THE ATMOSPHERE AS A HIGHWAY
Within the last few years the atmosphere has assumed a new and
tremendous importance in human affairs as a medium that affords
facilities for travel and transportation far superior, in many
respects, to those offered by the land or the water. The aerial
highways are now open for business and pleasure. This is a fact that
the majority of people find it difficult to realize. The navigation of
the air on a general scale has so long been looked upon as a dream of
the future that we cannot readily adjust our minds to the reality.
The story of the slow steps by which this momentous fact has been
brought to pass is far too long to be told here. What we purpose to
do in the present chapter is to sketch the multifarious uses to which
man is now applying the aeronautical knowledge and skill that he has
acquired. At the same time we shall anticipate, to some extent, the
developments of the near future; for the lines of progress are so
clearly marked out that it is possible to do this without giving too
much rein to the imagination.
In a subsequent chapter, dealing with Aeronautical Meteorology, we
shall touch briefly upon the mechanical principles that underlie aerial
navigation, by way of preface to a more detailed description of the
conditions of wind and weather encountered by aircraft, and of the
services that the meteorologist is rendering to the aeronaut.
The history of aeronautics may be divided into two periods, with the
year 1914 as the dividing line between them. Before the great war
the many brilliant minds that were trying to solve the problems of
aerial navigation received comparatively little help or encouragement
from humanity at large. The airship and the aeroplane were both
accomplished facts, but most people looked upon them as ticklish
contrivances of very little practical value. From the year 1909 onward
aviation occupied an immense share of public attention; liberal prizes
for aerial feats were offered; new records for speed, altitude, and
endurance were made from day to day; but to the public, and perhaps to
most of the aviators themselves, all this meant merely that a new and
thrilling sport had been created, rather than a new art of boundless
utility. Very few business men felt inclined to invest money in the
development of aircraft, and the governments of the leading nations,
with a single exception, were incredibly blind to the importance of
building air fleets for use in war. The exception was Germany, which
not only gave strong support to Count Zeppelin in the building of his
dirigibles, but developed military aviation to such an extent that she
entered the war with about 800 aeroplanes and a thousand trained pilots.
With the outbreak of the war the budding art burst into vigorous bloom.
Unlimited funds were now available for experimenting and building.
Thousands of flyers invaded the air, and the battle zone was a testing
ground on a vast scale, where one improvement was hardly introduced
before it was replaced by another. Some of the best engineering talent
of the world was diverted from many and various fields to the one task
of supplying the demands of the military aeronauts for more speed, more
power, more reliable motors, better materials and appliances. Thus the
war not only perfected aeronautics--especially aviation--as an art,
but practically created it as an industry. At the close of hostilities
the world found itself in possession of a vast fleet of aircraft, a
multitude of aircraft factories, and a great army of trained aeronauts.
For a time people asked--and perhaps some still ask--“What shall we do
with them?”
There are many answers to this question, and new ones are coming to
light every day. In the aggregate they mean that a new era has dawned
in human affairs--the era in which the sky has been annexed to the
world in which man lives. Henceforth we shall have more elbow room. We
shall no longer be imprisoned in Flatland, but set free in Spaceland.
It is impossible to foresee all the implications of this fact, but
those that are already apparent suffice to fill us with enthusiasm.
Some of the most vexed problems of the present day will soon be
solved by aerial navigation. Take that of our overcrowded cities.
Everybody knows how first the trolley car and then the automobile
helped to relieve the congestion of towns by making it feasible for
people to live many miles from the scenes of their daily work, but
at the same time seriously swelled the traffic of the streets in
business quarters. Aircraft will bring far greater improvements in
this respect, without corresponding disadvantages. In a few years it
will probably be no inconvenience to live fifty or a hundred miles
from one’s place of business. Aeroplanes, built for carrying several
passengers in perfect comfort, _already_ fly at speeds of from 120
to 150 miles an hour, and are almost independent of weather. Much
greater speeds will doubtless be common in the future. Automobiles,
all running on the same level, have almost reached the limit of space
available in our busiest streets, and, under such conditions, they
have nearly lost the advantage of speed they once possessed over the
obsolete horse-drawn vehicle. There can never be such crowding in the
air. When a great volume of aerial traffic is concentrated toward the
centers of towns, people will fly their vehicles at various prescribed
levels, and probably “park” them on many-storied landing stages. New
methods of landing will undoubtedly be invented. The device known as
the “helicopter,” which has made progress toward the practical stage
during the past year, points out the possibilities in this direction.
In the helicopter the propeller blades revolve around a vertical shaft,
thus permitting the vehicle to rise or descend vertically. A prize
of $100,000 has recently been offered by M. Michelin, the well-known
French patron of aviation, for the perfection of this device, which may
soon revolutionize the design of flying machines.
Mr. Holt Thomas, the Englishman whose foresight and enthusiasm have
done so much to hasten the arrival of practical commercial aeronautics,
believes that in the near future the main airways of the world will be
served by airships rather than by aeroplanes. For long journeys the
airship has the advantage that it can carry an ample supply of fuel
without encroaching too much upon the space available for passengers
and cargo. It is, therefore, especially suitable for transoceanic
journeys. Hitherto airships, when not in flight, have been housed
in enormous hangars, involving heavy cost of installation and their
landing has required the services of hundreds of men--an operation that
will probably seem laughable in its crudity to the next generation.
The airship of the future will probably never go into a hangar at
all except for occasional overhauling, as an ordinary ship goes into
drydock. Hence only a few of these costly structures will be needed.
While in service the airship will, on reaching an air port, moor
herself at the bow to a great steel tower, and swing with the wind as a
marine vessel swings at her anchor. At the top of the tower there will
be a landing stage for passengers and freight, connected by lifts with
the ground below. From the main air ports, thus equipped, will radiate
minor air routes, served by aeroplanes, and, in some cases, by flying
boats.
Such landing places for airships were predicted by Kipling in his “With
the Night Mail”--but the author’s vista was of the year 2000! We are
not traveling so slowly as that. Consider what it means that the world
heard with bated breath of Blériot’s flight over the English Channel in
1909; and just ten years later men had flown over the Atlantic Ocean.
We have been writing of the future; but we need not look ahead for
illustrations of the practical value of aerial navigation. Useful feats
already accomplished are so astonishing in their variety that they
make one cautious about assigning a limit to the possible applications
of the new art. It has happened, for example, that a man who had
booked passage on a trans-Pacific steamer missed his boat at Seattle;
whereupon he hired an aeroplane, at a cost of $75, and overtook the
steamer on her way down Puget Sound, thus saving some weeks of delay
in waiting for the next one. Another man, who produces honey on a large
scale, found that spray-poisoned orchards were playing havoc with
his bees. He traveled in an aeroplane over the surrounding country,
selecting stands for his hives at safe distances from such orchards,
and he estimates that this precaution saved him $10,000 in a single
year. In August, 1919, a flying boat deposited a bag of mail on the
White Star liner _Adriatic_ two hours after the ship had left New York.
Several aerial mail routes are now in operation on both sides of the
Atlantic. The first regular service of this character in America
was begun May 15, 1918, between New York and Washington, and during
the first year carried 7,720,840 letters, with few accidents and no
fatalities. The first year of service cost the Government $137,900,
and the sale of aeroplane mail stamps during the same period yielded a
revenue of $159,700. Out of 1,261 possible trips on this route, 1,206
were undertaken, and only fifty-five were abandoned on account of
unfavorable weather. During 1919 the Post Office Department not only
established other aerial routes, but relegated the aerial mail service
to the ranks of the commonplace by reducing the postage on letters
carried by aeroplane to the ordinary first-class rate of two cents an
ounce.
In Europe lines of fast aeroplanes carrying mails, passengers, and
freight daily over regular routes are becoming part of the established
order of things. The operators of a line between London and Paris,
which was inaugurated in November, 1919, are now planning to establish
an hourly service. Some of these lines have been equipped with wireless
telephony, so that the pilots can keep in constant communication
with numerous stations of the company along the route, and also
with one another. They are thus able to obtain, among other things,
current information about the prevalence of fog or other atmospheric
conditions at points ahead of them. Presumably the passengers who
patronize the aeroplane express will also, eventually, enjoy the use
of the wireless telephone _en route_. In connection with the new air
routes suitable landing grounds, for regular or emergency use, are
being laid out at short intervals; the ideal aimed at, for the present,
being the so-called “ten-mile chain”; i. e., a series of emergency
landing grounds about ten miles apart. From ordinary flying levels a
pilot on such a route can always glide to one of these grounds in case
his motor fails. The landing grounds will be utilized, under certain
restrictions, for grazing cattle and for agricultural purposes, to
help cover the cost of rental and maintenance. During 1919 the British
Government established a chain of landing grounds in Africa, all the
way from Cairo to the Cape.
One of the developments of the war was the use of aeroplanes for
photographic mapping. The aeroplane flies over a long tract of ground,
and the camera, exposed vertically, takes pictures automatically
at fixed intervals. The pictures thus taken are carefully joined
together in a single strip. A second tract, parallel with the first,
is photographed in the same manner, and so on, until the whole area
has been covered. Eventually all the pictures are assembled to form
a so-called “mosaic.” This process is highly successful for mapping
a flat country, but presents difficulties when there are hills and
mountains. Some sort of stereoscopic process will probably be
perfected for depicting accurately differences in level and producing
a “contoured” map. Although aeronautical mapping does not yet replace
old-fashioned methods, it already has several obvious uses. It is
especially suitable for the revision of existing maps. Thus the plan
of a city can be quickly brought up to date by this process. In the
United States the Geological Survey has been engaged for many years in
producing large-scale topographic maps of all parts of the country.
This work proceeds slowly, and some of the maps are ten or fifteen
years old. The contours and other natural features on such a map are
still correct, but changes in the region due to the work of man are
often extensive. Revision of these features can easily be made by the
method above described.
For the preliminary mapping of a new country, by photography or by
hand, the aeroplane offers the means of saving an immense amount of
time and effort. The surveyor no longer needs to cut tracks through
the jungle or scale mountains. No region is very difficult of access
to the aviator. The summit of Mount Everest, the highest mountain
in the world, is actually a mile lower than the greatest altitude
attained by an aeroplane. Aviation has become an important feature of
exploring expeditions. Captain Amundsen, the polar explorer, qualified
as an air pilot before he embarked on his drift across the North
Polar basin, and took aeroplanes with him on that journey. In India
the Survey Department has organized a regular aerial photographic and
reconnoissance service, and has lately photographed the high waters
of the River Sutlej in order to obtain data for a big electrification
project. Photographs of the Nile country have also been made for
hydrological purposes. British aviators in Mesopotamia have mapped the
flood boundaries of the Tigris and provided data for estimating crop
areas. In the Philippines an engineer recently made a long aeroplane
flight to determine which of three general routes was most suitable
for a new railway. Many months of time and thousands of dollars were
thus saved, as it was only necessary to send out one party of locating
engineers instead of three after the selection had been made.
Recently the aerial surveyor has become the rival of the hydrographer
in mapping shoals, channels, submerged rocks, and other features
beneath the water. If the water is clear and suitable atmospheric
conditions prevail, objects submerged to a considerable depth may be
distinctly seen from an aeroplane flying far above the surface. It
was on account of this fact that Allied aviators were able to spot
submerged German submarines during the World War. The camera, equipped
with proper plates and ray filters, can pierce the water even better
than the eye. Thus objects have been photographed at a depth of more
than 50 feet. British aviators charted the harbor of Rahbeg, on the
coast of Arabia, by the process in 1917. In this country the leading
exponent of underwater photography is Dr. Willis T. Lee, of the United
States Geological Survey, who has taken scores of photographs showing
submerged features of the waters adjacent to Chesapeake Bay. It is
likely that rivers like the Mississippi, with ever shifting sand bars,
will soon be made safe by monthly or weekly mapping from the air. In
earthquake regions, such as southern Italy and Japan, the changing
coast lines, shallows and harbors can easily be photographed after
each new quake, thus keeping navigation open and protecting the lives
of mariners.
Another application of this process of sighting submerged objects from
the air is the aerial fish patrol. The plan of using aircraft to locate
schools of fish appears to have been first suggested by Professor
Joubin, of the Oceanographic Institute of Monaco, and it has been
carried out with much success in both Europe and America. Its promoters
hope that it will eventually revolutionize the fishing industry and add
greatly to the world’s food supply. In the year 1919 seaplanes from the
North Island Air Station at San Diego, California, made regular flights
at an altitude of about 500 feet over the adjacent waters as an adjunct
to the important fisheries in that vicinity. When a school of fish was
detected, the aviator dropped low enough to ascertain the species,
and if it proved to be of a commercial kind, such as the sardine, the
news was flashed by wireless to the fishing fleet. The ocean in the
neighborhood of San Diego was divided into numbered squares, shown on
charts, and locations were reported by number. In 1920 a daily patrol
was maintained by Navy seaplanes over the waters of Chesapeake Bay in
behalf of the menhaden fishery. According to an official report, “the
experiments fully demonstrated the commercial value of planes in this
fishery.” It is believed that aircraft might be used with equal success
in connection with the whaling industry.
The United States Forest Service has made considerable use of Army
aeroplanes and aviators in patrolling the great forests of the West,
where a constant lookout for fires must be kept throughout the summer.
There are about 28,000 forest fires in this country every year, and
the average area burned over amounts to more than 8,000,000 acres,
entailing an average annual loss of $10,000,000 worth of timber.
Observations are maintained on mountain peaks and towers, but the
aerial watchman commands a much greater range of vision and can readily
detect fires in places such as deep canyons where they are, in many
cases, hidden from the existing lookout points. When a big fire is
in progress, the aviator can quickly ascertain its extent and report
the information by wireless to the fire-fighting forces. In case the
fire is difficult of access on account of the absence of roads, the
fire fighters can be transported to the spot in aeroplanes. It has
even been proposed to fight forest fires by dropping bombs filled
with fire-extinguishing chemicals. At one time it was thought that
aeroplanes might largely replace fixed lookout stations, but experience
shows that both systems of observation are desirable. Many foresters
favor the use of small dirigible airships in place of aeroplanes, owing
to their ability to fly very low, when desired, land in any small
clearing, discharge passengers by rope-ladder while hovering over a
selected spot, and transport relatively large loads of men and supplies.
Such are a few of the valuable peace-time uses that have already been
found for the aerial vehicles that owed their production chiefly
to the late war and for the host of pilots trained during the same
conflict. Undoubtedly the immediate future holds far more interesting
developments in store.
One important practical aspect of aeronautics remains to be mentioned,
and that is the question of safety. In their early days the steamboat
and the steam railway were both risky contrivances. It is recorded
that at one time steamboats were barred from the Thames on account of
their dangers. Undoubtedly the tradition of frequent boiler explosions
lingered in people’s minds long after it had ceased to be a substantial
fact. Aerial navigation--and particularly aviation--has now passed
beyond the pioneer stage, but it still bears the dubious reputation
that it acquired when it was in its infancy. Aerial travel, under
standardized conditions, is no longer unsafe. There are good reasons
for regarding it already as safer than automobiling. According to a
report of the British Department of Civil Aviation, there were 21,000
commercial flights in Great Britain during the six months from May 1
to October 31, 1919, and 52,000 passengers were carried. The total
mileage covered was 303,000. Not a single passenger was killed during
this period, and only ten were injured. There were two fatalities among
pilots and six pilots were injured.
Commander Read, who made the first transatlantic flight, writes on this
subject:
“There are some pilots with whom I would refuse to risk my life.
But, given a modern machine with the proper attention paid it, and a
skillful but conservative flyer, it is as safe a means of rapid transit
as an automobile traveling at less than half the speed. Nowadays there
is scarcely ever an accident in an aeroplane of standard type due to
the fault of material; they are all due to the inexperience or to the
dare-devil stunting proclivities of the pilot--the pilot who ‘takes
chances.’”
Aeronautics is now more than an art. It is a rapidly expanding branch
of applied science. Aeronautical engineering has become one of the
recognized professions. Some of the leading government laboratories
of the world, including the National Physical Laboratory in Great
Britain and the United States Bureau of Standards, are devoting their
attention to aeronautical research. There are also many unofficial
“aerodynamical” laboratories for studying, with the aid of wind tunnels
and other apparatus, the many problems pertaining to the physics of
flight and the principles of aeroplane designing.
Aeronautical questions have begun to figure conspicuously in
jurisprudence. Legislators, as somebody has said, are busy making
vertical laws to supplement the old-fashioned horizontal ones. In
international law, especially, aerial navigation has given rise
to thorny problems and it is already the subject of elaborate
international agreements.
The physiological effects of flight and altitude have added a new
chapter to the science of medicine. Seasickness has been the crux of
the ship’s doctor; will “air sickness” prove equally baffling? What are
the therapeutic possibilities of flying? Will physicians advise their
patients to seek a “change of air” vertically instead of horizontally?
The atmosphere, once monopolized by the birds, has become the abode
of man. That is one excellent reason why everybody should acquire a
knowledge of meteorology--the science of the air.