The Yokosuka P1Y Ginga was a twin-engine, land-based bomber developed for the Japanese Imperial Navy in World War II.
It was the successor to the Mitsubishi G4M and given the Allied reporting name “Frances”.
The P1Y was designed by the Yokosuka Naval Air Technical Arsenal to Navy specification 15-Shi calling for a fast bomber with speed matching the Zero, range matching the G4M, a 907 kg (2,000 lb) bombload, and the ability to dive-bomb as well as carry torpedoes.
As the result, the construction suffered from excess complexity, difficulty of manufacture, and poor serviceability.
Problems with the availability of enough reliable Nakajima Homare engines led to their replacement by the Mitsubishi Kasei in the P1Y2-S night-fighter version.
The streamlined design of the Ginga is attributed to Miki Tadanao, an engineer who after World War II went on to create a similar aerodynamic design for Japan’s earliest bullet trains (Shinkansen), while working with the Japan National Railways (JNR).
The first flight was in August 1943. Nakajima manufactured 1,002 examples, which were operated by five Kōkūtai (Air Groups) and acted as land-based medium and torpedo bombers from airfields in China, Taiwan, the Mariana Islands, the Philippines, the Ryukyu Islands, Shikoku, and Kyūshū.
During the last stages of the war the P1Y was used as a kamikaze aircraft against the United States Navy during the Okinawa Campaign in Operation Tan No. 2.
A night fighter version, the P1Y2-S Kyokko, with Mitsubishi Kasei engines, was equipped with radar and Schräge Musik-style upward-firing as well as forward-firing 20 mm cannon.
A total of 96 were produced by Kawanishi but due to inadequate high-altitude performance against the B-29 Superfortress, many were converted back to Ginga bombers.
P1Y1 Experimental Type 15 land-based bomber
3 prototypes and 9 supplementary prototypes with 1,357 kW (1,820 hp) NK9C Nakajima NK9B Homare 11 engines.
Prototype #3 was later used for Ishikawajima Tsu-11 testbed.
P1Y1 Ginga Model 11
First model of the series, Mounted Homare 11 or Homare 12.
P1Y1a Ginga Model 11A
Mounted Homare 12 and fitted 1 × 13 mm (.51 in) Type 2 machine gun in the back defensive position.
P1Y1b Provisional name Ginga Model 11B
Converted from P1Y1a, mounted Homare 12, and fitted 2 × 13 mm (.51 in) Type 2 machine guns in the back defensive position.
P1Y1c Provisional name Ginga Model 11C
Converted from P1Y1b, mounted Homare 12, and fitted 1 × 13 mm (.51 in) Type 2 machine gun in the forward position, prototype only.
P1Y1 Ginga Model 11 Night-fighter variant
Converted from P1Y1.
Armed with 2 × 20 mm Type 99 cannons, Equipped 302nd Kōkūtai only.
This was not naval regulation equipment.
P1Y1-S Provisional name Ginga Model 21
Night fighter variant.
Armed with 4 × 20 mm Type 99 cannons firing obliquely forward, and 1 × 13 mm (.51 in) Type 2 machine gun in the back defensive position.
Only a project.
P1Y1 Ground attack variant
converted from P1Y1/P1Y1a, installed up to 20 × 20 mm Type 99 cannons in the bomb bay for land strikes against B-29 bases in the Marianas.
Approx 30 rebuilt.
P1Y2-S Provisional name Ginga Model 26/Test production Kyokkō
Night fighter variant.
Initially named Hakkō in October 1943, renamed Kyokkō in March 1944.
Converted from P1Y1/P1Y1a.
Fitted Mitsubishi MK4T-A Kasei 25 engines.
Armed with 2 × 20 mm Type 99 cannons and 1 × 30 mm Type 5 cannon.