The Martin M-130 was a massive flying boat produced for the trans-Pacific route. Only three were built, and two were taken into US Naval service in 1942.
The M-130 was produced for Pan American Airways, who wanted an aircraft capable of operating a passenger service across the Pacific. Their route involved five stages, San Francisco to Honolulu to Midway to Wake Island to Guam to Manila. The first stage was the longest, at 2,410 miles and the shortest was still 1,260 miles long. The resulting aircraft was required to have a one way range of 2,500 miles carrying 12 passengers.
Martine built the M-130 in 1935. It was an all-metal flying boat with a high mounted wing that carried four engines. Retractable platforms were built into the wings to make it easier to service these engines, and two were replaced every three trips. It had a two-step hull, and sponsons were fitted at cabin floor level, sitting just above water level when the aircraft was on the water. These were used to help stabiles the aircraft on the water and carried half of its fuel.
There seems to be some confusion about the number of passengers that the aircraft could carry. They were built with three passenger lounges, each of which could carry six in a sleeper configuration, for a total of 18 people. The disagreements come over the number of seating passengers that could be carried, with figures of 24 (8 per cabin), 36 (12 per cabin) and 48 given (16 per cabin). The lower figure may have been accurate when the aircraft first entered service and the higher figures for when they were in military service, when the first class standards of peacetime would have been relaxed.
The China Clipper made the first ever commercial double crossing of the Pacific between 22 November and 6 December 1935 and regular flights between the US and the Philippines began on 21 October 1936. These flights took five days, of which 60 hours were spent in flight. The first aircraft was lost in 1938, but by 1940 the other two had flown an impressive 12,718,200 passenger miles.
China Clipper and Philippine Clipper were impressed into the US Navy in 1942 with the serial numbers 48230 and 48231, but they weren’t given a new naval designation. By 1942 standards they were somewhat under-powered (Martin had produced one example of the M-156, with four 1,000hp engines, in 1937). One was lost in a crash in January 1943 and the survivor must have been returned to Pan American by the start of 1945, when it was lost on a scheduled flight.
All three of the aircraft were lost in fatal crashes, and the number of passengers and crew on each occasion are known. The Hawaii Clipper disappeared in July 1938 while flying between Guam and Manila, with the loss of nine crew and six passengers!
The Philippine Clipper crashed into a mountain on 21 January 1943, with the loss of nine crew and ten passengers, while in military service. Sadly this crash took place at the very end of a trip from Honolulu to San Francisco, when the aircraft crashed into a mountain in California. Amongst the dead was Admiral Robert H. English, Commander, Submarines, United States Pacific Fleet.
The third aircraft, the China Clipper, was destroyed during a crash landing at Port of Spain, on 8 January 1945, after having been returned to Pan American service. It was carrying twelve crew and eighteen passengers, and nine crew and fourteen passengers were lost.
Engine: Four Pratt & Whitney R-1830 Twin Wasp engines
Power: 800hp each
Crew: Varied (included captain, first officer, radio-officer, flight engineer and steward at minimum)
Length: 90ft 10.5in
Height: 24ft 7in
Maximum Weight: 52,252lb
Maximum Speed: 180mph
Cruising Speed: 130mph
Range: 3,200 miles