Aigókeros E71

The Aigókeros E71 (Capricorn Model 1971, sometimes shortened to 'Aigo') was a Mursian which served from 1971 to the 2000s. It replaced the Geráki E56, which had become severely outdated in both technological and strategic sense. The Aigókeros was the last domestically produced tank of Mursland, and was replaced by the Stridsvogn 3 of Ringerike in 2009.

History and development
The political situation in Mursland was impacted by the rise of Maltin Luga in the Lusjki State in the late 50s. The relations between the nations had soured and border tensions came on the rise. As a result, Mursland would quickly developed the Geráki E56 to strengthen its old tank fleet.

Although the Geráki initially functioned well as a deterrent for war, the vehicle was pragmatically designed and did not leave much room for improvements, risking getting outdated. In the late 60s, the Mursland army sought to replace the vehicle already, thus development started on what would be called the Ergo-1964. It had an advanced hydrolytic system to higher and lower the tank and a complicated turret design with many state-of-the-art technologies involved. The prototype was presented to the general staff in may 1967. It proved to be unreliable, the turret jamming on several occasions. On top of that, the Strategic Court decided that the tank would have a more open-ended design to ease later improvements.

The new prototype, called the Ergo-1967, would see a design much resembling the final product, with a simpler and more traditional turret design and a suspension resembling the Geráki. A first prototype was presented in February 1969 to the general staff. Praises were lacking, but so was critique. The vehicle proved to be reliable and pass all the trials, be it with much effort. As quick replacement was desired by the Army, the base design was approved and production could be set-up while some improvements and fine-tuning would be done.

A second prototype, Ergo-1967 A.2, would reach trials in August 1969 until December 1969, which saw various modifications of the design and extensive tests in extreme environments. From November 1969, the construction of the first base vehicle started. By March 1970, another 2 prototypes (A.3) were delivered, bare vehicles from the production line. These new hulls would be tested again to guarantee quality, and some feedback was send back together with the approval for full production speed.

Issues with the supply of gun stabilizing modules would form a severe bottle-neck for the production and the first batch of 12 vehicles were delivered in March 1971, a full year after approval for production was granted.

Service
The Aigókeros entered Mursian service in 1971 were it was distributed among the armoured regiment. It slowly phased out the Geráki which retired service in 1976 as the A.2 upgrade was executed.

It saw positive reviews of the army with its introduction. However, over the years, as the tank became outdated, resentment grew towards it as many of the vehicles started to show defects. They were refurbished to new standards in 1990, and saw a life extension program in 2003.

The vehicle ended up never seeing combat and was retired in the 10s. It was succeeded by reconditioned Stridsvogn 3s from the Ringerike Army. The bridgelaying variant remains in service using the last reserve parts and is planned for retirement in 2025.

Variants

 * Ergo-1964 - First prototype, returned to factory
 * Ergo-1967 A.1 and A.2 - Second and third prototype, later stripped and used for target practice.
 * Ergo-1967 A.3 - Fourth and fifth prototype, barebone production vehicles. Later properly equipped and recategorized as Aigókeros E71 A.0
 * Aigókeros E71 A.0 - 1st series production model; 120 built + 2 converted.
 * Aigókeros E71 A.1 - 2nd series production model; 126 built.
 * Aigókeros Géfyra - variant, 3 built. Brü Pz 68-88 - Schweizer Armee - Steel Parade 2006.jpg
 * Aigókeros E71 A.2 - 1976 upgrade to radio systems and refit of all the hatches to mitigate concerns with.
 * Aigókeros E71 A.3 - 3rd series production model; 60 built.
 * Aigókeros E71 A.4 - 1990 refit with new imaging electronics and improved gun handling. Some of the hulls were refurbished.
 * Aigókeros E71 A.5 - 2003 life extension upgrade.