Ahh yes, the infamous Thunderf00t "debunking" video. Never have so many Hyperloop myths been created by a single piece of content! I've debunked-the-debunking a half dozen times myself, and it shows no signs of slowing down.
The big problem with his air cannon theory is, pipes are not lossless! Friction and viscous interactions between the entering air and the tube wall will slow down that "shock front" to a highway speed wind in only a couple km. So unless it's so close that the pod can't stop in time (and actually derails at the breach), there should be no loss of life.
As far as thermal expansion, that can be solved with sliding interfaces every few hundred meters. The Hyperloop has switched to mag-lev designs for levitation, so the ultra smooth interior is no longer necessary. There will be some air leakage at the joint of course, but this can easily made up by the pumping stations installed at intervals along the track.
The pressure in the Hyperloop was specifically chosen so that simple mechanical vacuum pumps can be used -- no turbomolecular or cryopumps needed. The Hyperloop runs at 1/1000th of an atmosphere. True "vacuum trains" use vacuums at about 1/1,000,000th of an atmosphere, meaning the pumping is about 1000 times harder (not because the pressure difference is meaningfully different, but because you only get 1/1000th as much air per "stroke" or "cycle").
The Large Hadron Collider uses a harder vacuum still (about 1/1,000,000,000,000 of an atmosphere, and yes that's a trillionth of an atmosphere), which is why LordHumungous's experience mentioned earlier isn't terribly applicable. The LHC is doing something a lot harder than the Hyperloop.
The big problem with his air cannon theory is, pipes are not lossless! Friction and viscous interactions between the entering air and the tube wall will slow down that "shock front" to a highway speed wind in only a couple km. So unless it's so close that the pod can't stop in time (and actually derails at the breach), there should be no loss of life.
As far as thermal expansion, that can be solved with sliding interfaces every few hundred meters. The Hyperloop has switched to mag-lev designs for levitation, so the ultra smooth interior is no longer necessary. There will be some air leakage at the joint of course, but this can easily made up by the pumping stations installed at intervals along the track.
The pressure in the Hyperloop was specifically chosen so that simple mechanical vacuum pumps can be used -- no turbomolecular or cryopumps needed. The Hyperloop runs at 1/1000th of an atmosphere. True "vacuum trains" use vacuums at about 1/1,000,000th of an atmosphere, meaning the pumping is about 1000 times harder (not because the pressure difference is meaningfully different, but because you only get 1/1000th as much air per "stroke" or "cycle").
The Large Hadron Collider uses a harder vacuum still (about 1/1,000,000,000,000 of an atmosphere, and yes that's a trillionth of an atmosphere), which is why LordHumungous's experience mentioned earlier isn't terribly applicable. The LHC is doing something a lot harder than the Hyperloop.