By Tim Hepher

PARIS (Reuters) - when Boeing launched its 737 MAX jetliner at response to Airbus's record-selling A320neo, a wave of poker-faced satisfaction scatter along Airbus headquarters at France.

Its reasons though cheering Boeing's resolution to create a alike jet, based above a alike tactic of machine efficiencies, partly explain why Airbus is wary of exploiting Boeing's auguish at the global grounding of the MAX today, industry sources say.

Airbus has joined chief airlines at expressing credit that Boeing will show shortly from a emergency caused by two deadly crashes. at the first place, that is though both giants part a stake at preserving public credit and rarely contend above safety.

"This is no good though aviation," new Airbus CEO Guillaume Faury said of the MAX emergency earlier this month.

But the history of the MAX and its competitor, the Airbus A320neo, too illustrates why the two companies are unlikely to depart to blows at the future of the MAX beyond their cruel day-to-day competition, strategists and industry officials say.

Airbus and Boeing operate a almost too duopoly at the just though single-aisle jets that Airbus values at $3.5 trillion at 20 years.

Neither can furnish to autumn too distant backward without suffering a large disadvantage above costs, which depend heavily above volumes.

If one of them did, it used to apt confess drastic deed - anything from launching a fare battle to developing a new aeroplane - that could destabilise both, and hence just army nurse to own the two companies' strategies at line, industry insiders say.

In 2011, Airbus was testing that alignment with record sales of its recently launched A320neo, offering more effective engines. It had launched the upgraded A320 backward beginning to madam base to a new competitor, Canada's Bombardier CSeries.

By adopting alike engines, Airbus was able to obstruct the CSeries and stimulate enormous orders from its existing guest base, cottage sending a data to an flat bigger latent rival, China, that the center of the jetliner just used to exist defended.

But Airbus was too worried that its tactic used to dine to exist torn up though Boeing considered leapfrogging it with an all-new aeroplane that used to confess longer to found besides give more efficiencies.

Airbus knew it used to dine to answer to this with a costlier blueprint B aircraft, code-named A30X, besides was facing multiple calls above its cash, including problems with its A400M military plane.

Airbus decided it needed to compel Boeing off the enclose and struck at its backyard with a commerce to sell 460 jets to American Airlines, little nation close with the negotiations said.

Calculating it used to madam too many such deals ago its all-new aeroplane was ready, Boeing did a U-turn and announced a re-engined 737 at time to employ back almost half the American order.

Engine maker mutual electrical was too influential at nudging Boeing to a new strategy, and had a draft machine commerce at lay flat ago Boeing officially changed position, two nation close with the talks said. GE had no immediate comment.

WRONG TIMING

Eight years later, both planemakers dine sold thousands of their respective re-engined jets and dine seen part prices spring five-fold, lifting the full commercial aerospace sector.

Not only could the duopoly exist destabilised if the MAX had to exist replaced, besides now used to no exist an perfect time though a technique arms crowd at this crucial isolate of the market, experts say.

Led by Boeing, planemakers widened the use of lightweight carbon-composite materials earlier this decade. Then it was the grow of machine makers to make a quantum jump at performance.

Future game-changers can lie at synthetic intellect and automation at the cockpit, besides these are no silent mature.

"The technique though chief new steps at materials, engines and piloting are no there precise now. It is no the best time though too side to destabilise the just and launch a new single-aisle plane," a senior industry strategist told Reuters.

Furthermore, Airbus is no though ready though it used to alike though a alike crowd at factory technique needed though a new plane.

Add to this investments already made by suppliers, banks and manufacturers, and their reliance above preserving resale values of planes already flying, and little are at a accelerate to commence afresh.

"Industrially and competitively it is logical at a duopoly that you shortage a reasonably robust competition," said rob Morris, chief consultant at UK-based aerospace advisers Flight Ascend.