On Sep 22, 7:29*pm, (Doug Miller) wrote:

The interstate highway system was built for rapid movement of troops and tanks
and guns and bombs. That it happens also to be enormously useful for commerce
and civilian transportation is merely a side effect of its original purpose.

Doug got it exactly right! A major portion of the money to build the
interstate highway system was from the military budget. Many parts of
the system are built to be quickly converted to aircraft runways to
land B-52 size aircraft. For instance the I-5 system between Portland
and Salem is 24" thick reinforced concrete. The rest of I-5 in the
area is not.The highway is straight as an arrow for miles and miles.
All the overpasses are built with single or thin double columns for
support. Not seismically safe at all. All approaches to the overpasses
are compacted earth, not rock. There is a large National Guard
construction group in Salem. I ask you why?

Well, so that in 24 hours or less, the overpasses can be knocked down
and the approaches cleared out and suddenly we have runways for B-52
aircraft. They can't return to their base because it was nuked! There
are no military/industrial facilities in the Willamette Valley, so no
nukes would be targeted there.

Exactly the same situation in the Sacramento valley part of I-5. Check
it out sometime. Same situation in the Omaha NB area. Look at other
freeways designed in the 1950''s and you will see the same pattern.

Of course, today no one thinks this way because the bombers are
obsolete, but the freeways are still ready.

Of course, Ike got this idea from the German Autobahn system. They
were regularly used for operational runways, not just emergency. I
remember driving in the German Alps and wondering at the long straight
stretch of highway with railway right next to it. They even cut away
the side of a mountain to keep it straight. Then I saw the very large
double steel doors on the mountain side. Ah ha! That was a secure
hanger area. Months later I discovered that was the exit to an
underground aircraft factory! They pushed the completed planes out the
door onto the highway, started the engine and took off! All protected
by very steep mountains.

Other interesting things are the old Nike installations around
Seattle. One south of Issaquah has an access road to the top
completely inside the mountain. Another is under one of the community
colleges in the area.

Great thread for metalworking!

Paul in Central Oregon