In-Box Review
IJN I-400 Sub
IJN I-400 Submarine(2 included)
  • Box Art

by: Anthony Kochevar [ AJKOCHEV ]

The Boat...

The I-400 class submarines were the largest subs built during World War II and were actually the largest built until the 1960’s. The carried three aircraft in a special hanger mounted on top of the hull. They held enough fuel to travel one and a half ways round the world. They could have attacked the United States from either coast, east or west.

Construction began in 1943 with 18 boats originally planned. Soon afterward the plans were scaled back to 5 boats, of which only 3 were completed. The submarines were planning an attack on the Panama Canal from the eastern Caribbean. The attack was in the advanced planning stages when word of the Allied attacks on Japan reached the Japanese base at Maizuru.

The attack was then shifted to the Allied base at Ulithi. Plans were made for this attack, but were never carried out. The submarines were out to sea when Japan surrendered. On August 22 1945 the crews were ordered to destroy all their weapons. All torpedoes and aircraft were disposed of. All three submarines were surrendered to the American Navy.

The USN examined the subs and eventually scuttled all three. It is rumored the I-400 class was the source for the Soviet Typhoon class and gave the American’s the idea to launch missiles from a submarine. However since the Soviets never did examine the I-400 boats this is highly doubtful. The I-400 class was a large step forward in submarine design.


Displacement: 5,223 tons, 6,560 tons (Full Load)

Length: 122 m (400 ft)

Beam: 12.0 m (39 ft)

Beam: 12.0 m (39 ft)

Propulsion: 4 diesels: 7,700 hp (5.7 MW), surface Electric motors: 2,400 hp (1.8 MW), submerged

Speed: 18.75 knots (35 km/h), surfaced 6.5 knots (12 km/h), submerged

Range: 37,500 nmi. at 14 knots

Test depth: 100 m (330 ft)

Complement: 144

• 3 Aichi M6A1 Seiran sea-planes
• 8 × 533 mm forward torpedo tubes
• 1 × 140 mm (5.51 in) 40 caliber gun
• 3 × 25 mm 3-barrel machine gun
• 1 × 25 mm machine gun

The Kit...

The box art has been done really well. The back of the box has the painting instructions. Upon opening the kit I found the instruction sheet and one bag containing the two A and one B fret and the decals. No loose pieces where seen in the bag and all frets were undamaged.

Fret A

This fret has the sub hull, deck, tower and a few other details. The deck really stands out. It is loaded with small details and is incredible. The only downside to it is the crane and rear mast are molded in there respective slots like they are put away. They provide the erected ones, but it would of been nice if the manufacturer could of provided these folded ones as separate optional pieces.

The hull looks really good to and the choice of building ether as a waterline or full hull is a big plus.

The tower and other details have small drain holes molded into the plastic at a reasonable scale size, leaving you with the impression that this is a resin kit. The airplane hanger can be model ether open or closed.

Fret B

This set includes the guns, planes, cranes and stands for the kit. There are enough guns for both submarines and they are very highly detailed. The fret only has three planes total and since each sub carried three planes, you will be short a few if you want them all displayed on the outside. The fret includes airplane landing gear(can be float or standard) and propellers, but slightly overscale. There are two stands included for if you build both as full hull.

The set looks really good and contains all the painted flag/marking decals the subs have. This set must come with all the pit-road IJN subs as it includes decals for all the submarines in there line.


Building of the sub is well diagramed fortunately. Other than a small snipit about the history of the sub, the entire instructions are in Japanese. It even diagrams making some scratchbuilt internal hangar components and how to display a plane in the folded position.


All in all a really good kit in case you don't want to go the 1:350 route with other manufacturers. About the only issue you will have with this kit is finding it as Pit-Road stuff can be hard to come by.
Highs: High Detail; Waterline or Fullhull Option; Two Subs Included
Lows: Short on Planes; Some Overscale Pieces; Availiblity
Verdict: A great kit to build you a couple of I-400 type submarines, if you can get your hands on it.
Percentage Rating
  Scale: 1:700
  Mfg. ID: W48
  PUBLISHED: Oct 30, 2008
  NATIONALITY: Japan / 日本

About Anthony Kochevar (ajkochev)

I've modeled ships as a teen and started the hobby again in 2005. For some reason I got into the history of the Japanese Navy at this time and started building ships of this navy. I also do N Scale model railroading, reef aquariums and a few video games.

Copyright ©2021 text by Anthony Kochevar [ AJKOCHEV ]. Images also by copyright holder unless otherwise noted. Opinions expressed are those of the author(s) and not necessarily those of Model Shipwrights. All rights reserved.


Click image to enlarge
  • Box Art
  • Box bottom w/ painting info
  • Kit insides
  • Rev005
  • Weapons
  • Rev007
  • Conning tower detail
  • Aircraft
  • Rev011
  • Rev012
  • Catapult Details
  • Decals
  • Instruction sheet