Okay, so Apollo 11 blasted off from the Florida launch pad in 1969 by firing up five Rocketdyne F-1 engines – the big, stonking, bell-shaped bastards sticking out of the bottom of the Saturn V's first-stage booster. Collectively they burned 13 tonnes of fuel per second to generate the more than 3,400 metric tonnes of thrust needed to loft Apollo 11 up to an altitude of 67km and a speed of 8,300km/h – at which point the second stage would take over and get the astronauts up to the blistering speeds needed for Earth orbit. The F-1s did the heavy lifting of the Apollo project, struggling for forward motion where the gravity was most intense and the pesky nitrogen cloud we call the atmosphere was at its thickest, getting lesser rockets into a position to finish the job and have their moment of glory. At the time of writing they remain the most powerful rocket engines ever fired (though apparently we'll be launching something even bigger in 2017, so hello if you're reading it from that side of history), and still hold the payload record for hauling the 140 tonne Skylab into orbit.
Anyway, looking into the backstory of this Ahnold among engines, this snippet jumped out at me:
The F-1 was originally developed by Rocketdyne to meet a 1955 U.S. Air Force requirement for a very large rocket engine. ... The Air Force eventually halted development of the F-1 because of a lack of requirement for such a large engine. However, the recently created National Aeronautics and Space Administration (NASA) appreciated the usefulness of an engine with so much power, and contracted Rocketdyne to complete its development. – Rocketdyne F-1, WikipediaHuh. So the USAF had the need for a very large rocket engine in 1955. That's not suspicious at all.
On an unrelated topic, on 1 March 1954, the Americans ran the notorious Castle Bravo nuclear test, their first detonation of a dry fuel Teller-Ulam thermonuclear hydrogen bomb. It was remarkable because it was a fusion bomb – that is, rather than splitting the atom as the Hiroshima and Nagasaki bombs had, most of the energy was to come from fusing hydrogen into helium, hence the term hydrogen or H-bomb. Incidentally this is exactly the same process that makes the Sun shine, so it was quite impressive that the puny Earthlings had worked out way to bring a tiny part of the Sun to life inside their biosphere using languages that were only meant for telling one another where the good bananas were.
The main advantages of fusion were a much cleaner blast (less nasty radioactive fallout) and vastly greater energy yields for the size of the device. The catch was that fusion only becomes possible at really, seriously high temperatures – the kind where it doesn't really matter whether you measure it in Celcius, Fahrenheit or Kelvin, as long as you get the number of zeroes right. No problem, said the physicists at Los Alamos, we already have a device that can generate temperatures like that – the atomic bomb itself! Pack a normal fission bomb in one end of a tube, place the fusion fuel at the other end, a little engineering witchcraft and bam, the fission explosion should compress and ignite your very own fusion reaction. Thus, I view the fusion bomb as the moment where the nuclear weapon community officially crossed over into mad scientist/Bond villain territory, taking the greatest weapon the world had ever seen and using it just to light the fuse on their real bomb.
When that fuse was lit, the scientists shat an almighty collective brick. Thanks to a minor mistake, it turned out their 5-megaton device was actually good for 15 megatons – equivalent to fifteen million tonnes of TNT or, if you prefer, seven hundred and fifty Hiroshimas. Remember that saying about assumptions? The scientists had assumed that the enriched lithium-7 in the bomb would remain inert like normal lithium, not contributing to the end result; instead it had proved all too willing to join the party, like pouring a bottle of water to douse a small fire in the kitchen and finding out, too late, that it was actually nitroglycerin. One second after detonation, the fireball was seven kilometres across, and Castle Bravo became the most powerful nuclear weapon the U.S. ever tested.
And oh yeah, officially, this test was a secret. Somehow.
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| No, that's not a natural formation. That's the Castle Bravo crater. |
The lithium assumption (either a band name or a Big Bang episode, your choice) meant the estimates on the fallout footprint were way off, with the result that Castle Bravo became the worst accidental radiation contamination disaster in U.S. history. Fallout gave residents of nearby atolls radiation poisoning and left their homes permanently uninhabitable. The crew of a Japanese fishing boat also came down with sever radiation sickness, and one of them died. But the test was judged a startling success, so I guess in the end it was all worth it: after a few more tests and development things had happened, the U.S. had a deployable version, the Mark 17 air-droppable munition. And it was implausibly, unfeasibly huge.
This thing would be the primary weapon for the new B-52 bomber, the jet-powered replacement for the "aluminium overcast" itself, the B-36 Peacemaker. Professional nutjob Curtis LeMay (the inspiration for General Ripper) had wrangled the B-36 fleet into something he called "Strategic Air Command" and now had them holding station just outside Russian airspace 24/7, waiting for the go-code from the President. But, you know, planes can be shot down, even ones that can take off from the continental U.S. and bomb any point on the planet. Sometimes it's handy to have options, you know? A nuclear bomber with no crew, no mercy and no brakes – that's the kind of thing that appealed to the kind of cold bright mind that thrived at SAC. Something like a rocket.
But you'd need a really big one.
The timing can't be a coincidence: the USAF puts out a request for a big sexy rocket engine right when they're starting to deploy their first-gen hydrogen bombs? Fat fucking chance. The F-1 was intended to toss Mark 17s at Moscow, I'm sure of it. But then a funny thing happened: in 1954, at the annual May Day parade, the Soviets showed the world a massed fleet of enormous jet bombers that looked perfectly capable of bombing the U.S. – Russian B-52s by another name. And so the American military-industrial complex went into full panic mode and started sucking hundreds of millions of taxpayer dollars out of the system to pour into developing a fleet of high-altitude supersonic interceptors with which to shoot them down, stuff like the F-106 Delta Dart which the pilot could barely see out of, which was armed with a mad weapon, the AIR-2 Genie (fighting fire with fire? A hobby for invalids and children. Come back when you're ready to shoot down formations of nuclear-armed bombers using unguided nuclear-armed rockets).
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| You couldn't make something like the Cold War up. |
Of course, it was all a con. The Russians really did have the bombers – a type NATO had given the reporting name "Bison" – but there was no massed fleet. The same four aircraft had made themselves look like a massive fleet using the oldest trick in the book – circling around unseen and flying overhead again, over and over and over. By the late '50s U2 spy planes were starting to give clues that the real Russian strength lay in missiles, triggering another panic about a so-called "missile gap" and hoovering up even more money to build the Polaris and Minuteman missile systems. The interceptor fleet was palmed off on the Air National Guard.
In the fuss, the mighty F-1 had been abandoned. Nuclear bombs were getting smaller and lighter with every generation, so a heavy lift rocket like the F-1 was seen as an unnecessary expense. Until along came NASA, which even with the unlimited funding they enjoyed in those days was in such an expensive business they had to economise a little, and if that meant taking an off-the-shelf engine from SAC, they'd take an off-the-shelf engine from SAC. And so the F-1 was dusted off and put through its development paces on NASA's dime, and was eventually pointed at the Moon in 1969 for its date with destiny in the mission we call Apollo 11.
It's a sobering thought: the first 168 seconds of greatest achievement in the whole of human history was completed using a device originally designed for mass murder.
I'm glad they found a more noble use for it. Something you can really set to stoner music.
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