FLYING ABOVE THE BOULDER DAM, on the Colorado River, this air liner is following the New York-San Francisco route of Transcontinental and Western Air, Incorporated. This route passes over some fine country, including the scenic Grand Canyon. The aeroplane is of the “skysleeper” type, which carries seventeen passengers and has eight sleeping compartments. The cabins are steam-heated and air-conditioned. Captain, first officer and stewardess make up the crew of three.
ONE of the major triumphs of civil aviation is the spanning of the United States by air from Atlantic to Pacific. The development of airports, of weather stations, of night flying and of swift and comfortable aircraft to serve the exacting routes between New York and California has given an impetus to flying in other continents. The Douglas Transport aeroplane, which was put into service in 1934, considerably reduced the time for the flight from New York to Los Angeles. The performance of this machine stimulated other manufacturers, and led to an acceleration of air transport in many parts of the world.
By 1938 the flight from New York to Los Angeles, against the prevailing winds, was scheduled to take seventeen hours, and the flight in the opposite direction fifteen hours ten minutes. In a period of about seven years the time of the flight of about 2,600 miles was reduced to one-third of what it had formerly been. Fares also were reduced to one-third: that is, to about £30, a slight additional charge being made for berths in the “sleeper planes”, and for the luxurious accommodation in some of the “day planes”.
Air mail pilots were the pioneers of the coast-to-coast route. They flew machines which had been built for the United States military forces. For years there were many of these machines and engines in use by the Post Office Department and by commercial companies. A route from New York to San Francisco by way of Cleveland, Chicago and Omaha was in operation in September 1920, but flying was possible only by daylight. The Post Office Department began the task of lighting the airway and installing radio facilities, erecting beacon lights and building intermediate landing fields. By July 1924 a through service from coast to coast was in operation night and day for mails. The Bureau of Air Commerce took over the establishment and maintenance of the airways in 1926. Then the contracts for the routes were given to commercial companies, and in 1927 mail and passengers began to be carried in commercial machines.
United Air Lines operate the New York-Chicago-California route, which was laid out by U.S. Government experts in 1919. The Boeing 40, a single-engined biplane, was designed for the Chicago-San Francisco section of the route. Twenty-four of these machines, the first specially built mail and passenger aircraft to be placed in service, began operating this section on July 1,1927. The machine weighed three tons and had a wing-span of 40 feet; its 425 horse-power engine enabled it to cruise at 105 miles an hour. The cruising range was three hours. There was a small compartment for two passengers between the mail compartments, and the pilot sat in an open cockpit. The engines were Wasps and, later, Hornets.
The journey from New York to San Francisco occupied about thirty-three hours, sometimes longer, and the machine landed fourteen times. The engine was not supercharged, and the aeroplane had to fly fairly low. As he lacked modern instruments, the pilot flew in sight of the ground.
Technical progress provided the pilot with radio, then with the directive radio beam, and soon afterwards with many other instruments. The three-engined Boeing 80-A, which seated fourteen passengers, was placed in service from 1930 to 1933, and machines of this type operated between Chicago and California by night as well as by day. Three-engined Ford aeroplanes carried passengers from New York to Chicago, where the passengers transferred to the Boeings. Later, the company launched a fleet of sixty Boeing 247s, fast twin-engined machines which, in 1933, cut off one-third of the coast-to-coast time and began a speeding up of air schedules that spread through the world. The metal twin-engined Boeings cut the time from thirty hours to twenty hours. In 1937 Douglas DC-3s were in service, reducing the time to about fifteen hours.
These liners are of three types - the “overnight sleeper”, the “skylounge mainliner” and the club type “main-liner”. The sleeper type has berths for fourteen passengers, the berths being converted into seats for day use. The skylounge type seats fourteen passengers in a saloon large enough for twenty-one seats. The swivel chairs are large, and the seats can be turned in any direction and can be adjusted to the reclining position if the passenger wishes to sleep. The club type machine seats twenty-one passengers in reclining chairs. The soundproofed cabin is 28 feet long, 8 feet wide and 6 ft 6-in high. The crew consists of the captain, the first officer and the stewardess.
U.S. Air Mail Route No. 1
This is the oldest air highway in the country, and is United States Air Mail Route No. 1. The company, United Air Lines, claims to have been the first to carry passengers from coast to coast, the first to fly passengers on long-distance night schedules, the first to develop two-way radio for aircraft, the first to establish technical and research laboratories, the first to fly modern high-speed multi-motored air liners, the first to offer stewardess service and the first to fly 100,000,000 miles. There are many other United Air Lines services in addition to the transcontinental service. Eleven round trips a day are scheduled between New York and Chicago, three between Chicago and San Francisco, two between Chicago and Salt Lake City, and one between Chicago and Omaha. There are six daily round trips between San Francisco and Los Angeles. Other round trips are Salt Lake City—Seattle; Pendleton—Spokane; San Diego—Seattle; Los Angeles—Seattle; Reno—San Francisco and Los Angeles—Portland.
After every period of 300 flying hours every machine must fly to the company’s repair base at Cheyenne, Wyoming, for a complete overhaul. The engines are removed, and the wings, propellers, rudder, instruments and undercarriage are dismantled. Every item is examined and tested. Then the aeroplane is reassembled and makes a test flight before being passed back into service.
THE PRINCIPAL AIR ROUTES OF THE UNITED STATES, and their connecting services. There are three trunk routes from the Atlantic coast to the Pacific coast, and each is operated by a different company. The T.W.A. route between New York and Los Angeles via Pittsburgh and St. Louis is claimed to be the shortest. It covers 2,557 miles.
Another coast-to-coast route is operated by American Airlines, Inc., with Douglas Transport aeroplanes which the company calls “flagships”. One, the American Mercury, flies between New York and Los Angeles with three stops, and another, the Southerner, with four stops. These aeroplanes are “sleepers”, carrying fourteen passengers. The compartment for the pilot and the first officer is forward; behind it is the compartment for 1,500 lb of mail and express goods. The engines are two 1,000 horse-power Wright Cyclones and drive three-bladed, constant speed, controllable-pitch propellers. The hubs of the propellers are equipped with a device which sprays a liquid on to them, and this prevents the formation of ice. Equipment fitted to the wings breaks off with a pulsating movement any ice that may form. The wing span is 95 feet and the overall length 65 feet. The gross weight of the machine when loaded is 24,000 lb. The fuel tanks in either wing hold a total of 822 American gallons (five-sixths of British gallons), giving a range of 2,000 miles. In addition to the “flagships”, American Airlines operate fourteen-passenger Douglas air-liners powered by two 725 horse-power Wright Cyclone engines.
A daily service is maintained between New York and Los Angeles by way of Washington, Nashville and Fort Worth, a distance of 2,649 miles. Another route is from Cleveland, Ohio, to Los Angeles by way of Nashville and Fort Worth (2,420 miles), the eastern coast link being provided by a daily service between Boston and Cleveland, a distance of 589 miles. The transcontinental route of American Airlines is the most southerly. Nashville (Tennessee) is the air junction where passengers from cities lying north and east arrive by air to join the transcontinental aeroplane. Other services of the company bring passengers from Detroit, Chicago, St. Louis and Tulsa (Oklahoma) to Dallas (Texas), another junction on the coast-to-coast route. From Tulsa there is an alternative route through Oklahoma City, joining the coast-to-coast airway at Fort Worth.
Surveyed by Col. Lindbergh
Westward from Fort Worth the flagships fly to El Paso, New Mexico, on the border of Mexico, whence connecting aeroplanes fly to Mexico. The direct route from Fort Worth to El Paso is 534 miles, and the direct route from El Paso to Los Angeles is 746 miles. Alternative routes afford stops at Douglas, Tucson and Phoenix, in Arizona, and Palm Springs, in California.
Two coast-to-coast routes are operated by Transcontinental and Western Air, Inc., commonly known as TWA. Colonel Charles A. Lindbergh surveyed the first TWA route after his Atlantic flight. The Post Office Department had suggested that three coast-to-coast trunk routes should be operated, each by a different company, and Transcontinental and Western Air was formed to operate the middle route, the routes of United Air Lines and American Airlines being north and south of it on the western section.
The TWA route between New York and Los Angeles runs through Pittsburgh, St. Louis, Kansas City, and Albuquerque, and is the shortest, 2,557 miles. Another New York-Los Angeles route of 2,583 miles is through Chicago and Kansas City. TWA also operates a coast-to-coast route between New York and San Francisco by way of Chicago, Kansas City and Albuquerque.
When the company began operating, the passengers were at first carried by day only. With the experience gained by flying mails at night the company was later able to arrange a twenty-four-hours passenger service operating by night and by day. This was a step forward, but the directors, all of them experienced pilots, realized that the machines were too slow, noisy and uncomfortable for satisfactory passenger service.
PASSENGERS ALIGHTING from a T.W.A. “skysleeper” on completion of a coast-to-coast flight. The scheduled time is 15 hours 10 minutes eastbound, and 17 hours westbound. The difference in times is accounted for by the direction of the prevalent winds. The machine when fully loaded can travel at a speed of about 216 miles an hour. Each engine develops 1,220 horse-power, and the aircraft can be maintained in level flight at 10,500 feet on one engine. A “skysleeper ” has a lounge cabin, as well as sleeping berths.
They collected ideas from every branch of the service and evolved the specification for the type of machine that would attract passengers to their route. The Douglas Aircraft Company produced a machine which exceeded in performance almost every requirement of the company. The first Douglas commercial air liner was built in July 1933. More than thirty Douglas machines were ordered by TWA and were placed in service in the spring of 1934, reducing the coast-to-coast time to sixteen hours. Faster Douglas machines were put into service in 1937, reducing the time to about fifteen hours.
The TWA aeroplanes are of three types, “skysleepers”, “skyclubs” and “skyliners”. The total horse-power of the two Wright Cyclone motors on the “skysleepers” and “skyclubs” is 2,440 and gives a maximum speed of about 216 miles an hour and a cruising speed of 185 miles an hour.
With one motor the aircraft can maintain an altitude of 10,500 feet. The “skysleeper” carries seventeen passengers. There are sleeping compartments for eight and in the lounge cabin are nine divan chairs with adjustable backs. The lounge cabin is separated from the sleeping compartments. The “skyclubs” seat seventeen passengers in a space licensed for twenty-five. The cabins are steam-heated and air-conditioned. The “skyliners” are smaller machines powered by two 700 horse-power motors. They carry fourteen passengers. All the aeroplanes carry a crew of three, captain, first officer and “hostess” (stewardess).
Boeing four-engined aeroplanes of 42,000 lb gross weight were put into service in 1938, with berths for eighteen passengers and accommodation for thirty-two. Four-engined Douglas machines to seat forty passengers were being built early in 1938. The TWA company is also carrying out high-altitude research with a monoplane equipped as a laboratory. This machine can maintain full rated horsepower at 30,000 feet. The results of the experiments are to be applied to new aircraft, as the aim is to raise the atmospheric pressure in the pilot’s and passenger compartments so that the aircraft can operate at 30,000 feet and thus fly above storms and turbulent air.
PREPARING A HOT MEAL while the air liner is in flight. This is one of the tasks of the “hostess” or stewardess, who looks after the comfort of the passengers. Luxury is a feature of the main air routes in the United States, and the air liners are fitted for fewer passengers than could be accommodated, to give more room to everybody in them.
Extensive training is required of the personnel who fly the machines and operate and maintain the airways. To obtain the Air Transport Rating of the Bureau of Air Commerce, a pilot must have at least 1,200 hours’ solo flying and be qualified to fly by instruments when conditions are adverse. The TWA company insists on a minimum of 2,000 hours’ flying before it employs a pilot. The pilot is constantly re-examined and schooled by instructors in instrument flying. Every three months the pilot’s flying ability and physical condition are checked.
In this examination the pilot is placed in a “hooded” cockpit. The pilot, accompanied by the examining officer, takes off and flies under the examiner’s instructions, the examiner checking every manoeuvre. Later the examiner takes the controls and does everything he can to disconcert and “lose” the pilot. Perhaps, during a climbing turn, the examiner hands over to the pilot. The pilot has to put the aeroplane into the normal flying position, determine his position and proceed to the airport, flying entirely by instruments.
The pilots frequently change runs so that they can become familiar with all divisions. They attend the schools conducted by the company and receive instruction in navigation, meteorology, radio and maintenance, in addition to the technique of flying. All the Government-licensed flight dispatchers are experienced pilots who are familiar with the routes. These men maintain day and night supervision over the movements of the aircraft. They frequently make trips to keep in touch with conditions.
An hour before an aeroplane is due to leave, the captain and first officer confer with the meteorologist and the flight dispatcher and lay out a flight plan for the trip. The flight plan contains every detail of the flight and also the alternative procedure to be followed if the unexpected should occur. Nothing is left to chance. The pilot enters on his plan his estimated time over various check points, the altitude at which he expects to fly, the percentage of power to be used, the estimated consumption of petrol, the compass course for each leg of the flight, the climbing time, the cruising time and the elapsed time. He also states where he will land in the event of unexpected storms or failure of any part of his equipment. Sufficient fuel is carried to reach the alternative airports and to fly for forty-five minutes beyond them.
(Top)AN AMERICAN AIRLINES “FLAGSHIP”. This picture shows one of the Douglas aeroplanes used by American Airlines Incorporated. It has two Wright Cyclone engines which drive controllable-pitch propellers. The propeller hubs and the wings are provided with devices for dealing with the possibility of ice formation in cold weather.
(Bottom) IN THE CONTROL OFFICE. This picture shows the T.W.A. “dispatcher” at Kansas City Missouri, speaking into the microphone. Flight dispatchers are Government-licensed men and are experienced pilots; they maintain day and night supervision over the movements of aircraft. These men frequently make trips over the routes to keep in touch with the prevailing conditions.
During the flight the pilot reports to the ground radio operator the time he passes the check points. He can use his two-way radio to communicate with the ground at any time, and the flight dispatcher can communicate with him and give him information. A flight log is kept of the performance of the engines, and of the altitudes, speed and weather; these logs are analysed and studied to aid in improving the service.
Flights are permitted only when the conditions are better than the limits of safety set by the Bureau of Air Commerce, and all flights are released subject to the pilot’s discretion. The pilot undertakes the flight only if he considers that the trip can be completed safely. He is not pressed to make a flight, neither is he allowed to press the flight dispatcher to release the flight. Should bad weather arise unexpectedly either the dispatcher or the pilot may postpone or cancel the flight.
To avoid the danger of collision, east-bound aeroplanes fly at odd thousand feet altitudes, and westbound aeroplanes at even thousand feet altitudes. Pilots of aeroplanes flying in opposite directions communicate with one another while approaching in the same section.
“Air Mass” Analysis
At the large airports the operations are controlled locally by officers of the Federal Airway Control and by control tower officers. Machines in the vicinity of an airport receive by radio the instructions of the control tower officer concerned.
The meteorologists are trained in the Norwegian “air mass” analysis system. Movements of masses of air are studied and analysed to predict conditions along the airway from coast to coast. Meteorologists are stationed at Los Angelos, Kansas City and New York, and they work in shifts to cover the twenty-four hours. Areas of low pressure indicate stormy conditions. The “fronts” are the dividing lines between high- and low-pressure masses of air. The storms over the route generally move from north-west to south-east and east. A Bureau of Air Commerce teletypewriter in the office of each meteorologist types weather reports from North America and from ships at sea. From this information the meteorologists every six hours prepare maps showing the changes, and they then issue forecasts covering eight hours, the overlapping period being to ensure greater accuracy. If the weather is changing quickly special forecasts are issued hourly.
The chief meteorologist at Kansas City receives all reports. Twice daily an advisory report about the operation of aeroplanes is sent to all stations. Each meteorologist goes to Kansas City every three months for additional technical training. He is required also to make frequent flights to keep himself familiar with the route for which he forecasts the weather. As a further check, the pilots report on each weather forecast so that the weather experienced can be compared with its forecast.
A “MAINLINER” OF UNITED AIR LINES. This machine has Pratt and Whitney Wasp engines, each capable of developing 1,150 horse-power. Using only 62 per cent of its power, the aircraft can cruise at 190 miles an hour. It can also climb nearly two miles high on one engine. The wheels retract upwards into the wings behind the engines when the aircraft is in flight. With a cruising range of 1,500 miles, these machines are able to make the coast-to-coast trip with only three stops.
There are three separate radio receivers in each aeroplane. The two-way radio telephone is for communicating with the company’s ground stations or with the Bureau of Air Commerce stations. The receiver and transmitter operate on four frequencies, two by day and two by night. The second receiver is for the beam signals and weather reports which are sent from Bureau of Air Commerce stations, and also for the localizer beams used at certain of the airports. The third receiver is the auxiliary standby unit, which has two wavelength bands. One band receives beam signals, weather reports and localizer beams; the other band receives the range of night frequencies on which all air lines broadcast.
There are four radio aerial or antenna systems: the loop, the belly antenna beneath the fuselage, the antenna which trails from the tail, and the fin antenna placed diagonally between the top of the vertical fin and the upper surface of the fuselage. The loop is for receiving signals and as a navigational aid, the belly or loop for the standby receiver, the trailer for the two-way telephone, and the fin for the beam and weather.
The instruments in the pilot’s compartment include instruments to record air speed, engine speed, compass course, oil temperature and so forth. The automatic gyro pilot relieves the human pilot of routine flying and enables him to devote time to navigation.
At the end of every trip the engines and operating parts of the aeroplane are examined and adjusted when necessary. After every sixty hours a more exhaustive inspection is given, and after 500 hours the machine goes to the Kansas City “round house”, where the engines are removed for a complete overhaul.
Lavish Ground Equipment
Each motor is taken down and the parts are immersed in a solution which cleans them, some parts being further cleaned by sandblasting. After thorough renovation and inspection the motors are reassembled, tested and then reinstalled for the test flight. Landing wheels, brakes and tail wheels are removed after 200 hours. After 2,000 hours wings, rudder, elevators and ailerons are removed and renovated.
The air highways of the United States comprise commercial and municipal airports, the intermediate landing fields of the Bureau of Air Commerce, military and State-owned airports, beam signals, beacons and weather stations. At no time during a flight is an aeroplane on the coast-to-coast route more than nine minutes from a suitable landing site. In addition to the main airports there are more than 250 lighted intermediate fields and 580 marked auxiliary fields. The more important intermediate ports are in the charge of caretakers who look after the equipment provided by the Government, and all ports have supplies of fuel. Radio beams and broadcasting stations are located at 100-miles intervals along the airways. At night rotating or flashing beacons light the airways and the pilot can identify each beacon by timing the flashes.
Another necessary work has been the establishment of marks on roofs, on roads or on the ground to guide private pilots of machines not equipped with radio. It was decided to have 16,000 such marks and most of these were completed by 1938.
The remarkable growth in commercial aviation in the United States is partly due to the far-sighted action of the Federal Government which, in 1933, put thousands of unemployed to work at building and improving the airports. Newark Airport, New Jersey, is said to be the busiest air traffic centre in existence. It has recently been improved, as has Cleveland Airport, one of the largest commercial airports in the world.
PASSENGERS BOARDING AN AIRLINER AT NEWARK AIRPORT, New Jersey, which is said to be the busiest air traffic centre in the world. This aerodrome has recently been considerably enlarged and improved. It is the point of departure for air liners from New York to cities throughout the United States, and is used by the three companies operating coast-to-coast routes.