[00:00] In the history of space, one rocket
[00:02] stands out as an icon not only at the
[00:04] space race but also as the mighty power
[00:07] is symbolized, that one rocket which is
[00:10] still the tallest, heaviest and most
[00:12] powerful ever built was the Saturn V
[00:15] and was designed to take men to the moon
[00:17] and later launched to the first American
[00:20] space station Skylab but if things have
[00:23] been a little bit different back in the
[00:24] 1960s we might have had a different
[00:26] rocket to hang on the bedroom walls of
[00:29] the space fans of the 70s and 80s. In the
[00:32] early 1960s a rocket was designed that
[00:35] made the Saturn V looks small by
[00:37] comparison. This was called the sea
[00:40] dragon a super heavy lift rocket that
[00:43] would have been ten times more powerful
[00:45] with 80 million pounds of thrust
[00:47] compared to the Saturns 7.8 million and
[00:51] that was from just one massive engine. It
[00:56] was designed to lift a payload of 1,100,000 lbs
[00:58] into
[01:01] orbit compared to the
[01:03] 310,000 lbs  of a Saturn V.  This
[01:05] meant but it could have lifted an entire
[01:07] space station into low-earth orbit in
[01:11] one mission. The rocket bell of this
[01:14] single engine would be so large at 75
[01:17] feet in diameter that you could fit the
[01:20] entire first stage of a Saturn V with
[01:22] all five of it's F-1 engines inside with
[01:25] room to spare. So what happened to the
[01:28] Sea Dragon a why didn't it get built. At
[01:31] the time of a design in 1962 it was
[01:34] thought by the 1970s, 80s and beyond
[01:36] thousands of people would be working in
[01:39] space and on the moon even on Mars and
[01:42] as such rockets with huge lifting
[01:44] capabilities would have been in great
[01:46] demand because they would have
[01:48] dramatically lower the cost of getting
[01:50] materials into space. The Sea Dragon was
[01:53] designed by Robert Truax,  a US Navy
[01:56] Captain and rocket engineer. He was one
[01:58] of the pioneers of American rocketry and
[02:01] worked on the Thor and Polaris missiles
[02:03] amongst others.
[02:04] His team debriefed the German rocket
[02:07] engineers at the end of World War II
[02:08] including Verner von Braun who went on
[02:11] to design the Saturn V.  Truax believed
[02:14] that it was complexity that drove up the
[02:17] cost of rockets and not their size. His
[02:20] designs for the Sea Dragon made it very
[02:22] simple yet very large. The Sea Dragon
[02:26] would have been 75 feet in diameter and
[02:29] 500 feet tall, half the height of the
[02:33] Chrysler Building. This type of low-cost
[02:36] super heavy rocket is now known as a big
[02:39] dumb booster due to its simplistic
[02:41] design. Instead of having very
[02:43] complicated turbo pump driven engines
[02:46] like the Saturn's, his were the simplest
[02:48] possible design for a rocket engine. In
[02:51] place of having powerful fuel pumps to
[02:54] push huge amounts of rocket fuel and
[02:56] oxidizer into the engine, he proposed a
[02:58] pressure fed system with a separate
[03:01] liquid nitrogen tank to pressurize the
[03:03] fuel tanks. This would push the fuel into
[03:06] the massive combustion chamber. His
[03:09] engines were literally not much more
[03:11] than the valve to turn on the fuel and
[03:13] the huge engine bell. This would make
[03:15] them not only much cheaper to
[03:17] manufacture but more reliable and much
[03:19] easier to refurbish and reuse unlike the
[03:22] f-1 engines of a Saturn which were left
[03:25] to crash into the sea and be discarded.
[03:27] The rocket would be of a two-stage
[03:30] design the first stage would lift it to
[03:32] a height of 130,000 feet before it
[03:34] separated and then fell back into the
[03:37] sea using drag bags to slow its impact
[03:40] with the water, where it would then be
[03:42] recovered for reuse. Although the design
[03:46] was much less efficient than a Saturn,
[03:48] the overall increase in size made up
[03:51] that shortfall so in theory it would be
[03:53] much cheaper per pound of payload
[03:55] compared to smaller rocket systems even
[03:57] ones the size of a Saturn. However there
[04:00] are problems in making such a huge
[04:02] rocket firstly just transporting the parts
[04:05] let alone the fully assembled version.
[04:07] This together with the 80 million pounds
[04:10] of thrust meant but it could not be launched from land.
[04:13] This amount of thrust would have
[04:15] destroyed any existing launch pad. It's
[04:19] estimated that the noise level at
[04:20] takeoff would have been around 165
[04:23] decibels, five miles away or the
[04:27] equivalent of standing next to a 5,000
[04:29] horsepower top fuel dragster at full
[04:32] throttle. Then there was the exhaust
[04:34] plume this would have been up to one
[04:36] mile long. For these reasons the Sea
[04:40] Dragon would have been launched at sea, hence the name.
[04:42] Not from a floating platform
[04:44] but from beneath the water. Now this is
[04:48] not as mad as it seems and there have
[04:50] been examples of sea launch rockets
[04:52] before and after. In 2002 a low-cost sea
[04:56] launch rocket delivery system called the
[04:58] Aquarius with a very similar design to
[05:00] the Sea Dragon but much smaller was
[05:02] proposed to deliver consumables in to
[05:05] low-earth orbit for supplying things
[05:07] like the space station but failed to
[05:09] get selected. Then there was the US Navy
[05:11] which also did research into floating
[05:13] launch rockets and found that the
[05:15] take-off or smoother and less stressful
[05:18] on the rocket than that of a normal
[05:20] land-based takeoff. And if you're
[05:22] wondering why the water doesn't put out
[05:24] the flames it's because the rocket has
[05:27] its own liquid oxygen supply just like
[05:29] the Rockets that work in space where
[05:30] there is no air and the thrust just
[05:33] blows the water out of the engine bell.
[05:35] In fact the sea makes an excellent
[05:37] launch platform as it's indestructible
[05:40] it requires very little in the way of
[05:42] support systems which makes it very
[05:44] cheap, it also provides excellent shock
[05:47] and noise oppression and even allowing
[05:49] for a slight swell, the density of water
[05:51] helps guide to rock it up in the initial
[05:53] moments of lift off till it the exits of
[05:56] water. As part of a low-cost build and
[05:59] the size of Sea Dragon, it would have
[06:02] been built in a shipyard a bit like a
[06:04] submarine from commonly used materials
[06:07] including aluminium, sheet nickel steel
[06:09] and stainless steel for the engine Bell.
[06:11] It would have then been floated into
[06:13] position and fueled allowing it to sink
[06:15] so that just the top was sticking out of
[06:17] water and it would have been supported
[06:19] by flotation tanks under
[06:21] rocket. one idea was to use a nuclear
[06:24] aircraft carrier to provide the power to
[06:26] electrolyze the sea water to make the
[06:28] hydrogen and oxygen rocket fuel, although
[06:31] the first stage would have been powered
[06:33] by RP1 or Kerosene and oxygen, the second
[06:37] stage was powered by hydrogen and oxygen.
[06:39] Although smaller scale versions called
[06:42] the Sea Bee and the Sea Horse were made to
[06:45] prove that they could be launched from
[06:46] underwater the project came to an end
[06:49] when due to budget cuts NASA's future
[06:52] projects branch was closed. But even if
[06:55] it had had been built it would have been
[06:57] a very short life, it was just too big, there
[07:01] just wasn't enough stuff to be lifted
[07:04] into space to make the economies of
[07:06] scale it promised viable. The technology is
[07:09] still as perfectly valid today as it was
[07:11] in the 1960s and maybe at some point in
[07:15] the future when a large amount of
[07:17] equipment is needed to be lifted into
[07:19] space economically something of a
[07:21] similar scale might find a role once
[07:24] more and as always thanks for watching
[07:27] and please subscribe, rate and share.