Singapore-based lessor BOC Aviation has signed a purchase-and-leaseback agreement with US low-cost carrier Southwest Airlines for 10 Boeing 737 Max 8 aircraft.

All 10 aircraft are powered by CFM International LEAP-1B engines.

Robert Martin, chief executive of BOC Aviation, says: “We are delighted to be working with Southwest Airlines once again, building on a long-term relationship that dates back to 2008. This is the sixth major aircraft investment that we have announced this year, which reflects our company’s ability to provide innovative financing solutions for large-volume transactions and our commitment as a global partner to our airline customers.”

These 10 Max jets will add to the 11 737-700s that BOC Aviation already leases to Southwest Airlines, bringing the lessor’s total exposure to the Dallas-based carrier to 21 aircraft, Cirium fleets data show. BOC Aviation bought the 737-700s from the airline in 2009 and leased them back.

BOC Aviation has five 737 Max 8s on lease to three airlines: three aircraft with India’s SpiceJet, one with Czech airline Smartwings, and one with Turkey’s Corendon Airlines. The lessor also has orders for 61 of the -8 variant, plus orders for 10 of the -10 variant. It has no orders for the 737 Max 9, though it does have one -9 on lease to Icelandair.

Cirium fleets data also show that the lessor has eight further orders for the Max, although the variant for these orders is not identified. Seven of the aircraft are to be leased to Icelandair, while one aircraft does not yet have a lessee.