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The Boeing 314 (known erroneously as the Clipper, after the name given by Pan American World Airways) was a long-range flying boat produced by the Boeing Airplane Company between 1938 and 1941 and is comparable to the British Short Empire. One of the largest aircraft of the time, it used the massive wing of Boeing’s earlier XB-15 bomber prototype to achieve the range necessary for flights across the Atlantic and Pacific Oceans. Twelve Clippers were built for PanAm, three of which were sold to BOAC in 1941 before delivery.

Design and development[]

The 314 was a response to Pan American's request for a flying boat with unprecedented range capability that could augment the airline's trans-Pacific Martin M-130. Boeing's bid was successful and Pan American signed a contract for six aircraft on 21 July 1936. Boeing engineers adapted the cancelled XB-15's 149 foot (45.5 m) wing, and replaced the original 850 hp (640 kW) Pratt & Whitney Twin Wasp radial engines with the more powerful 1,600 hp (1,194 kW) Wright Twin Cyclone. The Clipper's triple tail was chosen after Boeing tested conventional and twin tails which did not provide enough controllability for safe flight.

Internally, the 314 used a series of heavy ribs and spars to create a robust fuselage and cantilevered wing. This sturdy structure negated the need for external drag-inducing struts to brace the wings, something other flying boats of the day could not boast. Boeing addressed the flying boats' other drag-inducing issue, stabilizing pontoons, by incorporating sponsons into the hull structure. The sponsons, which were broad lateral extensions placed at the water line, on both the port and starboard sides of the hull, served several purposes: they provided a wide platform to stabilize the craft while floating on water, they acted as an entryway for passengers boarding the aircraft and they were shaped to contribute lift while the aircraft was in flight. To fly the long ranges needed for trans-Pacific service, the 314 carried 4,246 US gallons (19,300 L) of gasoline. The later 314A model carried a further 1,200 US gallons (4,540 L). To quench the radial engines’ thirst for oil, a capacity of 300 US gallons (1,135 L) was required.

Pan Am's "Clippers" were built for luxury, a necessity given the long duration of transoceanic flights. The seats could be converted into 36 bunks for overnight accommodation; with a cruise speed of only 188 mph (300 km/h), many flights lasted over twelve hours. The aircraft had a lounge and dining area, and the galleys were crewed by chefs from four-star hotels. Men and women were provided with separate dressing rooms, and white-coated stewards served five and six-course meals with gleaming silver service. Although the transatlantic flights were only operated for three months in 1939, their standard of luxury has not been matched by heavier-than-air transport since then; they were a form of travel for the super-rich, at $675 return from New York to Southampton, comparable to a round trip aboard Concorde in 2006.[1]

Equally critical to the 314's success was the proficiency of its Pan Am flight crews, who were extremely skilled at long-distance, over-water flight operations and navigation. Only very best and most experienced flight crews were assigned Boeing 314 flying boat duty. Before coming aboard, all Pan Am captains as well as first and second officers had thousands of hours of flight time in other seaplanes and flying boats. Rigorous training in dead reckoning, timed turns, judging drift from sea current, astral navigation, and radio navigation were conducted. In conditions of poor or no visibility, pilots sometimes made successful landings at fogged-in harbors by landing out to sea, then taxiing the plane into port.[2]

Operational history[]

File:FAM 18 Round the World 1939.jpg

Flown cover carried around the world on PAA Boeing 314 Clippers and Imperial Airways Short S23 flying boats 24 June–28 July 1939 (The Cooper Collections)

The first 314, Honolulu Clipper, entered regular service on the San Francisco-Hong Kong route in January 1939. A one-way trip on this route took over six days to complete. Commercial passenger service lasted less than three years, ending when the United States entered World War II in December 1941.

At the outbreak of the war in the Pacific, the Pacific Clipper was enroute to New Zealand. Rather than risk flying back to Honolulu and being shot down by Japanese aircraft, it was decided to fly west to New York. Starting on December 8 1941 at Auckland, New Zealand, the Pacific Clipper covered over 8,500 miles via such exotic locales as Surabaya, Karachi, Bahrain, Khartoum and Leopoldville. The Pacific Clipper landed at Pan American's LaGuardia Field seaplane base at 7:12 on the morning of 6 January 1942.

The Yankee Clipper flew across the Atlantic on a route from Southamption to New York with intermediate stops at Foynes, Ireland, Botwood, Newfoundland, and Shediac, New Brunswick. The inaugural trip occurred on 24 June 1939.

The Clipper fleet was pressed into military service during World War II, and the aircraft were used for ferrying personnel and equipment to the European and Pacific fronts. In actual fact, only the markings on the planes changed: the Clippers continued to be flown by their experienced Pan Am civilian crews. American military cargo was carried via Natal, Brazil to Liberia, to supply the British forces at Cairo and even the Russians, via Teheran. The Clipper was the only aircraft in the world that could make the 2,150 statute-mile crossing over water.[3] These shuttle aircraft were given the military designation C-98. Since the Pan Am pilots and crews had extensive expertise in using flying boats for extreme long-distance, over-water flights, the company's pilots and navigators continued to serve as flight crew. In 1943, President Franklin D. Roosevelt traveled to the Casablanca Conference in a Pan-Am crewed Boeing 314. Winston Churchill also flew on the aircraft several times, adding to the aircraft's fame during the war.[4]

After the war, several Clippers were returned to Pan American hands. However, even before hostilities had ended, the Clipper had become obsolete. The introduction of long-range airliners such as the Lockheed Constellation and Douglas DC-4, together with a prodigious wartime runway construction program, made the flying boat all but obsolete. The new landplanes were relatively easy to fly, and did not require the extensive pilot training programs required for seaplane operations. One of the 314's most experienced pilots said, "We were indeed glad to change to DC-4s and I argued daily for eliminating all flying boats. The landplanes were much safer. No one in the operations department... had any idea of the hazards of flying boat operations. The main problem now was lack of the very high level of experience and competence required of seaplane pilots"[5] The 314 was removed from scheduled service in 1946 and grounded permanently in 1950. Of the 12 aircraft built, three were lost to accidents, although only one of those resulted in fatalities, with 24 perishing in Lisbon, Portugal, 22 February 1943. The last remaining four to six sat for long time on San Diego's Lindbergh Field.Template:Fact They were eventually sold to a scrap dealer.

Howard Hughes attempted to buy a 314 before the war, but was unsuccessful. One source states that Hughes eventually succeeded in purchasing a 314 after the war and put it in a hanger in San Diego. It never flew, and was later scrapped.Template:Fact Except for some bits of scrap metal housed in museums, nothing remains of the 12 Boeing 314 aircraft.


Model 314
Initial production version with 1,500 hp (1,119 kW) Double Cyclone engines, six built
Model 314A
Improved version with 1,600 hp (1,193 kW) Double Cyclones with larger-diameter propellers, additional 1,200 US gal (4542 litres) fuel capacity, and revised interior, six built


  • Pan Am
  • BOAC
  • World Airways
  • Universal Airlines
  • American International Airways



  1. British Airways Concorde. Travel Scholar, Sound Message, LLC,. Retrieved: 19 August 2006.
  2. Masland, William M. Through the Back Doors Of The World In A Ship That Had Wings. New York: Vantage Press, 1984. ISBN 0-53305-818-X.
  3. Brock 1978, ch. VI.
  4. Hardesty 2003, pp. 37–41.
  5. Brock 1978, p. 224. Brock also reports cheap postwar availability to Pan Am of DC-4s and "Connies" was an important factor.


  • Bridgeman, Leonard. “The Boeing 314-A Clipper.” Jane's Fighting Aircraft of World War II. London: Studio, 1946. ISBN 1-85170-493-0.
  • Brock, Horace. Flying the Oceans: A Pilot's Story of Pan Am, 1935-1955. New York: Jason Aronson, Inc., 3d edition: 1978, ISBN 0-87668-632-3.
  • Dorr, Robert F. Air Force One. New York: Zenith Imprint, 2002. ISBN 0-76031-055-6.
  • Hardesty, Von. Air Force One: The Aircraft that Shaped the Modern Presidency. Chanhassen, Minnesota: Northword Press, 2003. ISBN 1-55971-894-3.

External links[]

W2 This article includes material from It is republished here under the Gnu Free Documentation Licence.