In article , "Keith Willshaw"
wrote:

"Howard Berkowitz" wrote in message
...
In article , "Keith Willshaw"
wrote:

All built under clay

When were they built? Were nuclear weapons or penetrating PGMs design
consideration?


For the cabinet war rooms no, for Northwood nuclear weapons
were certainly a consideration

While I cannot get into specifics, it's no accident that US continuity
of nuclear operations focuses on getting the NCA (and successors)
airborne. No one makes it a secret that Cheyenne Mountain and Site R
would not stand up to a fUSSR ICBM attack, given both yields and
accuracy. I'd assume the same is true of Northwood.

Incidentally, some studies of a superhardened shelter, intended for the
DC area, have been declassified -- IIRC, they are online in the National
Security Archive at George Washington University. The idea was deemed
infeasible for a nuclear war environment.



I certainly agree they are stable under normal conditions, and, for
that
matter, the German bombing of WWII. I'm not as convinced that 617
Squadron, using the Tallboy, couldn't have broached them, much less if
more modern weapons were used.

Neither am I but thats not the issue. Tunnels arent just
hard to damage they're hard to find, especially in a
closed society

Agreed. Also note that large tunnel complexes become more vulnerable to
advanced detection systems, such as ground-penetrating radar, thermal
imaging, and probably an assortment of other MASINT methods. Silo-sized
shelters -- sure. Hard to find.


And won't have much effect on a modern penetrating or high blast
weapon.

It wasnt suggested it would, however a 100ft of clay or
sandstone, especially if properly reinforces is rather
difficult to penetrate using conventional weapons.

The interim "bunker buster" rigged from old artillery barrels
penetrated
over 100 feet of hardened clay (caliche) in the US trials before
deployment. They never did dig it out.

And how many would you need to collapse 10
miles of tunnel ?

If there's a 10-mile tunnel, it's going to be easier to find. No one
bomb (other than large thermonuclear) is going to take out the system.

But how many exits and ventilation shafts are there? Collapse the
exits, and what's underground is useless.

You may not have seen my earlier post --- substitute "hard rock" for
"granite." For fairly small installations, such as ICBM silos,
high-grade concrete can do -- although the silos themselves are tunneled
into hard rock.

The Syrians cant re-order the geology of their country but they
can still hide stuff in tunnels

Hide, yes. Protect if found, no.



Civilian systems are rather easier to track than military ones
but we may well know about it. That doesnt mean they
couldnt build em though. I suspect any such were built more
with the IDF in mind than the USAF

Depends on size. At some point, the problem of disposing of the
excavation becomes an issue.