Loening OA-1A San Francisco

The historic Pan-American Goodwill Flight of 1926 and 1927 through Mexico and Central and South America was intended to improve relations with Latin American countries, to encourage commercial aviation, and to provide valuable training for Air Corps personnel. The flight was made by ten pilots in five Loening OA-1A amphibian aircraft. To stimulate public interest, each airplane was named after a major U.S. city-the New York, the San Antonio, the San Francisco, the Detroit, and the St. Louis.

The 35,200 km (22,000 mi) flight began on December 21, 1926, from San Antonio, Texas. The journey took 59 flying days, interspersed with 74 days for scheduled maintenance and diplomatic meetings and ceremonies. The flight concluded at Bolling Field in Washington, D.C., on May 2, 1927. Within three weeks, however, the impressive achievement was eclipsed by Lindbergh's solo trans-Atlantic flight in the Spirit of St. Louis.

The Loening OA-1A, San Francisco, in the NASM collection participated in the historic Pan-American Goodwill Flight of 1926 and 1927. The project was proposed by Maj. Gen. Mason Patrick, chief of army aviation. He suggested a flight through Mexico and Central and South America to improve relations with Latin American countries, to encourage commercial aviation, and to provide valuable training for army personnel. (Patrick had planned the successful round-the-world flight of the Douglas World Cruisers in 1924.) The idea was enthusiastically endorsed by the Secretary of War, Dwight Davis, and the Secretary of State, Frank B. Kellogg. Supporters of the flight hoped also that the mission would interest the Latin American nations in U.S. aircraft and engines, emphasize the advantages of aviation for transportation and communications in regions that were without rail or road transport, and to help stimulate the struggling U.S. aircraft industry.

The flight was made by ten pilots in five aircraft. The airplane type selected for the mis-sion was the Loening OA-1A amphib-ian, a design by Grover Loening that had recently been submitted to the army for evaluation as a new observation aircraft. The hull was constructed of duralumin over a wooden frame, and the fuselage was built on top of the hull. The OA-lA was powered by a 420-horsepower, water-cooled Liberty V-12 engine that was mounted inverted. This orientation of the engine was necessary for the propeller to clear the forward end of the hull. However, mounting the engine upside down created maintenance problems. Unless the piston rings were perfectly fitted, oil leaked past them, fouling the spark plugs. It was normal at each stop to remove the twenty-four plugs and clean and replace them before starting the next leg of the journey.

Another time-consuming and laborious task was refueling. Gasoline in steel drums was stored along the route. It had to be hand-pumped through a chamois-covered funnel into the fuel tanks. At a normal rate of sixty gallons per hour, it took more than three hours to fill the Loening's full capacity of 757 liters (200 gallons).

The weight of the each airplane, fully loaded, including all the supplies and baggage carried on the Pan American Flight, was nearly three tons. In spite of the weight, flying character-istics of the OA-1A were very good. An average cruising speed of 136 kph (85 mph) to 144kph (90 mph) was maintained during the Goodwill Flight. The utility of the aircraft and their design and construction details were thoroughly tested, and proved to be excellent. The versatile airplanes were able to make forced landings that would have been impossible for other types of aircraft.

To stimulate public interest, each of the five airplanes was named after a major U.S. city. They were the New York, the San Antonio, the San Francisco, the Detroit, and the St. Louis. Crew members on the Goodwill Flight were:

The New York-Major Herbert A. Dargue, pilot and commander of the flight; First Lieutenant Ennis Whitehead, copilot.

The San Antonio-Captain A.B. McDaniel, pilot; First Lieutenant Charles McK. Robinson, copilot.

The San Francisco-Captain Ira C. Eaker, pilot; First Lieutenant Muir S. Fairchild, copilot.

The Detroit-Captain C.F. Woolsey, pilot; First Lieutenant John W. Benton, copilot.

The St. Louis-First Lieutenant Bernard S. Thompson, pilot; First Lieutenant L. D. Weddington, copilot.

Advance officers visited all the planned stops, selected landing areas, arranged the diplomatic schedule, and selected representatives who were contracted to store the advance ship-ments of engines, spare parts, and other supplies. The flight schedule included fifty-six flying days and seventy-seven de-lay days for maintenance and diplomatic meetings and ceremonies-a total of 133 days. As actually exe-cuted, the journey took 59 flying days and 74 delay days, and was thus completed ex-actly on schedule.

The 35,200 km (22,000 mi) flight began on December 21, 1926, from San Antonio, Texas. The course extended through Mexico, Guatemala, El Salvador, Honduras, Nicaragua, and Costa Rica; across the Panama Canal to Colombia, Ecuador, Peru and Bolivia; down the west coast of South America to Valdivia, Chile; across the Andes Mountains to Bahia Blanca, Argentina; north to Montevideo, Uruguay; up to Paraguay; back down the Paraná River; along the coasts of Argentina, Uruguay, Brazil, the Guianas, and Venezuela; thence through the West Indies and up the coast of the United States to Washington, D.C.

Diplomatic functions required that the airplanes remain a day or two at each of twenty-five capital cities on the route. In addition to participating in the ceremonial functions, the pilots also carried out all the maintenance work on the airplanes themselves, as there were no qualified aircraft maintenance technicians along the route. The stops had been carefully selected and spare parts were cached at strategic locations. At many of these places the local residents saw an airplane for the first time. Weather forecasting en route was very unreliable because no advance weather information facilities existed. To add to their difficulties, the pilots could communicate in flight only by hand signals.

One accident marred the tour. As the Detroit and the New York were approaching for a landing at the Argentine Air Service Field at Palomar, Buenos Aires, they collided in mid-air, killing the crew of the Detroit, and destroying both airplanes.

The flight concluded at Bolling Field in Washington, D.C., on May 2, 1927. The fliers were greeted by President Calvin Coolidge and other dignitaries. Within three weeks, however, the historic flight was eclipsed in the public eye by the solo trans-Atlantic flight of Charles A. Lindbergh in the Spirit of St. Louis.

The participants in the two historic flights were also linked in another way. After his official welcome in Washington, Lindbergh flew to New York City for ceremonies on June 13, 1927. He landed at Mitchel Field, Long Island. There the Loening amphibian San Francisco awaited him, with Captain Ira C. Eaker as pilot. Utilizing the aircraft's unique ability to take off from land and alight in the water, Lindbergh was flown to a landing in New York harbor where he boarded a ship that took him to lower Manhattan for his triumphal entry into the city.

One of the long-term legacies of the Pan American Goodwill Fight was that it helped pioneer a trail for later commercial air transport operations. When Pan American Airways began South American air service about two years later, the company selected its stations in a pattern closely following the route of the Goodwill Flight.

The San Francisco was transferred to the Smithsonian Institution by the War Department in December 1927. It was restored by the National Air and Space Museum in 1964-1965.