Delta Air Lines expects its order for 100 Boeing 737-900ERs to be accretive to its profit and loss statement during the fourth quarter.
Carrier president Ed Bastian made that declaration during a 13 September investor presentation.
"We'll be able to realise maintenance savings knowing where the replacement [for 757s] is going to come from," said Bastian.
Flightglobal's ACAS database shows Delta currently operates 165 757-200s and 16 of the 300 variant.
Bastian emphasised the -900ERs would allow Delta to save considerable costs on 757 maintenance as some of the flying on the 757s is reduced.
He also stressed the 900ERs would be cash flow positive from year one.
Deliveries of Delta's 737-900ERs are scheduled to begin in 2013.