The Yankee Clipper flew across the Atlantic on a route from New York to Southampton. The inaugural trip occurred on June 24, 1939.
The Yankee Clipper crashed February 22, 1943 in Lisbon, Portugal. During the war the Yankee was assigned to the navy and allowed to continue passenger service between the United States and Portugal (indirectly serving all Europeans able to reach Lisbon). On February 22, 1943, after completing its 241st transatlantic flight, the Yankee Clipper circled for a landing on the Tagus River in Lisbon, Portugal. Her port wing tip skimmed the water, dug in, and she slammed into the river, breaking into several pieces, and sank inside of 10 minutes.
Twenty-four persons died; 15 survived. Among the survivors was singer Jane Froman who was heading a seven-member entertainment troupe for Camp Shows, Inc. Although seriously injured in the accident, Froman recovered enough to continue her singing career and later was the subject of a popular biographical movie, With a Song in My Heart, starring Susan Hayward as Froman.
Among those who died were Tamara Drasin, the singer and Broadway actress who had introduced Jerome Kern's song "Smoke Gets in Your Eyes." The captain of the Yankee Clipper was blamed for the accident and dismissed by Pan American Airways.
The Boeing 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 that bomber's 850 hp (640 kW) Pratt & Whitney R-1830 radial engines with the more powerful 1,600 hp (1,194 kW) Wright R-2600 Twin Cyclone. The Clipper's triple tail was chosen after Boeing had 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 - namely 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 plane 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. 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 (about $9,590 in year 2006 dollars). Compare the Concorde, which was priced at around $10,000 for a round trip.
Crew: 11, including 2 cabin stewards
Daytime: 68 passengers
Nighttime: 36 passengers
Payload: 10,000 lb (4,500 kg) of mail and cargo
Length: 106 ft 0 in (32.33 m)
Wingspan: 152 ft 0 in (46.36 m)
Height: 20 ft 4½ in (6.22 m)
Wing area: ft² (m²)
Empty weight: 48,400 lb (21,900 kg)
Loaded weight: 84,000 lb (38,000 kg)
Powerplant: 4× Wright R-2600-3 radial engines, 1,600 hp (1,200 kW) each
Maximum speed: 210 mph (180 knots, 340 km/h)
Cruise speed: 188 mph (163 knots, 302 km/h) at 11,000 ft (3,400 m)
Range: 3,685 mi (3,201 nm, 5,896 km) normal cruise
Service ceiling: 19,600 ft (5,980 m)