From the Sea to the Moon
Twenty-three-year-old Lieutenant Thomas O. Paine boarded the giant Japanese submarine with some trepidation. It was September 1945, and Japan had surrendered just days earlier. “I recall my mixed emotions as we pulled alongside her towering hull and scrambled…onto her foredeck,” he wrote in an unpublished memoir. “I was excited to be carrying out a classic naval Boarders Away! operation, wary of the impassive Japanese who stiffly greeted us, curious about the unfamiliar aircraft handling equipment around us, delighted to be directly involved in this historic finale of the undersea war, and concerned about both the technical and human problems involved in carrying out our orders….”
The submarine Lieutenant Paine and his detail boarded belonged to the I-400 class, the largest subs of World War II. They were specifically designed to carry and launch the new Aichi M6A1 Seiran floatplane bomber, with the goal of attacking major U.S. cities or the Panama Canal to disrupt America’s advance across the Pacific. A more sinister mission—unleashing biological weapons on the U.S.—was seriously considered but later rejected.
In these times of heightened homeland security awareness, it’s interesting to contemplate the “what ifs” surrounding Japan’s very real plans to attack the United States. Although organized too late in the war, an I-400–class sub mission to bomb the Panama Canal using Seirans painted in U.S. Army Air Forces markings came within a few weeks of being pulled off. But with America marshaling its forces to invade the Home Islands, Japanese strategists instead decided to use the I-400s to attack U.S. Navy ships at Ulithi Atoll, and the canal mission was canceled. When Japan surrendered before the super subs could reach Ulithi, the I-400s fell into Navy hands.
John Geoghegan tells the fascinating, largely overlooked story of these underwater aircraft carriers and their sleek Seiran bombers beginning on P. 34. Geoghegan traveled to Japan to conduct research and interviews with the chief pilot of Seiran Squadron 1, as well as I-401’s captain and chief navigator. His account is complemented in this issue by Dick Smith’s “Modeling” column (P. 43) and “Restored” article (P. 58), about the National Air and Space Museum’s restoration of the last surviving Seiran.
After getting his first look at an I-400 sub, Lieutenant Paine went on to serve as executive officer and navigator of the Navy prize crew that sailed I-400 from occupied Japan to Pearl Harbor—a “fitting finale to my career in the Submarine Service,” he wrote. Also sailing to Pearl were I-401 and I-14, the latter under Commander John S. McCain Jr., father of the future Arizona senator. Back at Pearl, Paine gave tours of the giant subs to visiting military officials. “We liked to astonish visitors by majestically opening…our cavernous hangar or by raising and lowering our towering 12-ton seaplane derrick. To entertain top brass we fired our noisy pneumatic catapult. Our crew took pride in our mastery of this remarkable submarine.”
After the war, Paine worked as a researcher at Stanford University, the General Electric Research Laboratory and GE Center for Advanced Studies. He would eventually serve as administrator of NASA during the first seven Apollo manned space missions—quite a career change for a former submariner. In one of those delicious twists of history, while at NASA he worked with “Junior” McCain again. “He was commander Pacific, providing carrier support for the splashdown of Apollo astronauts returning from the moon. While he smoked his famous long, black cigars we chuckled over the irony of two old I-boat sailors working together on interplanetary transport!”
Paine made another connection between his Navy and NASA service: The gold dolphins that he had worn in the Submarine Service and while aboard I-400 went to the moon with Neil Armstrong in July 1969. You can read more of his memoir at www.pacerfarm.org/i-400.
Originally published in the May 2008 issue of Aviation History. To subscribe, click here.