Throughout history, military forces have used tanks as a crucial part of their arsenal. Tanks provide protection, firepower and mobility on the battlefield. However, not all tanks are created equal. Some have proven far more effective and reliable than others. This raises an interesting question – what was objectively the weakest tank design in history? Determining the “weakest” tank is subjective to a degree, but by evaluating factors like armor protection, armament, mobility, mechanical reliability and crew ergonomics, we can identify designs that consistently underperformed in combat. In this article, we will examine some of the least effective tank models and determine which has the strongest claim to the title of “weakest tank in history.”
Background on Tank Development
Before evaluating specific tank designs, it is helpful to understand some key aspects of tank development through history:
- Tanks first appeared in World War I as a solution to trench warfare, with early models like the British Mark I being primitive but revolutionary.
- During the interwar period, tank design and tactics advanced rapidly with new technologies and lessons from wartime experience.
- World War II saw tanks like the German Panther and Soviet T-34 become much more powerful and effective than their WWI-era predecessors.
- The Cold War sparked an arms race between NATO and Warsaw Pact nations, resulting in advanced main battle tanks like the U.S. M1 Abrams and Soviet T-72.
- Modern tanks benefit from sophisticated armor, targeting systems, hydraulics, communications, and engines – technology unimaginable to early tank designers.
So tank design has steadily advanced over the past century to produce the powerful armored vehicles we see today. With that context, let’s examine some of the least capable tanks ever fielded and see which has the strongest claim to the dubious title of “weakest tank.”
The Contenders
There are several Cold War-era and earlier tanks that are frequently cited as among the worst or most ineffective ever built. Here are four of the leading candidates for the weakest tank:
M22 Locust – United States
The M22 Locust was an American light tank developed during World War II. It weighed just under 20,000 lbs and had a crew of 3-4. With a 37mm main gun and .50 caliber machine gun, it lacked firepower compared to other tanks of the era. The Locust’s armor was very thin, providing virtually no protection. Its small size and low ground pressure were optimized for airborne operations. However, it saw very limited combat use in the war, as it was unsuitable for most operations.
Bob Semple Tank – New Zealand
Fearing a Japanese invasion during WWII, New Zealand engineer Bob Semple fabricated a tank from available materials including corrugated iron and timber. The resulting vehicle was slow, cumbersome, and offered negligible protection. Its most effective armament was machine guns in sponsons. While a creative attempt at armored vehicle design under the pressures of war, the Bob Semple tank proved wholly impractical in testing.
T-70 – Soviet Union
The T-70 light tank entered service with the Red Army in 1942. As German armor outgunned early-war Soviet tanks, the T-70 was meant to be a mobile, reconnaissance-focused vehicle. However, it had extremely light armor of just 20-35mm thickness. Its 2-man crew and two 7.62mm machine guns gave it little offensive punch compared to other tanks. The T-70 suffered horrendous losses when pitted against Panzers, contributing to it being replaced by better designs like the T-34.
Renault FT-17 – France
The Renault FT-17 was truly revolutionary as the first tank with a rotating turret, pioneering design norms for decades. However, by the opening years of WWII, it was thoroughly outdated. The FT-17 had maximum armor just 22mm thick and a low-velocity 37mm gun. France’s desperate reliance on the FT-17 early in WWII demonstrated how far tank design had come since WWI. It was completely outmatched by later tanks in firepower, protection, and mobility.
Evaluating the Candidates
Now that we have looked at some of the most notoriously ineffective tank models, let’s directly compare them across some key criteria to determine the weakest overall design:
Armor Protection
| Tank Model | Armor Thickness |
| M22 Locust | 12-25mm |
| Bob Semple | 6-12mm |
| T-70 | 20-35mm |
| Renault FT-17 | 8-22mm |
The Bob Semple has by far the thinnest armor, providing virtually no protection against any anti-tank weapons of the era. The other tanks all have marginally better protection.
Firepower
The M22 Locust and Bob Semple both rely on machine guns for armament, which are not very effective against other tanks. The 37mm guns of the T-70 and FT-17 were obsolete by WWII standards. The T-70 has a slight edge with its gun being more modern.
Mobility
The ultra-light M22 Locust wins here, designed expressly for high mobility and air transportability to compensate for its thin armor. The lumbering Bob Semple was a veritable snail in comparison.
Mechanical Reliability
The M22 Locust and T-70 were mass produced designs with more rigorous quality control and testing compared to the hand-built Bob Semple. The Renault FT-17 was outdated by the 1930s and prone to breakdowns when stressed in combat.
Survivability
Virtually none of these tanks afforded their crews meaningful protection or survival rates against enemy fire. The T-70 and M22 Locust lose again due to thinner armor and open crew compartments. The low-slung FT-17 had marginally better crew protection.
The Winner? Bob Semple Tank
While all these tanks had significant deficiencies compared to other armored vehicles of their day, the Bob Semple stands out as the weakest design overall when synthesizing the evaluation criteria. Its homemade construction, lackluster mobility, and near-zero armor made it wholly unfit for combat duties against any reasonably armed opponent. The tank clearly demonstrates desperate improvisation rather than a deliberately engineered AFV. The M22 Locust, T-70 and FT-17 were all fatally flawed, but remain recognizable as tank designs reflecting armored warfare needs and doctrine of their periods. For these reasons, the Bob Semple Tank can safely claim the dubious honor of being the weakest tank design in history. Its overwhelming inadequacies mark it as an interesting historical footnote rather than a meaningful armored vehicle.
Improving Tank Design
The weaknesses of tanks like the Bob Semple highlight how far armored vehicle engineering has come over the past century. Modern main battle tanks are massive, sophisticated machines designed with lessons learned from earlier periods of mechanized warfare. However, tanks are highly complex tech systems involving tradeoffs between firepower, armor, mobility and overall mass.
Here are some ways emerging technologies may further improve tank capabilities:
- New armor materials like composites, reactive armor and active protection systems to optimize defense against different threats
- More powerful engines and improved drivetrains for better speed and mobility
- Unmanned turrets and automation to reduce crew requirements
- Networked systems and advanced sensors for greater situational awareness
- Electric or hybrid powertrains for fuel efficiency and stealth
With continued innovation, the main battle tank will remain a dominant force on the battlefield for decades to come. The weaknesses of past designs like the Bob Semple highlight just how far tank engineering has progressed over the past century.
Conclusion
In reviewing some of the least capable tank designs in history, the New Zealand Bob Semple clearly stands out as the weakest overall. Its pathetic armor protection, poor mobility, lack of real armament, and general inadequacy make it wholly unfit as a combat vehicle. While tanks like the M22 Locust, T-70 and Renault FT-17 were also deeply flawed, they at least represent deliberate tank engineering for their periods. The Bob Semple was an act of wartime improvisation using whatever materials were available. As an extreme example of inadequate armor protection and offensive firepower, the Bob Semple Tank has rightfully earned its reputation as the weakest tank design in history. By highlighting how far tank engineering has come, the Bob Semple also points to how technologies like new armor materials, sophisticated sensors and alternative powertrains will continue improving tanks well into the future.