|Just say Dr. No.|
Probably one of the most common parlor games is to imagine what you'd do if you had, say, $100 million to spend on a hobby. What would you buy? Where would you go? One man's answer to these questions made the news this week, and it involved a bit of space history. What a perfect excuse to talk way too much about rocket ships from long ago.
ABMA and ARPAIf you'll recall, a while back I talked about Wernher von Braun's missile men and the political obstacles they faced in launching the first American satellite.The Army, Navy, and Air Force were simultaneously developing missile systems, and the expensive research work was becoming redundant. In 1956, Secretary of Defense Charles Wilson ordered the Army to turn over all ICBM development with a range of more than 200 miles to the Air Force.
Here's the problem: von Braun's team at the Army Ballistic Missile Agency (ABMA) would now be limited to regional rockets - - their Jupiter missile was far outside the range of Wilson's 200-mile range limit. ABMA could continue to work on their research, but needed to cripple their performance to be permitted further tests. These restrictions, of course, went out the window when Sputnik launched and the Navy's Vanguard program failed to get an American satellite into orbit. The ABMA team put America's Explorer I satellite into orbit on the last day of January, 1958.
Let's back up a little bit. While all the slicing and dicing of the service branches' rocket labs was going on, the DoD had unofficially created another task force, the Advanced Research Projects Agency (ARPA), whose mission was to figure out what new technologies would be needed by the Space Age military. Through ARPA, the DoD spotted a need for a heavy-lift vehicle that could put giant communications and reconnaissance satellites into orbit. The launch vehicles would need to be able to haul twenty tons of payload into low Earth orbit, or push six tons of payload into interplanetary space. What exactly the military needed with interplanetary missiles wasn't explained.
While all this was getting sorted out between what the Army would be working on and what the Air Force would control, von Braun noticed a loophole in the DoD orders. Secretary of Defense Wilson's directives only applied to weapons, not space vehicles. If von Braun's Army team concentrated on scientific research and not just short-range rocket bombs, they'd be in the clear for building orbital launch vehicles.
A Technological Dead End
As mentioned in an earlier post, the von Braun Redstone was a direct engineering descendant of the German V-2 rocket. The fuel pumps, the tank plumbing, even the thrust steering vanes built into the exhaust plumes were modifications of the WWII-era rocket bombs. There was no easy way to scale this design into a ship big enough to throw twenty-ton spaceships into orbit.
|Heinz-Hermann Koelle, Rocket Guy|
Koelle considered a new, monster 1,600 kN engine Rocketdyne was working on called the E-1. The E-1 was being designed for the Air Force Titan I missile, but Rocketdyne was having problems getting the E-1's fuel pump to work right. The Air Force changed their mind due to the development delays and went with an Aerojet General engine for the Titan instead.
Although Koelle liked the E-1 design, the delay in engine development didn't work any better for him than it did for the Air Force Titan project. Koelle began looking for other options.
While Koelle was trying to find a solution to the engine question, the Army decided to hand off large rocket development to the newly-formed NASA. ABMA would become NASA's George Marshall Space Flight Center, and the work on the Super Jupiter (now called "Saturn," as the new name meant it was "the next thing after Jupiter") would be a NASA project. All the engines, 'E' and above, would become NASA projects.
Koelle's quest for a quicker replacement for the E-1 on Saturn led him to the Rocketdyne H-1 rocket engine, a smaller (778kN) machine originally designed for the USAF Titan that was close to being tested in development. The ARPA folks told von Braun that ABMA would have to use or lose $10 million in the development budget before the switchover to NASA -- so von Braun and Koelle cobbled together a quick plan to improve the thrust to 890kN, enough for eight engines to match the ARPA requirements for the Saturn I.
Go Big or Go Home
|Saturn IB's under construction. |
Lots and lots of H-1 engines required.
Creating anything more powerful in the Saturn series would require larger, fewer engines. There was no point in chasing the E-1: a 1,600kN engine wouldn't be enough for the missions von Braun had in mind. The von Braun team turned to the next development project in the Rocketdyne catalog: the F-1 engine.
The F-1 was mind-boggling in comparison to all previous engine designs. F-1 was planned as generating not 890kN, or even the 1,600kN of the now-scrapped E-1 - - the F-1 was to provide 8,600 kN of thrust. Lashing five of these monsters to the base of a new rocket would generate thirty-four million Newtons, enough to toss 100,000 lbs of payload out of Earth orbit.
The enormous size of the F-1 magnified the development issues with the engine, primarily with resolving combustion instability problems from acoustic oscillations. Being bell-shaped, just about every rocket engine has specific harmonics that form pressure waves when burning propellant. On the F-1, horrific shuddering at 4khz would cause the fuel not to just burn, but to detonate inside the engine bell, destroying the whole mechanism in a sudden explosion. Huntsville engineers took seven years to figure out how to cancel out the oscillations, going so far as to set off bombs of C4 explosive inside the engine bell after ignition to see if their modifications were effective.
"Look at that Rocket Go!"
When the F-1s were finally cleared for flight, they were checked out in an "all-up" test launch of what was now called the Saturn V rocket, launching on the unmanned Apollo 4 mission of November 9, 1967. News media were present and were stationed at the new launch complex 39A, located on Merritt Island.
Walter Cronkite, the veteran quarterback of CBS News coverage in all things space-related, was in a portable trailer three miles from the launch site. He'd seen just about every manned launch at Cape Canaveral, and as a newsworthy event, this ranked as yet another routine unmanned test, though of an unusual size. As the countdown clock clicked to 0:00, Cronkite wondered if the giant beast would make it off the pad.
Watch this video of the launch to hear Walter's first impression of the largest sound made by man that was not an atomic bomb:
The sound was unearthly. The sight of a building thirty-six stories tall rising into the sky and passing through the speed of sound was almost impossible for the mind to grasp. Yet, there it went, and the vehicle to take men to the Moon was ready.
|Mandatory illustration of every Saturn V launch.|
Twelve Saturn Vs would head off the pad after Apollo 4 for the next six years, tossing 24 men to the Moon. The final launch of a Saturn V would be the liftoff of Skylab, America's first space station, in May of 1973. Although the destinations of the payloads were varied, all the 65 F-1 engines that powered the Saturns ended up in the same place: the bottom of the Atlantic Ocean. The first stages of the Saturn V rockets weren't reusable, so the F-1s remained in their watery graves for the past 40 years.
A Treasure HuntAnd then, Amazon.com founder Jeff Bezos decided he wanted to collect a few of the F-1s at the bottom of the Atlantic. Specifically, Bezos wanted to track down the engines that launched Apollo XI into space.
Mission AccomplishedNone of these difficulties seemed to deter Bezos. He and his extremely expensive crew of submarines scanned the ocean floor for months, finally returning radar images of twisted metal almost three miles underwater. Here's a look at what they found:
|A piece of space history.|
Smashed, but recognizable, Bezos's team discovered dozens of F-1 parts and chunks on the seabed. The crew hauled several up to the ship and brought them back to dry land for identification and restoration. So far, the team hasn't been able to identify complete serial numbers to tie the engines to a particular flight. Federal law dictates that all spacecraft equipment remains the property of NASA, but an agreement between Bezos and the space agency indicates that his expedition will be able to retain at least one F-1 engine for the Seattle Air & Space Museum, conveniently located in the Amazon HQ's back yard.
I've read online discussions where some believe this expedition was a colossal waste of money. My feeling is: it's Bezos's money to waste, and if his collection inspires the next generation of space explorers, what's not to like?
|The author with an F-1 engine. I'm 6' 1".|