Follow TV Tropes

Following

Useful Notes / Superior Firepower: Intercontinental Ballistic and Cruise Missiles

Go To

Intercontinental Ballistic Missiles

US ICBMs were under the SAC until 1992, then spent 17 years as part of Space Command before becoming part of the new Global Strike Command in August 2009.

These missiles remain on high alert, but aren't currently targeted on anything. This effectively means that they could launch with 15 minutes warning at just about anything, which serves the US just fine (having the Atlantic and Pacific Oceans for national moats is truly a wonderful thing).

Advertisement:

Although never used in actual combat (Thank God), American missiles have seen plenty of action. Virtually every land-based ICBM system the United States has ever produced has seen variants used for launches into orbital space.

SM-65 Atlas

The US's first successful ICBM.

Had a unique "1.5-stage" configuration; it jettisons two out of three engines during its ascent but keeps the fuel tanks and some other things. Was not silo-launched until the Atlas-F; they explored a variety of screwy basing schemes for their missile. Very quickly allowed the US to gain a massive advantage in strategic missiles over the Soviets; although the Soviets had the first ICBM, the R-7, it was much better suited for use as a space launcher (a variant was the first reliable means to transport stuff to orbit, which is huge) than as an ICBM. Non-storable liquid fuels, huge soft surface launch sites, could only be kept on alert for 24 hours, etc. The Atlas was more practical. (Albeit not very much so - although it was smaller and could use more compact and harder launch facilities, it still used non-storable cryogenic propellants, having to be fueled shortly before launch, and, as mentioned above, wasn't originally silo-based.) Like the R-7, it was used for the first American manned orbital space launches, and became the basis of a very successful and prolific family of launch vehicles (its most recent derivative, the Atlas V, is undergoing conversion to a human-rated system, intended to ferry new capsules to the ISS).

Advertisement:

HGM-25A Titan and LGM-25C Titan II

The Titan I and Titan II were much better as space launchers than ICBMs, really (although the Titan I was never actually used as a space launcher, since the Atlas was already available for the purpose and had essentially the same capabilities, and there were more of them than of the Titan I). Liquid propellants and all; the Titan I didn't even have storable liquid propellants, so it had to be fueled in the silo. They had to have very huge, very extensive launch complexes for some reason. The Titan II carried a large multi-megaton warhead (the 9 megaton W-53 warhead, in the Mark 6 re entry vehicle), which gave the US a useful capacity in that respect. Titan I missiles were retired in 1965, while the Titan II missiles remained in service until 1987 (their high-yield capability allowing the double-digit numbers of Titan II's to remain useful even alongside thousands of Minutemen). Their retirement was accelerated after a Titan II exploded in its silo in June 1980.

Advertisement:

Titan II rockets were also used by the American space program; they launched the Gemini manned spacecraft, and the Air Force would ultimately attach enormous solid-fuel boosters on either side (the Titan III family) to launch heavy payloads. They could've been used for a military space station (the Manned Orbiting Laboratory if you want to look it up on The Other Wiki), but that was canceled in favor of unmanned spy satellites. Those rockets, which were used into the 2000s, also launched the first landers to Mars, the epic Voyager probes on the Planetary Grand Tour, and the Cassini orbiter to Saturn.

LGM-30G Minuteman III

Today, the LGM-30G Minuteman III is the only land-based ICBM in US service; it outlasted its designated successor, the LGM-118A Peacekeeper. It may stay in service as late as 2040. Originally the first MIRV-equipped missile, today it carries a single warheadnote , as well as penetration aids and countermeasures. Solid-fuelled; quick reaction time. The Minutemen have always had digital guidance computers; back in the '60s, the demand for ICs (integrated circuits) that they produced (for the Minuteman II, mainly) drove down the price of ICs and led to substantial improvements, so allowing for the subsequent revolution in microelectronics. Also they were more or less the first modern, mass-manufactured embedded systems anywhere.

Retired LGM-30F Minuteman II missiles are owned by Orbital Sciences, and are used for space launches as the Minotaur I orbital launch system.

LGM-118A Peacekeeper

Originally known as the "MX" (Missile eXperimental), this was a response to the R-36M/SS-18. The US believed it was in a "window of vulnerability", where the Soviets could destroy the counter-force capabilities of the USA (the bombers and the ICBMs) in a first strike, leaving the US only with submarine launched missiles, which weren't accurate to be used against anything other than cities. Therefore they would "win" a nuclear war.

With up to 10 300KT warheads, the Peacekeeper was later planned to be rail-mobile, but there wasn't enough money and the Cold War ended, so they were kept in the silos they were first stuck in (to "demonstrate national will") instead. One of the proposed basing options would have involved several launch silos and a missile train that would move between them, which sounds conceptually similar to Whack-A-Mole.

Now retired from US service, surplus Peacekeepers have been modified by the private corporation Orbital Sciences to become the Minotaur IV orbital launch system.

  • A quick search on Google reveals a romance novel by Vicki Hinze called Lady Liberty, where two agents have to get a briefcase back to Washington, D.C. to stop one of these being launched.
  • One destroys Mount Rushmore in a 1997 film called The Peacekeeper.

MGM-134 Midgetman

Also known as the Small Intercontinental Ballistic Missile, it was the American answer to the RT-23/SS-24 rail-mobile and RT-2PM/SS-25 road-mobile ICBMs. Like SS-25, the whole missile system was carried and could be launched from a wheeled transporter. It was equipped with a single reentry vehicle. Still under development at the end of the Cold War, it was cancelled after the fall of the Soviet Union.

Other Intercontinental Missiles

SM-62 Snark

One of the first long-range strategic missiles in US service, and an intercontinental cruise missile. Formed an unimportant part of the US strategic deterrent for a very brief time until ICBMs made it totally obsolete. Suffered so many test failures that the area of the Atlantic off Cape Canaveral was dubbed "Snark Infested Waters". One Snark was fired from Canaveral aimed at a test range in Greenland. It hit Brazil. This makes Snark the only weapon known to have missed the continent it was aimed at and hit another.

SM-64 Navaho

A North American Aviation offering, from the same people that brought you the P-51 Mustang and the F-86 Sabre. A supersonic intercontinental cruise missile. The project ended up a failure and was cancelled, but the importance of the Navaho in helping along technological development can't be understated.

Four words, Supersonic Low Altitude Missile (SLAM)

Also known as Project Pluto, a Code Name initially for the engines but eventually applied to the whole project. It is probably the nastiest weapon ever seriously conceived. A nuclear-powered cruise missile which would have penetrated Soviet airspace at Mach 3, dropping hydrogen bombs on its unlucky targets. Some questioned whether it would even need a warhead; the thing had an unshielded 500MWt fission reactor (Project Pluto being the codename for the project that was developed under), which would have been rather lethal to everyone within a substantial radius had the thing just flown overhead. Not to mention the fallout plume that the thing would have left, the massive shockwave that an object like that produces flying Mach 3 at treetop level and the sheer noise. The final target was in for a pretty nasty surprise, too, even if the thing ran out of bombs; the thing would really drive down property values wherever it crashed, to say the least. (That's if you bothered to crash it; some strategists proposed the most effective use of the SLAM would simply be to have it criss-cross the target country until it suffered mechanical failure (Which would take quite a while with the nuclear engine!)) Critics dubbed it "Slow, Low And Messy". The US, deciding that the thing was a) too provocative in the Arms Race, b) too dangerous to even test fly and c) regular ICBMs with MIRVs did the job much better, cancelled the project in 1964.

  • An air-launched versionnote  called XK-PLUTO appears in Charles Stross's A Colder War. The missiles are intended as a deterrent and countermeasure in the event that the Soviets awaken "K-Thulu." They get used. They don't work.

How to launch an ICBM

Every missile silo was constantly staffed with two USAF officers, who needed to be in agreement to launch the missile. An order to launch can only come from the President of the United States.

A launch would begin with the transmission of a 35-character code of seemingly random letters and numbers. The commander and the deputy would write down the message in a notebook. Once it concluded, they would compare what they had written, and having agreed they had written the message correctly, they had the authority to open a locked red safe. Each officer had their own combination for a lock, so again, they needed to agree to get in.

The commander would then take out authentication envelopes and find one that had the first two characters of the message. He would open it and take out the plastic "cookie card" inside. If the last five characters of the message exactly matched what was written on the card, then this was a legitimate order to launch the missile.

Also in the message was the ordered launch time, which the deptuy would write down on a clock in the command center, and the unlock code for the missile. For a Titan II, the missile was equipped with two engine nozzles and each was equipped with a line for fuel and a line for oxidizer, a total of four lines for the missile. Each of the lines was attached to a valve when not in use, but one line for the oxidizer was locked. This was the failsafe to prevent an unauthorized or unintentional launch.

The message contained a six-letter code to unlock the missile, which was then input into the system. Six wheels containing sixteen letters gave roughly 17 million possible codes, and only one would work. As a further layer of security, the code was equipped with a tries counter. The crew had only six tries for the code, and on the seventh, the facility would go into lockdown.

With the message authenticated and the missile unlocked, the commander and the deputy would put in their launch keys. The two keys were springloaded and had to be turned within two seconds of each other and held for five seconds to start the launch. This was so that one person couldn't run back and forth, and the keys were also far enough apart that they couldn't reach and turn both at once. This was the final step in which both officers had to be in agreement.

Once the keys were turned, the "launch enable" light came on. From this point on, there was absolutely nothing that the crew could do to stop it. There was no reset button anywhere in the complex. The batteries on the missile would charge, and the onboard guidance computer would run diagnostics. The silo door would then slide open, passing through a radar beam and setting off an alarm. Once the computer finished its checks, the missile would be loaded with fuel and oxidizer. Shortly afterwards, the engines would start, pop the hold-down bolts, and the missile would launch.

From turning the keys to liftoff would take only 58 seconds. Some 30 to 35 minutes after launch, the target would disappear under a brilliant flash.


Top