(FORTUNE Magazine) – Until the Concorde crashed last summer, WPP CEO Martin Sorrell took it once or twice a month, shortening each leg of his London-New York commute by five hours. But after that horrendous news footage, will he fly it again?

"I don't see why not," says Sorrell.

With the Concorde due to resume service this fall, British Airways and Air France surely hope all their customers have such nerves of steel.

Although they haven't given their final word on the crash's cause, investigators believe that three critical events occurred. First, an unusually shaped piece of metal on the runway cut a chunk off a landing-gear tire. The chunk hit the wing, which functions as the fuel tank, setting off a wave motion of the fuel. The rippling fuel burst outward through a weak section of the wing, then caught fire, most likely ignited by a severed electrical cable in the landing gear. The fire caused the supersonic jet to crash.

To keep such an event from happening again, Michelin has developed a more robust tire that's less likely to break apart in such big pieces. Second, wiring in the landing gear is being covered with steel mesh instead of aluminum, reducing the chance that it will be accidentally cut. Last, the planes are being retrofitted on the inside bottom of the wing with a lining of rubber and Kevlar, the stuff used to make bulletproof vests. (Because the inside of the wing is less than two feet high in places, BA had to recruit its smaller engineers for the retrofit task. It took two months to line the wings of the first of its seven planes.)

"If you can stop any one of the three events, the same thing can't happen again," says Mike Bannister, BA's chief Concorde pilot. "If you can stop all three, you multiply geometrically the chances that such an accident won't occur again." BA is spending $3.4 million per plane to retrofit its seven Concordes. On its first test flight, in late July, BA said all systems functioned as expected. It hopes to have three Concordes in service soon, allowing it to schedule two flights a day, from London and New York.

Meantime, BA has been regularly briefing its Concorde fliers, 80% of whom are repeat customers. Last spring BA invited the top 50 fliers in London and New York for a presentation of its safety measures--including a peek into the Kevlar-lined wing. "They were very satisfied with our safety approach," says Bannister.

But they were equally intrigued with the new carpets, seats, curtains, and bathrooms that BA is installing at the cost of $2.8 million per plane. The seats, of ink-blue leather and fabric, are more comfortable, with head and foot rests. The bathrooms have opaque doors, giving them a greater sense of space. The piece de resistance is a new lighting system that "changes to a cool blue wash" when the plane goes through the sound barrier. (Until now, passengers found out they'd reached Mach 1 and 2 by reading a small, lighted sign at the front of the cabin.) "The idea is to signify in a cool, sophisticated way that we've gone through the speed of sound," says a BA spokeswoman. "To make it a bit more exciting."

--Janet Guyon