Nakajima Aircraft was established by Nakajima Chikuhei in Gunma of Japan in 1917. Nakajima flew test flight in the Tone River at first. Nakajima began to make autos after the Pacific War. Nakajima Chikuhei became a minister of Muitions after surrender of the Pacific War. Nakajima changed its name Fuji. The brand is SUBARU. Sales of autos in Japan decreases now. Fuji announced that it would accept Toyota's capital of 17% share in Apr 2008. By the way, Hasegawa Tatsuo, a chief engineer of Toyota Corolla was an engineer of Tachikawa Aircraft.
Ministry of Munitions
Hasegawa Tatsuo(1916-2008)

1. Production of fighters
   

   Production of fighters and makers 1937-1945

   Name	Engine	Nakajima	Mitsubishi	Kawasaki	Kawanishi	Tachikawa	Arsenal	Sum
   Claude	Kotobuki	-	782	-	-	-	200	982
   Nate	Ha-12	2,007	-	-	-	1,379	-	3,386
   Zero	Sakae	6,545	3,880	-	-	-	-	10,425
   Oscar	Ha-25	3,208	-	-	-	2,545	-	5,753
   Tojo	Ha-41	1,227	-	-	-	-	-	1,227
   Hamp	-	327	-	-	-	-	-	327
   Tony	Ha-40	-	-	3,159	-	-	-	3,159
   Frank	Ha-45	3,449	-	-	-	-	-	3,449
   Jack	Kasei	-	470	-	-	-	-	470
   Shiden	Ha-45	-	-	-	1,000	-	-	1,000
   Geroge	Ha-45	-	-	-	400	-	-	400
   Production of makers		16,763	5,132	3,159	1,400	3,924	200	30,578
   Ratio of makers		54.8	16.8	10.3	4.6	12.8	0.7	100%

   Japan made 30,000 fighters in WWII. The table shows production of fighters of makers in Japan in 1937-1945. Nakajima made more than half of them and 3 times of Mitsubishi.
   Aoki p.33

   The tables did not conclude seaplane fighters of Kawanishi. The production of Rex(Kyoufu) was 97. And another important fighter was Ki-100 of Kawasaki. The production was 397.
   Rex(Kyoufu)
   Ki-100

2. Production of engines
   Nakajima bougt manufacturing license of Cyclone R-1820F engine from Wright of US in 1933. Nakajima also bought a lot of casting machines, when a shop foreman went to learn manufacturing engines at Wright.
   Ikari p.200

   Nakajima made 88% of engines loaded on fighters of Japan. These were Kotobuki(Clade, Nate), Sakae(Oscar, Zero), Ha-109(Tojo), Homare(Frank, Shiden, George). Nakajima won sales of 2,000hp class aircraft engines between competitor Mitsubishi. While Mitsubishi made more than half of bombers engines. Itogawa Hideo was an engineer of Nakajima.
   Aoki p.37
   Kessaku-ki no tanjyou
   Itokawa Hideo

   Director of IJA ministry Nagata Tetsuzan thought that IJA air force was old and a demand of ¥200 million budget for aircraft and air defend in 1934 or 1935.

3. Factory evacuation
   

   Production of Nakajima

   Year	1942	1943	1944
   Production	2,215	4,646	7,896

   Nakajima Aircraft planned to build underground factories in 1942. It began to build them at Ouya in 1945 where was area of stone production and located in the northern Kanto. The underground factory was to make 300 aircraft a month. It was 56,435 m2 area, 5,702 workers. But it made 11 engines, 55 repairs of engines and 4 aircraft only for 4 months till end of the war. Production of Nakajimas slowed down because of threat of air raids before acutual B-29s bombardment.

4. Defense engine plants
   B-29 tried bombardment at Musashino Factory on 24 November 1944 for the first time. Carriers aircraft of US burned an engine assembly of Nakajima Musashino Factory on 17th Feb 1945, though B-29 tried to destroy it called #357 target. Helldivers and Avengers flew 200km the south east off the Tokyo Bay and raided accurate bombardment. They used rockets too. New York Times told the story and praised USN. B-29 bombed there on 2th, 7th and 12th Apr 1945. At last Musahino Factory stopped the production on 30th Apr 1945.
   Kerr, p116-117
   Watanabe, p314
   Morimoto, p254

   I think the raid was easier than charge of running warships suppored AA guns, if escort fighters got the air control. How about flaks of Nakajima Mushashino?

5. Productivity
   

   Productivity per std labor[lb]

   Date	USA	Japan	Germany
   1941Jul	1.42	0.63	1.15
   1943Jul	1.88	0.71	1.50
   1944Jul	2.76	0.71	1.25

   US succeeded in increase of aircraft productivity during WWII. Japan's productivity did not increase. I think innovation occurred in US during the WWII. Japanese aircraft industry did not have knowledge to use a lot of jig and could not prepare machine tools such a special lathe.
   Hinkoku, p71

IJN also fought with I-16 in China, otherwise Fighters of IJN did not equipped armor or self-sealed tank. IJA thought cool that it was diffcult to grow pilots in a short time than IJN. IJN realized armor of fighters in the air battle of Solomons. Zero equipped in 1944 as the table shows. As for bombers, Betty eqipped armor plates and self-sealed tanks in 1943. While B-17 had been already equipped with both in 1941.
Betty

Genda insisted the necessity in his report about Battle of Britain in fall of 1940. Genda p.238

Is it true?

Wing load of US and Japanese fighters

Name	F4F	F6F-3	F4U	P-51A	P-51D	A6M2b	A6M5a	J2M2	N1K2-J	Ki-84
Date	1939Feb	1941Jun	1939Oct	1940Oct	1944Apr	1939Mar	1943Sep	1942Feb	1943Dec	1943Mar
Wing load[kg/m2]	110	182	188	208	251	107	128	160	170	179
Wing span[m]	11.58	10.23	12.49	11.29	11.29	12.0	11.0	10.8	11.99	11.3

Russia and Japan were underdeveloped with aero industry. I-16 showed its performance to other nations in Spanish Civil War and Nomonhan Incident. IJA lost a lot of pilots in Nomonhan. So next to Ki-27, Ki-43 equipped self sealed oil tank and armor behind pilot. Otherwise IJN did not learn as USN learned the Battle of Britain. So Zero had no sealed fuel tank and armor behind pilot till the end of the Pacific War.

Yak-7 fought Bf109F at first. At last La-5 was competitive in Stalingrad. La-7 and Yak-3 overwhelmed enemy in Berlin. Yak-3 was excellent aero dynamic and designed light. La-7 equipped an air cooled engine, ASh-82FN (1,850hp) and could climb 5,000m in 4min 30sec.

Otherwise Japan failed to product the 1,860hp engine designated Ha-45. Ki-100 exchanged liquid cooled to air cooled radial engine, Mitsubishi Kinsei-62 too late, as LaGG-3 did well.
Syoumou to hoten

Machining aircraft parts

Tbl.3 Aircraft in the Pacific

Date	US	Japan
1941Dec	1,692	2,625
1943Jan	3,537	3,200
1944Jan	11,442	4,050

Tbl.2 Aircraft production

Year	US	UK	Germany	Japan
1941	19,433	20,094	11,766	5,088
1942	47,836	23,672	15,556	8,861
1944	96,318	26,461	39,807	28,180

Tbl.2 shows aircraft production of US, UK, Germany and Japan. US aircraft production increased 246% in 1942, while Japan 175% only. Did Japan think she won the Pacific War? Japan made aircraft with desperate effort in 1944 and increased the production. How about other productions? Tbl.1 shows US vs Japan production ratio in 1944 fiscal year. Basic material for production decreased very few. Japan productioned only one fortieth of steel, compared with 17.7 in 1941^[1]. This might mean that merchant ships could not ferry iron to Japan mainland. Japanese leaders did not plan the war well, though Japanese researchers studied the total war in 1941. Tbl.3 shows how many aircraft US and Japan deployed in the Pacific^[2]. What happened in 1943? US and Australia could supplied with aircraft, but IJA failed to ferry and IJN lost too aircrews in 1943. 20 Ki-45 kai of 13th Sentai departed from Japan to Rabaul on 20 April, but only 6 arrived there because of unskilled pilots and out of order^[3]. Although Japan productioned more than 3 fold aircraft in 1944 than the previous year, Japan could not deploy them enough. I think that Japan could not ferry gasoline, ammo, parts and aircraft well from Japan mainland. IJN could not defend merchant ships even from Taiwan to Philippines in 1944. While US could ferry aircraft with a lot of escort aircraft carriers. US wartime merchant ships transported huge munitions far from US mainland.

IJA airforce
IJA had 1,800 operational aircraft on 15 September 1943. The force was despersed all around the Pacifice, as followed 36 SQ in domestic, 51 SQ in Manchuria, 24 SQ in China, 71 SQ in the Pacific. IJA 7th Wing Group moved to Buto from Ambon in July 1943, which had 250 aircraft. The 7th Wing Group moved to Ambon in November and its aircraft decreased to 150 in December. IJA deployed half of aircraft in China and Manchuria, though Japan had to defend thePacific against 3 folds of US aircraft in 1944.

Inspection tour
President Franklin Delano Roosevelt' wartime tour in September and October 1942. A site shows his inspection of Boeing Aircraft Plant Seattle Washington in WW II

Piston ring
A recent Niigata-jishin ( Niigataken Chuetsu-oki Earthquake in 2007 ) stopped production of autos all over Japan for a few weeks. Because a manufacturing factory of Niigata has supplied simple piston rings for almost of domestic car engines. Why Riken built such a place unconvinent for transport?
2007 Chūetsu offshore earthquake

Successive earthquakes in Tokyo

Year of Earthquake

Order	Tokyo (Edo)	Kyoto
Latest	1923	1662
Before	1855	686

I had lived in Tokyo for 8 years. I was surprised that small earthquakes often occures in Tokyo. I also lived in Kyoto and have lived near Kyoto more than 20 years. There are few earthquakes in Kyoto. A scholar predicts, 'Big earthquake will be to occur in Tokyo probability 70% by 2036.' The table shows years of 2 historical recent big earthquakes in Kyoto and Tokyo. Big Earthquake of 1923 is called Kanto Dai Shinsai. Tokugawa Ieyasu selected Edo to govern Kanto. I think Tokugawa Ieyasu did not mind much because he was from Mikawa, of which is near Nagoya. He lived in Sunpu(Shizuoka) near Mikawa after retiring Shogunate. Sooner or later Nagoya or Tokyo will damage in near future. Japan began the Pacific War after the Big Earthquake of Tokyo in 18 years later and Meiji Restoration after Ansei Earthquake in 13 years later.

Great Kantou earthquake damaged 3.7 folds of government budget
Government outcame 10% of budget as restoration expenditure. This occurred curb of arms in 1925.
Morimoto, p286
1923 Great Kantou earthquake
Ansei no Dai-jisin
Edo

Nowdays
Toshiba was suspected that USN could not trace Soviet silenced submarines because of working propellants by Toshiba's 5-axis machine tool and Swedish NC in the cold war. Although that was not true, the story showed anxiety inferior than machine tool industry of Japan in the cold war. Now, Japan, Germany, China, Italy and Taiwan are nations of machine tools production.
Toshiba Kikai COCOM Ihan Jiken

Japan had been No.1 of machine tool production in the world since 1982. Japan slipped at No.3 in 2009.

日本工作機械工業会（日工会）が１５日発表した２０１０年主要国の切削型工作機械生産額調査によると日本の生産額は前年比８１・６％増の１０５億８０００万ドルで、ドイツを抜いて２位に浮上した。 　世界首位は２年連続で中国だった。中国は同２７・０％増の１４６億８０００万ドルで、０８年の日本の過去最高額１３５億４２００万ドルを超えた。 　世界生産額は同２３・９％増の４８３億９８００万ドルと２年ぶりに増加した。日本の世界シェアは同７・０ポイント増の２１・９％。首位の中国は同０・７ポイント増の３０・３％と続伸。３位のドイツは欧州の経済悪化が響き、生産額が同１２・６％減の６８億６２００万ドル、シェアが同５・９ポイント減の１４・２％になった。また韓国、台湾がイタリアを抜いて５強に食い込んだ。アジア勢が需要国だけではなく、生産国としても台頭している。

　米調査会社ガードナーの調べによれば、２００９年の切削型工作機械の生産額で、日本の世界シェアは約１５％となり２８％の中国、２０％のドイツに抜かれ、８２年以降２７年続いていた首位の座を明け渡し３位に転落した。日本の同機械の０９年生産額は前年比５６．５％減の５８．９億ドル（約５３００億円）と、同３５．２％減（７８．２億ドル）のドイツと比べ下落幅が大きい。初の首位となった中国は、同８．９％増の１０９．５億ドルだった。 　要因のひとつとして、日本工作機械工業会の中村健一会長は「グローバリゼーションの反動」を挙げる。日本の工作機械業界の主要顧客である日系製造業は、トヨタ自動車 <7203> やコマツ <6301> をはじめ海外市場の強化戦略をとってきた。工作機械メーカーも０８年までその恩恵を大きく受けてきたが、景気後退で極端な需要減少に直面。「リーマン・ショック後に円高が進んだことも痛手」（中村会長）となった。輸出比率の高さから、景況感の悪化だけではなく為替影響による競争環境の悪化ものし掛かった。こうした事情が、主力市場をユーロ圏内に持つ欧州メーカーと比べ、シェア後退が顕著となったことの背景にあるという。 　牧野フライス製作所 <6135> の牧野二郎社長も、「中国市場などでは実際、欧州メーカーが勢力を伸ばすなど、日本メーカーは苦戦している」と話す。ユーロ安を背景に、欧州メーカーは現地自動車メーカーなどの需要獲得を有利に進めている状況。牧野社長は「中国以外の新興国でも同じようなことが言える」と警戒感を強めている。 　一方、中国の生産額が世界首位となったことに対する不安の声は小さい。「中国メーカーは技術的に日本と競合する域にまだ達していない」（中村会長）ことから、当面は大きな脅威にはならないとする見方があるためだ。浜井産業 <6131> の武藤公志会長は「世界需要が回復しても、日本は数の上ではもう中国に追いつけないだろう」と指摘し、「今後は、欧州メーカーと新興国市場でいかに争っていけるかが重要となる」としている。（鈴木草太） 提供：モーニングスター社

Children's Day	Flower Ayame

[1] Nomonhan Jiken Senbotsu-sha su