Thursday, 1 May, sees the dawn of an optimistic era for Britain's air travellers. Nothing to do with the election -Thursday just happens to be the day when the summer charter schedules start. There are some causes for hope that this summer will be better than last.

Airtours International has a May Day plan to eliminate delays that some travellers suffered last year, such as the 52-hour wait my colleague Wendy Berliner experienced in Orlando. Airtours is keeping a plane on standby at Manchester airport from 1 May. The aircraft will be fully crewed, ready to take off if other planes "go technical".

Its big rival, Britannia Airways, says it has operated a back-up plane for the past four years. Britannia has chosen International Workers' Day, 1 May, to ditch its long-established Royal Service in favour of a new, classless (if that is not a contradiction in terms) "360" class. Also on Thursday, AB Airlines opens a new route to Portugal: cheap flights from Gatwick to Lisbon.

These are mere silver linings compared with the forbidding cloud on the horizon: the new airport tax being introduced in Spain. Our most popular package holiday destination has imposed a tax of 150 pesetas on travellers. The amount itself - less than 70 pence - is trivial when compared with our Air Passenger Duty of pounds 5 or pounds 10. But Britain's departure tax is an example of how politicians see travel as an easy target: APD is set to double in November, whoever wins the election.

The new tax is the thin end of a potentially expensive wedge: how long before the government in Madrid sees the opportunity for tapping the 10 million British visitors each year for a bit more cash? The levy is all the more galling because, as older readers will recall, Spain dispensed with its 50 peseta tourist tax soon after the mass market holiday industry began 30 years ago.

According to one travel company, the true level of Spain's departure tax is not 70p, but pounds 5.

The tour operator Unijet has announced it will henceforth quote prices for seats on its charter flights exclusive of tax. Nigel Jenkins of Unijet says the company has taken this step "in order to create a level playing field with scheduled airlines, who have refused to include taxes in their pricing. From a marketing point of view we've been at a disadvantage."

Up to a point, this is fair enough: it is important for the traveller to compare like with like. Ideally, all fares would be shown inclusive of tax, as they are for almost anything else you buy. But since the two airlines that dominate the flight market to Spain, British Airways and Iberia, choose to advertise fares without tax, it seems reasonable for competing companies to follow suit.

The problem is: how do you define tax? Besides Britain's pounds 5 Air Passenger Duty, Iberia and BA charge only 60p or 70p Spanish tax, respectively. But Unijet adds on a "passenger charge" to make a total of 948 pesetas and rounds the lot up to pounds 5.

Next time I take a Unijet flight, I shall offer to pay for a fiver's worth of drinks with 948 pesetas, adding helpfully: "It's roughly pounds 5." At yesterday's spot rate, I make the charges exactly pounds 4.

A cynic (see picture, left) might point out that presented this way, Unijet's fares could look artificially attractive, but Mr Jenkins refutes this suggestion: "Seat-only sales provide the only opportunity we have to show passengers how much of the cost of a flight goes straight to governments in tax."

The other great event on 1 May is that one of our favourite destinations comes out of hibernation, at least according to a branch of a travel agency chain. This week I conducted one of my regular incognito trawls of travel agents. The mission: to find the best flight, either chartered or scheduled, to Athens in April. One agent said flatly that I was wasting my time: "Greece doesn't open until May".