Below it, wave-tossed waters. And the text: "If you're over the middle ofthe Pacific, you want to be in the middle of four engines." Airbus says thead is just promoting the four-engine A340's "operational flexibility," butin an industry where two-engine planes are common, the ad is also drawingheavy flak. The charge: It plays on the public's safety fears - an industryno-no. Continental Airlines' chief executive, Gordon Bethune, fired off aletter to Airbus's president, Noel Forgeard, to say "how unhappy we are"about the ad.

"You exploit the unfounded fears of the travelling public," wrote Bethune,who was previously a senior executive at Airbus arch rival Boeing Co.

"I was shocked to see that ad," says Tom Horton, vice-president for Europeat AMR Corp.'s American Airlines, which flies two-engine Boeing 777s acrossthe Pacific. Adds a Boeing spokesman: "To infer that one type of aircraft issafer, or another is riskier, is inaccurate and inappropriate." He saysBoeing has "expressed its displeasure" with Airbus but hasn't gotten areaction yet.

Why the fuss? The series of ads, created by Havas Advertising's Euro-RSCG inLondon, began running in early October in aviation trade magazines, as wellas in such business publications as the Economist, Fortune magazine, theFinancial Times, The Wall Street Journal Europe and this newspaper. Theproblem, Airbus critics say, is that aviation advertising normally shunssafety comparisons, as a no-win proposition for all. Accidents can happen toanyone, the logic goes, and all Western passenger jets face the samerigorous certification scrutiny. Start raising safety concerns about oneproduct or airline, and ultimately you raise them for everyone.

But the Toulouse, France, aviation consortium - comprised Aerospatiale MatraSA of France, the aerospace unit of DaimlerChrysler AG, British AerospacePLC and Spain's Construcciones Aeronauticas SA - says the fuss is misplaced.

"It's all about operations," says Michel Guerard, vice-president forcorporate communications, who says he has received positive reactions to thead. "We believe that over certain remote areas, it makes sense to have afour-engine aircraft," he adds. The ad "is not about safety," he says,adding, "We're certainly not trying to inspire fear."

But many industry insiders say Airbus has crossed the line by raising thecomplex technical issue of engines through potentially emotion-laden wordsand images. "This discussion has been held in other circles," such as amongregulators and pilots, says Frank Wade, principal at international aviationconsultants SH&E in Amsterdam. "Pitching to public perception hasn't beendone before so blatantly," he adds.

Twin-engine jets are generally less expensive to fly than comparable-sizefour-engine models, but big two-engine jets must pass stringent safety andreliability tests, such as the Federal Aviation Administration'scertification for extended-range twin-engine operations, or ETOPS. The aimis to ensure a twin-engine plane has the safety and reliability of afour-engine model.

Guerard at Airbus dismisses any controversy, saying different aircraftsimply serve better on certain types of routes. "I don't see why we shouldbe shy saying, `Look, we have four engines and in certain remote areas, it'sbetter to have four engines,'" he says, adding, "I think there is nothingwrong or surprising in this ad." Indeed, Guerard is proud of the ad. "It hashad a lot of impact. If there were an award for impact in aviationadvertising, this would win it."