Rolls-Royce has landed a $2.7bn (£1.9bn) contract with budget flyer Norwegian for engines and aftercare support for 19 new planes.
The Trent 1000 engines will power 787 Dreamliner jets and the service package will also cover 11 previously announced aircraft.
The airline, Scandinavia’s second-biggest carrier, also has options for 10 extra planes to run with the Trent 1000.
Rolls Royce shares were trading at 553.7p straight after the news - 0.2 per cent lower.
Norwegian chief executive Bjorn Kjos said the decision further developed his firm’s relationship with Rolls-Royce.
“We look forward to operating aircraft powered by the latest version of the Trent 1000, which sets new standards of performance,” he said.
This order will be welcome good news for Rolls-Royce, which issued its fifth profit warning in less than two years in November.
The £650m downgrade to projections was blamed on slumping demand in the offshore marine market.
Shares in the once-great engineering giant plunged 20 per cent as a result - the second worst drop result since its 1987 float.
Rolls-Royce chief exec Warren East said at the time his group was struggling with too much complexity and high costs.