Simon Calder: Safe and cheap: a new route to the Caribbean

If today's Caribbean-themed edition inspires you to make connections for the region, you are in luck: the world's best airline is shortly to touch down at an airport near you, or at least an airport served from an airport near you.

Skytrax, which rates airline quality, awards a maximum five stars to six airlines: Asiana of Korea, Cathay Pacific, Kingfisher of India, Malaysia Airlines, Qatar Airways and Singapore Airlines. Yet the world's best airline is none of these: indeed, it scores only three Skytrax stars, placing it in the same constellation as easyJet, Monarch and Aeroflot.

"Best", in my book, begins with safety. Of the five-star favourites, Kingfisher and Qatar Airways enjoy unblemished records. Impressive, but they have operated fewer than a million flights. The world's best airline eclipses every other carrier: more than 15 million departures, flying 2 billion passengers, without a fatality. The record is off the scale. Even when it "totalled" a Boeing 737 that overshot the runway at Burbank in 2001, everyone survived.

The winner is: Southwest Airlines, which celebrates its 40th anniversary next year. And, as I found while researching a book on no-frills aviation, it is one of few airlines – in the US, very few airlines – that is a pleasure to fly.

Part of the enjoyment is financial: booking Boston-Los Angeles for immediate departure costs only $267 (£178) on Southwest, $215 less than American Airlines. But the inflight service is unique.

"Aaaaaah, ooooooh, uuuuuuh," panted Duane Redmond, the lead flight attendant aboard Southwest flight 422 from Seattle to Kansas City. Unlike the average safety briefing, he had already explained how to place the oxygen mask "over that big old mouth and nose of yours", and he was now explaining how to breathe something like normally.

On arrival, Duane sang a song: "We love you and you love us/ We're so much faster than the bus/Come back soon for our hospitality/If you'd married one of us you could have flown for free."

Fun, safety and making money are convergent virtues. Southwest is the only American carrier to have weathered the downturns, scares and shocks of the past 37 years without sliding into loss. Yet the airline is largely invisible to British travellers.

One reason: Southwest flies only domestically. Next, it uses mainly secondary airports; flights to the "Miami Area" touch down in Fort Lauderdale – handily, a leading port for Caribbean cruises. And Southwest is thin on the ground in north-east US, with no flights to, or from, the favourite American airport for Brits: Newark, the New York gateway with links from Belfast, Birmingham, Edinburgh, Gatwick, Glasgow, Heathrow, Manchester, and Bristol (to November at least). But starting in the spring, all that changes.

The reason: Continental, the "home-town" airline at Newark, is to merge with United to form the world's biggest carrier. To reduce its dominance at the New Jersey airport, the amalgamated airline must surrender some slots to rivals (just as BA and American Airlines must hand Heathrow slots to competitors in return for commercial cosiness).

Southwest has picked up 18 pairs of slots each day. The airline has yet to say where it will fly from Newark. But Fort Lauderdale, Nashville and New Orleans, all no longer served non-stop from the UK, are key airports for Southwest. A combination of a cheap flight to Newark plus a $225 return (the standard Southwest fare for a two-hour flight) from there to Fort Lauderdale will take you to your ship and back for under £500.

Stars studied: how the airlines stack up

How to become a five-star airline? Looking at the Skytrax rating, it helps to be Asian: no European nor Australasian carrier makes it to the five-star list. BA, Air New Zealand, Qantas and Virgin Atlantic pick up four stars, as do a couple of surprise guests, Air Berlin and Turkish Airlines.

While the Skytrax ratings are subjective, the title "the world's favourite airline" was strictly numerical when British Airways claimed it in 1983. For a few years, BA carried more passengers internationally than any other carrier. That superlative now rests with Ryanair – which, remarkably, is set to carry as many passengers in this year alone as Virgin Atlantic has carried since its foundation in 1984.

How does (very safe) Ryanair rate in that Skytrax survey? A measly two stars, the same as (not so safe) Cubana, TAAG of Angola and MIAT of Mongolia. Only one airline scores lower: Air Koryo of North Korea.