[davidmanze]

    I've solved the problem,, give Elon Musk a tinkle (call)   he's got some sort of above ground tunnel thing on the go, it's nice and long and straight..........apparently it's a partial vacuum!!!

 

 

       ......should be good for tele-zoom lens testing!!  

 

 

 

     Errrr..........what is it called????     Hassleloop..........errr..no,........Hyperblad ....errr? 

 

 

     Something like that  ....  Hmmm....it will come to me....now what was it?......