For many years the mainstay of the Republic of Korea (ROK) self-Propelled field artillery units has been the United Defense LP 155 mm/39calibre M109A2 self- propelled howitzer.
Samsung Techwin Defense Program Division was the prime contractor of ROK for the co-production of 1,040 M 109A2 SPH deliveries of which had completed several years ago.
In the late 1980s, the ROK Army drew up its requirements for a new 155mm/52calibre tracked SPH to meet the requirements of the 21st century¡¯s warfare which are based on the following missions.

Deep supporting fire of the corps, qualitatively superior to overcome the numerical inferiority and effective firing support in mountainous areas with its longer range. Agency for Defense Development (ADD) started development of a new SPH in 1989.

Key operational requirements included higher rate of fire, longer range, more accurate fire, faster into and out of action times and greater mobility, all of which lead to a significant increase in battlefield survivability of the weapon system.

Following a competition, the now Samsung Techwin was selected to be the prime contractor for the K9 Thunder 155 mm/52calibre SPH development.
First prototypes were completed in 1994 under the designation XK9 and put through an extensive series of Development Test/Operational Test (DT/OT) by the ROK Army and the ADD.
These were followed by three preproduction vehicles manufactured during the full-scale development phase (Phase II), the last of which was completed in 1998.

The mobility and firing reliability of the K9 Thunder had been verified through the trials of the prototype vehicles in Korea and these had traveled 18,000 km and fired 12,000 rounds by the end of 1998.
The XK9 Thunder was type Classified by the ROK Army in 1998 as the K9, with the fist production vehicles being completed earlier in 1999.

By late 2005 over 250 of K9 have been fielded for fire support of a corps of artillery without replacing the existing towed and self-propelled systems. One thunder battalion has three batteries, each with six weapons. Each battery is normally controlled by one battery fire-direction centre.
The ROK Army is the first in Asia to deploy a 155 mm/52calibre SPH and the second in the world. Late in 2001, it was revealed the Turkish Land Forces Command (TLFC) had signed in contract with the Defense Program Division of Samsung TechWin for the 155mm K9 self-propelled artillery system.
Under the terms of this deal, South Korea supplied a first batch of K9 systems with progressive licensed production then being undertaken in Turkey.
Following trials with a prototype, an order for an undisclosed quantity of systems was placed with the first batch understood to consist of eight units.

Production commenced in 2002 and the total TLFC requirement could be for as many as 300 systems, funding permitting. In 2004 the Turkish Land Forces Command (TLFC) took delivery of the first of its Firtina 155mm/52calibre Self-Propelled Guns (SPGs).
Firtina, or T-155 K/M Obus as it is also referred to, has a combat weight of 47tonnes and is powered by a MTU 881 series diesel developon 1,000 hp coupled to an Allison X1100-5A3 fully automatic transmission. Maximum road speed os quoted as 65 km/h with a cruising range of 360 to 400km.

Development of K9 Thunder Proven performance & Reliability
Superior fire power Shoot & Scoot
Higher Mobility Protection
Automatic control system Specification
Video & Images