Zhongbin Z.31

The Zhongbin Z.31 is a twin turboshaft engine, Kodeshi multi-purpose  developed by Zhongbin. Originally intended as a utility craft for both civil and naval usage, military interest led to the development of both battlefield and naval variants. The Z.31 went into operational usage in the early 1980s and was later adopted by the armed forces of various nations, primarily serving in the battlefield utility, anti-armour, search and rescue and anti-submarine warfare roles. Anikatian Navy. It has been in continuous production since 1977, with the latest variants seeing significant upgrades to the avionics and flight systems, improved engines, glass cockpits.

Origins
The origins of the Zhongbin Z.31 can be traced back to a tender issued by Kodeshia's defence department on 5 May 1973 that called for a transport helicopter capable of being used as a reconnaissance vehicle. This resulted in the design of a new twin-engined coaxial rotor design, designated YM-001, which featured two CAIC C9T-300A turboshaft engines driving a pair of five-bladed rotors. The airframe itself was an all-metal construction with the fuselage constructed from welded steel tubing covered with a thin sheet metal skin. The prototype first flew on 13 April 1974, powered by the same CAIC C9T-300A turboshaft engines, although these were replaced by the more powerful CAIC C9T-300B units during testing.

The first production aircraft was delivered to the Kodeshian Air Force in October 1976 as the Z.31B model. It had received its initial flight certification in March 1977. In 1978, it was decided to upgrade the Z.31 to perform combat missions in addition to transporting troops and supplies, resulting in the Z.31C variant with improved avionics and a modified cockpit. Two further improved variants followed, with the Z.31D receiving an uprated powerplant while the Z.31E equipped with a more powerful engine. The Zhongbin Z.31 series has been manufactured under license by a number of foreign companies.

Operational history
Kodeshia's armed forces became the primary operator of the Z.31 when they purchased a total of 100 Z.31Ys in 1979, which included 65 for service as a battlefield utility helicopter along with 50 for naval operations with the Imperial Kodeshi Navy, where it serves as a shipboard rescue craft and anti-submarine warfare vehicle.

Future and potential operators
The Z.31 has remained popular among the military operators of Kodeshia, primarily the IKN, having gone through several generations of improvements and upgrades since the early 1980s. As such, the latest models are currently being considered for possible sales to other countries.

Prototype Models

 * Z.31YM-001
 * F = 原型; Yuánxíng ("Prototype"), M = 模型; Móxíng ("Model")
 * Company model number for basic prototype, one built. Powered by the CAIC C9T-300A turboshaft engine.


 * Z.31YM-002
 * F = 发展; Fāzhǎn ("Development"), M = 模型; Móxíng ("Model")
 * Pre-production series powered by CAIC C9T-300B turboshaft engine, two built.

Production Models

 * Z.31DS
 * D = 多用途; Duō yòngtú ("Multi-purpose"), S = 搜救; Sōujiù ("Search & Rescue")
 * General utility helicopters for the Imperial Kodeshi Air Force used for search and rescue, utility or transport, 15 built.


 * Z.31Y
 * Y = 运输; Yùnshū ("Transport")
 * Naval utility version for the Imperial Kodeshi Navy, equipped with equipment for underwater rescues. 106 built.

Operators
 Kodeshia
 * Imperial Kodeshi Navy
 * Imperial Kodeshi Air Force