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Aichi M6A Seiran

Imperial Japan (1945)
Picture of Aichi M6A Seiran Submarine-Based Attack Floatplane Aircraft
Picture of Aichi M6A Seiran Submarine-Based Attack Floatplane Aircraft Picture of Aichi M6A Seiran Submarine-Based Attack Floatplane Aircraft
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The Aichi M6A-1 Seiran floatplane was to be housed and released from Japanese Navy I-400 class submarines.


Detailing the development and operational history of the Aichi M6A Seiran Submarine-Based Attack Floatplane Aircraft.  Entry last updated on 5/16/2018. Authored by Staff Writer. Content ©www.MilitaryFactory.com

This oft-forgotten Aichi aircraft design was classified as an attack floatplane, designed exclusively for the launching from Imperial Japanese Navy (IJN) I-400-class submarines. The IJN plan was to carry these aircraft in water-tight containers until arriving at a launch waypoint. The vessel would then surface, the aircraft readied, and then launched towards a target of opportunity. To help with storage aboard the submarine, the Aichi M6A Seiran ("Mountain Haze") was designed with wings that rotated and lay flat along the fuselage sides as well as tail surfaces that folded at their tips. Overall, the aircraft was largely conventional, featuring floatplanes for water-borne landings and a crew of two to spread the workload. Power was from an Aichi Atsuta Type 31 liquid-cooled V12 inline piston engine of 1,400 horsepower driving a three-blade propeller at front. Armed with a 13mm machine gun, the M6A was also to carry an offensive load of 1 x Type 91 torpedo or up to 1,875lbs of drop ordnance.

Aichi designed, developed, and produced their M6A series from 1943 to 1945 - the final year of the war. The type was being prepared for a surprise attack on the Panama Canal , a vital waterway for U.S. Naval operations in the Pacific. However, Allied advanced in the Pacific Theater, as well as the dropping of the two Atomic bombs on Japan forced an unconditional surrender for the Empire of Japan. As such, the aircraft did not see combat service in the war. Production was also disrupted due to the unrelenting Allied bombing campaign of the Japanese mainland which led to only 28 examples manufactured.

Eight base M6A1 prototypes preceded the eighteen M6A1 Seiran production models. A land-based derivative, known as the M6A1K "Seiran Kai", was intended for pilot and these would have been deployed with a wheeled undercarriage and of the tail-dragger arrangement for land-based service - losing the floatplane equipment. Only two prototypes were built. The M6A2 was a proposed platform that existed in a sole prototype - this outfitted with a Mitsubishi Kinsei MK8P 1,560 horsepower engine driving a constant speed propeller.

Performance specifications for the Seiran included a maximum speed of 295 miles per hour, a cruise speed of 185 miles per hour, a range of 740 miles and a service ceiling of 32,500 feet.

A sole, intact, Seiran floatplane aircraft is displayed by the Smithsonian National Air and Space Museum, Steven F. Udvar-Hazy Center in Washington, D.C. This aircraft represents the last production model completed. It was surrendered to U.S. occupation forces at the close of the war.


Picture of the Aichi M6A Seiran Submarine-Based Attack Floatplane Aircraft
Picture of the Aichi M6A Seiran Submarine-Based Attack Floatplane Aircraft



Any available statistics for the Aichi M6A Seiran Submarine-Based Attack Floatplane Aircraft are showcased in the areas immediately below. Categories include basic specifications covering country-of-origin, operational status, manufacture(s) and total quantitative production. Other qualities showcased are related to structural values (namely dimensions), installed power and standard day performance figures, installed or proposed armament and mission equipment (if any), global users (from A-to-Z) and series model variants (if any).






Our Data Modules allow for quick visual reference when comparing a single entry against contemporary designs. Areas covered include general ratings, speed assessments, and relative ranges based on distances between major cities.

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Relative Maximum Speed Rating
Hi: 300mph
Lo: 150mph
    This entry's maximum listed speed (295mph).

    Graph average of 225 miles-per-hour.
City-to-City Ranges
NYC
 
  LON
LON
 
  PAR
PAR
 
  BER
BER
 
  MOS
MOS
 
  TOK
TOK
 
  SYD
SYD
 
  LAX
LAX
 
  NYC
Graph showcases the Aichi M6A1 Seiran's operational range (on internal fuel) when compared to distances between major cities.
Aviation Era
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Pie graph section
Pie graph section
Pie graph section
Useful in showcasing the era cross-over of particular aircraft/aerospace designs.
Unit Production Comparison
Comm. Market HI*: 44,000 units
Military Market HI**: 36,183 units
28
28


  * Commercial Market High belongs to Cessna 172.

  ** Military Market High belongs to Ilyushin Il-2.


Altitude Visualization
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Origin: Imperial Japan
Year: 1945
Type: Submarine-Based Attack Floatplane Aircraft
Manufacturer(s): Aichi Kokuki KK - Imperial Japan
Production: 28
Status: Retired, Out-of-Service
Global Operators:
Imperial Japan
Historical Commitments / Honors:

Military lapel ribbon for Operation Allied Force
Military lapel ribbon for the Arab-Israeli War
Military lapel ribbon for the Battle of Britain
Military lapel ribbon for the Battle of Midway
Military lapel ribbon for the Berlin Airlift
Military lapel ribbon for the Chaco War
Military lapel ribbon for the Cold War
Military lapel ribbon for the Cuban Missile Crisis
Military lapel ribbon for the Falklands War
Military lapel ribbon for the French-Indochina War
Military lapel ribbon for the Golden Age of Flight
Military lapel ribbon for the 1991 Gulf War
Military lapel ribbon for the Indo-Pak Wars
Military lapel ribbon for the Iran-Iraq War
Military lapel ribbon for the Korean War
Military lapel ribbon for the 1982 Lebanon War
Military lapel ribbon for the Malayan Emergency
Military lapel ribbon for the attack on Pearl Harbor
Military lapel ribbon for the Six Day War
Military lapel ribbon for the Soviet-Afghan War
Military lapel ribbon for the Spanish Civil War
Military lapel ribbon for the Suez Crisis
Military lapel ribbon for the Vietnam War
Military lapel ribbon for Warsaw Pact of the Cold War-era
Military lapel ribbon for the WASP (WW2)
Military lapel ribbon for the World War 1
Military lapel ribbon for the World War 2
Military lapel ribbon for the Yom Kippur
* Ribbons not necessarily indicative of actual historical campaign ribbons. Ribbons are clickable to their respective campaigns/operations.
Measurements and Weights icon
Structural - Crew, Dimensions, and Weights:
Unless otherwise noted the presented statistics below pertain to the Aichi M6A1 Seiran model. Common measurements, and their respective conversions, are shown when possible.

Operational
CREW


Personnel
2


Dimension
LENGTH


Feet
34.88 ft


Meters
10.63 m


Dimension
WIDTH


Feet
40.22 ft


Meters
12.26 m


Dimension
HEIGHT


Feet
15.03 ft


Meters
4.58 m


Weight
EMPTY


Pounds
7,412 lb


Kilograms
3,362 kg


Weight
LOADED


Pounds
9,370 lb


Kilograms
4,250 kg

Engine icon
Installed Power - Standard Day Performance:
1 x Aichi Atsuta Type 31 liquid-cooled V12 inline piston engine developing 1,400 horsepower.

Performance
SPEED


Miles-per-Hour
295 mph


Kilometers-per-Hour
474 kph


Knots
256 kts


Performance
RANGE


Miles
1,243 mi


Kilometers
2,000 km


Nautical Miles
1,080 nm


Performance
CEILING


Feet
32,480 ft


Meters
9,900 m


Miles
6.15 mi


Performance
CLIMB RATE


Feet-per-Minute
1,640 ft/min


Meters-per-Minute
500 m/min

Supported Weapon Systems:

Graphical image of an aircraft medium machine gun
Graphical image of an aircraft aerial torpedo
Graphical image of an aircraft conventional drop bomb munition
Armament - Hardpoints (2):

STANDARD:
1 x 13mm Type 2 heavy machine gun

OPTIONAL:
2 x 551lb bombs OR 1 x 1,874lb bomb OR 1 x Torpedo
Variants: Series Model Variants
• M6A1 Prototype - Prototype
• M6A1 "Seiran" - Production Model Designation; 18 production aircraft.
• M6A1-K "Seiran Kai" - Trainer derivative of the base Seiran; never reached production status.
• M6A2 - Prototype Model; fitted with Mitsubishi Kinsei MK8P 62 at 1,560 horsepower; single production model.