EUROPEAN AIR TRANSPORT this country civil aviation began to be developed immediately after the War, and since 1919 large sums have been devoted each year to air transport development. In 1927, four air transport companies operating over 8,304 route miles, had connections between London, Paris, Berlin, Brussels, Bucharest and other large cities of Europe and North Africa.
An outstanding success was achieved early by the line from France to Morocco over which mails have been transported since 1919. In 1934 the country's routes had been extended to 21,295 miles, and mail loads had increased to 216 tons. Like the British and American operators, the French extended their systems far beyond their own country. About fifteen years after the first French service was established between London and Paris, this country's transports were flying across Asia to Indo-China, over a great portion of Africa and were the first to establish regular aeroplane service across the South Atlantic, this route running from Dakar on the African coast to Natal, Brazil, and thence to Rio de Janeiro and Buenos Aires.
The keen rivalry between these two groups developed after a time into harmful competition and duplication, and the Govern ment was forced to step in. The obvious solution was the forma tion of a single company, and on April 1, 1926, the Deutsche Luft hansa was brought into existence, and in a few years had estab lished 14,000 miles of routes radiating from Berlin to the prin cipal cities of Europe with connections to Turkey, Persia and North Africa.
The Graf Zeppelin accomplished much route pioneering for Germany in the lighter-than-air field, notably with its many flights—most of them on regular schedule—from Friedrichshafen to South America in 1933 and 1934. These trans-Atlantic jour neys were to lay the foundation for a more firmly established German zeppelin service to South America with bigger and more powerful dirigibles after the Graf Zeppelin was taken out of commission.
excellent figure considering that the United States operators flew almost eleven times the distance covered on British routes, which rank second in mileage.
Bad weather has been responsible for most of the unscheduled landings by commercial transports, a rough percentage for the world being about 65% due to weather and 35% to mechanical failure. Schedule performance, however, is improving steadily everywhere with improved and new navigational communications and weather forecasting equipment and improvement in engines and craft design.
Improvement of Commercial Aircraft.—The problem of reducing the operating cost to cheaper commercial rates repre sents the most important question before the designers of com mercial aircraft. Progress is being made on, broadly, two main lines—the reduction of maintenance costs and the increase of paying load per horse-power. Air-cooled engines have come into wide use ; all-metal construction is generally replacing wood and fabric. Each and all of these innovations appreciably reduce the cost of operation.
Various mechanical developments are being applied to increase the disposable load without adding to the weight and size of the aircraft itself. The greatest load which an aircraft can carry is that with which it can take off and land safely. Once at a safe height in the air, the normal aircraft has plenty of lifting power in hand. Considerable increase in horse-power is being obtained without serious additional weight by means of various systems of supercharging or "boosting" aircraft engines. Variable pitch propellers were perfected about Permitting use of greater horse-power for take-offs with heavy loads and better speed at various flying altitudes.
Cleanliness of design of craft has been one of the most note worthy advances in aeronautics. The trend, particularly in the United States, has been toward monoplane construction of canti lever wing design, permitting elimination of outside structural bracing and other elements of "parasitic" resistance. With cleaner designs and improved engine performance speeds increased tre mendously, some American transports regularly approaching cruising speeds of 200 miles per hour. Cleaner designs, however, meant increased landing speeds and to offset this disadvantage "wing flaps," usually attached to the lower trailing edge of the wing, were developed and brought the ratio of flying speed to landing speed to about 31 to I by Speeds were slower over most of the European routes, although in the case of craft of Imperial Airways aeroplanes had to be designed for very slow landings due to lack of landing areas in the East sufficiently big for faster planes. British and European craft also carried greater freight and passenger loads, with more facilities and comfort for persons riding the empire routes, for instance, although American designers were promising bigger and still faster ships for use on domestic and foreign lines.
Night Flying.—Due to the facilities provided by the various Governments, night flying has become increasingly popular. Bea cons mark practically every important route in the United States and in Europe ; beam radio is in wide use in America, and radio telephone has been generally adopted. More than half of the commercial flying in the United States is done at night, and trans continental journeys of 2,50o and 3,00o miles from sunset to sunrise are common.
At the conclusion of the War when the whole world began to turn its attention to the possibilities of aviation as a commercial activity it was obvious that, if air transport was to accomplish even a small proportion of that which enthusiasts claimed for it, international regulations must be put into force as soon as possible, and the necessary steps were taken at the Peace Con ference in Paris during 1919.
International Convention.—The Treaty of Versailles brought into being an International Convention for the Regulation of Aerial Navigation, in which all the Allies participated; under the terms of this Convention a permanent Commission for Air Navigation was to be set up and placed under the direction of the League of Nations. In Great Britain, except for a brief period during Easter Week 1919, post-War civil aviation did not com mence officially until May 1, 1919. On Aug. 26, 1919, international civil flying from Great Britain was first started under temporary air navigation regulations.
By June 1922 the International Air Convention had been rati fied by a sufficient number of signatory states to make the intro duction of its regulations practicable. It was brought into force in Great Britain by the Air Navigation Order dated June 20, i922. Accordingly, the first meeting of the International Commission for Air Navigation was opened in Paris on July 11, 1922 (see AERIAL LAW). It has been evident that international air navi gation regulations were of vital importance, and during 1922, on ratification of the International Air Convention, to which reference has already been made, the International Commission for Air Navigation (known as the I.C.A.N. in England and as the C.I.N.A. on the continent of Europe) came into being. The following states are parties to the Convention and send repre sentatives to this Commission : Belgium, Great Britain and Northern Ireland, Canada, Australia, South Africa, New Zealand, Irish Free State, India, Bulgaria, Chile, France, Greece, Italy, Japan, Argentine Republic, Finland, Iraq, Norway, Netherlands, Spain, Switzerland, Yugoslavia, Poland, Portugal, Rumania, Siam, Czechoslovakia, Uruguay, Sweden, and Denmark.
The general principles laid down by the Convention are as follows: I. Innocent passage of commercial aircraft of the members over the territories of all.
2. Designation of customs aerodromes at suitable points at which aircraft must land.
3. Issue of licences to all members of the crew and airworthy certificates to all aircraft engaged in international commerce. The forms of these licences and certificates and the qualifica tions and tests to be demanded have been agreed upon by the Commission.
4. The establishment of a wireless and meteorological organi zation and a lighting system along air routes authorized by the nation over whose territory they lie.
The full Commission now meets twice every year, the place of meeting being decided on the invitation of one of the govern ments represented. The Commission has appointed standing sub commissions for the detailed study of operational, technical, medi cal and legal problems, and these meet at various dates between the meetings of the full Commission. Most European nations who are not members of the International Commission have drawn up regulations of their own, approximating those of the Inter national Commission, and many of them have entered into agree ments of various classes and duration with one another and with members of the International Commission in order to facilitate the operation of international air transport.
Since its creation the Commission has taken steps to modify Articles 5 and 34 of the Convention, which were unacceptable to certain ex-neutral and ex-enemy countries. These modifica tions came into force on Dec. 14, 1926, on the completion of ratification, and the way was opened for several other European nations to join the Convention. America, although a signatory to the Convention originally, has never deposited her ratification, but has established Federal legislation on the general lines of the Convention for the administration of inter-state air transport.
Each country through its national legislature gives effect to the International Air Convention and to the decisions of the International Commission. In Great Britain this is done by the Air Navigation Act, 192o, and by the air navigation orders and air navigation directions issued by the authorities from time to time thereunder.