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U.S. Army transfers mail to Post Office

The U.S. Army transfers responsibility for airmail delivery to the Post Office Department in August 1918, which launches the first regular air mail service between College Park, Maryland, and Chicago.

Curtiss JN-4H Jenny

A Curtiss-Jenny at the Omaha air mail station in 1918.

Boeing and Hubbard fly international airmail

On March 3, 1919, William Boeing (right) and pilot Eddie Hubbard performed the first U.S. international airmail flight in this Boeing Model C. They flew from Vancouver, British Columbia, Canada, to Seattle, Washington.

Standard mail plane

A Standard mail plane during the first year of airmail service, 1918.

De Havilland mail plane

The de Havilland of World War I was converted in 1920 to fly U.S. airmail routes. This plane flew on the Chicago-Omaha route.

De Havilland 4B flying mail

A de Havilland 4B wings its way coast to coast bearing 350 pounds of mail. Wingtip lights were added to U.S. Army Air Service planes once cross-country routes were established on a regular basis.

J.L.6 mail plane

American businessman John Larsen imported the Junkers F 13 transport plane and sold it in the United States as the J.L. 6. The U.S. Air Mail Service bought eight Junkers for use between New York, Chicago, and Omaha. The Service thought that because the plane was all metal, it would be safe from fire, but they were mistaken.

Original transcontinental route

The transcontinental airmail route ran from New York to San Francisco opened August 20, 1920. Intermediate stops were at Bellefonte, Pennsylvania; Cleveland, Ohio; Bryan, Ohio; Chicago, Illinois; Iowa City, Iowa' Omaha, Nebraska' North Platte, Nebraska; Cheyenne, Wyoming; Rawlins, Wyoming; Rock Springs, Wyoming; Salt Lake City, Utah; Elko, Nevada; and Reno, Nevada.

DH-4B in Omaha

By the time this photo was taken at the Omaha, Nebraska airmail field in 1921, Elmer G. Leonhardt's DH-4B airplane had force-landed four times. One incident occurred on the first day of the first day-night transcontinental flight.

Night-flying beacon

Night-flying beacons of this type were placed along the route between Chicago and Cheyenne, Wyoming, to guide airmail pilots. These miniature "lighthouses" were placed three miles apart. Each was visible for 10 miles, forming a continuous path across the dark ground below.

Test of light system in 1923

The first transcontinental flight to fly over night arrives at Curtiss Field, New York, August 22, 1923. This tested the lighted airway.

The Post Office Flies the Mail, 1918-1924

On August 12, 1918, the Post Office Department took over airmail service from the U.S. Army Air Service (USAAS). Assistant Postmaster General Otto Praeger appointed Benjamin B. Lipsner, who left the USAAS, to head the civilian-operated Air Mail Service. He would remain only until December 6, when he resigned over what he felt were wasteful and “unnecessary expenditures.” One of Lipsner's first acts was to hire four pilots, each with at least 1,000 hours flying experience, paying them an average of $4,000 per year. The department also abandoned the polo grounds in Washington, D.C., and moved north to the larger airfield at College Park, Maryland, where it would begin its route to Philadelphia.


The department used mostly World War I surplus de Havilland DH-4 aircraft, which were flimsy and not designed for long cross-country flights. Another popular plane was the Standard Aircraft Company JR-1B, which could carry 300 pounds (136 kilograms) of mail as well as 60 gallons (227 liters) of fuel. During 1918, including the initial four pilots, the Post Office hired 40 pilots, and by 1920, they had delivered 49 million letters. In its first year of operation, the Post Office completed 1,208 airmail flights with 90 forced landings. Of those, 53 were due to weather and 37 to engine failure. The Post Office also bought the German-made Junkers F 13, which it renamed the J.L.6 after John Larsen, who had imported it to the United States. The postal service had high hopes for this all-metal plane, but it proved extremely dangerous and was removed from service after several pilots were killed in fiery crashes.


Postal aircraft could fly with sacks of mail for an average cost of $64.80 for each hour in the air. Pilots received a base pay of about $3,600 per year and then were paid five to seven cents more for each mile they flew, flying an average of five to six hours each day. After a year in operation, postal revenues for the year totaled $162,000. The cost to fly the mail had been just $143,000. This first year of operation was to be the only time in airmail history that the service showed a profit.


The largest airmail customers were in the banking business. They used the service to send checks and financial papers more quickly. Bankers wanted to reduce the float time of checks and pushed for an extension of routes. Financial papers were light, and the cost to send them was low—just 16 cents an ounce, having been reduced from 24 cents in July 1918 to attract more customers. It was further reduced to six cents per ounce on December 15, in an effort to draw even more customers. In July 1919, the extra charge for airmail was eliminated completely and airplanes began to carry a random selection of mail. The charge would be reinstated in 1924 when regular transcontinental service began.


International airmail delivery began on March 3, 1919, when Bill Boeing and Eddie Hubbard carried 60 letters from Vancouver, Canada, to Seattle, Washington, in a Boeing Model C. Later that year, Hubbard began flying a Boeing B-1 flying boat for airmail delivery between Seattle and Victoria, British Columbia. He would continue flying the plane for eight years—amassing more than 350,000 miles (563,270 kilometers).


Flying conditions were poor, and the pilots were forced to fly in all kinds of weather. Praeger, who didn't know how to fly, was unyielding about keeping the mail on schedule in spite of the risk, hoping that it would make the public trust the service more. Tragically, of the 40 pilots hired when the Post Office took over airmail operations, at least half had died by 1920, most from weather-related crashes.


In July 1919, pilot Leon Smith refused to fly the mail from New York to Washington, D.C., because of rain, clouds, and visibility of only 200 feet (61 meters). Praeger ordered him to make the trip anyway, using only his magnetic compass to navigate. Smith and his fellow pilot E. Hamilton “Ham” Lee refused to fly in the dangerous weather. Both pilots were fired and then, all the pilots in the airmail system went on strike. After three days of talks, the pilots and managers agreed to require field managers to make a flight check in bad weather. The field managers could either fly the inspection themselves or if they were not pilots, could sit in the mail bin in front of the pilot. The flight would continue only if the field manager said weather conditions were safe for flying.


Postal planes began flying across the country on September 8, 1920. But these flights took place only in daylight because pilots relied on visual landmarks to navigate. Each night, the mail would be loaded onto railcars and would travel overnight until daylight allowed another plane to take over. Rugged terrain and poor weather, especially in the West, combined with unreliable planes to slow the service. The service was criticized for being uneconomical and unsafe. Praeger decided to demonstrate how far airmail had come by flying across the country by day and by night. On February 22, 1921, pilot Jack Knight helped to change the mix of railroads and aircraft and give airmail service more status during a test of transcontinental airmail.


As part of a relay team of pilots from San Francisco to New York, Knight was scheduled to carry the mail only part of the way, but a snowstorm in Chicago delayed all the other pilots. Knight flew the mail from North Platte, Nebraska, all the way to Chicago, though normally other pilots waiting at stations would have split the trip. Much of Knight's flying was by night in the bitter cold. He found his way by looking for bonfires and flares lit by helpers on the ground. After 830 miles (1328 kilometers), Knight finally connected with his relief pilot in Chicago. When the last man in the relay reached New York, the total time to carry the mail had been 33 hours 20 minutes—compared to four and a half days by train. This was Praeger's final triumph before he was replaced in April when the administration changed.


Progress continued to be made. By November 1921, 10 radio stations were installed along the New York-San Francisco routes to transmit weather forecasts. Soon, parachute flares were installed in the undercarriage of aircraft to light emergency fields. Flashing beacon lamps or searchlights were mounted on towers all across the United States 10 to 30 miles (16 to 48 kilometers) apart depending on the terrain. Most pilots still flew about 200 to 500 feet (60 to 152 meters) above ground level so they could navigate by roads and railways. By the end of 1921, 98 airmail planes were in service. In 1922, Tex Marshall helped form the Air Mail Pilots Association and became its president. On July 16, 1922, the Air Mail Service could brag that it had completed one year of flying without a fatal accident. In February 1923, the service was awarded the Collier Trophy for its achievements.


Regularly scheduled transcontinental service began on July 1, 1924, using pilots leaving from both the East and West coasts. The pilots also began regular night flights. They were guided by a lighted transcontinental airway with rotating beacons and brightly lit emergency landing fields along the way, and they timed their night flying so as to reach the end of the lighted airway by daybreak. They tested the new gyroscopic needle to indicate whether aircraft wings were level and altimeters to show if the aircraft was climbing or descending. The Post Office resumed using special airmail postage, which it had discontinued in 1919. Airmail now cost eight cents to travel in any of the three zones comprising the transcontinental route and could travel all across the country for 24 cents. By the end of 1924, airmail planes were routinely completing the New York to San Francisco route within 34 hours.




Bruns, James H. Mail on the Move. Polo, Illinois: Transportation Trails, 1992.

___________. Turk Bird--The High-Flying Life and Times of Eddie Gardner. National Postal Museum, Washington, D.C.: Smithsonian Institution Press, 1998.

Chaikin, Andrew. Air and Space--The National Air and Space Museum Story of Flight. Boston: Bulfinch Press/Little, Brown and Company, 1997.

Christy, Joe, Wells, Alexander T. American Aviation--An Illustrated History. Blue Ridge Summit, Pa.: Tab Books Inc., 1987.

Ethell, Jeffrey L. Smithsonian Frontiers of Flight. Washington, D.C.: Smithsonian Books, New York: Orion Books, 1992.

Jackson, Donald Dale. Flying the Mail. Alexandria, Va.: Time-Life Books, 1982.

Leary, William M. Aerial Pioneers – The U.S. Air Mail Service, 1918-1927. Washington, D.C.: Smithsonian Institution Press, 1985.

Smith, Henry Ladd. Airways: The History of Commercial Aviation in the United States. New York: Russell & Russell, Inc. 1965.


Further Reading:

Boughner, Fred. Airmail Antics. Sidney, Ohio: Amos Press Inc., 1988.

Heppenheimer, T.A. Turbulent Skies; The History of Commercial Aviation. New York: John Wiley & Sons, 1995.

Holmes, Donald B. Airmail, An illustrated History 1793-1981. New York: Clarkson N. Potter Inc., 1981.

Lipsner, Benjamin B. The Airmail Jennies to Jets. As told to Leonard Finley Hiltsd. Chicago: Illinois, Wilcox and Follett Company, 1951.

Shamburger, Page. Tracks Across the Sky. New York: J.B. Lippincott Company, 1964.


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