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Monday, December 14, 2015

Reading List: Rocket Ranch

Ward, Jonathan H. Rocket Ranch. Cham, Switzerland: Springer International, 2015. ISBN 978-3-319-17788-5.
Many books have been written about Project Apollo, with a large number devoted to the lunar and Skylab missions, the Saturn booster rockets which launched them, the Apollo spacecraft, and the people involved in the program. But none of the Apollo missions could have left the Earth without the facilities at the Kennedy Space Center (KSC) in Florida where the launch vehicle and space hardware were integrated, checked out, fuelled, and launched. In many ways, those facilities were more elaborate and complicated than the booster and spacecraft, and were just as essential in achieving the record of success in Saturn and Apollo/Saturn launches. NASA's 1978 official history of KSC Apollo operations, Moonport (available on-line for free), is a highly recommended examination of the design decisions, architecture, management, and operation of the launch site, but it doesn't delve into the nitty-gritty of how the system actually worked.

The present book, subtitled “The Nuts and Bolts of the Apollo Moon Program at Kennedy Space Center” provides that detail. The author's research involved reviewing more than 1200 original documents and interviewing more than 70 people, most veterans of the Apollo era at KSC (many now elderly). One thread that ran through the interviews is that, to a man (and almost all are men), despite what they had done afterward, they recalled their work on Apollo, however exhausting the pace and formidable the challenges, as a high point in their careers. After completing his research, Ward realised he was looking at a 700 page book. His publisher counselled that such a massive tome would be forbidding to many readers. He decided to separate the description of the KSC hardware (this volume) and the operations leading up to a launch (described in the companion title, Countdown to a Moon Launch, which I will review in the future).

The Apollo/Saturn lunar flight vehicle was, at the time, the most complex machine ever built by humans. It contained three rocket stages (all built by different contractors), a control computer, and two separate spacecraft: the command/service modules and lunar module, each of which had their own rocket engines, control thrusters, guidance computers, and life support systems for the crew. From the moment this “stack” left the ground, everything had to work. While there were redundant systems in case of some in-flight failures, loss of any major component would mean the mission would be unsuccessful, even if the crew returned safely to Earth.

In order to guarantee this success, every component in the booster and spacecraft had to be tested and re-tested, from the time it arrived at KSC until the final countdown and launch. Nothing could be overlooked, and there were written procedures which were followed for everything, with documentation of each step and quality inspectors overseeing it all. The volume of paperwork was monumental (a common joke at the time was that no mission could launch until the paperwork weighed more than the vehicle on the launch pad), but the sheer complexity exceeded the capabilities of even the massive workforce and unlimited budget of Project Apollo. KSC responded by pioneering the use of computers to check out the spacecraft and launcher at every step in the assembly and launch process. Although a breakthrough at the time, the capacity of these computers is laughable today. The computer used to check out the Apollo spacecraft had 24,576 words of memory when it was installed in 1964, and programmers had to jump through hoops and resort to ever more clever tricks to shoehorn the test procedures into the limited memory. Eventually, after two years, approval was obtained to buy an additional 24,000 words of memory for the test computers, at a cost of almost half a million 2015 dollars.

You've probably seen pictures of the KSC firing room during Apollo countdowns. The launch director looked out over a sea of around 450 consoles, each devoted to one aspect of the vehicle (for example, console BA25, “Second stage propellant utilization”), each manned by an engineer in a white shirt and narrow tie. These consoles were connected into audio “nets”, arranged in a hierarchy paralleling the management structure. For example, if the engineer at console BA25 observed something outside acceptable limits, he would report it on the second stage propulsion net. The second stage manager would then raise the issue on the launch vehicle net. If it was a no-go item, it would then be bumped up to the flight director loop where a hold would be placed on the countdown. If this wasn't complicated enough, most critical parameters were monitored by launch vehicle and spacecraft checkout computers, which could automatically halt the countdown if a parameter exceeded limits. Most of those hundreds of consoles had dozens of switches, indicator lights, meters, and sometimes video displays, and all of them had to be individually wired to patchboards which connected them to the control computers or, in some cases, directly to the launch hardware. And every one of those wires had to have a pull ticket for its installation, and inspection, and an individual test and re-test that it was functioning properly. Oh, and there were three firing rooms, identically equipped. During a launch, two would be active and staffed: one as a primary, the other as a backup.

The level of detail here is just fantastic and may be overwhelming if not taken in small doses. Did you know, for example, that in the base of the Saturn V launch platform there was an air conditioned room with the RCA 110A computer which checked out the booster? The Saturn V first stage engines were about 30 metres from this delicate machine. How did they keep it from being pulverised when the rocket lifted off? Springs.

Assembled vehicles were transported from the Vehicle Assembly Building to the launch pad by an enormous crawler. The crawler was operated by a crew of 14, including firemen stationed near the diesel engines. Originally, there was an automatic fire suppression system, but after it accidentally triggered and dumped a quarter ton of fire suppression powder into one of the engines during a test, it was replaced with firemen. How did they keep the launcher level as it climbed up the ramp to the pad? They had two pipes filled with mercury which ran diagonally across the crawler platform between each pair of corners. These connected to a sight glass which indicated to the operator if the platform wasn't level. Then the operator would adjust jacking cylinders on the corners to restore the platform to level—while it was rolling.

I can provide only a few glimpses of the wealth of fascinating minutæ on all aspects of KSC facilities and operations described here. Drawing on his more than 300 hours of interviews, the author frequently allows veterans of the program to speak in their own words, giving a sense of what it was like to be there, then, the rationale for why things were done the way they were, and to relate anecdotes about when things didn't go as planned.

It has been said that one of the most difficult things NASA did in Project Apollo was to make it look easy. Even space buffs who have devoured dozens of books about Apollo may be startled by the sheer magnitude of what was accomplished in designing, building, checking out, and operating the KSC facilities described in this book, especially considering in how few years it all was done and the primitive state of some of the technologies available at the time (particularly computers and electronics). This book and its companion volume are eye-openers, and only reinforce what a technological triumph Apollo was.

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