The Kayaba Ka-1 is a Japanese reconnaissance gyroplane created during the Second World War. This aircraft was used as a close (including naval) reconnaissance aircraft, including for adjusting artillery fire and fighting submarines. The gyroplane was manufactured by the Japanese company Kayaba Seisakusho. The autogyro was used by the Imperial Japanese Army from 1942 to 1945. During this time, 98 aircraft were produced in two versions: Ka-1 and Ka-2.
In the late 1930s, the Japanese military, who were trying to focus on the most advanced developments in the world of aircraft construction, drew attention to the rotorcraft that had just begun to appear - autogyros. The military of many countries was attracted by the ability of these machines to take off almost vertically and literally hover in the air over one place. Such capabilities made it possible to count on the high efficiency of their use as artillery spotters. In Japan, there were simply no such samples of technology, so they decided to look for suitable aircraft abroad.
Autogyro Kellett KD-1
The first gyroplane was invented by an engineer from Spain, Juan de la Cierva, in 1919. His C-4 gyroplane made its maiden flight on January 9, 1923. The main period of development of these aircraft fell on the 30s of the last century. The autogyro was a rotary-wing aircraft that used a rotor that rotates freely in autorotation mode to create lift. Another name for a gyroplane is a gyroplane (this term is officially used by the US Federal Aviation Administration).
Like helicopters, the gyroplane has a main rotor that creates lift, but the gyroplane's rotor rotates freely under the action of aerodynamic forces in autorotation mode. In order to fly, in addition to a freely rotating main rotor, the gyroplane has an engine with a pulling or pushing rotor (propeller), which provides the aircraft with horizontal speed and thrust. When the gyroplane moves forward, the necessary counter flow of air is created, which flows around the main rotor in a certain way and makes it go into the autorotation mode, rotate, while creating the necessary lifting force.
The vast majority of gyroplanes are not able to take off vertically, however, they require a significantly shorter take-off roll (10-50 meters in the presence of a rotor pre-spin system) than airplanes. Almost all gyroplanes are capable of landing without a run or with a range of only a few meters, moreover, they can sometimes hover in the air, but only in a very strong headwind. In terms of maneuverability and their capabilities in the air, gyroplanes occupied an intermediate niche between aircraft and helicopters.
Autogyro Kayaba Ka-1
In 1939, the Japanese purchased one copy of the Kellett KD-1A gyroplane in the United States through dummies. Created in 1934, the gyroplane in its external layout was similar to the English apparatus Cierva C.30. He also had two open cockpits and assumed tandem accommodation for crew members. The model was powered by a Jacobs R-755 7-cylinder air-cooled radial engine, which developed a maximum power of 225 hp. This engine drove a three-bladed main rotor with folding blades, which was equipped with a mechanical system for spinning and a brake.
After the delivery of the KD-1A gyroplane in Japan, tests began. The flight characteristics demonstrated by the device suited the military, however, during one of the flights, the gyroplane suffered an accident, having received significant damage. The aircraft was beyond repair. The wreckage of the American gyroplane was transferred to the small company Kayaba, which was supposed to create its own military analogue of the apparatus on their basis. The first Japanese-made gyroplane, designated the Kayaba Ka-1, was produced by the Sendai plant. It was a two-seater reconnaissance gyroplane, similar in appearance to the Kellett KD-1A, but modified to meet Japanese standards. The machine made its maiden flight on May 26, 1941. The aircraft differed from its overseas predecessor mainly in the engine - instead of the Jacobs radial engine, it was equipped with an Argus As 10 engine of greater power - 240 hp.
The tests of the Japanese gyroplane were very successful. It could take off from a platform only 30 meters long, and with an engine that worked at full power, at an angle of attack of 15 degrees, it could practically hover over one place, and also simultaneously perform a turn around its axis - 360 degrees. Among other things, the car turned out to be very easy to maintain, which the military also paid increased attention to.
Autogyro Kayaba Ka-1
The capabilities demonstrated by the gyroplane were completely satisfied with the representatives of the Imperial Japanese Army, so it was sent to mass production. Already in 1941, the aircraft began to enter the artillery units, where it was planned to use them for adjusting fire from the air. The autogyro was produced in an extremely limited batch. Some sources refer to 98 produced copies, in others about 240 produced gyroplanes. Most likely, they were released, indeed, an extremely small number, which determined their episodic use in hostilities, on which they could not have any significant impact. It is believed that only 20 of the Kayaba Ka-1 gyroplanes were produced, after which they began to produce the Ka-2 version, which had the same Jacobs R-755 engine as the American version. The total number of Ka-1 and Ka-2 autogyro fuselages produced before the end of World War II is estimated at 98, of which 12 were destroyed before being transferred to the army, of the remaining 30 engines were not installed. As a result, the army received only about 50 such aircraft, of which about 30 machines were used.
Initially, the Japanese army leadership expected to use the Kayaba Ka-1 gyroplanes in China to adjust the fire of artillery units, but the changing course of the war required strengthening the defense of the Philippines, where the gyroplanes were sent as liaison aircraft instead of the Kokusai Ki-76. It was a Japanese communications aircraft based on the German Fieseler Fi 156 Storch.
After the Japanese ground army got its own escort aircraft carrier "Akitsu-maru", which was converted from an ordinary passenger liner, which, in turn, became a landing ship with the outbreak of war, several Kayaba Ka-1 gyroplanes entered service. From reconnaissance they were converted into anti-submarine. Since the payload in the two-seater version was extremely insignificant, the crew of the gyroplanes located on the aircraft carrier was reduced from two to one person. This made it possible to take on board up to two 60-kg depth charges. In a new capacity for themselves, the Ka-1 gyroplanes were engaged in patrolling the territorial waters of the land of the rising sun.
Ultimately, most of the existing Kayaba Ka-1 and Ka-2 gyroplanes were converted for anti-submarine patrol service. On the escort aircraft carrier "Akitsu-maru" they were deployed from August to November 1944. Along with the Ki-76 aircraft, they were the only aircraft that could land on the short flight deck of this escort aircraft carrier, while it was most often used as a ferry for the transport of aircraft. The ship was sunk by an American submarine on November 15, 1944.
Autogyro Kayaba Ka-1
Beginning on January 17, 1945, Ka-1 gyroplanes were used for anti-submarine patrols from airfields located on the island of Iki. The service base was located at the Gannosu airfield in Fukoka prefecture. Since May 1945, they have been patrolling the waters of the Tsushima and Korea Straits from Tsushima Island. After some time, the zone of action of the American carrier-based aircraft reached the Tsushima Strait, so in June the surviving Ka-1 and Ka-2 gyroplanes were redeployed to the Noto Peninsula, where they remained until the end of the war. These gyroplanes did not manage to sink a single enemy submarine, however, they performed their reconnaissance function, being engaged in the detection of submarines.
Flight performance of Kayaba Ka-1:
Overall dimensions: length - 6, 68 m, height - 3, 1 m, rotor diameter - 12, 2 m.
Empty weight - 775 kg.
Maximum takeoff weight - 1170 kg.
The power plant is an air-cooled Argus As 10 engine with a capacity of 240 hp.
Maximum flight speed - 165 km / h, cruising speed - 115 km / h.
Practical flight range - 280 km.
Service ceiling - 3500 m.
Crew - 1-2 people.
Armament - it was possible to suspend two depth charges weighing 60 kg each.
