At a first glance, a direct high-speed connection between London’s airports doesn’t seem like a terrible idea. Because as the situation stands right now, connecting via rail will take a passenger through the busy zone 1 of central London. Depending on traffic, coach or taxi connections using the road network (while able to avoid central London) still take approximately 1 hour.
So, let’s have a look at connecting the two busiest London airports, Heathrow and Gatwick. Their distance as the crow flies is 25 miles, but a hyperloop connection would probably take between 30 and 35 miles long.
Overground or underground?
Overground is cheaper to build but more expensive if you have to compensate landowners or avoid busy areas and bodies of water. Also, it might be easier to evacuate in case of emergency. On the other hand, going underground is more expensive to build but is more protected from the elements and terrorist attacks. It will also be easier to have a more direct path, which is important for Hyperloop as turns cannot exceed a certain radius.
A hybrid approach seems like the best option if the terrain allows for it.
The Hyperloop, as originally envisaged, can support speeds of over 700 mph (average speeds of 600 mph), which would mean 5-minute trips between Heathrow and Gatwick airports. Even half the average speed means that the trip between airports would be shorter than transfers between terminals within the same airport.
Passenger traffic between the airports is high, so demand will be strong provided the prices are reasonable. One way to keep prices low would be to design a system that has a low cost per passenger. A lower ‘high speed’ means more time to break in an emergency and shorter safety distances between pods/capsules. Another option would be to stack more than one pipeline each way, which might be easier for the overground option to accomplish.
The video below shows the prototype testing of Virgin’s Hyperloop One which reached a top speed of 670 mph:
Hyperloop is a new and untested technology so the cost for such a project is expected to be more expensive than conventional transportation. For reference, here are the costs per mile for other UK transport infrastructure projects:
- Crossrail: £202 million – This is how much the £14.8 billion, 73-mile scheme is costing per mile.
- HS2: £127m – This is the per-mile rate for the 335-mile long, £50bn high-speed scheme, if both its phases are completed, including the £7.5bn cost of the trains.
- HS1: £85m – This is how much the £5.8bn, 68-mile long high-speed rail link was per mile when completed in 2007.
- Channel Tunnel: £302m – What the 31.4-mile tunnel completed in 1994 took per mile to build, with an overall cost of £9.5bn.
Based on the above, one could expect a cost between £300m and £500m per mile, which would mean we’re looking at costs comparable to the Crossrail project.
That would be a tough sell, especially in the whole Brexit financial climate. Many would protest against London getting yet another expensive infrastructure project without benefit to the rest of the country and arguably without benefit to most Londoners as airport transfers are usually not applicable to them.
- Sell it as a solution to the controversial expansion of Heathrow Airport. Why build an unpopular terminal and runway at Heathrow, when you can build it at Gatwick or Luton, and still have people use Heathrow for connections or even complete the check-in and security check there, and only travel to the other airport for embarkation.
- Promise to add stops that would serve commuters to/from London. If Heathrow is only 15–20m (non-stop) from Paddington station, a 10–15-minute Hyperloop connecting trip would greatly benefit those living around those stops and would also work well with Crossrail.
- Sell it as a prototype for an expansion towards the North and create as many jobs as possible. In this case, however, the project would probably make HS2 redundant – I’m not sure if that’s a good or bad thing.
- Sell it as an investment in advanced technology, something built in order to help Britain gain a competitive edge in a post-Brexit environment. It goes without saying that in this case, the contract must go to either a British company and the public sector will have to be heavily involved.
Most of these options seem unlikely to me. The most feasible scenario would be to wait. Once Hyperloop is an established technology, the costs are going to go down and the project would be much more appealing.