In the late "70s the Air Force became concered about the inprovements in Soviet missile accuracy and the possilbe damage to our own ICBM sites if Russia decided to conduct a surprise first strike attack against the U.S.  Several methods were under considertion for offseting the Soviet technological improvements.  One idea was to build a number of underground tunnels with missile launchers on tracks that could be moved over a large area such that it would be impossilbe for the Soviets to know where they were with any certainty, thus making it unlikely that a significant number could be destroyed in a first strike attack.   In 1979, I was an Air Force representative on the site in the Arizona desert when the test project was completed.  Below are a number of photos I took while the project was in progress.  Some of the machines in these photos are unique and were built especially for this project.  Fortunately, agreements with the Soviets eliminated the needed for any new missile systems, and in fact, most of our previous ICBM sites have been deactivated.

   
The project area had previously been used as a target practice area and had to be cleared of dangerous debris.

   
A badger inspects work in progress.                             An Air Force general inspects work in progress.

    
A giant air conditioner was used to cool the underground tunnel.  Work started at 6:00 a.m. and stopped at
at 2:00 p.m.  Even so, some tunnel workers still fainted from the heat.

   
A huge cement mixer was used for continuous mixing of concrete when the pouring began.

    
A speedier way of digging.

    
This machine was used to dig the upper, flat bottom, portion of the trench.

    
Dirt is transported away as the trencher progresses.     Completed upper portion of the trench.

    
Second trencher with rounded bottom cutter rides on the bottom of the first trench.

    
Replacable cutting teeth fit into these brackets.            Business end of the second trencher in action.

   
In the trencher driver's seat.                                         Concrete going into the tunnel forming machine hopper.

    
The tunnel forming machine creeps along the tunnel as concrete is poured continuously into the hopper .

    
Concrete tube exits the rear of the macine.                   Finished tunnel.

    
Simulated missile launcher that will be placed in the concrete  tunnel for the test.

    
Tunnel entrance.                                                          Simulated launcher repainted for test purposes.

    
Hydaulic jacks that will elevate the launch tube.           Preparing to put launcher into the concrete tunnel.

    
Marked area where the launcher will come up.           Here she comes!

    
Launcher breaks through the concrete tunnel and emerges upward toward launch position.

        
Simulated ICBM missile launcher fully erected.   Test was a complete success.