The personnel and the ground facilities that have produced such excellent results in the Air Mail Service are discussed apart from the flying equipment and its operation in the air. An airway is on the ground and the performance and safety of the pilots are dependent upon the ground facilities provided and the efficiency of the ground personnel. Pilots perform a highly important part in the operation of airlines and no matter how good the flying equipment may be, the desired results cannot be obtained without thoroughly trained and capable pilots. When selecting new pilots, the Air Mail Service looks for men who handle an airplane in a businesslike way and who are able, without taking unnecessary risks, to fly the ship without letting the ship fly them. Desired qualifications are that an applicant should have had 400 hr. in the air, of which 200 hr. shall have been behind a Liberty engine or one of equal size; have learned to fly before he was 25 years of age; have a knowledge of navigation; be able to fly a given course cross-country; and be in good physical condition and especially have good eyesight. The Air Mail Service believes that it has the best group of pilots in the world. For a period of 2 years it did not take on, discharge or lose a pilot. An ample supply of pilots is available for the next 5 years at least, as 10,000 pilots were trained during the late war.
Maintenance of the flying equipment is the most important and most difficult part of the work. Morale of the pilots can very easily be ruined by giving them airplanes to fly which are not in good condition. A thoroughly organized force of trained mechanics, working under careful supervision, is needed. A typical terminal-field organization consists of 13 men reporting directly to the field manager and 18 reporting to the field manager through the chief mechanic. The organization includes chief mechanics and crew chiefs, engine and airplane mechanics, field and stock clerks, radio operators, a chauffeur, an automobile mechanic, riggers and mechanics, helpers, electricians, an instrument man and a parachute maintenance man.
The system of inspection after every trip and of reporting on the condition of the engine and airplane is described in detail. The inspections are checked and double-checked before being O. K'd by the chief mechanic and the airplane turned over again to a pilot. Engines are overhauled after every 100 hr. of flying and after five or six overhauls are torn down and about 30 per cent of the parts-value is salvaged, the usable parts being used in building-up other engines. Mechanical difficulties cause forced landings once in each 400 hr. of flying. Thirty per cent of the troubles are with the cooling system, 29 per cent with ignition, 11 per cent with carburetion and 8 per cent with lubrication. The airplanes average about 800 hr. of flying before they are given a major overhaul and rebuilding. The fabric covering is renewed after about 500 hr. Only one airplane failure has occurred in the last 5 years.
Terminal, semi-terminal and emergency landing-fields and their equipment are described. Reports of weather conditions and of arrivals and departures of airplanes are transmitted by radio except when static interferes and then the long-distance telephone is used. It may be that some day the Air Mail Service will have its own telephone or telegraph lines along its airways, as the railroads do, and the same pole-lines may carry current for the beacon lights. It has been said that the Air Mail has the best-lighted airway in the world, but it has been lighted only a little more than 1 year and the officials can see wherein great improvements are possible. An airway can be so prepared and lighted as positively to insure as safe and regular operation as exists in any method of transportation and at a cost of only about 10 per cent of the cost of building a single-track railroad.