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.
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 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.
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).
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 Samoan Clipper‘s number four engine on an earlier flight, a possible cause can be suggested.
On the earlier flight, the 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 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.
On the previous flight as fuel was being dumped, fuel vapors were present in the cabin, which required that all electrical systems to be shut off, even though it was night. Liquid gasoline was dripping into the cockpit from the wing above.
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.
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 flying boat had a useful load of 16,800 pounds (7,620 kilograms) and seats for 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). 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.
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.
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.
Pan Am personnel called the Clipper “Sweet Sixteen,” referring to her 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. It 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.
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 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).
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 the range was 3,200 miles (5,150 kilometers).
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.
Freighter S.S. 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.
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.
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.
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 flyjng 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).
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.
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.
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.
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.
29 July 1938: At 12:08 p.m., local time, the Pan American Airways flying boat Hawaii Clipper lifted off from the waters of Apra Harbor on the west side of Guam, an island in the western Pacific Ocean. The Clipper was on a planned 12½ hour flight to Manila in the Philippine Islands. On board were a crew of nine, with six passengers.
Hawaii Clipper never arrived at its destination. What happened to it and the fifteen persons on board remains one of the enduring mysteries of aviation history.
The flight was designated Trip #229. It had originated at Alameda, on San Francisco Bay, California, and flew to Honolulu in the Hawaiian Islands, then on to Midway Island, Wake Island, and Guam.
The Pan Am crew consisted of Captain Leo Terletzky, First Officer Mark A. Walker, Second Officer George M. Davis, Third Officer Jose M. Sauceda, Fourth Officer John W. Jewett, Engineer Officer Howard l. Cox, Assistant Engineer Officer T.B. Tatum, and Radio Officer William McGarty. The passengers were attended by Flight Steward Ivan Parker.
Captain Terletzky held a Transport Pilot’s License issued by the Aeronautics Branch of the United States Department of Commerce. He had flown more that 9,200 hours, and 1,614 hours in the Martin M-130.
Captain Terletzky (there are alternate spellings, such as Terletsky, and he was also known as Leo Terlitz) was born 18 January 1894 at Odessa, Imperial Russia (now, Ukraine).
Following the Russian Revolution, he left his native country and traveled to Omsk, Siberia, and then to Yokohama, Japan, where he embarked on S.S. Empress of Japan, on 28 March 1919. The passenger liner arrived at Vancouver, British Columbia, Canada, 6 April. He then traveled on to Seattle, Washington, via the Canadian Pacific Railroad, arriving there on 9 April 1919.
Terletzky became a naturalized citizen of the United States, 15 December 1924. On 1 July 1919, he married Miss Helen Sarepta Bowman at Miami Beach, Florida.
The airliner’s six passengers were: Lieutenant Commander Edward E. Wyman, United States Naval Reserve, of Bronxville, New York. Commander Wyman was the former assistant to Juan Trippe, the founder of Pan American Airways. He was now employed by Curtiss-Wright. Pan American’s traffic manager, Kenneth A. Kennedy, was also on board. Colonel Earl E. McKinley, M.D., United States Army Reserve, Dean of Medicine at George Washington University in Washington, D.C., a bacteriologist, and Fred C. Meier, Ph.D., were collecting airborne bacteriological samples to research transocean bacterial transfer. Major Howard C. French, Air Corps, United States Army (Reserve), the commanding officer of the 321st Observer Squadron based at Vancouver, Washington. Finally, there was Choy Wah Sun (also known as “Watson Choy”), of New Jersey. Mr. Choy was believed to be transporting $3,000,000 in U.S. Gold Certificates for the Kuomintang, the Nationalist Party of China, which was headed by Chiang Kai-shek.
Hawaii Clipper was a Martin M-130, NC14714. It was the first of three of the type built for Pan American Airways. With the experimental registration NX14714, it had made its first flight at Middle River, Maryland, 30 December 1934.
When Hawaii Clipper departed Alameda, it had flown 4,751:55 hours, TTAF. When it made its last position report, it had flown another 55 hours, 58 minutes.
The Martin M-130 was a large, four-engine flying boat of all-metal construction, designed to carry as many as 36 passengers on transoceanic flights. The 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 flying boat had a maximum takeoff weight of 52,252 pounds (23,701 kilograms).
The M-130 was powered by four air-cooled, supercharged Pratt & Whitney Twin Wasp S2A5-G two-row 14-cylinder radial engines with a compression ratio of 6.5:1. The S2A5-G had a Normal Power rating of 830 horsepower at 2,400 r.p.m. to 3,600 feet (1,097 meters), and 950 horsepower at 2,550 r.p.m. for takeoff, using 87-octane gasoline. The engines drove three-bladed Hamilton Standard Hydromatic constant-speed propellers through a 3:2 gear reduction. The S2A5-G was 4 feet, 8.75 inches (1.442 meters) long, 3 feet, 11.88 inches (1.216 meters) in diameter, and 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). Its range was 3,200 miles (5,150 kilometers).
Hawaii Clipper departed its mooring at Apra Harbor at 11:39 a.m., local time (3:39 a.m., Manila time) and lifted off 29 minutes later. In addition to its six passengers, the airliner was carrying 1,138 pounds (516 kilograms) of cargo. The duration of the flight was estimated as 12 hours, 30 minutes. The M-130 carried sufficient fuel for 17 hours, 30 minutes of flight. Its gross weight was 49,894 pounds (22,632 kilograms) at takeoff, well under its maximum takeoff weight.
At 04:11 Greenwich Civil Time (12:11 p.m., local time), Radio Officer McGarty sent Hawaii Clipper‘s coded 04:00 Ded Reckoning ² position report. The deciphered message read:
“Flying in rough air at 9,100 feet. Temperature 13 ˚C., wind 19 knots from 247˚ Position N. 12˚27, E 130˚40, ground speed made good, 112 knots, desired track 282˚. Rain. During past hour conditions varied. 10/10ths sky above covered by strato cumulus clouds, base 9,200 feet. Clouds below 10/10ths sky covered by cumulus clouds whose tops were 9,200 feet. 5/10ths of the hour on instruments. Last DF bearing from Manila 101˚”
This placed the Clipper approximately 582 nautical miles (670 kilometers) east southeast of Manila. The transmission was acknowledged. When the land-based radio operator tried to make contact one minute later to provide updated weather information, he received no reply. There were no further radio transmissions received.
When Hawaii Clipper did not arrive at Manila, a large ocean search was begun. On 30 July, the Unites States Army transport ship USAT Meigs discovered an oil slick approximately 28 nautical miles (52 kilometers) south southeast of the flying boat’s last reported position. The slick was described as being approximately 1,500 feet (457 meters) in circumference.
No physical evidence of the Martin M-130 has ever been found. What happened to cause its disappearance is unknown.
While it is assumed that the airplane went down at sea, that might not have been the case.
A telephone company employee on Lahuy Island (a small island of the coast of Luzon, east southeast of Manila) reported having heard a large airplane above clouds at 3 p.m. Manila Time. In 1938, the number of large airplanes operating in the Philippine Islands must have been fairly limited.
As with the disappearance of Amelia Earhart and Fred Noonan the previous year, there was no shortage of “conspiracy theories.” An example is that agents of the Empire of Japan had stowed away aboard Hawaii Clipper, hijacked the airplane and it was flown to Ulithi, and then Truk. The story goes on the the passengers and crew were murdered and their bodies were buried under the foundation of a hospital under construction.
Another story is that the Clipper was intercepted by a Japanese flying boat, such as the Kawanishi H6K Type 97 Large Flying Boat, which forced it to an unknown destination, similar to the story above.
Only six months earlier, another Pan American flying boat, Samoan Clipper, a Sikorsky S-42B, NC16734, disappeared about two hours out of Pago Pago. The airliner is believed to have exploded in midair. In that case, an oil slick and wreckage were found.
¹ Following the United States’ entry into World War II, Captain Terletzky’s widow, Mrs. Sarepta B. Terletzky, (née Helen Sarepta Bowman), a graduate of Smith College, joined the United States Navy. She was commissioned as a Lieutenant, W-VS, United States Naval Reserve, 4 August 1942. On 1 December 1945, she was promoted to the rank of lieutenant commander, and to commander, 1 January 1950. Mrs. Terletzky had been born at New York City, New York, 28 September 1895. She died at Miami, Florida, 4 August 1970.
² Ded Reckoning (Deductive Reckoning, often erroneously referred to as “dead reckoning,” is a method of navigation which uses a previously known position, time of flight, estimated speed of the aircraft based on forecast weather conditions, etc., to estimate the current geographical position. It is the standard method of navigation in the absence of radio aids or satellite position.