The US Navy has quietly added a new super-fuze to the warhead that dramatically increases the ability of the Navy to destroy hard targets in Russia and other adversaries.
The new super-fuze dramatically increases the capability of the W76 warhead to destroy hard targets, such as Russian ICBM silos.
They estimate that the super-fuze capability is now operational on all nuclear warheads deployed on the Navy’s Ohio-class ballistic missile submarines. The new fuze has also been installed on warheads on British SSBN.
“As a consequence, the US submarine force today is much more capable than it was previously against hardened targets such as Russian ICBM silos. A decade ago, only about 20 percent of US submarine warheads had hard-target kill capability; today they all do.”
Before the invention of this new fuzing mechanism, even the most accurate ballistic missile warheads might not detonate close enough to targets hardened against nuclear attack to destroy them. But the new super-fuze is designed to destroy fixed targets by detonating above and around a target in a much more effective way. Warheads that would otherwise overfly a target and land too far away will now, because of the new fuzing system, detonate above the target.
The probability of destroying a fully hardened Russian target with the super-fuzed W76-1/Mk4A warhead atop an American submarine-launched ballistic missile is about 86 percent now versus 50% before.
The surprise to Nextbigfuture was that the land based silos had any survivability from a full nuclear launch. The general assumption that I had was that only the submarine part of the triad had survivability or the air based nukes if the planes could into the air during the first minutes of early warning.
According to the Federation of American Scientists, an organization that assesses nuclear weapon stockpiles, as of 2016, Russia possesses 7,300 total nuclear warheads, of which 1,790 are strategically operational. This is in large part due to the special bomber counting rules allowed by the treaty which counts each strategic nuclear bomber as one warhead irrespective of the number of warheads—gravity bombs and/or cruise missiles carried by the aircraft. The figures are, by necessity, only estimates because "the exact number of nuclear weapons in each country's possession is a closely held national secret.
Russia is setting up nuclear trains again. The Soviet Union had the rail system for a nuclear shell game but it was deactivated in 2005. Russia also has trucks for moving around nuclear weapons. The new nuclear rail system will enable launch from anywhere on the tracks. They will not have to get to special launch locations. China also appears to be adopting rail and tunnel systems for protecting their nuclear weapons.
Nextbigfuture thinks Russia and China are depending upon hardened silos for only a tiny fraction of their operational nuclear deterrent. Shifting from 50% chance of a one shot kill to 86% does not matter that much because the key is knowing where the nuclear weapons are or being able to find and take out mobile submarines, planes, rail and trucks.