Pan American Airways’ Martin M-130, China Clipper, at Macau, 1937.
28 April 1937: The first transpacific flight by a commercial passenger airliner is completed when Pan American Airways’ Martin M-130, China Clipper, arrived at Hong Kong. The flight had departed San Francisco Bay, California, on 21 April with 7 revenue passengers and then proceeded across the Pacific Ocean by way of Hawaii, Midway Island, Wake Island, Guam, Manila, Macau, and finally Hong Kong. The Reuters news agency briefly reported the event:
AIR LINK AROUND WORLD FORGED.
China Clipper Lands At Hong Kong.
Hong Kong, April 28.
The Pan-American Airways flying boat China Clipper landed at 11:55 this morning from Manila and Macao. This links the Pan-American and Imperial Airways, completing the commercial air link round the world. —Reuter.
—The Straits Times, 28 April 1937, Page 1, Column 4.
Pan American Airways’ China Clipper, a Martin M-130, NC14716, over Oakland, California. (Clyde Herwood Sunderland/Library of Congress 94509042)
The Oakland Tribune reported:
AIR CLIPPER SPANS SEAS TO HONGKONG
U.S. MAIL TO CHINA LANDED IN SIX DAYS
Plane Crew Feted at End Of Historic Hop From U.S. Via Philippines
HONGKONG, April 28.—(AP)—A 30-year dream of ’round-the-world air service became reality today with the arrival of the Hongkong Clipper from Manila on the first regular flight between the two cities.
The clipper, bridging the last 700-mile gap in the America-Asia service, placed the final link in an airplane chain whereby it is possible to encircle the world in less than a month, using scheduled commercial planes.
The craft brought 2500 pounds of American cargo, including 100,000 letters and newspapers from the United States only six days old. The papers left Alameda, Calif., last Thursday aboard China Clipper, being transferred to the Hongkong Clipper at Manila. ¹
A large crowd welcomed the clipper at Kaitak Airport. Included were Acting Governor N. L. Smith and representatives of all of the colony’s government and commercial activities.
The clippers’ pilot, A. E. Laporte, and crew were escorted to a dais at the hangar, where the acting governor gave a speech of welcome.
The plane, on its return flight on Thursday, is expected to carry 2500 pounds of cargo, including 40,000 letters.
At a reception for the fliers, the acting governor said:
“We are celebrating the welding of the last link in world air communication. The lessening of the physical gaps is the surest way of ending misunderstandings which have occurred between nations in the past.
“Hongkong offers congratulations, welcomes this American transpacific air service and hopes it will be another bond in the chain of goodwill.”
Laporte said the Manila-Hongkong flight was “uneventful,” despite poor weather conditions necessitating intermittent blind flying.
The China Clipper, NC14716, was the first of three Martin M-130 four-engine flying boats built for Pan American Airways and was used to inaugurate the first commercial transpacific air service from San Francisco to Manila in November, 1935. Built at a cost of $417,000 by the Glenn L. Martin Company in Baltimore, Maryland, it first flew on 20 December 1934, and was delivered to Pan Am on October 9, 1935.
The airplane was operated by a flight crew of 6 to 9, depending on the length of the flight, plus cabin staff, and could carry 18 passengers on overnight flights or a maximum 36 passengers.
Martin M-130 China Clipper, NC14716, at Honolulu, Oahu, Hawaiian Islands. (Unattributed)
The Martin M-130 was 90 feet, 10.5 inches (27.699 meters) long with a wingspan of 130 feet, 0 inches (39.624 meters). It was 24 feet, 7 inches (7.493 meters) high. Its maximum takeoff weight was 52,252 pounds (23,701 kilograms).
The flying boat was powered by four air-cooled, supercharged, 1,829.389-cubic-inch displacement (29.978 liters) Pratt & Whitney Twin Wasp S2A5-G engines. These were two-row, 14-cylinder radial engines with a compression ratio of 6.7:1. The S2A5-G was rated at 830 horsepower at 2,400 r.p.m., and 950 horsepower at 2,550 r.p.m. for takeoff, burning 87-octane gasoline. They drove three-bladed Hamilton Standard Hydromatic constant-speed propellers through a 3:2 gear reduction. The engine was 3 feet, 11.88 inches (1.216 meters) in diameter and 4 feet, 8.75 inches (1.441 meters) long. It weighed 1,235 pounds (560 kilograms).
The airplane had a maximum speed of 180 miles per hour (290 kilometers per hour), and a cruise speed of 130 miles per hour (209 kilometers per hour). The service ceiling was 10,000 feet (3,048 meters) and its range was 3,200 miles (5,150 kilometers).
Martin M-130, NC14716, China Clipper, moored at some distant exotic locale. (Unattributed)
¹ There may be confusion as to which airplane was flown from Manila to Hong Kong. Most newspapers identified it as China Clipper, while the Oakland Tribune called it Hongkong Clipper.
Pan American’s Hong Kong Clipper was a Sikorsky S-42, NC823M, which had entered service in December 1934. Many newspapers dated 28 April 1937 showed a photograph of NC832M arriving at Auckland, New Zealand, after a four-day, 7,000-mile survey flight from the United States.
Entering service in 1934, the airline had originally named the NC823M West Indies Clipper. This was changed to Pan American Clipper, and later, Hong Kong Clipper. The airplane crashed on takeoff and sank near Antilla, Cuba, 7 August 1944.
Pan American Airways System’s Sikorsky S-42, NC832M, over San Francisco Bay, 1935. (NASM SI-90-3001)
Pan American Clipper NR823M over San Francisco-Oakland Bay Bridge, en route to Hawaii on the first survey flight, 1935. Photographed by Clyde Herwood Sunderland, Jr. (1900–1989). (National Air and Space Museum SI-90-3001)
16 April 1935: At 3:42 p.m. Pacific Standard Time (23:42 Greenwich Mean Time), Pan American Airway’s Sikorsky S-42 Clipper, NC823M, pulled away from the dock at Alameda, California, on a survey flight to determine the feasibility of long range passenger flights across the Pacific Ocean.
After a 30 second takeoff run of about 1,700 feet (518 meters), the S-42 lifted from the waters of San Francisco Bay at 3:50 p.m., Pacific Standard Time (23:50 G.M.T.).
Crew of the first Pan American Airways Sikorsky S-42 survey flight in Hawai’i , 7 April1935. Left to right: Radio Officer Wilson Turner Jarboe Jr.; Junior Officer Harry R. Canaday; First Officer Robert Oliver Daniel (“Rod”) Sullivan; Captain Edwin Charles Musick; Navigator Fred Joseph Noonan; Engineer Officer Victor A. Wright. (SFO Museum)
The Clipper’s crew were Captain Edwin Charles Musick; First Officer Robert Oliver Daniel (“Rod”) Sullivan; Fred Joseph Noonan, navigator; Victor A. Wright, flight engineer; Harry R. Canaday, junior flight officer; and Wilson Turner Jarboe, Jr., radio operator.
The airplane carried 150 pounds (68 kilograms) of mail and two tons (1,814 kilograms) of mechanical and engineering equipment for Pan Am’s base in Hawaii. Postage for the approximate 10,000 letters varied from $1.00 to $2.50. ($22.80 – $56.99 in 2024 U.S. dollars). The Clipper carried 3,000 gallons (11,356 liters) of gasoline and 300 gallons (1,136 liters) of oil.
The flight was made at altitudes varying from 4,000 to 8,500 feet (1,219 to 2,591 meters).
Pan American Airways’ Sikorsky S-42 NC832M passes Diamond Head on the island of Oahu, Territory of the Hawaiian Islands, in 1935. (Smithsonian Institution National Air and Space Museum PP-1-8-013/Hawaii State Archives)
NC823M arrived overhead Diamond Head, Territory of the Hawaiian Islands, at 7:05 a.m., Hawaii Standard Time (17:35 G.M.T.), 17 April. [In 1935, Hawaii Standard Time was G.M.T. + 10 hours, 30 minutes] The S-42 was joined by an escort of five patrol planes from the U.S. Navy Patrol Squadron 10 (VP-10) and ten “pursuit” planes. (These were not not specified in contemporary newspaper articles, but the Navy planes were probably Consolidated P2Y-1s, while the “pursuits” were most likely U.S. Army Boeing P-26 monoplanes.)
The Clipper circled the city at about 1,000 feet (305 meters). It spent 52 minutes circling the city, Waikiki Beach, the Ewa plantation, and the U.S. Army’s Schofield Barracks.
A U.S. Navy Consolidated P2Y-1 of Patrol Squadron 10, circa 1934. (U.S. Navy)
The S-42 touched down at Pearl Harbor at 7:57 a.m., H.S.T., 17 April, (10:27 a.m., P.S.T./17:27 GMT.) after a flight of 17 hours, 45 minutes.¹ Flying a Great Circle Route, the total distance flown was approximately 2,090 nautical miles (2,405 statute miles/3,870 kilometers).² The average speed was about 117.75 knots (135.5 miles per hour/218 kilometers per hour).
This image depicts the Great Circle Route from the Alameda Naval Air Station (NGZ) to Honolulu International Airport. (Great Circle Mapper)
After landing, the flying boat shut down two of its engines and taxied to the seaplane ramp at Ford Island.
Pan American Clipper NR823M at Pearl Harbor, Hawaii, 17 April 1935. (Pan Am Historical Foundation)
NC823M was only the twelfth airplane to successfully fly from California to Hawaii. The first was the U.S. Army’s Atlantic-Fokker C-2, Bird of Paradise, on 29 June 1927.³ For reference, VP-10s six P2Y-1s had taken 24 hours, 45 minutes to reach the islands in 1934.
The Sikorsky S-42 was a four-engine long-range flying boat built for Pan American Airways by the Vought-Sikorsky Aircraft Division of United Technologies at Stratford, Connecticut. It was 67 feet, 8 inches (20.625 meters) long with a wingspan of 114 feet, 2 inches (34.798 meters). The S-42 had an empty weight of 18,236 pounds (8,272 kilograms) and gross weight of 38,000 pounds (17,237 kilograms). It could carry up to 37 passengers.
The S-42 was powered by four air-cooled, supercharged, 1,690.537-cubic-inch-displacement (27.703 liters) Pratt & Whitney Hornet S1E-G nine-cylinder radial engines with a compression ratio of 6.5:1. The S1E-G had a Normal Power rating of 750 horsepower at 2,250 r.p.m., to 7,000 feet (2,134 meters), and 875 horsepower at 2,300 r.p.m., for Takeoff. The engines drove three-bladed Hamilton Standard constant-speed propellers through a 3:2 gear reduction. The S1E-G was 4 feet, 1.38 inches (1.254 meters) long, 4 feet, 6.44 inches (1.383 meters) in diameter, and weighed 1,064 pounds (483 kilograms).
The S-42 had a cruise speed 165 miles per hour (266 kilometers per hour) and maximum speed of 188 miles per hour (303 kilometers per hour) at 5,000 feet (1,524 meters). The service ceiling was 16,000 feet (4,877 meters). It could maintain 7,500 feet (2,286 meters) with three engines. Its range was 1,930 miles (3,106 kilometers).
Ten Sikorsky S-42, S-42A and S-42B flying boats were built for Pan Am. None remain in existence.
¹ “Flight time” is generally defined as from the time the aircraft first moves under its own power for the purpose of flight until it comes to rest after landing. In this case, the flight time commenced when the S-42 pulled away from the dock in Alameda, not the time it actually lifted from the water of San Francisco Bay.
² In actuality, the S-42 taxied on San Francisco Bay before taking off, then flew west over the Golden Gate Bridge before turning on its course to Hawaii. It arrived overhead Diamond Head on the island of Oahu before landing on the waters of Pearl Harbor. The actual distance flown is therefore an approximation.
³ Please see This Day in Aviation at https://www.thisdayinaviation.com/28-29-june-19/
11 January 1938: Pan American Airways’ Sikorsky S-42B NC16734, Samoan Clipper, took off from Pago Pago, American Samoa, enroute Auckland, New Zealand. The airplane had a crew of seven, commanded by Captain Edwin C. Musick, the airline’s senior pilot, and a cargo of mail.
About two hours out, the number four engine began leaking oil. Captain Musick ordered the engine shut down. The flight radioed that they were returning to Pago Pago. They never arrived. Wreckage, a large oil slick, various documents and articles of the crew’s clothing were found by the U.S. Navy seaplane tender USS Avocet (AVP-4), 14 miles (22.5 kilometers) west of the island. It was apparent that the S-42 had exploded in mid-air.
The cause of the explosion is not known with certainty but based on Captain Musick’s handling of a similar problem with one of Samoan Clipper‘s engines on an earlier flight, a possible cause can be suggested.
Pan American Airways’ Samoan Clipper. (Hawaii Aviation)
On the earlier flight, the number four engine had begun seriously overheating and Musick ordered the flight engineer to shut it down. Because of the decreased power with only three engines, Captain Musick ordered the crew to begin dumping fuel to decrease the weight of the airplane before landing.
Pan American had tested the fuel dumping characteristics of the Sikorsky S-42 using dye, and had learned that because of the air flow patterns around the wings, the fluid tended to accumulate around the trailing edge of the wings and that it could actually be sucked into the wings themselves.
As fuel was being dumped on the previous flight, fuel vapors were present in the cabin, requiring all electrical systems to be shut off—even though it was night. Liquid gasoline was also dripping into the cockpit from the wing above.
Pan American Airways’ Sikorsky S-42B NC16734 at Pago Pago, 24 December 1937. (Unattributed)
Samoan Clipper had been very heavy with fuel when it departed for the long transoceanic flight to Auckland. Presuming that Captain Musick once again ordered fuel to be dumped prior to landing back at Pago Pago, and that the vapors collected around the wings, the fuel could have been detonated by the electrical motors which were used to lower the flaps for flight at slower speed, or by coming into contact with the hot exhaust of the engines.
Two independent investigations were carried out by Pan American and by the United States Navy, and both came to this conclusion.
Captain Edwin Charles Musick, Chief Pilot, Pan American Airways. (1894–1938)
There were no survivors of the explosion. Killed along with Captain Musick were Captain Cecil G. Sellers, Second Officer P.S. Brunk, Navigator F.J. MacLean, Flight Engineer J.W. Stickrod, Flight Mechanic J.A. Brooks and Radio Operator T.D. Findley.
The Sikorsky S-42B was a four-engine long-range flying boat built for Pan American Airways by the Vought-Sikorsky Aircraft Division of United Technologies at Stratford, Connecticut. It was 68 feet (20.726 meters) long with a wingspan of 118 feet, 2 inches (36.017 meters). The S-42 had an empty weight of 19,764 pounds ( kilograms) and gross weight of 38,000 pounds ( kilograms). It could carry up to 37 passengers.
The S-42B was powered by four air-cooled, supercharged, 1,690.537-cubic-inch-displacement (27.703 liters) Pratt & Whitney Hornet S1E-G nine-cylinder radial engines with a compression ratio of 6.5:1. The S1E-G had a Normal Power rating of 750 horsepower at 2,250 r.p.m., to 7,000 feet (2,134 meters), and 875 horsepower at 2,300 r.p.m., for Takeoff. The engines drove three-bladed Hamilton Standard constant-speed propellers through a 3:2 gear reduction. The S1E-G was 4 feet, 1.38 inches (1.254 meters) long, 4 feet, 6.44 inches (1.383 meters) in diameter, and weighed 1,064 pounds (483 kilograms).
The S-42B has a cruise speed 165 miles per hour (266 kilometers per hour) and maximum speed of 188 miles per hour (303 kilometers per hour) at 5,000 feet (1,524 meters). The service ceiling was 16,000 feet (4,877 meters), and it could maintain 7,500 feet (2,286 meters) with three engines. Its range was 1,930 miles (3,106 kilometers).
Boris Vasilievich Sergievsky. (Test & Research Pilots, Flight Test Engineers)
During flight testing of the S-42, Sikorsky test pilot Boris Vasilievich Sergievsky, with co-pilot Raymond B. Quick, set three Fédération Aéronautique Internationale world records for payload and altitude.¹ Later, Captain Musick, with Sergievsky and world-famous aviator Charles A. Lindbergh, flew the S-42 to set eight Fédération Aéronautique Internationale world records for speed.²
Ten Sikorsky S-42, S-42A and S-42B flying boats were built for Pan Am. None remain in existence.
Pan American Airways’ Sikorsky S-42B NC16734, Samoan Clipper, moored at Mechanic’s Bay, Auckland, New Zealand, December 1937. The flying boat in the background is a Short S.23 Empire, G-ADUT, named Centaurus. (Turnbull Library)
¹ 26 April 1934 FAI Record File Numbers: 11583: Greatest load to 2,000 meters (6,562 feet): 7,533 kilograms (16,652 pounds). 17 May 1934: 11582 and 11978: Altitude with a 5,000 Kilogram (11,023 pounds) Load, 6,220 meters (20,407 feet).
² 1 April 1934 FAI Record File Numbers: 11517: Speed over a closed circuit of 1,000 Kilometers (621.3 statute miles), 253,60 km/h (157.58 m.p.h.); 11518: . . . with a 500 Kilogram (1,102 pounds) Payload, 253,60 km/h (157.58 m.p.h.); 11519: . . . with a 1,000 Kilogram (2,205 pounds) Payload, 253,60 km/h (157.58 m.p.h.); 11520: . . . with a 2,000 kilogram (4,409 pounds) Payload, 253,60 km/h (157.58 m.p.h.); 11521: Speed over a closed circuit of 2,000 Kilometers (1,242.7 statute miles), 253,18 km/h (157.32 m.p.h); 11522: . . . with a 500 Kilogram Payload, 253,18 km/h (157.32 m.p.h.); 11523: . . . with a 1,000 Kilogram Payload, 253,18 km/h (157.32 m.p.h.); 11524: . . . with a 2,000 Kilogram Payload, 253,18 km/h (157.32 m.p.h.).
Pan American Airways’ Martin M-130 flying boat, China Clipper (NC14716), leaving the Golden Gate enroute to Honolulu, 22 November 1935. Photographed by Clyde Herwood Sunderland, Jr. (1900–1989).
22 November 1935: The Pan American Airways flying boat, China Clipper, a Martin M-130, NC14716, departed Alameda, California (an island in San Francisco Bay) at 3:46 p.m., Friday, and arrived at Honolulu at 10:39 a.m., Saturday, completing the first leg of a five-day trans-Pacific flight to Manila in the Philippine Islands.
The aircraft commander was Captain Edwin Charles Musick, with First Officer Robert Oliver Daniel (“Rod”) Sullivan. The navigator was Frederick Joseph Noonan, who would later accompany Amelia Earhart on her around-the-world flight attempt. There were also a Second Officer and two Flight Engineers. The cargo consisted of 110,000 pieces of U.S. Mail.
Captain Edwin Musick and R.O.D. Sullivan, at the center of the image, next to the China Clipper before leaving San Francisco Bay with the first transpacific airmail, 22 November 1935. The three men at the right of the image are (left to right) Postmaster General James Farley; Assistant Postmaster General Harllee Branch; and Pan American Airways’ President Juan Trippe.
Pan Am personnel called the Clipper “Sweet Sixteen,” referring to its Civil Aeronautics Board registration number, NC14716. The airplane and Humphrey Bogart starred in a 1936 First National Pictures movie, “China Clipper.”
NC14716 was the first of three Martin M-130 four-engine flying boats built for Pan American Airways and was used to inaugurate the first commercial transpacific air service from San Francisco to Manila in November, 1935. Built at a cost of $417,000 by the Glenn L. Martin Company in Baltimore, Maryland, it was delivered to Pan Am on October 9, 1935. The airplane’s serial number was 558.
Pan American Airways’ Martin M-130m China Clipper, NC14716, over San Francisco, California. (Clyde Herwood Sunderland, Jr./Library of Congress 94509045)
The M-130 was operated by a flight crew of 6–9, depending on the length of the flight, plus cabin staff, and could carry 18 passengers on overnight flights, or a maximum 36 passengers.
Cutaway illustration of Pan American Airways’ Martin M-130 China Clipper. Detail from larger image. (National Air and Space Museum SI-89-1216-A)Martin M-130 3-view drawing. (Flight)
The Martin M-130 was 90 feet, 10.5 inches (27.699 meters) long with a wingspan of 130 feet, 0 inches (39.624 meters). It was 24 feet, 7 inches (7.493 meters) high. The total wing area was 2,315 square feet (215 square meters), including the “sea wings”. Its maximum takeoff weight was 52,252 pounds (23,701 kilograms).
The flying boat was powered by four air-cooled, supercharged Pratt & Whitney Twin Wasp S2A5-G two-row 14-cylinder radial engines with a compression ratio of 6.7:1. They had a normal power rating 830 horsepower at 2,400 r.p.m., and 950 horsepower at 2,550 r.p.m. for takeoff. They drove three-bladed Hamilton Standard Hydromatic constant-speed propellers through a 3:2 gear reduction. The S2A5-G was 3 feet, 11.88 inches (1.216 meters) in diameter, 4 feet, 8.75 inches (1.441 meters) long, and weighed 1,235 pounds (560 kilograms).
Martin M-130 NC14716, right rear quarter view.
The airplane had a cruise speed of 130 miles per hour (209 kilometers per hour) and a maximum speed of 180 miles per hour (290 kilometers per hour). The M-130’s service ceiling was 10,000 feet (3,048 meters). Its range was 3,200 miles (5,150 kilometers).
Martin M-130, NC14716, China Clipper, moored at some distant exotic locale. (Unattributed)
Boeing 314, California Clipper, NC18602, over Oakland, California, 1937. Photographed for Pan Am by Clyde Herwood Sunderland, Jr. (1900–1989).(Clyde Sunderland Photograph Collection, Library, University of California Berkeley)
3–4 November 1945: On the evening of Saturday, 3 November 1945, the Boeing 314 Honolulu Clipper, NC18601, departed Honolulu, Oahu, Territory of Hawaii, enroute to San Francisco, California. The flying boat was under the command of Captain Sanis E. (“Robby”) Robbins, Pan American Airways, with First Officer Wally Reed, Second Officer Dunbar Carpenter, Radio Officer Jack B. Crawford, First Engineer Dan W. Broadwater, Second Engineer Robert J. Dernberger. There were 13 passengers and 10 crew members on board. The flight to San Francisco was expected to take 11 hours.
Approximately 5 hours into the flight, the number 3 engine (starboard wing, inboard) began to backfire. It was shut down and the propeller feathered. Captain Robbins decided to return to Hawaii. A short while later, the number 4 engine (starboard wing, outboard) also started to malfunction. It continued to run but eventually it was also shut down.
With two engines inoperative, the airplane was unable to maintain altitude. At 11:07 p.m. local, Captain Robbins, in total darkness, brought the flying boat to a “masterful” landing on the relatively calm surface of the Pacific Ocean. There were no injuries. The airplane suffered minor damage to the port sea wing, and started taking on water.
California Clipper, NC18602, another Boeing 314, also enroute to San Francisco, orbited Honolulu Clipper‘s position to guide rescue ships to scene. The following message was broadcast from Pearl Harbor:
PAN AMERICAN CLIPPER DOWN AT SEA AT 040935Z POSITION 2749N 14802W. PLANE IN GOOD CONDITION. IS ABLE TO COMMUNICATE ON [frequency deleted] KCS VOICECALL C18601 ON [frequency deleted] KCS. INVESTIGATE SIGHTINGS REPORT PERTINENT INFO TO ORIGINATOR.
The United States Army transport ship, U.S.A.T. John Henry Payne sighted flares fired from the flying boat and quickly arrived on scene. The ship took all of the passengers on board. Ten crew stayed aboard flying boat.
USS Manila Bay (CVE 61), a Casablanca-class escort aircraft carrier under the command of Captain Leon Johnson, was approximately 60 miles (97 kilometers) away, and had been ordered to take charge of efforts to salvage the airplane.
On arrival, a whale boat was sent to remove the remaining crew members from the flying boat. Wind and waves had increased and it was feared that the boat might damage the hull of the flying boat, so a rubber life raft was used to transfer the Clipper‘s crew to the whale boat. Aircraft mechanics were sent from Manila Bay to attempt to repair the airplane, but were not successful.
A whale boat from USS Manila Bay approaches Honolulu Clipper, 4 November 1945. (U.S. Navy)
Plans were made to rig the airplane for towing. 200 fathoms (1,200 feet/366 meters) of 6-inch (15.2 centimeter) diameter hawser was rigged from the aircraft carrier to the nose of the flying boat. Stabilizing lines were tied to the propeller hubs of the outboard engines. Manila Bay began towing the Honolulu Clipper and was gradually able to increase speed to 6 knots (7 miles per hour/11 kilometers per hour). About an hour after sunset, at about 7:30 p.m., the tow line parted.
Darkness and rising seas made it impossible to rig a new tow. Manila Bay stood by awaiting arrival of USS San Pablo (AVP-30) (Commander Charles Robert Eisenbach), a Barnegat-class seaplane tender, on Tuesday, 6 January, then departed for Pearl Harbor.
Seaplane tender USS San Pablo (AVP-30) standing by Honolulu Clipper. (U.S. Navy)USS San Pablo approaches the undamaged Honolulu Clipper. (U.S. Navy)
During the several days that Honolulu Clipper was afloat in the open ocean, weather increased to the point that it was considered too hazardous to approach it in a small boat, so the aviation tender closed on the airplane directly to try to take it on tow. Unfortunately, San Pablo hit the clipper and caused significant damage.
Hawaii Clipper from the bridge of USS San Pablo. The starboard wing is damaged and the Number 4 engine is missing. (U.S. Navy)
With salvage impossible, the derelict Honolulu Clipper was now considered a hazard to navigation. It was sunk by 20 mm gun fire from San Pablo.
Honolulu Clipper was the prototype for the Boeing Model 314 series flying boat. It had been designed to carry a maximum of 76 passengers and a crew of 10 a distance of 5,200 miles at 184 miles per hour. The design used the wings and engine nacelles of Boeing’s experimental Model 294 (XB-15) very long-range heavy bomber.
The Boeing Model 314 was a large four-engine, high-wing monoplane flying boat designed and built by the Boeing Airplane Company to take off and land on water. It was 106 feet (32.309 meters) long with a wingspan of 152 feet (46.330 meters). It had a maximum take off weight of 82,500 pounds (37,421 kilograms).
Boeing 314 prototype NX18601 in original configuration. (Boeing Airplane Company)
The airplane was built at Boeing’s Plant 1, then transported by barge to Elliot Bay. It carried experimental registration NX18601. Test pilot Edmund Turney (“Eddie”) Allen made the first flight of the prototype on 7 June 1938. He reported that the flying boat had insufficient rudder control and that he had to vary engine power to turn it. The prototype was modified to a twin-tail configuration.
Boeing Model 314 NX18601 flying over Elliot Bay. Note the twin-tail configuration. (Boeing Airplane Company)
With two vertical fins and rudders, control was improved, but was still insufficient. A third, center, fin was added and this became the production configuration.
Prototype Boeing 314 NX18601 in triple-tail configuration, 24 November 1938. (U.S. Air Force/San Diego Air and Space Museum)
The Boeing 314 was powered by four air-cooled, supercharged, 2,603.737-cubic-inch-displacement (42.668 liter) Wright Aeronautical Division Cyclone 14 GR2600A2, two-row, 14-cylinder radial engines with a compression ratio of 7.1:1. They were rated at 1,200 horsepower at 2,100 r.p.m., and 1,550 horsepower at 2,400 r.p.m. for takeoff, burning 91/96 octane gasoline. These engines (also commonly called “Twin Cyclone”) drove three-bladed Hamilton Standard Hydromatic full-feathering constant-speed propellers with a diameter of 14 feet (4.267 meters) through a 16:9 gear reduction. The GR2600A2 was 5 feet, 2.06 inches (1.576 meters) long and 4 feet, 7 inches (1.387 meters) in diameter. It weighed 1,935 pounds (878 kilograms). The engines could be serviced in flight, with access through the wings.
The Boeing 314 had a maximum speed of 199 miles per hour (320 kilometers per hour), with a range of 3,685 miles (5,930 kilometers) at its normal cruising speed of 183 miles per hour (295 kilometers per hour). Its service ceiling was 13,400 feet (4,084 meters). The fuel capacity was 4,246 gallons (16,073 liters).
Boeing built six Model 314 and another six 314A flying boats for Pan American Airways and British Overseas Airways Corporation. Pan Am paid $549,846.55 for each 314, about $9,545,726.07 in 2017 dollars, and Boeing lost money on every one sold.
Honolulu Clipper was leased to the United States Navy by Pan American Airways, 17 December 1942, and assigned Bureau of Aeronautics serial number (“Bu. No.”) 48227. The airplane continued to be operated by Pan Am crews.
A Pan American Airways Boeing 314 at Hawaii. (San Diego Air and Space Museum)
Sanis E. (“Robby”) Robbins was born at Matthews, Indiana, 17 September 1898. He was the sixth of seven children of William S. Robbins, a real estate agent, and Sarah Ellen Brokaw Robbins.
Robbins enlisted as a Private, United States Army, at Camp Dodge, Iowa, 26 June 1916. He was promoted to Private First Class on 1 August 1916, and to Corporal, 18 December 1916. Corporal Robbins was hospitalized at Brownsville, Texas, 4–23 January 1917. He was released from military service at Fort Des Moines, Iowa, 20 February 1917, shortly before the United States entered World War I. A 1920 Air Service Information Circular listed Second Lieutenant Sanis E. Robbins as a pursuit pilot, residing at Cassia, Florida.
Robby Robbins married Miss Virginia J. Bing. They would have three children.
Robbins was commissioned as a Lieutenant Commander, United States Naval Reserve, 15 September 1940. He held this rank until at least 1955.
Captain Sanis E. Robbins died at Palo Alto, California, 8 August 1961, at the age of 62 years. He was buried at the Golden Gate National Cemetery, San Bruno, California.
Pan American Airways Boeing 314 NC18604, Atlantic Clipper, taking off. (NASM)
28 April 1937: The first transpacific flight by a commercial passenger airliner is completed when Pan American Airways’ Martin M-130, China Clipper, arrived at Hong Kong. The flight had departed San Francisco Bay, California, on 21 April with 7 revenue passengers and then proceeded across the Pacific Ocean by way of Hawaii, Midway Island, Wake Island, Guam, Manila, Macau, and finally Hong Kong. The Reuters news agency briefly reported the event:
