Come Fly With Me crooned Frank Sinatra seductively in the 50s when air travel was still seen by many as an exotic adventure and was undertaken regularly only by the glamorous few. Now it seems almost everyone is taking to the skies. The air transport body IATA estimates that there were about 1.5 billion scheduled flight passengers in 1999 and the number continues to rise inexorably with each passing year.
But while Old Blue Eyes' song is evocative of the carefree jet-set popping off to Capri for some gilded cavorting, the in-flight audience that catches the interest of advertisers is a larger one: business travellers. Economic globalisation has meant that more people are working in jobs that require frequent international travel, a trend that is reflected in the increase of airline frequent-flyer clubs.
This is a prized audience that appeals not only to business-to-business advertisers but also to many consumer brands, due to the high disposable income typical of the category. In order to earn their money, however, most business folk have to work hard - making them a difficult audience to reach.
'Everybody's after the frequent business traveller because they are light consumers of traditional media,' British Airways' media commercial director, Caroline Warrick, says.
'Business people are media-loaded,' Booth Lockett Makin's senior media executive, Ruth Snell, adds. 'They are overwhelmed by messages and become good editors, filtering through them. But in the sky they are a captive audience.'
Snell is enthusiastic about in-flight media and has bought it for several clients. However, many other media buyers remain lukewarm.
The marketing services conglomerate WPP thinks it has real growth potential, however. A few years ago it bought Spafax, one of the leaders in the provision of in-flight entertainment content. Spafax's sales network has almost 50 publishing and airline clients which it claims gives it access to 320 million passengers a year.
'I think it's a very under-exploited medium as you have a captive audience,' WPP's director of strategy, Eric Salama, says. 'People want to communicate and interact to a much greater extent. It's still very much under-developed in the way that radio was a few years back. And in business class, you have some of the most highly sought-after consumers imaginable.'
It would be easy to dismiss in-flight media as a choice between airline magazines and TV. But increasingly, advertisers are adopting multimedia solutions; for example, using parts of their TV ads to refer their audience to further information about a product or service contained in a display ad in the in-flight magazine.
Virgin Atlantic, for instance, sells 4.5 minutes of TV airtime in 1.5-minute breaks before, during and after its daily news offering, which is supplied by Sky. It also offers ad space in Hot Air magazine.
One of the most innovative recent deals Virgin has done has seen the premium lager brand Stella Artois advertise in the magazine and sponsor the in-flight movies.
Yet, Virgin Atlantic Media's head of sales and marketing, Gareth Davies, cautions that airlines cannot afford to bombard their passengers with too many of the wrong kind of commercial messages.
BA's own research has found that 86 per cent of passengers travelling in first and business class look at the TV system. But for appropriate advertisers, the airline likes to offer bespoke solutions that use a media mix that includes not only magazines and TV but ambient options such as seat-backs and ticket wallets. Advertisers including Avis and the Welsh Development Agency have taken a mixed media approach and BA offers advertisers 29 different media opportunities.
'If you reach your target audience in-flight, it does create a kind of global presence for the brand,' OMD's international media executive, Rehanna Lalloo, says.
But Emirates' manager of passenger entertainment and communications, Patrick Brannelly, makes the point that advertisers should be aware that not all business travellers fly business class. On popular business routes, a lot of those flying in economy will also be making business trips.
The nature of in-flight media is changing rapidly due to technological advancements. 'There's a big technology leap around the corner,' InFlight Productions' managing director, Steve Harvey, points out. 'Airlines will abandon the old CD systems in favour of file servers to give audio and video on demand. Passengers will be able to specify what they want and when they want it - that is likely to increase the take-up of in-flight entertainment.'
There is also talk about live satellite TV being beamed into planes. US Airlines Jet and Legend are carrying out trials while Rupert Murdoch's News Corporation has formed a joint venture called the In Flight Network with the aviation electronics company Rockwell Collins. This will provide live television, recorded video, audio, internet and e-mail services to airline passengers, both in-flight and on the ground. Meanwhile, Singapore Airlines, Cathay Pacific and Air Canada are among those carriers experimenting with in-flight e-mail.
However, not everyone is convinced that in-flight internet will be a roaring success. 'There are a lot of hardware considerations that have to be solved,' Airline Advertising Bureau's managing director, John Caldwell, says. 'And then, who is going to pay for this new technology? The airlines? Just because it can be done, doesn't mean it should be done.'
Come fly with me ... and watch me send my e-mails. It lacks the romantic appeal of the Sinatra version, don't you think?