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MAM-07-X3 Grublo Underwater Bit-Mounted Prototype

Prototype underwater mobile armor developed by MIP Company for the Principality of Zeon.
Jenxi Seow Published 22 Dec 2013 Updated 7 Feb 2025
MAM-07-X3 Grublo Underwater Bit-Mounted Prototype

The MAM-07-X3 Grublo Underwater Bit-Mounted Prototype was a prototype underwater mobile armor developed by MIP Company for the Principality of Zeon. It was an experimental variant of the MAM-07 Grublo fitted with underwater bits and a quasi-psycommu system.

The “MA” in the type code indicated it was a mobile armor, and the “M” meant it was amphibious. The “07” model number denoted it was the seventh design for this type. The “X3” block number meant it was the third experimental version.

History

The MAM-07 Grublo was one of the earliest mobile armors used by the Principality of Zeon during the One Year War. MIP Company developed it based on the MA-05 Bigro, taking one and a half months to complete.

Three Grublo units were constructed in the submarine dock of California Base. During testing in the Gulf of Mexico, one unit was modified with a quasi-psycommu system and underwater bits, designated as the MAM-07-X3 Grublo Underwater Bit-Mounted Prototype.

Tests were conducted for about two weeks, during which the prototype encountered two Earth Federation warships and sank them within an hour. Although the development team was satisfied with its performance, the MAM-07-X3 was not formally adopted for production and was later restored to a standard Grublo configuration.

Design

The MAM-07-X3 Grublo Underwater Bit-Mounted Prototype was a modified MAM-07 Grublo with its claw arms replaced by underwater-use bits. The rear fuselage was equipped with complex transmission units to control the bits.

It featured a quasi-psycommu system that allowed normal pilots to operate the remote weapons. A sonar dome was attached underneath to enhance detection and ranging capabilities underwater.

The mobile armor retained the Minovsky ultracompact fusion reactor of the base Grublo, rated at 11,000 kW output. Propulsion was provided by two hydrojet engines.

Armaments

The Grublo Underwater Bit-Mounted Prototype’s standard weapons were torpedo launchers for ship and submarine attacks, missile launchers for air defense, and underwater bits for enhanced combat capability.

Seven-tube torpedo launcher

Two seven-tube torpedo launchers were mounted on the main body. Each tube carried three rounds, giving the mobile armor a total of forty-two torpedoes. Even glancing hits from these torpedoes could significantly damage enemy mobile suits or ships.

Anti-ship/air missile launcher

Two missile launchers were mounted in the main body, each containing eight rounds. These naval-use Surface-to-Air missiles were primarily used to attack military targets near shorelines, such as docks or shipyards, as well as enemy aircraft.

Underwater bits

The prototype replaced the Grublo’s standard claws with two underwater-use bits. These remote-controlled weapons could be operated either through wired or wireless connections via the quasi-psycommu system. While slower than their space-use counterparts, limited test data proved their effectiveness in underwater combat.

Behind the scenes

Okawara Kunio was the original mechanical designer.

Appearances

  • Mobile Suit Variations-R