This year’s air show in Dubai featured an unusual array of upsets, surprises and comebacks as Airbus and Boeing fought over orders, while a new contender from China made its presence felt to challenge the long-standing duopoly.

Local champion Emirates opened the biennial event with the biggest deal by value, ordering 65 additional Boeing 777X aircraft for $38 billion (€32.9 billion). The move to double down on Boeing’s biggest jet surprised many just weeks after the plane maker announced another delay for its market debut.

“Emirates remains frustrated by ongoing delays with the Boeing 777X, but it has to look forward into the 2030s, when it begins to retire some of its larger A380s,” said John Strickland, director of JLS Consulting Ltd. The double-decker A380 is Emirates’ marquee jet.

Airbus, meanwhile, punched back Tuesday after announcing nothing on the opening day. The company secured the biggest upset of the event by winning Flydubai as a customer, an airline that so far had built its fleet exclusively around Boeing’s 737 model.

The Airbus planes offer Flydubai greater flexibility on operating long-haul routes to smaller markets, Strickland said.

The rapid-fire back and forth underscores the high-stakes dynamic of the Dubai show, which has become one of the three primary industry exhibitions – besides Farnborough in the UK and Paris – for big aircraft orders.

Negotiation teams often sit through the night to get deals across the line, and decisions change at the last minute, with transactions that looked secure slipping and accords that weren’t on anyone’s radar suddenly appearing.

Commercial Aircraft Corp of China Ltd, known as Comac, promoted its C919 model for the first time at a show outside of its home region, putting the jet that looks similar to Airbus’ popular A320 family on flying display, where it performed alongside the Airbus A350 and the Boeing 777.

So far, the Chinese model – which relies heavily on western technology such as engines and aeronautics – hasn’t been certified by regulators in Europe or the US, meaning carriers there can’t operate it.

But Comac’s presence in Dubai was a reminder that the days of the back and forth between just two players – with all the twists and turns that the last three days produced – may soon be coming to an end. – Bloomberg