Bombing of America

[Bullockracing]

Originally Posted by Twitch

This plane dropped 2 bombs into an Oregon forest in September 1942. The Yokosuka E14y1 (Glen) was a submarine-launched floatplane catapulted from the deck. I'm too lazy to look up which Japanese I-boat number did it, but rest assured it was done.

I thought that attack was carried out against US territory around the Panama Canal?

[Twitch]

Ok, looked it up. It was the I-25 that launched the floatplane that bombed Oregon.

Here's a segment of an article I did regarding the Panama Canal deal:

The Sen-Toku class I-400 was built as the largest submarine class in the world in 1943 in Kure Navy Yard. This new class was designed to carry three two-seat Aichi M6A1 Seiran (Mountain Haze) floatplane torpedo-bombers capable of carrying either two 550-lb bombs or a 1,760-lb. torpedo at a range of 739 miles.

During her construction the idea was born to use the Sen-Tokus to launch a surprise air attacks against the Panama Canal's Gatun Locks. The plan was to assign ten Seirans to strike the Locks with six torpedoes and four bombs. Destroying these locks would empty Gatun Lake and block the passage of shipping for months it was thought.

On December 30, 1944 when the I-400 was launched the attack on the Panama Canal had been shelved due to the large B-29 fire bomb raids on Tokyo. Revenge would now be had with an operation against San Francisco no less, putting I-15’s earlier recon to use. During the I-400’s construction several I-13 class boats were modified to carry two aircraft.

The Sen Toku class was large, being about half again as large as America fleet boats. The I-401 and I-402 followed. I-404 and I-405 were under construction at war’s end with the 404 being 90% complete. Thirteen more of the big boats were planned. They displaced 6,560 tons submerged and were 400 feet long. No submarine was larger until the American nuclear subs put to sea in the 1960s.

Four diesels with a combined power of 7,700 HP were augmented by four electrics with 2,400 combined horsepower for underwater activity. The big subs had snorkels in the style of U-boats too allowing use of the diesels while submerged. Surface speeds of 18.75 knots could be attained while 6.5 knots was maximum speed submerged. Fuel bunkers carried sufficient fuel for 37,500 nautical miles at 14 knots!

Maximum dive depth was shallow compared to U-boats at 330 feet. Ten 25 mm cannon served as AA weaponry while twenty 533mm torpedoes would launch from eight forward tubes. One 140mm deck gun was mounted. Crew compliment was 144 officers and men.

The three 38-foot long Seirans rode in a 115-foot cylindrical hanger nose to tail during transport to target area. Assembly was accomplished in just six minutes. The assembly crews were aided in low light conditions with fluorescent paint on key parts. Wingspan assembled measured 40 feet with normal weight at 9,370 lbs.

A catapult on the forward deck could launch the planes either with or without their floats. One way missions would require no floats. A 1,400 HP Atsuta 32 inverted V-12 liquid-cooled gave good performance. Top speed of the Seiran was 295 MPH at 17,060 feet with floats and 360 MPH without. The ceiling of 32,480 feet was rather high. It was close in performance and looks to the rugged Aichi D4Y dive bomber with the same power plant.

Twenty M6A1s were made including several float-less trainers called the Nanzan (Southern Mountain) with retracting landing gear. Gun armament for all was a single 12.7 mm in the rear cockpit for defense.

The ever-changing course of the war saw the I-400 class boats attack plans change with it. No Panama Canal or San Francisco forays were attempted. The Ulithi Harbor at Truk Island was earmarked in an operation with I-401 plus I-13 and I-14 carrying their swift Nakajima C6N1 Saiun (Myrt) long range reconnaissance aircraft. The Myrts would recon the harbor and report to I-400 and I-401. Not having floats we must surmise that they were to be ditched.

The attack was set for August 17th under a full moon. The Seirans were to each carry bombs for the attack then return and land near their submarines. After the attack, all four I-boats were to proceed to Singapore for fuel and take on new planes for the attack. Ten Seirans were to be stationed there prior to the attack on Ulithi. Their markings were to be changed to American ones to aid in their camouflage for a surprise factor.

Before the operation played out the war was over and the big boats were surrendered to the Americans. All three completed Sen-Tokus survived the war. They were later evaluated then sunk in target practice in mid 1946. They were unique to history. No other WW II nation had any sub with an aircraft aboard.

[DerAdlerIstGelandet]

Intersting thanks for the info.