Qatar Airways has agreed to acquire up to eight more Airbus A380s and up to 80 A320neos after last-minute efforts to flesh out a deal at the Dubai air show.
The Doha-based carrier will also have first delivery of all three re-engined A320 variants.
Chief executive Akbar Al Baker sealed the deal for the aircraft after a chaotic scene earlier in the day. He had cancelled a press conference and publicly criticised Airbus at a follow-on event during which Qatar ordered Boeing 777 freighters.
But Al Baker said the order - the firm part of which covers 50 A320neos and five A380s - illustrated the carrier's "confidence" in the airframer.
Airbus put the catalogue price at $6.4 billion.