E-75 Mech 150mm STUG

The E-75 Mech 150mm STUG is a firepower-enhanced assault mech designed for siege warfare and heavy assault operations. Developed as a variant of the E-75 Heavy Mech series, this model features a fixed casemate structure instead of a rotating turret, enabling it to mount a 150mm high-velocity cannon for superior firepower against fortified targets. However, the increased weight and firepower resulted in reduced mobility compared to earlier models. Due to its specialized role and higher production cost, only approximately 100 units were built, but they demonstrated remarkable battlefield effectiveness in assault and urban combat scenarios.

Development and Design

Following the successful deployment of the E-75 Heavy Mech series, the need for a heavy fire-support variant became evident. While the standard E-75 Type G excelled in breakthrough and anti-armor roles, it lacked the sheer firepower necessary for destroying heavily fortified enemy positions. To address this gap, the E-75 Mech 150mm STUG was developed with a fixed superstructure, similar to traditional assault guns (Sturmgeschütz, STUG), to accommodate a massive 150mm siege cannon.

This variant retained the bipedal chassis but reinforced its frontal armor to withstand prolonged engagements against defensive fortifications. The lack of a turret simplified production while allowing engineers to focus on improving structural integrity and weapon stability. However, the increased weight—raising the total combat weight to 75 tons—resulted in a reduced top speed of 40 km/h.

Operational Role

The E-75 Mech 150mm STUG was designed for heavy assault and siege operations, excelling in scenarios where static defenses, bunkers, or fortified urban positions needed to be eliminated. The 150mm high-velocity cannon delivered devastating firepower, capable of destroying enemy armor, strongholds, and defensive emplacements with a single shot.

Although its lack of a turret limited its versatility, the mech compensated with exceptional frontal armor and a wide firing arc achieved through its hydraulic leg movement system. It was typically deployed in combined operations, advancing with supporting units to provide direct fire support against hardened targets.

Despite its limited production (approximately 100 units), the 150mm STUG variant proved to be an extremely effective combat asset, contributing significantly to offensive campaigns and urban warfare scenarios.

Power and Mobility

Due to its heavier frame, the E-75 Mech 150mm STUG utilized an upgraded 1,200-horsepower engine, but the increased weight led to a reduced top speed of 40 km/h. The bipedal movement system was reinforced to handle the additional load, ensuring stability during siege operations.

Crew and Protection

The E-75 Mech 150mm STUG retained a five-person crew, including:

• Commander – Battlefield coordination
• Gunner – Operates the 150mm cannon
• Driver – Controls movement and positioning
• Secondary Gunner – Manages defensive armament
• Engineer/Operator – Monitors mechanical systems and assists with field repairs

To compensate for the lack of a turret, frontal armor was increased, featuring 200mm of sloped plating, making it one of the most well-protected mech units in its class.

Specifications

• Weight: 75 tons
• Crew: 5 (Commander, Gunner, Driver, Secondary Gunner, Engineer/Operator)
• Armor: 200mm sloped frontal armor
• Primary Armament: 150mm high-velocity assault cannon
• Secondary Armament: Dual 30mm autocannons for defense
• Mobility System: Reinforced bipedal hydraulic leg system
• Power System: 1,200 hp engine
• Maximum Speed: 40 km/h
• Production Quantity: Approximately 100 units
• Combat Role: Siege warfare, direct fire support, urban combat

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