mobility, their capacity to succor, are in striking and ludicrous contrast to the frailties and limitations of air machines.

The Pacific Fleet organized a search for the victims of the Dole Race. After the search a report was submitted by Admiral R. H. Jackson, Commander in Chief of the Battle Fleet. According to this report the flagship Holland, one light cruiser, twenty-three destroyers, two aircraft carriers (with many planes), twenty-three submarines, and three tenders of the Pacific had searched an area of 350,000 square miles. They had steamed 153,235 miles, the planes had flown 9000 miles, and 3,751,050 gallons of fuel had been consumed. It is true that some small proportion of this search could be classed in 'schedule operations,' but the figures given do not include the extensive search operations by district craft carried on under the supervision of district naval commanders or the search by ships of the mercantile marine.

Again, when the Old Glory sent out the SOS message, four vessels took took in the signal—the Transylvania, the Carmania, the Lapland, and the California. The first two of these great liners were nearest to the estimated position of the plane, and altered course at once in search. Captain David Bone and the officers of the Transylvania kept a strict watch on the horizon for over fifteen hours and zigzagged over an area where it was supposed the Old Glory dropped into the sea. 'During all this time fourteen Lookouts with binoculars and telescopes tried to find some trace.' All these ships and other vessels cooperated and different areas were searched—all to no avail. Trying to find an aeroplane in the ocean was like looking for a needle in a haystack, and after twenty-four hours there was little hope of possible survival in view of the rough seas at the time of the forced descent. The cost of this fruitless search by these great liners—entirely ignoring the passengers' loss of time has been estimated at £4000; but ships are in duty bound to endeavor to save life at sea, with no remuneration except in value of the material saved. Some nine days later the S.S. Kyle, detailed for special search, came upon wreckage 650 miles due east of Newfoundland; of the unfortunate aviators no sign was seen.


At last the futility of long-distance flights, with the sacrifice of lives toward no end, was amply demonstrated. Facts could no longer be ignored. What should have been known, what could readily have been foreseen, by giving thought to the problems, was now manifest. The reaction was immediate. A conference was called at Washington, President Coolidge was deeply concerned, the American Bar Association demanded legislation, the Australian Commonwealth decided to take action, and the Canadian Government proposed to introduce legislation prohibiting ocean flights. Agitation spread. The press in America and Europe discussed the tragedies and the wisdom or necessity of controlling ocean flights; newspapers spoke of 'the mobs that made heroes of Lindbergh and others,' 'the lavishly advertised performances of aviators acclaimed for their self-devotion to death.' 'Why do people not ask themselves what is the use of it?' 'Has one of these flights contributed in the slightest degree to the success of the next one or added one iota to the progress of aviation?' Some who had been loud in applauding the initial successes as proofs of the conquest of the air were now censuring the waste of life and courage, and insisting on the limitations of the aeroplane and on the influence of the wind, maintaining that the successes were due to the concurrence of good luck and good weather, that flights in which disaster is narrowly escaped through good fortune teach the world little. Public opinion, which was being educated toward 'airmindedness,' was held largely responsible for the tragedies!

The aeronautical correspondent of the Times of London said:—

These flights of the Atlantic are simply the result of a public opinion, which shortsightedly has awarded praise out of all proportion... and the remedy lies in that same public opinion positively discouraging brave but foolhardy men from gambling their lives against the chance of a short-lived notoriety.

The British Air Ministry, 'after mature consideration,' said little; its attitude was noncommittal—'it would not be wise to interfere.' The position was indeed difficult, for the Air ViceMarshal, Sir Sefton Brancker, Director of Civil Aviation, had expressed his opinion in no uncertain terms after the loss of the St. Raphael:—

The flight from East to West has to be done, and it is idle to talk of prohibiting the attempt. Courage, courage, courage, should be our motto... Do not let us always be playing for safety. I could have put money on Minchin getting across safely.

And Lord Thomson, late Secretary of State for Air, had proclaimed in January 1927 that sensational nonstop flights had 'great practical value,' that the entire future of British aviation was summed up in two words, 'long hops,' that 'with the advent of "long hops" aviation will begin to assert itself as a means of locomotion and will acquire full commercial status.' This exponent of the air was frankly alarmed:—

I am afraid it is going to do harm to aviation... I don't like some of the things that are happening... I am particularly against the carrying of passengers.

As a London newspaper expressed idea the next day, 'The effort should be made unhampered by passengers who serve no useful or desirable purpose.' Fuel is indeed the only freight for long-distance flights. It had at last become manifest that these ventures had no bearing upon the development of aerial transport. It was nothing but a gamble, with human lives as the stakes and the dice loaded—doubly loaded—against the flyers toward the West.

The aeroplane had demonstrated its deficiencies and its inherent limitations gravity had shown the force of its grip and wind the power of its embrace, but the public were not left to ponder on these things. No sooner was the illusion dispelled than another one was projected. 'The flights have been attempted in quite unsuitable machines'; 'Ocean flights ought not to be attempted in landplanes'; 'What is wanted to-day is safe flying'; 'Seaplanes should be used for the sea-flying boats for the ocean.'

Machines are needed which are so staunchly built of metal that they would survive even if they came down on the water in rough weather. Sea craft should be able to ride out a storm. They further require wireless powerful enough to summon help in the event of any mischance; they must have multiple engines and carry a very large quantity of petrol in order to avoid the risk of fuel failure if adverse weather and winds are encountered or if direction is temporarily lost.

No one can find fault with these requirements; they are the elementary essentials for safety; but a little reflection will soon destroy the illusion that such conditions are possible. The law of gravity makes no distinction between an aeropIane and a flying boat: modifications in design can readily be made in accordance with the purpose for which the plane is desired, variation is made in the distribution of the load, but the maximum load that can be lifted for any engine power is the same. The stronger the seaplane is made in an effort to attain seaworthiness, the heavier will be its structure and the less weight remains for fuel, for wireless, or for crew: if a powerful wireless is taken, still less fuel can be carried; with little fuel the voyage is strictly limited. The carrying of an anchor is no light matter. A seaplane must take this gear with her and lift it into the air. The heavier it is, the less fuel can be carried; if it is too light, the safety of the craft is endangered.

Seaplanes cannot be used for long-distance flights. It will be remembered that the seaplane flown by Commander Rodgers in 1925 in the San Francisco-Honolulu flight came down 200 miles from Honolulu for want of fuel. The first successful crossing, in June 1927, was in an Army aeroplane, and Lieutenant Maitland reported that 'sufficient gasoline for another 600 miles' was left in his machine. Again, the first nonstop crossing of the South Atlantic was achieved by aeroplane. On October 15, 1927, two French lieutenants, Costes and Le Brix, flew the shortest sea passage, a distance of 2000 miles, in 21 and a quarter hours. All the previous crossings had been accomplished by stages in seaplanes.

The opinions of naval men can well be quoted here. Admiral Sir W. H. Henderson, putting the matter in a nutshell, says: —

The seaplane or flying boat offers a chance of a few hours of life to derelict airmen, but, conversant as I am with Atlantic weather conditions and the difficulty of locating an aeroplane in an ocean, I would prefer to trust my life to the extra fuel possible in a landplane.

Commander F. L. M. Boothby, R.N. (Retd.), reminds the public that

The flying boat, advocated by some, is at present less efficient than the aeroplane in the air and slightly more so on the water. A sea that would rapidly break up an aeroplane could be ridden out by a flying boat, but it would last next to no time in an ordinary heavy sea.

In the opinion of Admiral Mark Kerr,

It is unlikely that the biggest flying boat of the present time would last more than a few hours on the Atlantic on 300 days of the year.

Seaplane services are being tried out. A transport company essayed a mail service on the Khartum-Kisumu route with a seaplane, the D. H. 50 Pelican. It was damaged in a test flight in January 1927, and the Air Ministry lent the company a seaplane while the Pelican was being repaired. But this borrowed seaplane promptly sank in Lake Victoria Nyanza. At last, on October 9, the Pelican was prepared to resume its work, yet no sooner were air-mail facilities announced than they were suspended—the Pelican had crashed a second time in a test flight.


It is generally recognized that air machines, wonderful as they are, are still far from being satisfactory; that especially in weight-carrying capacity there is room for radical improvement. Any criticism, however, of the shortcomings of aircraft or any statement of their inherent limitations is met at once by the retort that 'aeroplanes are in their infancy'; that, given time and money for experiment and research, difficulties will be overcome, 'the air will be conquered.' Repeated disappointment and dreadful tragedy are met by the plea that aeroplanes are not yet properly developed, the study of aerodynamics is not sufficiently advanced—and the public is persistently led to expect great improvement in aeroplanes and much practical advance in the art of mechanical flight.

But consideration of the matter will show that flight became possible only after the introduction and development of an engine of light weight per horsepower,—the internal-combustion engine, —and that this engine, continuously improved and developed during the last thirty-five years, has now in all vital respects reached its limit of perfection. All engineering knowledge accumulated since the dawn of the mechanical age has gone generally to the design and construction of the aeroplane as it is to-day; twenty-five years have been devoted to this specialized branch of engineering—mechanical flight. All of the body of knowledge from the common stock has been available and intensively applied to the development of aviation, at fabulous cost to the taxpayers of all nations.

Engineers and experts are agreed on the point that the aeroplane has long passed its experimental stage. Sir Alan Cobham, the famous long-distance pilot, referring to his Australian flight, says, 'From a mechanical point of view the aeroplane was as near perfext as any form of transport can be,' and neither Colonel Lindbergh nor Mr. Levine had any failt to find with their engines or with their planes—albeit their engines were not new types, and were of designs that had been years in use. Major de Havilland, a well-known manufactuerer, states:—

There is no revolutionary change to be expected in aeroplanes. Design is more or less stabilized, and it is only in details, in materials, in strength and lightness, that any alteration may be looked for.

The maximum weight that an aero-engine can lift and carry is practically fixed. The engine itself is light; the big factor, apart from the weight of the plane itself, is the fuel it requires. In a long, spectacular flight all the available load must be taken in fuel to cover the distance; no freight can be carried; all but the barest necessities must be left behind. Paying freight can only be taken when the distance is strictly limited: the shorter the distance, the less fuel required, and the more weight left for freight. This at once shows that the aeroplane, for any practical purpose, is a short-distance vehicle of transport. Moreover, common sense indicates and experience proves that, if safety is aimed at, the structure of the vehicle should not lack strength and the limit of loading should not be approached; if comfort is desired, some part of the paying load must be sacrificed. All these factors further reduce the load of fuel that can be carried, the distance that can be covered. 'As a matter of common knowledge,' states the Secretary-General of the Air League of the British Empire, 'a commercial machine carries but little more than the maximum paying load. Moreover, both passenger and freight are carefully weighed in order to ensure there shall be no overloading.' When strong adverse winds are encountered the restricted amount of petrol carried may not last out and a forced landing becomes inevitable. For the air journey of some 200 miles on the cross-Channel service, when weather conditions are not too adverse, twelve to fourteen persons are carried by the new large passenger planes with engines developing 1200 horsepower. It is worth contrasting the useful achievement of a similar horsepower when relying on gravity instead of resisting it. A great train rushing smoothly and swiftly along rails, irrespective of weather, at a rate comparable to the speed of a heavy aeroplane, presents the most startling contrast in effort and achievement. The famous railway engine King George V can run, it is said, at nearly 100 miles per hour and draw 'almost any load.'

It is not difficult, therefore, to understand why the 'air' cannot compete with older and cheaper forms of transport—why aviation fails to pay its way. Colonel Lindbergh, speaking on the commercial aspect of the air mails in the United States said:—

Our mail service is in a few cases on a paying basis. By a paying basis I do not mean that there is any margin, any large margin of profit. Most of these air lines are just about holding their own or losing a little each year.

Air mails are thus not very profitable in the contractors. The expense of United States air-mail service ending June 30, 1926, was $2,944,648. The total receipts for the same period were $980,271:—A loss of $1,964,377 chargeable to public funds. For each ounce of letter mail carried by air mail from Boston to New York the contractor is paid over eighteen cents; twenty cents is paid by the sender, and government subsidy supplies the balance.

All existing air routes, indeed, are dependent upon subsidies. If they were cut off, civil aviation would practically come to an end. The cost to the British taxpayer of every mile flown by Imperial Airways on home routes is 3s.4.5d., or £70 for the return journey Croydon-Paris: on the route Cairo-Basra every mile costs the taxpayer £1, or £1200 for each completed flight; and in addition further aid is given in the provision of landing grounds, petrol stations, and sheds. Germany has a network of air routes, but 70 per cent of the cost of German aerial transport has to be obtained by taxation or subsidy, this assistance amounting to the enormous sum of £2,137,000 yearly; and though each passenger receives free insurance with his ticket, and other encouragements to air travel are given, the machines, it is said, usually leave half full. The subsidies paid by France to aviation companies have aggregated 60,000,000 francs, yearly payments being based on mileage, and additional help has been given through the purchase by the Government of new types of machines destined for civil purposes. In October 1927, the French Government resolved to ask the Chamber to sanction further expenditure which will commit it to spending 140,000,000 francs, or $5,650,000, a year on civil flying for a period of ten years.

Leaving profit out of the question, how is the gulf between subsidy and solvency to be bridged? How is commercial success to be achieved for aviation? It is not by further development of the aero-engine, for that has practically, if not quite, reached its limit; not by increasing the size of the planes, for no real saving is thus effected, except in pilots. Engines are as reliable and aeroplanes nearly as perfect as they can well be; external aids are now supplied in plenty, and aerial pilots are expert, ready, and resourceful. Though small improvements will undoubtedly take place, there can be no specific increase in performance. For any spectacular improvement we must await some quite new discovery—some new phenomenom, upon the nature of which it is idle to speculate. It involves a new source of motive energy, any energy which implies little or no weight, but gravity will still exercise its unfailing force, and the wind will continue to be beyond the control of man.

As things are, flying is too expensive a mode of transport to be considered by the ordinary man or woman. To the great majority with means, the deafening roar of the engines, the sense of danger, the great uncertainty, added to the not inconsiderable fare, more than balance the possible gain in time. There remain the few with the desire and the means to travel by air, which they do at considerable cost to the State.

Under special circumstances for emergency transport, aeroplanes may be of great service. Banks find aeroplanes useful for the carrying of bullion across the Channel and between cities not too far apart, but the real advantage or desirability of these and other services can only be tested when state subsidy ceases and civil aviation flies by itself. In undeveloped countries, where other means of rapid transport are not available and where flying conditions are good, aeroplanes may prove of distinct value, and their use justified in providing medical aid and communications to 'back blocks'; they do it, however, at a cost which must entail considerable assistance from public funds.

The poverty of the demand on the part of the public for aeroplanes as vehicles of transport is a perpetual disappointment to those interested parties and leagues who are concerned in creating what is termed 'air-mindedness' among the people. Even the sport of flying is not carried on without government encouragement, and the race for the Schneider Cup has now become a contest between Air Ministries and a further addition to the heavy burden of taxation.

Though subsidies now support aerial transport in every direction, and propaganda seeks to popularize it, eventually civil aviation must be left to fly by itself; and, while economic factors determine its scope, the aeroplane will remain a vehicle of emergency and quick transport under conditions favorable to its use, reasonably safe for comparatively short distances, perilous on long flights, with freedom of route denied to other vehicles of transport, yet governed in its incomings and outgoings by the inconstant wind. But the force of gravity ever pulling the plane and its load to Earth will ever set a limit to the achievements of aircraft and be the insurmountable barrier to commercial success in the air.