Elizabeth and I have an interest in nuclear tourism. We are in the San Francisco Bay Area, and we made a trip to see the decommissioned Nike-Hercules missile site SF-88 located near the Golden Gate Bridge, which is run by the National Park Service as a museum.
Nuclear tourism is close to home for us, literally. We live within walking distance of the site of the first nuclear reactor. So far our travels have taken us to Site A and Plot M, land that was the old Argonne National Labs. It’s actually a beautiful hiking area, and we’ve been considering having a picnic with friends there. (How many people can say they’ve had a picnic on top of an actual nuclear waste dump?) Now in all seriousness, it is perfectly safe; I’ve taken a Geiger counter and dosimeters out there and detected nothing beyond the same background radiation one might find anywhere. Additionally, we’ve been to the National Museum of the US Air Force in Dayton, Ohio, which has Bockscar, the B-29 bomber that dropped the Nagasaki bomb, numerous atomic bomb casings (one of these days I need to post the picture of Elizabeth and me posing next to a Mark 41 thermonuclear bomb), and pretty much every ICBM the Air Force has deployed, along with a Minuteman launch capsule trainer.
So, Nike-Hercules, and its predecessor, Nike-Ajax…. This is an engineering wonder of 1950’s era technology. By the time it clears the launcher, it’s traveling at greater than Mach 1 thanks to advances in solid rocket motors. It is a purely defensive weapons system, designed to shoot down any Soviet strategic bombers that manage to slip past the fighters we’d scramble to intercept them. Nike-Hercules was armed with a small nuclear warhead, which increased the likelihood of taking out a bomber formation. It consists of an underground magazine that holds the missiles, an elevator system to bring them to the surface, and four launchers. There’s also an Integrated Fire Control area located farther away from the launchers consisting of vans with consoles, and various tracking radars.
Nike missiles also protected Chicago; there were some on the lake shore near the Point.
So, the problem: Computers in the 1950’s weren’t that small or complex, and employed vacuum tubes. Neither a tracking radar nor the smarts to track and hit a target could be placed in the missile itself. Instead, land-based radars tracked the range, bearing, and azimuth of the enemy bombers as well as the missile launched at them. The missile is flying at more than Mach 2, and the targets are probably going to react and take evasive action. So a ground based computer had to determine steering commands to direct the missiles to the target, which get transmitted to the missile. More accurately, it had to project the path of the target, as well as the missile, into the future to determine where the two would intersect. The solution was to use an analog computer, not a digital one that ran a program. The radar would drive servos, which turned gears and potentiometers. These would continually move, reflecting the positions of the target and the missile. It could then output a time to intercept, and a microswitch would signal the missile to burst. This idea is actually pretty old school. As in, over 2000 years old. I find a lot of similarities between this type of computer and the Antikythera Mechanism, a geared device whose job seemed to be computing the position of the sun, the moon, the planets, and predicting eclipses.
I’ve attached some fun pictures of us with the missiles. And, OK, I couldn’t resist taking one with my finger near the firing switch. And, of course, no trip is complete without a pilgrimage to In-N-Out Burger. Elizabeth is shown in a state of reverence, contemplating the Double-Double animal style burgers and animal style fries we were about to consume.
Ultimately, the Nike missile system became obsolete. ICBM technology won out over strategic bombers, so the threat that Nike was designed to protect against vanished.