Hyperloop | What is the Fifth Mode of Transportation?

August 12, 2013 Tesla Motors /SpaceX Entrepreneur Elon Musk published the alpha design document for Hyperloop.

What Hyperloop Is:

  • A System of Tubes and Pods. At its simplest, Hyperloop is a system of two tubes in tandem, each tube enclosing people-carrying pods traveling in opposite directions. Getting there is only half the fun – you can get back also.
  • A Low-pressure System. Rather than utilizing a near-vacuum, the system would operate at a low pressure. There would still be a “non-trivial amount of air” in the tube. This air could be of varying density along the length of the tubes due to various factors including small leaks due to design penetrations into the tubes for purposes of entry/exit of the people-carrying pods. An alternate pod design carries vehicles as well.
  • Sustainably Self-Powering. Per the design document, “by placing solar panels on top of the tube, the Hyperloop can generate far in excess of the energy needed to operate.” An excess we can live with.
  • Resistant to Earthquakes. The system would be above-ground, built on pylons. The pylons would include 3-axis dampers to allow for movement of the tube. X,Y and Z-axis movements? No problem!
  • Non-disruptive to Those Along the Route. A large portion of the proposed route would follow the existing right-of-way of California’s I-5 between L.A. and San Francisco. Grapevine to I-5 to I-580.

What Hyperloop Isn’t:

  • Teleportation – “which of course would be awesome”. So much for Star Trek.
  • A Vacuum Tunnel. The air pressure inside of the tubes would be “about 1/6 the pressure of the atmosphere on Mars” [ 100 Pascals, or about 0.015 psi ]. In other words the aerodynamic drag would be the same experienced when flying above 150,000 feet. Drag will be approximately 3 orders of magnitude less than at sea level.
  • Supersonic. Cruising speed of the pods would be about 700 mph / 1,130 kph, or about 0.91 Mach. Travel time each way – about 35 minutes.
  • Magnetic Levitation. Although the pod would be accelerated by use of a linear induction motor – which again, is NOT magnetic levitation, the pod would be supported by an air bearing formed from the ambient atmosphere inside the tube. The pod would have multiple ski-like protrusions, air forming a bearing between them and the tube walls.
  • A Long-Haul Solution. According to the design document, for trips such as L.A. to New York “the economics would probably favor a supersonic plane”.  “..more for commuting than vacations.”

Per the document, Hyperloop is an “open design concept, similar to Linux. Feedback is desired from the community that can help advance the Hyperloop design and bring it from concept to reality.”

The design team welcomes feedback at:

hyperloop < at > spacex.com

hyperloop < at > teslamotors.com

Unless otherwise noted, verbiage within quotes is from the design document.

For more information see Tubes and Pods, Concorde Rail Gun Air Hockey, Sustainable Self-Powering.