As war with America became a distinct possibility in the late 1930s, Japan began to strengthen its submarine fleet for long range engagements against far off American targets. One avenue it energetically pursued in these pre-radar days was carrying a small seaplane in waterproof hangers on submarines for long range reconnaissance.
In 1938 Japan’s First Naval Technical Arsenal presented Japanese aircraft manufacturers with a design for such a submarine-based seaplane to meet this requirement. The Yokusuka company took up the design and in 1939 produced a small, two seat monoplane seaplane, the E14W1, powered by a 340 horsepower air cooled radial engine.
The E14W1 was only 28 feet long and had a wingspan of 36 feet and was designed to be easily dismantled for storage in a submarine’s hangar. The top of the vertical tail and the twin floats and supporting struts detached from the fuselage and the wings were removed from the fuselage at the spar fittings, then the aircraft fuselage was fitted into a cylindrical hanger behind the submarine gunning tower. The floats and flying surfaces were then placed on the sides of the hanger.
The E14W1 was selected for production and named the Navy Type O Submarine-borne Reconnaissance Seaplane Model 1-1, but given the code name “Glen” by the Allies.
When the war started, the Glens were quickly pushed into action, and one, launched by the Japanese submarine I-11, successfully performed a damage assessment flight over Pearl Harbor on Dec. 17, 1941 — 10 days after the Japanese attack.
But the Glen’s true moment in aviation history came on the morning of Sept. 9, 1942, when the Japanese submarine I-25, having conducted four successful missions using the Glen, arrived off the Oregon cost.
The I-25, which had barely escaped being hit in dry dock by Doolittle’s Tokyo raid in April 1942, launched a Glen carrying two 170 pound incendiary bombs toward the Oregon forest region, and the Glen dropped the bombs a few miles outside Brookings, Ore.
However, two rangers heard the incoming Glen — one noted it sounded like a Model-T backfiring — and saw the smoke plume from the fire started by the bombs. The rangers reported the fire and hiked to the area where they put out the fire, helped by light winds and wet weather.
Shortly after the Glen landed and was loaded back into the hanger, the I-25 was attacked by American aircraft, but escaped. Nevertheless, it stayed in the area and launched a second bombing raid on Sept. 29, 1942. The Glen was launched in pre-dawn darkness using the Cape Blanco, Ore., lighthouse as a reference. But, though the plane was again heard by forest rangers, no fires were started by bombs.
The Glen attacks were the first, and only, time the continental U.S. was bombed by an enemy aircraft. Radar made any more raids like this impractical, but Glens continued to serve in the Pacific for another year. The small aircraft did have a serious disadvantage because it could only be launched and recovered in calm seas, and as the American anti-submarine forces, aided by code breakers, became more aggressive and there were few opportunities for the Glen to be useful.
However, the Japanese did not drop the idea and toward the end of the war converted several large submarines to seaplane carriers to carry much larger attack aircraft for a raid on the Panama Canal, but the war ended before the operation could be carried out.
Ironically, 20 years later, Glen pilot Nobuo Fujita was invited back to Brookings, Ore., where he served as grand marshal for the local Azalea Festival.
(Dr. Michel’s articles appear twice a month in the KA. For questions or comments, e-mail Dr. Michel at email@example.com.)