Spirit Airlines remains open to adding a new aircraft type to its all-Airbus fleet, a move that Spirit's chief executive insists would not necessarily erode Spirit's cost advantage.
Robert Fornaro says Airbus's A220 and products made by Boeing remain on the table, and the company has also said it is considering Embraer jets.
"When I was CEO of AirTran we had two fleet types, and we had the lowest cost of anybody in North America," Fornaro tells FlightGlobal on 24 September.
AirTran Airways operated both Boeing 737s and 717s.
Spirit intends to make a fleet decision by the first few months of 2019, Fornaro has said.
The company currently operates 121 Airbus narrowbodies and has orders for another 55, with deliveries running into 2021, according to Flight Fleets Analyzer.
Still unknown is whether Spirit will chose larger narrowbodies with greater range or smaller models like the A220 or Embraer E-Jet.
Fornaro can envision both scenarios in Spirit's future.
The carrier will evaluate the performance of the A321LR and the newer A321XLR, as well as long-range Boeing narrowbodies – types that could possibly allow Spirit to expand to places like cities in Brazil, he says.
"I could see a scenario where we are operating a single-aisle airplane long haul," Fornaro says. "We need to know what the capabilities are."
Conversely, a smaller aircraft like the CSeries, with roughly 130 to 160 seats, could possibly work for operating routes of less than 1,000nm (1,852km) to secondary cities, he says.
"An option for us to consider is, do we want to have an airplane that can do relatively shorter missions," says Fornaro. "We want to design a fleet that creates a lot of optionality."