China Clipper

by Robert Gandt

  Even before the China Clipper entered commercial service, Trippe was shopping for a new airplane. He ordered his purchasing department to send specifications to aircraft manufacturers for a new flying boat with a range of 4,800 miles, that could carry 8,000 pounds of cargo and mail, with accommodations for no fewer than fifty passengers. As an inducement, a prize of $50,000 would go to the winning design. The expenses of the losers would not be reimbursed. “I believe in tying the bag of oats out front,” said Trippe.1

  Glenn L. Martin’s entry, an enhanced version of the M-130, was summarily rejected. The Martin design was judged to be unambitious, short of the desired passenger capacity, and lacking the futuristic innovations Pan American sought in their next flying boat. In any case, it was too expensive for Juan Trippe’s parsimonious taste.

  Glenn Martin, with some justification, was outraged. He had taken a loss on his deal with Trippe to build the M-130. The shortfall, he had expected, would be recouped with subsequent orders of the M-130 or its derivatives. Trippe, by declining to exercise options on Martin flying boats, was dealing Martin a nearly fatal economic blow. Dismissing any notions of loyalty, Trippe had opened the field to all newcomers.

  The design submitted by Igor Sikorsky was clearly the most advanced of all the entries and won the vote of Lindbergh, head of Pan American’s technical committee. But a flying boat as advanced as Sikorsky’s would require at least four years of development time. Such a luxury could not be afforded if Pan American were to proceed with its plans. Sikorsky’s proposal joined Martin’s in the trash bin.

  One of the newcomers, the Boeing Company of Seattle, Washington, had not responded to the design request. Boeing’s engineering department was preoccupied with the development of the Model 294, the Army Air Corps “Project X” that was to become the XB-15, and the Model 299 that would be the prototype B-17. But then an engineer named Wellwood Beall, who had been diverted to sales work, came home from an assignment in China where he had gone to deliver ten export versions of the Boeing P-26 “Peashooter.” When Beall heard of Pan American’s expired deadline, he made the flying boat request his personal project.

  On his own, Beall produced a preliminary design study for a Boeing flying boat. His proposal incorporated the already-built XB-15 wing. Pan American’s requirements stipulated the new Wright R-2600 Double Cyclone fourteen-cylinder, twin-row engine, producing 1,500-horsepower at takeoff. Indeed, the only other proven engine in use on large airliners was the R-1830, installed on the Martin M-130, which would be inadequate for a flying boat of the size required by Pan American.2 Pan American had also specified the newly developed Hamilton Standard full-feathering constant-speed, three-bladed propeller. Beall mated these features to a double-deck hull, tail assembly, and Dornier Flossenstummel (sea wings).

  As his plans developed, Beall became an impassioned advocate of the new flying boat. His zeal finally won over Boeing’s president, Clair Egtvedt, who directed Beall to petition Pan American for an extension of the design competition deadline. On 9 May 1936, Beall, Egtvedt, and aerodynamicist Ralph Cram officially delivered the proposal for Boeing Model 314 to Pan American’s technical committee. Thereafter ensued the predictable head-butting with Pan American’s tight-fisted deal makers. On 31 July 1936, Juan Trippe announced that Boeing had received a contract for six 314s with an option for six more. Each aircraft carried a price tag of $618,908 with another $756,450 for spare engines and parts.

  Wellwood Beall, from whose vision the new flying boat was conceived, was named project engineer for the 314, heading a team of eleven engineers. The Beall team’s task began by mating a cantilevered, monoplane wing, derived from the XB-15, to an aircraft of slightly over 80,000 pounds maximum weight. This raised the original loading of the wing from twenty-five pounds per square foot of wing area on the XB-15 to twenty-eight pounds per square foot on the 314, a performance enhancement that would be accommodated by the powerful new Wright R-2600 engines.3

  The Wright engines, specified by Pan American in its original design request, were still untested on commercial aircraft, though they had been used in military airplanes. The new engines, if Wright’s specifications proved correct, would have the lowest specific fuel consumption (measured in pounds of fuel consumed per horsepower/hour) of any engine in service. They would also be the first commercial engines to require 100-octane gasoline.

  The Hamilton Standard full-feathering propeller negated one of the worst nightmares of over-ocean airmen. Even though controllable-pitch propellers had been in use for several years, there was still no way to prevent them from “windmilling” in the event of engine failure except by using a propeller “brake.” A windmilling propeller increased the total drag of an aircraft by a quantum factor and usually destroyed an already-damaged engine. The full-feathering propeller allowed the blades to turn edgewise to the airstream, stopping rotation and virtually eliminating the drag of the propeller.

  The problem of sufficient propeller clearance from the water—a constant since the first flying boats—had been addressed in earlier aircraft by either mounting the engines atop the wing, as with the Dornier series, or by installing the engines in the wing and mounting the wing above the fuselage on a faired pylon, as with the Sikorsky S-42 and the Martin M-130. This choice demanded the use of struts to stabilize the wing, which, combined with the superstructure atop the fuselage, added drag and weight to the structure. The Boeing team chose to follow the lead of more recent designs like the Sikorsky XPBS-1 and the Consolidated XPB2Y-1 that used a deep, streamlined hull with sufficient height from the water to mate the wing directly to the upper fuselage. The engine nacelles could then be smoothly faired into the wing’s leading edge.

  A feature seen on the Dornier Do X but never used before on an American transport was an in-flight access to the engines. The 314’s wing had sufficient thickness to allow the flight engineer to crawl through a passageway to the accessory section of each engine and perform in-flight maintenance.

  In her initial configuration, the 314 had a maximum weight of 82,500 pounds (later 84,000). Her 152-foot wing tapered to smoothly rounded tips and was aluminum-covered from the rear spar forward and fabric aft. With an area of 2,867 square feet, the broad wings supported a load of 28.78 pounds per square foot (later, 29.30). The outer bays of the wing were watertight compartments—a feature that would prove fortuitous during the 314’s first trials. The fuselage, measuring 106 feet long, was constructed as an integral unit with the wing’s center section and inboard nacelles. Her hull, instead of being compartmented to prevent flooding as with most flying boats, was given a double bottom like a ship’s hull.4

  The fully cantilevered horizontal stabilizer was metal-skinned and attached as one unit to the top of the after hull. In the initial configuration, a single oval-shaped vertical stabilizer and rudder were attached to the top of the horizontal surface.

  The great depth of the hull permitted a double-deck configuration with compartments for passengers and crew members on separate levels. In a short-range configuration, the 314 was intended to carry seventy-four passengers. For long trips she could accommodate thirty-four in sleeping berths as plush and roomy as Pullman compartments.

  On the upper level was the flight deck, separated by a door from the crew quarters, baggage, and mail compartments. This level alone contained more space than the entire cabin of a DC-3. The flight deck was a roomy compartment—twenty-one feet long and nine feet wide—with a curtain that could be drawn between the pilot and copilot. The after flight-deck compartment was shared by the navigator, flight engineer, and radio operator. A spiral staircase, thirty years in advance of the Boeing 747’s winding stairway, led from the radio operator’s station down to the main passenger deck.

  Though the 314 did not equal the Dornier Do X in overall size, she was the largest commercial flying boat ever constructed in the United States. She was destined to become the most successful of all the great flying boats.

  By early June 1938, the 314 was rea
dy for launching. In Puget Sound off Duwamish Head, Boeing’s chief test pilot, Edmund Allen, powered the big flying boat into the open water. Behind the aircraft trailed a procession of picket boats carrying photographers, technicians, and in one of them Wellwood Beall and Pan American’s Andre Priester.

  During a taxi test with a strong breeze off the port wing, the flying boat suddenly heeled to the right, submerging the right wingtip and nearly dousing the outboard engine. Though Allen managed to raise the wing with thrust from the right engines, the left wing then dipped. Allen was forced to cut all four engines. To maintain stability, he sent life-jacketed crewmen out the navigation hatch and onto the wing to level the aircraft.

  It was hoped that this bizarre tendency could be attributed to the light fuel load and the fact that the sea wings were empty of fuel. But during the next day’s tests, the same problem occurred. It became increasingly obvious that the fault lay in the position and planing angle of the sea wings.

  The trials proceeded nonetheless. On the evening of 7 June, Allen opened the four throttles and the 314 skimmed briefly across Puget Sound, then lifted. To observers from below, the maiden flight appeared uneventful. For thirty-eight minutes Allen kept the big boat airborne, then gently returned her to the smooth waters of Lake Washington.

  There were problems. “We had power to spare,” Allen said, “but when I got off the water I couldn’t turn.” He had been forced to use differential thrust on the four Wright engines to maintain directional control. The single rudder on the big flying boat’s tail had been ineffective.5

  Beall’s engineering team went back to work. A new empennage configuration was tested, this one with the single vertical fin replaced by twin vertical stabilizers mounted at each outboard tip of the horizontal surface. But more flight testing proved that the double fin still lacked adequate directional control. Finally the center vertical stabilizer was restored with the twin outboard fins still in place. This triple-fin arrangement worked—to the great relief of Wellwood Beall and his team—providing full directional authority to Boeing’s big boat.

  Meanwhile, the earlier problem, the disturbing matter of lateral instability on the water, required an alteration in the position and planing angle of the sea wings. The fix was duly accomplished, and further tests showed that the 314 had, in fact, shed the irksome tendency to plunge her wingtips into the ocean.

  These were costly changes both in time and development funds. Not until January 1939, nearly a year behind schedule, was the first 314 delivered. By June 1939 all six 314s in the initial order had been delivered. In order of construction, they were the Honolulu Clipper, the California Clipper, the Yankee Clipper, the Atlantic Clipper, the Dixie Clipper, and the American Clipper.

  On 3 March 1939, at the Tidal Basin in Washington, D.C., Eleanor Roosevelt smacked a bottle of what was said to be water from the seven seas against the bow of the Yankee Clipper. Three weeks later the newly christened flying boat left New York to fly its first transatlantic round trip.

  The second series of six were already in production. These were 314A models and would differ from the first series with their larger fuel tanks (25,500 pounds), more powerful Wright Double Cyclones (1,600 horsepower), and increased maximum gross weight (84,000 pounds).

  The 314A, with her empty weight of 49,149 pounds, possessed a load-to-tare ratio of 41:59, a seemingly unremarkable ratio until it is considered that the giant ship could carry a useful load of 34,851 pounds, an astounding capability that outclassed any airliner in the world. Included in this useful load was a fuel capacity of 4,200 gallons, which, at normal cruising speed (280 gallons per hour) and weight, translated to a still-air range of over 3,000 miles.6

  Juan Trippe now had the ultimate weapon in his clash with the European governments. For three years His Majesty’s government had remained steadfast in upholding the onerous Clause H, which bound Imperial Airways and Pan American to simultaneous introduction of transatlantic service. Despite Britain’s Mercury-Maia project, their experiments with in-flight refueling, and the continued development of the Empire-class boats, Imperial Airways still lacked commercial transatlantic capability. And Pan American, bound by Clause H, could not unilaterally begin service.

  Pan American’s rights to France had likewise been tethered to the reciprocity issue. But at the end of 1938, almost as the first 314 was passing into Pan American’s custody, the French government relented, giving Pan American temporary landing rights in Marseille. In return, Air France, which still had no transatlantic passenger-carrying capability, would have rights to the United States whenever they were ready. Thus, Pan American would fly the new 314 to mainland Europe, to a port only three hours from Paris. Though Trippe still had no landing rights in Britain, he had outflanked the British.

  A sigh of resignation could be heard in the halls of the British Air Ministry. With more hope than faith, the Ministry announced that Imperial Airways, on an experimental basis, would begin service over the North Atlantic in June 1939. If Pan American was prepared to commence service sooner, they could proceed. Clause H was waived.7

  A certificate of public convenience and necessity was duly issued by the Civil Aeronautics Authority (CAA) granting Pan American operating authority to Great Britain and France, with London and Marseille as terminal points. As intermediate stops, Pan American was entitled to use the Azores, Shediac, Botwood, and Foynes.

  On 20 May 1939, the twelfth anniversary of Lindbergh’s solo Paris flight, the Yankee Clipper waited at her moorings at Port Washington in Manhasset Bay, New York. It was noon on a sunny Saturday. After years of frustration, Pan American was about to operate a scheduled flight over the North Atlantic. Like the Pacific inaugural of the China Clipper, a script had been produced that invoked symbolism and hyperbole.

  “The Yankee Clipper is ready, sir,” reported Captain Arthur Laporte. Before a gathered throng at Pan American’s new marine terminal, Trippe handed over the ship’s documents. He ordered the captain to cast off. Laporte and his crew of fourteen marched two by two down the ramp to the waiting Yankee Clipper.

  In brilliant sunshine, the Yankee Clipper lifted from the bay, then veered toward the New York World’s Fair, passing 500 feet over the heads of the gawking spectators. Radiotelephone communications had recently come into use in terminal areas. The Yankee Clipper’s crew received congratulations over the air from the chairman of the CAA. Laporte replied, following his script, “We are proceeding for Europe.”8

  Carrying 1,800 pounds of mail, the Yankee Clipper reached Marseille, via the Azores and Lisbon, on 22 May 1939. Three days later Laporte and his crew flew the 314 on the return trip, transporting a ton of United States–bound mail, thus completing the inaugural round trip transatlantic air mail service.

  There were more firsts. In June the Yankee Clipper, commanded by Captain Harold Gray, who had succeeded Ed Musick as chief pilot, flew the northern route to Europe, this time carrying non-revenue passengers including Juan Trippe and a contingent of official government and business guests. On 28 June, amid fanfare and newsreels, the Dixie Clipper, flown by Captain R. O. D. Sullivan (who had taken the first S-42 to Wake Island and who was Ed Musick’s first officer on the M-130 inaugural) took off for Marseille with the first paying transatlantic passengers. The event made page one of the New York Times.9

  Two of the new 314s, the Honolulu Clipper and the California Clipper, were tagged for the Pacific service, depleted by the losses of the Hawaii Clipper and Ed Musick’s Samoa Clipper. By the time the second group of six, the 314As, were completed, war had come. Three of the flying boats were sold to British Overseas Airways Corporation (recently nationalized airline composed of the former Imperial Airways and British Airways) and would be christened Berwick, Bangor, and Bristol. Pan American took possession of the remaining three 314s, the Pacific Clipper, the Anzac Clipper, and the Capetown Clipper.

  Like the Martin M-130 four years earlier, the 314 bathed in a brief shower of publicity. Each of her inaugural flights was atte
nded by gala fanfare and media coverage. But as her ocean crossings became as routine as a railroad timetable, the public’s attention waned. There were more urgent matters in the headlines. The peaceful conquest of the oceans had been overshadowed by another war.

  23

  War Day

  Sunday morning, 7 December 1941. It was business as usual in the central Pacific. Captain H. Lanier Turner, commanding the Boeing 314 Anzac Clipper, was inbound to Honolulu with his crew of ten and seventeen passengers. In the cabin, breakfast was being served to the passengers, mostly vacationers. They were an hour out of Pearl Harbor when radio officer W. H. Bell received the electrifying news: Pearl Harbor, their destination, was under attack by Japanese aircraft.

  Farther to the west, the Philippine Clipper, a Martin M-130 commanded by Captain John Hamilton, had just lifted from the lagoon of Wake Island, bound for Guam. Hamilton expected a routine flight in clear skies all the way to Guam. But then, twenty minutes into the flight, Hamilton received new orders by radio. He was to return immediately to Wake and prepare to evacuate all Pan American personnel. Pearl Harbor, he was told, had been bombed.

  In Hong Kong, beyond the international date line, it was already Monday, 8 December. Captain Fred S. Ralph and his crew of six had been alerted before dawn by the Pan American station manager. A Japanese attack on Hong Kong was expected. Ralph should muster his crew at Kai Tak airport and prepare to take off as soon as possible in the Hong Kong Clipper, a Sikorsky S-42B. Ralph had completed his preflight preparations. But as he stood on the ramp at Kai Tak waiting for the Sikorsky to be loaded, he heard the unmistakable drone of incoming warplanes.

  For Captain Robert Ford, the thirty-five-year-old captain of the Pacific Clipper, the news came while he was midway between New Caledonia and New Zealand. The Japanese, he learned by radio, were on the move throughout the Far East. Ford immediately posted lookouts and ordered the Boeing 314’s radios silenced. Grimly he continued toward Auckland, not knowing what to expect.