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As far as I’m aware test shots of both us Air Force and navy icbms off the west coast went to Kwajalein atoll. Some other interesting details… Naval icbms hav

by avs733 3y ago

As far as I’m aware test shots of both us Air Force and navy icbms off the west coast went to Kwajalein atoll. Some other interesting details… Naval icbms have star tracking for alignment and correction but land based ones do not. The reasoning is that they are all dead reckoning…which requires knowing the initial location. The silo doesn’t move, but the subs do. Their location is tracked with another inertial guidance system but that adds error, so they use the star tracking. Overall, the inertial navigation systems in modern icbms are not the limited in accuracy. My favorite…there was a lot of pushback inside the us military on investing in increasing the accuracy of naval ICBMs. Doing so was seen as communicating/implying a shift in strategic goal from targeting cities (lower required accuracy) to targeting hardened facilities (higher required accuracy). That was seen as confrontational because sun based nuclear weapons had been generally treated as a second strike capability, but the primary reason to have the ability to target hardened facilities was for a first strike

ceilingcat0 3y ago
From what I recall land missiles (minuteman) does its own alignment while in the silo to give it what it needs to hit that window in space where the RV detaches. There some documentation and YouTube videos depicting the alignment process.
- avs733 3y ago
  Yup. But that’s based on knowing where the silo is, they are less mobile than subs (or trucks or trains). The alignment is all based on dead reckoning from where it started to where it’s going to know where it is, where it wants to be, and how to steer there.
kijiki 3y ago
> there was a lot of pushback inside the us military on investing in increasing the accuracy of naval ICBMs. The book "Inventing Accuracy" covers this in detail. Fascinating historical perspective. https://mitpress.mit.edu/9780262631471/inventing-accuracy/ https://mitpress.mit.edu/9780262631471/inventing-accuracy/
- avs733 3y ago
  This is the citation I should have provided and completely forgot to. The most interesting boring book I’ve ever read.
keepamovin 3y ago
So the confrontational is more because of the perceived shift to offensive ("unprovoked") first strike over "defensive" second strike, rather than any perceived loss of a deterrent second strike capability?
- avs733 3y ago
  As I understood it yes. The ability to disarm the other side at will, and prevent any retaliation against cities, was seen as an more offensive capacity
- keepamovin 3y ago
  Just want to note that the front page top 10 - 15 the last 24 hours or so has been disproportionately full of US government and military related posts. Something must be coming, some big news. BOLO
missedthecue 3y ago
I'm recounting second hand so can't source anything but here is an SLBM test done in 2021 by a sub off of Florida, and it landed in the South Atlantic. So they must have several different ranges, and possibly it's changed over time. https://missilethreat.csis.org/us-navy-test-fires-trident-ii-slbm-5/ https://missilethreat.csis.org/us-navy-test-fires-trident-ii...
- avs733 3y ago
  They have a range in the Atlantic, it’s used for launches from the Atlantic…the French do similar things https://www.thedrive.com/the-war-zone/34043/france-just-test-fired-a-submarine-launched-ballistic-missile-in-the-atlantic https://www.thedrive.com/the-war-zone/34043/france-just-test... Generally the logic is don’t launch on trajectories over land unless you have to. I believe all of the land based is ICBMs are still tested from vandenberg on the (most beautiful section of) California coast near Lompoc for the same reason. Vandenberg doesn’t have any deployed ICBMs, they all fly to kwaj for testing. Same reason nasa/spacex/seemingly everyone but China make it a goal to not have launches go over populated areas.

by avs733 3y ago

ceilingcat0 3y ago

From what I recall land missiles (minuteman) does its own alignment while in the silo to give it what it needs to hit that window in space where the RV detaches. There some documentation and YouTube videos depicting the alignment process.

avs733 3y ago
Yup. But that’s based on knowing where the silo is, they are less mobile than subs (or trucks or trains). The alignment is all based on dead reckoning from where it started to where it’s going to know where it is, where it wants to be, and how to steer there.

kijiki 3y ago

> there was a lot of pushback inside the us military on investing in increasing the accuracy of naval ICBMs. The book "Inventing Accuracy" covers this in detail. Fascinating historical perspective. https://mitpress.mit.edu/9780262631471/inventing-accuracy/ https://mitpress.mit.edu/9780262631471/inventing-accuracy/

avs733 3y ago
This is the citation I should have provided and completely forgot to. The most interesting boring book I’ve ever read.

keepamovin 3y ago

So the confrontational is more because of the perceived shift to offensive ("unprovoked") first strike over "defensive" second strike, rather than any perceived loss of a deterrent second strike capability?

avs733 3y ago
As I understood it yes. The ability to disarm the other side at will, and prevent any retaliation against cities, was seen as an more offensive capacity
keepamovin 3y ago
Just want to note that the front page top 10 - 15 the last 24 hours or so has been disproportionately full of US government and military related posts. Something must be coming, some big news. BOLO

missedthecue 3y ago

I'm recounting second hand so can't source anything but here is an SLBM test done in 2021 by a sub off of Florida, and it landed in the South Atlantic. So they must have several different ranges, and possibly it's changed over time. https://missilethreat.csis.org/us-navy-test-fires-trident-ii-slbm-5/ https://missilethreat.csis.org/us-navy-test-fires-trident-ii...

avs733 3y ago
They have a range in the Atlantic, it’s used for launches from the Atlantic…the French do similar things https://www.thedrive.com/the-war-zone/34043/france-just-test-fired-a-submarine-launched-ballistic-missile-in-the-atlantic https://www.thedrive.com/the-war-zone/34043/france-just-test... Generally the logic is don’t launch on trajectories over land unless you have to. I believe all of the land based is ICBMs are still tested from vandenberg on the (most beautiful section of) California coast near Lompoc for the same reason. Vandenberg doesn’t have any deployed ICBMs, they all fly to kwaj for testing. Same reason nasa/spacex/seemingly everyone but China make it a goal to not have launches go over populated areas.