During World War II, special large submarines were built in the Japanese Imperial Navy for transporting seaplanes. The seaplanes were stored folded in a special hangar inside the submarine.
Takeoff was carried out on the surface of the submarine; after the aircraft was withdrawn from the hangar and assembled for take-off on the deck in the bow of the submarine, special catapult runners of a shortened start were built, from which the seaplane rose into the sky. After the completion of the flight, the seaplane splashed down, and it was removed back to the sub's hangar.
Japan Projects
Project J-1M - "I-5" (with one reconnaissance seaplane, launch from water);
Project J-2 - "I-6" (one reconnaissance seaplane, launch from a catapult);
Project J-3 - "I-7", "I-8";
Project 29 type "B" - 20 units;
Type "B-2" - 6 units;
Type "B-3" - 3 units (the submarines had hangars, but they never carried aircraft - they were reequipped for "Kaiten", torpedoes operated by suicide pilots);
Project A-1 - 3 units (one reconnaissance seaplane, launch from a catapult);
Type I-400 - 3 units (3 Aichi M6A Seiran seaplanes);
AM type - 4 units (2 Seiran seaplane-bomber), 2 units not completed.
Seaplane bomber-torpedo bomber Aichi M6A Seiran
Creation began in 1942, the first flight took place in December 1943, entered service in 1944. The chief designer of the car is Norio Ozaki. A total of 28 units were built.
Basic performance characteristics:
Crew: 2 people;
Cruising speed: 300 km / h;
Max. speed at the ground: 430 km / h;
Max. speed at altitude: 475 (5200 m) km / h;
Flight range: 1200 km;
Service ceiling: 9900 m;
Length: 11.64 m;
Height: 4.58 m;
Wingspan: 12, 3 m;
Wing area: 27 m²;
Empty: 3300 kg;
Curb: 4040 kg;
Maximum takeoff weight: 4445 kg;
Engines: Aichi AE1P Atsuta 32;
Thrust (power): 1400 hp;
Small arms and cannon armament: 1x13-mm machine gun Type 2;
Number of suspension points: 3;
Suspended weapons: 2x250 kg or 1x800 kg or 1x850 kg torpedo;
Project Type I-400
Japanese submarines, designed in 1942-1943 as ultra-long-range submarine aircraft carriers for operations anywhere in the world, including off the coast of the United States. The submarines of the I-400 type were the largest among those built during the Second World War and remained so until the advent of nuclear submarines. According to the project, it was planned to build 16 submarines, in 1943 the plan was reduced to 9 submarines. They began to build 6 submarines, managed to build in 1944-1945. only three. They did not have time to visit the battle, after the surrender they were handed over to the United States, in 1946 they were flooded, since the USSR began to demand access to them.
Basic performance characteristics
Speed (surface) - 18, 75 knots;
Speed (underwater) - 6, 5 knots;
Maximum immersion depth - 100 m;
Navigation autonomy - 90 days, 69,500 km at 14 knots, 110 km underwater;
Crew - according to various sources, from 144 to 195 people, including 21 officers;
Surface displacement - 3,530 t standard, 5,223 t full;
Underwater displacement - 6 560 t;
Maximum length (at design waterline) -122 m;
Body width naib. - 12 m;
Average draft (at design waterline) - 7 m;
Power plant - diesel-electric, 4 diesels, 7,700 hp, 2 electric motors, 2,400 hp, 2 propeller shafts;
Armament: Artillery - 1 × 140-mm / 40, 10 × 25-mm Type 96, torpedo-mine armament - 8 bow 533-mm TA, 20 torpedoes;
Aviation - 3-4 seaplanes (one disassembled) Aichi M6A Seiran.
There is information that Japanese aircraft carriers were preparing for a retaliatory strike on the territory of the United States; after the atomic bombing of Japan, Tokyo was planning a biological attack. The submarines were supposed to go to the West Coast of the United States ("Operation PX"), and there the seaplanes-bombers were to strike at American cities, dropping containers with live rats and insects infected with the causative agents of bubonic plague, cholera, Dengue fever, typhoid, and other fatal diseases.
The possibility of an attack on the Panama Canal and an attack by American aircraft carriers in the parking lot at Ulithi Atoll (where the invasion forces on the Japanese Islands were concentrated) were also considered.
US aircraft carriers parked at Ulithy CV-18 Wasp, CV-10 Yorktown, CV-12 Hornet, CV-19 Hancock and CV-14 Ticonderoga, December 8, 1944.
On August 15, 1945, Japan surrendered, and on the same day, the submarine commanders were ordered to return to base in connection with the end of the war and to destroy all offensive weapons as top secret. The commander of the flagship boat I-401, Captain I Rank Arizumi, shot himself, and the team ejected the planes without pilots, without starting the engines. On the I-400, they did it easier - both planes and torpedoes were simply pushed into the water. Thus ended the history of the largest submarines of the Second World War, combining the most advanced technologies of the time and suicide pilots.
All "submarine aircraft carriers" were delivered for study to the US Navy base Pearl Harbor (Hawaii), and in May 1946 they were withdrawn to the sea and shot by torpedoes, since access to them was demanded by Soviet scientists.
The fact that Japanese submarines really could strike at the territory of the United States is proved by the incident that occurred in September 1942. When planes with Japanese insignia dropped several bombs on populated areas of the American state of Arizona, it caused a wave of panic among the population of the state. It was completely incomprehensible where the bombers came from, since the US Navy never, after Pearl Harbor, allowed Japanese aircraft carriers to approach American shores at a possible raid distance. As it turned out after the war, the bombers were launched from Japanese submarine aircraft carriers.
Until the end of the war, the Japanese were able to keep the "submarine aircraft carrier" program a secret.
Hangar on I-400.
