The PHZ89 (also known as Type 89) is the 122mm, 40-tube self-propelled multiple rocket launcher (MRL) that entered the PLA service in 1990. The main contractor is China North Industries Group Corporation (CNGC), and the development and production of the weapon has been carried out by Harbin First Machinery Factory (674 Factory) and Hubei Jiangshan Machinery Factory (5137 Factory). The weapon is in service with PLA armoured divisions to provide highly intensive and large coverage firepower, replacing the older Type 70 130mm, 19-tube self-propelled MRL.

In the early 1980s, 674 Factory and 5137 Factory jointly developed a 122mm self-propelled MRL mounted on a tracked chassis. The weapon system was initially intended for the export market. The MRL system completed the design stage in 1985, but it did not enter production due to lack of interest from the international market. Instead, the weapon was adopted by the PLA in 1986 as the next-generation artillery rocket system for its armoured forces.

The PLA issued a number of requirements for the improvement of the design, including automated launcher operation and reloading, the addition of a 12.7mm anti-aircraft machine gun (AAMG), reduced noise and collective anti-NBT system. A prototype rolled out in February 1987. The development testing was carried out between March and November of the same year. Trails in a weapon testing base and filed units were carried out in 1988, with a total travelling distance of over 30,000km and 707 rounds fired. In February, the weapon was approved by the State Council and Central Military Commission for production, and weapon was officially designated PHZ89.

The rocket launcher of the PHZ89 was developed from the Type 81 122mm MRL system, which was a Chinese copy of the Russian BM-21 ‘Grad’. The PHZ89 is mounted on the Type 321 utility tracked chassis developed from the Type 83 152mm self-propelled gun-howitzer. The vehicle is powered by a WR-4B 520hp liquid-cooled diesel. The chassis has six unevenly spaced road wheels and three track support rollers. The system has a combat weight of 30t and a maximum road speed of 55km/h. The system is operated by a crew of five men, who are protected by limited armour protection and a centralised NBC-protection system.

The weapon system fires 122mm free rockets to a maximum range of 20~30km depending on the warhead type. The rocket consists of one piece, with the warhead attached with the rocket motor. A fixed amount of propellant is contained in the rocket motor. The rocket uses fin and low speed spin stabilisation to ensure the firing accuracy. The rocket delivers high-explosive (HE) warheads containing steel balls and prefabricated fragments. NORINCO has also developed a range of specialised warheads including High-Explosive Incendiary (HEI), anti-tank/anti-personnel submunition, and mind-laying, all of which can be fired from the Type 89 launcher.

The rocket launcher and reloading rack are mounted on the tracked Type 321 utility chassis. The electrically powered launcher has four rows of 10 tubes mounted above each other on a rotating cradle assembly. The launch tubes have an elevation range of 0° to 55° and azimuth range of -102° to +66°. The electrical firing system fires the rockets in either single or in salvo with 0.5 seconds interval. The Type 81 can fire 40 rockets in 20 seconds. The automatic reloading system can reload the launcher within 3 minutes.

The secondary weapon is a 12.7mm/50-calibre antiaircraft machinegun mounted on the cupola of a small machinegun turret located on the left of the launcher.

Firing accuracy is attained by a computerised fire-control system, which can receive target information automatically from the command vehicle, or by manual input. The fire-control computer then calculates the ballistic and adjust according to the vehicle’s slope and gradient before launch.