At a time when U.S. airlines are jettisoning food and frills to cut costs, two of Europe's leading airlines are loading up on luxury.

British Airways and Air France have campaigns under way to overhaul lucrative first-class accommodations, which have lost some of their luster as airlines around the world have improved business-class service. The blurred distinction between the two premium grades has prompted many former first-class customers to switch to the far cheaper business class ($3,729, compared with $6,612 for a first-class round-trip London-New York ticket on British Air).

``The people who fly first class are very product-sensitive,'' says Guy Kekwith of Lehman Brothers International, ``and it's important that consumers recognize that this really is a first-class service that's differentiated from business class.'' And that's why British Air turned to old sea hands to design its new first-class cabins. After all, who better than a designer of yacht interiors to maximize the use of tight quarters?

In a project that throws traditional aircraft design overboard, the London industrial-design firm Design Acumen, known for its work on expensive boats, has devised a herringbone-shaped configuration for British Air's new ``individual cabins'' in first class. The new service will be introduced this month and does away with regimented rows; instead of staring at the back of the person in front of them, passengers in most of British Air's 14 first-class cabins will face at a subtle angle toward the window _ and won't have to look at fellow passengers at all.

``Let's face it,'' says Ian Dryburgh, Design Acumen's managing director, ``the softly sculpted shape of a jetliner is closer to a yacht, and the nose of a (Boeing) 747 is similar to a boat, with the two sides converging gently toward each other rather than running in parallel lines.'' He adds: ``Even the cabin dimensions are similar. A first-class airplane cabin is 30 to 35 feet long, and 15 to 17 feet wide. This boat has about a 15-foot beam (maximum width), so the main cabin of the boat is about the same size.''

As in a yacht, fixtures in the new first-class cabins serve multiple purposes. The seat folds into a fully flat bed, while the table is designed with both eating and working in mind. In addition, there is a special folding ``guest seat'' _ similar to a taxi's rumble seat _ so two people can enjoy a private meal together; the guest seat becomes part of the bed when the passenger seat is folded flat. British Air has registered the cabin design under seven patents.

For British Air, the new first-class cabins are a major part of a 115-million-pound ($176 million) investment in its premium services, while Air France is spending 600 million francs ($120 million) for a remake that includes fully reclining seats, onboard bars, increased leg room and a slick advertising campaign that's already won awards. (In one television commercial, a passenger drops his false teeth into the water glass of an astonished stranger sitting beside him; an announcer intones that such an intrusion wouldn't occur in Air France's new first-class cabins.)

``What's really important to people is their space,'' rather than a few extra food-and-drink treats, says Rosel Schmengler of Air France's marketing department.

Air France's new first-class arrangement has two seats (which become beds) beside each other, but with a movable divider so passengers can say au revoir to their neighbor if they choose. ``It's very French that when you have a meal you have a chat with the person next to you, even if you're not traveling with them,'' says the Air France marketing official.

Air France began its new service this autumn on routes to North and South America and Asia. Based on early experience, the idea of a private bed is a real hit: ``We've found that even on short daytime flights (such as Paris-New York) people want to take a nap, even if it's just for one or two hours,'' Ms. Schmengler says.

Across the Channel, the complexity of a first-class overhaul is evident in a visit to Design Acumen's cramped offices in London. The 12-employee firm explored some 150 different designs for British Air's first-class area before settling on the final layout. A thick book of drawings displays many of the rejects.

Putting beds in the cargo hold was rejected as ``too claustrophobic,'' says Mr. Dryburgh, while a proposal for individual fully walled partitions ``was seen as way over the top, too antisocial, a bit like Cell Block H: People want their privacy, but they also want to be part of a whole.''

A sailor since age four, and a qualified yachtmaster at 16, Mr. Dryburgh says that the transfer of design techniques from ships to planes is fairly simple. He points to the cover of a glossy yachting magazine, which is graced by an 80-foot beauty sailing off the coast of Majorca.

The new first-class compartments are fitted in pear-wood veneer and trimmed in silver and gray Ultrasuede and leather. ``It's like in a yacht,'' says the Design Acumen chief. ``You use the woods to soften the environment.''

And you never overstate, he says, because most yacht owners and first-class passengers don't like ostentatious display. ``They want the luxuries, but they want it done discreetly,'' Mr. Dryburgh says. ``The key is how you package it.''