A nice idea... but a non-starter

While motorists in Britain pay a princely sum for petrol, the great gas guzzlers that fill our skies get a much better deal.

Despite millions of litres of aviation fuel being burned in the skies every day, none of it is taxed, meaning the airlines are in an enviable position compared to motorists.

For every 80p litre of petrol the ordinary motorist buys, the Treasury siphons off 49p. For airlines which have to buy 200,000 litres to fill a jumbo jet, this represents quite some saving.

31p for you, 49p for them, 31p for you, 49p for them

The situation has been highlighted by a report from the Institute of Public Policy Research, which labels the discrepancy the "aviation tax subsidy".

Efforts to limit emissions of carbon dioxide are being undermined by the expansion in air travel and the pressure for more runways at London airports. Taxing aviation fuel is one way this could be addressed, it says, adding that it could also bring in �6bn a year in tax revenues.

But does the discrepancy give ordinary motorists an opening to take advantage of the tax breaks afforded to airlines? After all, you don't have to stick to super unleaded to get you from A to B.

For instance, last year police in Wales found drivers had been using chip fat instead of diesel to run their cars. In Japan, old tempura fat is recycled into petrol pumps. A Philadelphia turkey factory is making its waste fat into fuel. And even Asda vans in the UK have been converted to be part fuelled by chicken fat.

The number of people flying from UK airports is forecast to almost treble by 2030... the benefits must be weighed against the environmental costs, including noise, air pollution and climate change IPPR report

But the dream of nipping down to Heathrow to fill up the car on legal duty free fuel is destined to remain just that.

Aviation fuel in petrol engine cars is a non-starter - almost literally. Its poor octane rating means it would pre-ignite in the combustion chamber of a car - a process known as "pinking" - badly damaging the engine.

Diesel drivers could in theory have more luck since "pinking" is part of what helps drive a diesel engine. In the past motorists have mixed kerosene - a heating oil similar to aviation fuel - with diesel.

And plenty of military vehicles are tuned to accept aviation fuel because supplies of high-grade diesel cannot be guaranteed in combat.

Dangers

But it is a compromise. Today's car engines are finely tuned to get the best in power and fuel economy. Sticking a few litres of aviation juice in your tank would undo much of that good work.

Sustained use [of aviation fuel] would also wear out the engine relatively quickly, says Dr Calvert Stinton, a fuels expert. Aviation fuel lacks the "lubricity additives designed to maximise the life of fuel pumps in modern diesel engines".

Even if you were willing to accept the consequences, there's another block: it's almost impossible to get hold of. Because of the huge amount of fuel planes burn, it would be impractical to transport the stuff by tanker.

Oil interests not believed to be under threat

Instead it is delivered to airports through underground pipes and, because it is "bonded" (tax-free) rigorous checks are kept on its use. Of course, it is also illegal to run your Ford Focus on aircraft fuel.

Could a fairer compromise be to level the playing field by forcing airlines to pay tax on their fuel?

Agreements

Both the government and the European Commission have backed down from such a move, knowing it would need the renegotiation of hundreds of bilateral treaties.

But even if tax were imposed on fuel in the EU, it would be easy for airlines to pop over to the nearest tax-free country to fill up. The result is a Catch-22 where no country wants to make the first move.

So, while Europe has abolished duty free for passengers on all internal flights, there's no sign of the airlines suffering a similar fate.

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Your comments so far:

It as been obvious to many people for a long time that there should be a carbon tax on all fossil fuels, whether used for flying, driving, electricity generation or heating. The stumbling block is not bilateral treaties but the USA whose government is blighted by people who think belief in global warming will reduce their personal profit.
Malcolm Scott, UK

This is madness. Taxing airlines isn't going to reduce pollution, in the same way that raising petrol prices doesn't keep people off the road. All we end up doing is paying more.There is no alternative to air travel, so when fuel costs shoot up who will pay? We will.
Tony, UK

What about the tax passengers already pay - �63 tax and charges on a randomly selected transatlantic flight and �30 on a European one. Or do we simply want to push struggling airlines out of buisness.
Ray Whitfield, UK

Taxing aviation would just cost the public. I doubt if the airlines would swallow the cost of increased fuel. Instead prices of flights would planes would with the customers footing the bill. There also could be safety ramifications with airlines putting less fuel in planes and having pilots fly more economically.
Scott Armitage, England

I think this story is a bit of a red herring - our government has got around this obstacle for years in the form of departure tax, tiered broadly in line with the length of the route. However, just like duty on petrol and diesel for cars, it still does not stop us travelling.
Richard, UK

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