Farnborough — The contest for supremacy at the year’s biggest aviation expo extended into a fourth day as France’s Airbus and US’s Boeing traded blows with a rush of deals worth $32bn at list prices.

Boeing resumed hostilities at the Farnborough Air Show south-west of London with the announcement of an order for 100 737 Max single-aisle jets from an unnamed buyer valued at $11.7bn based on list prices. That was followed by confirmation of a $2.8bn contract for 10 787-9s from Hawaiian Airlines that saw the US carrier drop an earlier Airbus A330neo purchase.

Airbus hit back with an outline deal from Vietnam’s Vietjet for 50 A321neos — sticker price $6.5bn — and one for 10 smaller A320neos worth $1.1bn, again from an unidentified purchaser.

Airbus capped the morning with a much-anticipated $10bn sale of 34 A330neo wide-bodies to the long-haul arm of AirAsia Group, helping revitalise a programme that’s struggled to make headway against Boeing’s popular 787 Dreamliner.

At the same time, an expected 100-jet single-aisle purchase by the Asian carrier failed to materialise.

The two orders for which the customer was undisclosed extend a trend toward mystery buyers at this year’s trade fair. The secrecy has been attributed to Chinese and Asian customers seeking to avoid stoking tensions in an escalating trade war with US President Donald Trump.

Coming into day four, the tally for the world’s two biggest aircraft makers stood at 780 aircraft, according to Rob Stallard, an analyst at Vertical Research Partners. Airbus had 379 while Boeing was at 401.