The Sumida model P model is here

Kindly corrected by Mr Takizawa

In 1930 was produced the first purely Japanese armored car which was more like an armored truck, under the name Sumida P by Ishikawajima. This vehicle was only used by the landing forces of the Imperial Japanese Navy (SNLF: Special Naval Landing Forces). We must not forget the ceaseless struggle for influence between the Army (IJA: Imperial Japan Army) and the Navy (IJN: Imperial Japan Navy) which also had its own land forces (landing forces identical to the American Marines) . This version was on the other hand intended only for the road contrary to the version of the Army (IJA) type 91/93 So-Mo which could be adapted for the rail. It seems that this vehicle was manufactured in three copies, although Kunimoto stated that five copies were purchased (two stationned in Tsingtao and three in Shangaï after 1938). There are few photos, there are markings 1 and 3 only and there is a photo on which we see the three together. Like the later version type 91/93, the Sumida model P armored car did not carry fixed weapons because the army reserved the fixed weapons for the infantry, artillery and cavalry but it was provided with ball joints or hatches for machine guns (type 11 light machine gun) or rifles. It was therefore a vehicle very suitable for urban combat, on the other hand, off the roads, it had to be unusable with its narrow wheels with solid tires.​

In Japan as in other countries, the populations could finance the construction of vehicles for the Army or the Navy, which was the case for the sumida P armored car. These were two associations designated Hokoku for the Navy and Aikoku for the Army who took care of this task. This is what we see as an inscription on the sides of the body, it is also why this vehicle is sometimes incorrectly referred to as the Hokoku type. Vehicle No.1 was funded by the city of Nagaoka. ​

. ​There were early Sumida model P with no rear fenders and no ball mounts and late models with rear fenders and ball mounts, nobody knows how many of each were delivered, all in all, there were three sumida model P.

These vehicles were received by the navy in July 1932 so too late to participate in the first incident in Shanghai, but some photos show some vehicles in action during the second battle of Shanghai in 1937. These vehicles were part of the SNLF Shanghai Special Naval Landing Corps armored company (the armored cars consisted of the 9 M25 Vickers Crossley purchased by the Navy and 3 Sumida Model P armored cars). Commanded by Rear Admiral Ohkochi and subordinate to Vice Admiral Hasegawa, Commander of the 3rd Fleet and Supreme Commander in Shanghai, the corps before the battle of 1937 consisted of 2,500 men (including Hankou’s detachment of 300 men). The corps included a staff battalion and six naval infantry battalions including the 4th artillery (4 x 150 mm howitzers, 4 x 120 mm howitzers, 12 x 75 mm mountain guns, 4 x 70 mm infantry guns, 4 x 20 mm anti-aircraft guns, 8 x heavy mortars 150 mm). The armored company (which in 1932 included only 9 M25 Vickers Crossley armored cars) was reinforced after 1932 with 4 medium tanks type 89 (1 type A early, 3 type A late), 3 Sumida P armored cars, 3 naval type 93 armored cars, 4 Carden loyd VIb light tanks. This new armored detachment was commanded by Captain Yoshino Keizo. Regarding the color, the vehicles were all khaki or gray. The uniform which until then had been that of the navy (dark blue in winter, white in summer) also evolved after 1932 to adopt a less showy outfit, green close to that of the army. These three vehicles were still in Shanghai in August 1945.

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