Mitsubishi 12th Experimental Carrier-Based Fighter [A6M1] : Origin of the Legend

[aizenns 3,591]

Mitsubishi Heavy Industries

12th Experimental Carrier-Based Fighter

十二試艦上戦闘機

A6M1

A6M1, transported from the factory to the airfield by oxcart

 

History

In 1937, IJN ordered next gen fighter, 12th Experimental Carrier-Based Fighter to Mitsubishi and Nakajima. Request content was as follows:

• Max speed should be over 270 kt at 4,000 m
• Climb time to 3,000 m should be less than 3 min 30 sec
• Cruise range at normal loads with full power should be over 1.2 hours, and cruise range at over loads with full power should be over 1.5 hours
• Air combat performance should not inferior to Type 96 Mark 2 Carrier-Based Fighter Model 1 (=A5M2a)
• Takeoff and landing should be easy, take off distance at wind speed 12 m/s should be less than 70 m, and landing speed should be less than 12 m/s
• Weapon should be 2x 20 mm MG and 2x 7.7 mm MG
• Radio equipment should be Courcy aviation mark 3 radio return direction measuring instrument (クルシー式空三号無線帰投方位測定器) and Type 96 aviation mark 1 wireless phone

This aircraft designed by Horikoshi Eichiro and several veteran engineers. On the other hand, Nakajima retired to this competition before build mockup.

 

To achieve requirements, design greatly progressed from A5M: using constant-speed propeller, retractable leg and tail wheel, streamlined closed canopy, new 20 mm machine gun and new material Extra Duralumin Steel.

Also, to decrease air resistance, they devised the design. For example, they adopted flush rivets used since G3M for overall.

 

First prototype of A6M1 completed in March 16, 1939 and made the first flight in April 1. They built at Mitsubishi Heavy Industries Oe factory at Nagoya, but that factory did not have airfield so they need to transport them to Kakamigahara airfield but trains cannot load such a large cargo (It cannot path through the tunnel), and if use the trucks, vibration by narrow bad road will destroy the plane. Because of it, they chose primitive way: slow oxcart.

In the test flight, performance of the A6M1 was excellent. To resolve vibration problem, they replace 2-wing propeller to 3-wing propeller, and since prototype #3 they replaced the engine to powerful Sakae model 12 (A6M2)

Finally, the A6N with new engine, A6M2 was adopted and named "Type 0 Mark 1 Carrier-Based Fighter" aka "Zero-sen".

 

Difference between A6M1 and A6M2

Engine: A6M1 had Zuisei model 13, but A6M2 had Sakae model 12

Propeller: A6M1 had 2-wing propeller, but A6M2 had 3-wing propeller

Spinner: A6M1 did not had spinner, but A6M2 had it.

Cowling: Shape is different by the engine difference

Body: Rear body of A6M1 is 40 cm shorter than A6M2

Horizontal stabilizer: Horizontal stabilizer of A6M1 is placed 16 cm down than A6M2

Vertical stabilizer: Area of vertical stabilizer of A6M1 is smaller and placed on 40 cm forward than A6M2.

Paint color: A6M1 painted with greenish gray, but A6M2 painted with gray.

 

Specification

• Engine: Zuisei model 13
  • Takeoff: 780 HP
  • Standard: 875 HP at 3,600 m
• Propeller: 2-wing constant speed metal propeller
• Fuel loads: 518 l
• Width: 12.00 m
• Length: 8.79 m
• Height: 3.49 m
• Wing area: 22.438 m2
• Own weight: 1,652 kg
• Loads: 691 kg
• Full-load weight: 2,343 kg
• Wing loads: 104 kg/m2
• Weight to power ratio: 2.68 kg/HP
• Max speed: 275 kt (509.3 km/h) at 3,600 m
• Landing speed: 60 kt
• Climb rate: 5,000 m at 7 min 15 sec
• Weapon
  • Nose
    • 2x Type 92 7.7 mm machine gun
  • Wing
    • 2x Type 99 Mark 1 20 mm machine gun
  • Wing pylons
    • 2x No.3 Common Bomb Model 2
    • 2x Type 99 No.6 Common Bomb Model 1

 

Pros & Cons

Pros

• Excellent Mobility
• Powerful 20 mm machine gun

Cons

• Slower than A6M2
• Poor protection

 

For War Thunder

For game, it will be very interesting addition for A6M family! The "first prototype of the Zero" sounds like good addition for the premium. Also, if add A6M1 for premium it will be good support for beginner players.

 

Photos

Under construction

Spoiler

Replica

Spoiler

A6M1 (replica) and Ki-61-II Kai (original)

 

Reference

野沢正 (1981) ｢日本航空機総集　三菱篇｣ 出版協同社 pp.186-193

EN: Nozawa Masashi (1981) "Encyclopedia of Japanese Aircraft, part 1, Mitsubishi" Shuppan-Kyodo-Sha, pp.180-183

ASIN B000J7WXCC

 

Gifu-Kakamigahara Air and Space Museum

http://www.sorahaku.net/1000842/1000844/1000846.html

 

http://www.city.kakamigahara.lg.jp/webmagagine/6874/24752/025038.html

https://www.jiji.com/jc/d4?p=zft812&d=d4_mili

http://noukakuken.jp/lecture/lec1505.html

 

[leroyonly 4,311]

Open for discussion. 

[Milocat 4,857]

+1, the first zero sounds like a lot of fun to take out for a spin.

[Solarmod 1,204]

Sounds neat. +1

[stuka2689 314]

+1, looks like good low tier turn fighter.

[Spindash64 1,244]

Yo dawg, I heard you like Zeros, so here's a Zero V0 so you can Zero in with your Zero while you Zero

 

+1

[Fireraid233 4,274]

Could be a nice low tier premium +1

[Z3r0_ 4,128]

Could be fun as a premium.  Just keep in mind that the original A6M1 was badly underpowered, so it won't just be slower than the A6M2, it'll be worse in almost every way performance-wise.

[Norris_Aznable 35]

While I'd never spend a cent on Premium vehicles, I think this would make a really good early premium for the Japanese tree. It's more forgiving than having people having a taste of the Zero with the A6M5 Ko, which is at a BR where Zero's abilities are less effective.

[JPAU401 37]

+1 for a wonderful and significant piece of history!

[Tetravault 225]

+1 Need some more of these kinds of origin aircraft in-game

[CokeSpray 7,274]

Suggestion passed to the developers for consideration.