In the history of space, one rocket stands out as an icon not only at the space race but also as the mighty power is symbolized, that one rocket which is still the tallest, heaviest and most powerful ever built was the Saturn V and was designed to take men to the moon and later launched to the first American space station Skylab but if things have been a little bit different back in the 1960s we might have had a different rocket to hang on the bedroom walls of the space fans of the 70s and 80s. In the early 1960s a rocket was designed that made the Saturn V looks small by comparison. This was called the sea dragon a super heavy lift rocket that would have been ten times more powerful with 80 million pounds of thrust compared to the Saturns 7.8 million and that was from just one massive engine. It was designed to lift a payload of 1,100,000 lbs into orbit compared to the 310,000 lbs of a Saturn V. This meant but it could have lifted an entire space station into low-earth orbit in one mission. The rocket bell of this single engine would be so large at 75 feet in diameter that you could fit the entire first stage of a Saturn V with all five of it’s F-1 engines inside with room to spare. So what happened to the Sea Dragon a why didn’t it get built. At the time of a design in 1962 it was thought by the 1970s, 80s and beyond thousands of people would be working in space and on the moon even on Mars and as such rockets with huge lifting capabilities would have been in great demand because they would have dramatically lower the cost of getting materials into space. The Sea Dragon was designed by Robert Truax, a US Navy Captain and rocket engineer. He was one of the pioneers of American rocketry and worked on the Thor and Polaris missiles amongst others. His team debriefed the German rocket engineers at the end of World War II including Verner von Braun who went on to design the Saturn V. Truax believed that it was complexity that drove up the cost of rockets and not their size. His designs for the Sea Dragon made it very simple yet very large. The Sea Dragon would have been 75 feet in diameter and 500 feet tall, half the height of the Chrysler Building. This type of low-cost super heavy rocket is now known as a big dumb booster due to its simplistic design. Instead of having very complicated turbo pump driven engines like the Saturn’s, his were the simplest possible design for a rocket engine. In place of having powerful fuel pumps to push huge amounts of rocket fuel and oxidizer into the engine, he proposed a pressure fed system with a separate liquid nitrogen tank to pressurize the fuel tanks. This would push the fuel into the massive combustion chamber. His engines were literally not much more than the valve to turn on the fuel and the huge engine bell. This would make them not only much cheaper to manufacture but more reliable and much easier to refurbish and reuse unlike the f-1 engines of a Saturn which were left to crash into the sea and be discarded. The rocket would be of a two-stage design the first stage would lift it to a height of 130,000 feet before it separated and then fell back into the sea using drag bags to slow its impact with the water, where it would then be recovered for reuse. Although the design was much less efficient than a Saturn, the overall increase in size made up that shortfall so in theory it would be much cheaper per pound of payload compared to smaller rocket systems even ones the size of a Saturn. However there are problems in making such a huge rocket firstly just transporting the parts let alone the fully assembled version. This together with the 80 million pounds of thrust meant but it could not be launched from land. This amount of thrust would have destroyed any existing launch pad. It’s estimated that the noise level at takeoff would have been around 165 decibels, five miles away or the equivalent of standing next to a 5,000 horsepower top fuel dragster at full throttle. Then there was the exhaust plume this would have been up to one mile long. For these reasons the Sea Dragon would have been launched at sea, hence the name. Not from a floating platform but from beneath the water. Now this is not as mad as it seems and there have been examples of sea launch rockets before and after. In 2002 a low-cost sea launch rocket delivery system called the Aquarius with a very similar design to the Sea Dragon but much smaller was proposed to deliver consumables in to low-earth orbit for supplying things like the space station but failed to get selected. Then there was the US Navy which also did research into floating launch rockets and found that the take-off or smoother and less stressful on the rocket than that of a normal land-based takeoff. And if you’re wondering why the water doesn’t put out the flames it’s because the rocket has its own liquid oxygen supply just like the Rockets that work in space where there is no air and the thrust just blows the water out of the engine bell. In fact the sea makes an excellent launch platform as it’s indestructible it requires very little in the way of support systems which makes it very cheap, it also provides excellent shock and noise oppression and even allowing for a slight swell, the density of water helps guide to rock it up in the initial moments of lift off till it the exits of water. As part of a low-cost build and the size of Sea Dragon, it would have been built in a shipyard a bit like a submarine from commonly used materials including aluminium, sheet nickel steel and stainless steel for the engine Bell. It would have then been floated into position and fueled allowing it to sink so that just the top was sticking out of water and it would have been supported by flotation tanks under rocket. one idea was to use a nuclear aircraft carrier to provide the power to electrolyze the sea water to make the hydrogen and oxygen rocket fuel, although the first stage would have been powered by RP1 or Kerosene and oxygen, the second stage was powered by hydrogen and oxygen. Although smaller scale versions called the Sea Bee and the Sea Horse were made to prove that they could be launched from underwater the project came to an end when due to budget cuts NASA’s future projects branch was closed. But even if it had had been built it would have been a very short life, it was just too big, there just wasn’t enough stuff to be lifted into space to make the economies of scale it promised viable. The technology is still as perfectly valid today as it was in the 1960s and maybe at some point in the future when a large amount of equipment is needed to be lifted into space economically something of a similar scale might find a role once more and as always thanks for watching and please subscribe, rate and share.