Too big to build or too tricky to work, these machines simply didn't pan out.
Bigger isn't always better in the world of monster machines. Sometimes big means too cumbersome to accomplish the prescribed task. Or maybe the laws of physics rules the day. Whatever the reason, we ran down seven monster machines that failed—or never happened at all—either because of their monstrous size or outsized ambition.
Charles Babbage had plans in the mid-1800s for the largest programmable computing engine ever designed. The machine could use punch cards, featured a storage area where numbers and results were held and accomplished arithmetic functions for multiplication and division, not to mention a variety of other mathematical functions.
Babbage never was able to build his locomotive-sized analytical engine, only ever completing a section of Difference Engine No. 1, a 2,000-part component that was just a fraction of the massive machine that never was.
Tanks offered a show of power during World War II and Adolf Hitler wanted to punch up his strength profile with the largest tank ever created, the Panzer 1000, which he dubbed the "Ratte." These 1,000-tonne, 115-foot-long "Landkreuzers" were put under the care of a submarine builder and were designed to house 40 soldiers encased behind 10 inches of steel.
Siege engines were all the rage for Demetrius I, King of Macedon, around 300 BC. And as you'd expect, the king kept growing his engines larger and larger until arriving at The Helepolis, an armored tower 130 feet tall and 65 feet wide that held multiple armaments, catapults, and nine floors to hold its soldiers.
Plated with iron and sitting atop wheels, mechanical alignments allowed adjustments to the machines inside. The largest siege engine of the time was put into quick action against the city of Rhodes, but they were ready for it, flooding the area Demetrius planned to attack so that when the engine rolled up it got mired in the muddy sewage and rendered the engine a deserted failure.
Explosions so large that they register as one of the largest non-nuclear explosions in history aren't a good way to launch a new rocket. In an effort to get to space, the Soviets designed and built the N1 rocket, made up of 30 smaller engines to power the 344-foot-tall, 6-million-pound rocket.
That wasn't a safe design, it turns out. During the second of four failed launch attempts, the engines exploded so extravagantly that satellites easily photographed the aftermath. Each of the four failed attempts led to the cancellation of the lunar rocket effort in 1972.
This prototype from George Bennie in the late 1920s, called a railplane, used propellers and on-board motors to send the rail machine traveling up to 120 mph above existing slower moving rail.
The 390-foot-long prototype showed off the potential of the proposed lines from Edinburgh to Glasgow and Southport to Blackpool, but the ambition never became reality, leaving the prototype to rust out while Bennie went bankrupt.
If you thought the B-52 was big, you missed out on the 1930 Soviet creation of the Kalinin K-7. With 92 feet in length and a 174-foot wingspan, the Kalinin took seven engines to get it into the air. The only issue was, well, all that air. The first time they tried to fly it, "resonance" issues shook the plane back to the ground. A quick-fix on the tail fell off on the plane's second attempt.
At 186 feet in length, the Lockheed Starclipper was designed to usher in a new era of shuttle design. Larger than any of its kind in the late 1960s, the Starclipper planned to drop its propellant tank and then, upon atmosphere reentry, extend wings to land safely. With payloads 60 feet long and 22 feet wide and able to hold at least 20,000 pounds, the Lockheed design never materialized.