[wormseed]

No taxes on fuel isn’t a subsidy, there’s a natural race to the bottom on fuel prices because airlines can easily put more fuel in in a cheaper country.

Meanwhile, in Germany and France nearly 30% of the total cost of rail service is directly covered by the government, and it’s still more expensive than flying.

[mschuster91]

> No taxes on fuel isn’t a subsidy, there’s a natural race to the bottom on fuel prices because airlines can easily put more fuel in in a cheaper country.

There is not, simply because the maximum take-off weight is way larger than maximum landing weight - you can't just shuttle around fuel because you can't land the plane when it's loaded. This is also the reason why airplanes have to dump fuel when emergency/unplanned (e.g. due to medical emergency) landing. While the passengers may survive a full weight landing, the plane will incur heavy damage.

[iggldiggl]

> why airplanes have to dump fuel when emergency/unplanned (e.g. due to medical emergency) landing

Though perhaps that's not the best example - for a really urgent medical emergency where every minute matters, an overweight landing would certainly be considered ahead of wasting precious time dumping fuel. Equally, there are a few more other types of emergencies where you'd want to get back onto the ground ASAP even if that means exceeding the maximum landing weight.

> While the passengers may survive a full weight landing, the plane will incur heavy damage.

At least these days, all aircraft certified under Part 25 must be able to land at maximum take-off weight with a descent rate of 6 ft/s (360 ft/min), which is already at the border towards what would be considered a hard landing (at maximum landing weight, planes need to allow a landing with 10 ft/s / 600 ft/min without structural damage).

So of course you still need to consider whether the changed performance characteristics (approach speed, required runway length, climb gradient for go-arounds, etc.) at MTOW will still allow you to land safely in that specific situation, but fear of "heavy damage" is not something you need to consider. You might want to bring the plane down a little even more careful than usual, the brakes certainly have to work harder and maybe the plane needs to be inspected afterwards just to be sure, but otherwise you should be fine.

[gruez]

That's not how it works. Arbitraging fuel isn't as easy as driving to another state/indian reservation and buying cheap gas. Planes have maximum rake-off and landing weights. All that extra fuel you're carrying is freight that you couldn't carry. Planes carrying too much fuel (typically because they're making an emergency landing shortly after take-off) have to dump their fuel to meet their maximum landing weight.

[H8crilA]

It's still a subsidy (if the rail traffic is taxed and not supported by govt), except that it's a weird kind of subsidy that's near impossible to eliminate.

Also not necessarily true, you can't land a big plane with too much fuel.

[alexgmcm]

>airlines can easily put more fuel in in a cheaper country.

Wouldn't you then end up using a lot of the fuel just carrying the extra fuel? This cost could negate the tax savings.