this is a very interesting thread, because it has got people thinking what makes a train profitable, albeit mostly on the revneue side rather than costs.
First up, exclude freight. The competitive market for freight has done great things for prices in the market, but not for freight company profitability which is, to be blunt, appalling.
Passenger wise, what makes a service profitable?
Obviously it needs high revenue, but then there’s lots of services out there with high revenue, either through carrying lots of passengers, or charging high fares, and ideally both.
However a profitable service also needs low costs. Accurately measuring costs on the railway has always been notoriously tricky, mostly because of high fixed costs which need apportioning. How do you do this? Per train? per train mile? per vehicle mile? per vehicle hour? There’s various options, but infrastructure costs are, effectively, apportioned through track access charges. Then variable costs - some can be apportioned directly, ie staff costs on board and fuel. Some can’t, easily, such as station staff or fleet maintenance.
Put all that together and I suggest you are looking for services that have :
1) high revenue per passenger
2) high numbers of passengers on board
3) low on board costs, ideally DOO and no catering (as this loses money everywhere)
4) high average speeds, meaning high revenue per hour of rolling stock utilisation
5) electric traction for lower maintenance and ‘fuel‘ costs
As others have said, there’s broadly two categories of service that will fit this:
1) Long distance high speed services that operate at capacity at peak time. Avanti from Manchester or the faster LNER services from Edinburgh are likely candidates. The high peak fares will offset the on board staffing levels. Although the costs of the LNER fleet will sorely test the debit side of the ledger. If the 1700 off the Cross is LNER’s most profitable now, it will be less profitable than it was 20 years ago when I was a regular on it, as there’s less business travel now, and it costs more to provide. I’d suggest the 0735 off Piccadilly is favourite.
2) Fast commuter services into London in the morning peak from the outer suburbs that are 12 car and crush loaded on arrival, with limited stops. Usual suspects on the Brighton line will beat those on the SWML as the latter tend to come from distance, only really fill up later in the journey, and have two staff on board. Honorable mention for Thameslink on the MML, with several services in the morning peak delivering upwards of 1500 passengers, most of who have paid some of the highest per mile (and per minute) peak fare prices into the capital, for the price of a driver and some relatively low per mile fleet and infrastructure costs. However, the services all go on to Sussex, and are somewhat emptier. Then there’s the Cambridge fliers, albeit the peak services all start at Kings Lynn, and call at more intermediate stations to fill up. I suspect the 0706 or 0736 from Brighton will have this one.
But then we come to the Heathrow express, if fully loaded. I don’t know if they ever are, nor what the access charges are on the Heathrow branch. But (say) 800 people paying a minimum of £15 one way for a 21 minute journey at most is going to take some beating.
All in, I reckon a regularly busy HEX will have it.