Having grown up in the 80’s, I remember some ridicule around the MX missle system, said to be designed in a “dense-pack” arrangement that would cause incoming missiles to “knock each other off course.”
I’ve always wondered exactly how that’s supposed to have worked… obviously the warheads wouldn’t physically impact each other, so the assumption must have been that the nuclear detonation interferes with the proper function of other incoming warheads. There’s EMP and of course the risk of being physically fried by a mighty fireball.
So my basic question is, what’s the maximum frequency at which I can lob 100KT warheads against one particular missile silo in Minot, ND?
And the follow-on question is… we usually think of nuclear war in terms of the allegedly thousands of warheads being thrown, followed by a return volley… but is there any chance the scale would actually be smaller due to warheads neutralizing one another?
I can’t answer your question about the frequency of “bombardment” but want to point out that the Wiki article on Dense Pack, while concise, explains a fair bit about the underlying assumptions.
Not a factual answer but the Whitley Strieber/James Kunetka novel Warday postulates pretty much exactly this. After the first nuclear salvo, everything (especially command authority) is wrecked and the war goes no further. A great read.
I did read it, that’s one of the books that put the question in my head. Is even remotely possible for a nuclear exchange to be unintentionally limited, even on one side? I’d always thought that each side would get a chance to release everything, and having done so, that everything would function more or less as designed. Was wondering if any degree of ‘nuclear fratricide’ was an accepted cost of business, or if there was any expectation that multiple hits on the same target would function as expected.
The “dense pack” idea for the silos was scrapped as it was thought that the enemy would merely ensure the warheads hit each silo exactly together…
Or delay the warheads to arrive more than 10 seconds apart.
I think that the period could be as short as 10 seconds.
The shockwave travels real quick… Its all over in 10 seconds, including the breath back in. The breath back in is after the fireball has really lifted up and away.
The warheads would not be affected by the heat or radiation of the fireball, but they would be physically knocked about by the shockwave and inward breath, this might affect the steering. However this windage affect would only be at such low altitude the effect of skewed steering is minimal., the warhead is almost at its target anyway.
The whole point of multiple “small” warheads is to distribute the explosive power over a larger area. There’s not much point to having one warhead come down within the blast radius of another warhead; you’d want them spread farther apart than that so as to maximize the damage. That is, unless your goal is to repeatedly hit one particularly hardened target (see below).
And then there’s the EMP. This is maximized by detonating at high altitude; the Starfish Prime test detonated at 250 miles above the earth. But if you’re trying to do mechanical damage to ground-level targets, you want your detonation to be around a mile up. You’ll still get EMP, but a lot less than for the high-altitude detonation.
Additionally, EMP has a greater effect on longer conductors. An EMP will create very large effects on an electrical grid (see Starfish Prime link), which has wires that are miles long. A warhead a few feet long, not connected to anything else at all, and probably carefully shielded against any potential EMP? Not likely to suffer any ill effects.
Not clear how long EMP effects last (although as noted above they probably won’t have much effect on a small, electrically-isolated warhead), but the intense heat of the plasma laden mushroom cloud ring and the supersonic blast wave will have fled the scene (and dissipated to a harmless level) in less than a minute after detonation. Everything on the ground within a few miles of ground zero will still be aflame, but that won’t cause problems for your next inbound warhead, since it will detonate ~1 mile above all that.
So if you’re trying to hit the same target over and over again, go ahead and plan on one warhead per minute until you get bored or run out of warheads, whichever comes first.
The trend toward the end of the cold war was smaller, but much more precise warheads. Instead of dropping the biggest thing you’ve got, somewhere near a missile silo and hope that puts it out of commission, the latest missiles would put the warhead within a few yards of a missile silo halfway around the world. Then, even a smaller warhead would completely disable the silo.
The obvious question was, then - would too many missiles placed too close together cause one to disrupt the other’s accuracy. While a 50-megaton monster might disable a whole field of silos (you hope) a Hiroshima-grade 20 kiloton might not be effictive if it missed by a few football fields.
The questions of accuracy and reliability and volume (and timing) were all a trade-off. There were a lot of theories, but oddly, not practical tests.
ICBM’s may be different but in know several tactical nukes are often intended to be used against one target. It depends on what the user thinks will assure a kill.
Take the case of the Russian Kursk missile sub. It’s armed with SS-19 missiles (110 kiloton warheads if nuke) and designed to take out a carrier task force. Once it gets the message that the US and USSR are at war, it floods it tubes. It will fire four missiles in sequence. The first missile is expected to pick up radar signals from either enemy planes or ships. If it does, the warhead detonates, intended to blind electronics in the immediate vicinity. That way, missles #2, 3, and 4 will have a much easier time searching for the carrier and detonating over her.
But then, a US carrier task force is sure to have a hunter-killer sub on the look out for Kursks. They’ll fire their torpedoes the moment the Russians start flooding their tubes.
Nuclear attack/response has long been a gauged one. Where one replies in kind in a similar scale.
If a few missiles are launched, the national command authority decides what response to reply with, a full scale counterattack or a same/similar scale response. The thinking is always one of non-escalation, just in case there was an accident, act of a madman, etc.
For, no one wanted to fully explore MAD. We both had enough missiles to essentially depopulate the majority of our population centers and make even small towns uninhabitable from fallout.
As for warhead fratricide, the fireball would be a big deal, but a deal breaker/warhead smasher would be the shockwave. Think of a wall of concrete moving faster than sound, eventually settling down to at the speed of sound until it dissipates into something not destructive.
If a warhead slammed into that wall of air, the warhead would be smashed into a non-functional mess.
So, it was well known what velocities the shockwave travel at until it is survivable for a warhead. It was well known what range the shockwave would be hazardous to one’s other warheads and time bombardment to prevent warhead fratricide.
Needless to say, the precise numbers are still classified, lest newcomers to a MAD game gain parity with the other nuclear armed nations.
As for submarine launched nuclear weapons, those were planned for either a second wave attack, assuming a loss of land based nuclear missiles or for response when a massive wave eradicated the national command authority and ground based nuclear deterrents. They could quite literally launch hours, days or even weeks to months after one side was essentially erased from the planet.
As for the concept of the use of nuclear arms in defense of one’s nation, that is the same concept as using a claymore landmine to defend one’s livingroom from an armed intruder.
Yes, it would be effective. But, one’s home wouldn’t be useful for anything after.
The accuracy was tested on the different MIRV dispensers, however one could not perform practical tests, as one would, of necessity, use live warheads and nuclear detonations. That was prohibited by the test ban treaties after we raised the background radiation quite significantly and radioisotopes were found in our food and water supply. It’s only now decreasing by a significant amount.
So, they relied upon modeling, with information acquired from past surface detonations for the timing and volume. For the re-entry vehicle, there were tests to prove each system and its accuracy.
