LONDON — Japanese leasing firm SMBC placed a firm order for 115 Airbus A320 family aircraft on Tuesday.

The deal, worth $11.8 billion at list prices, is the largest single-aisle order ever placed by a lessor. It is split between five A320ceo, and 110 A320neo jets. Powerplants will be chosen at a later time, said SMBC CEO Peter Barrett.

The first of the ceo airplanes will arrive in 2016, with its first neo jets coming in 2017. The last of the order will be delivered in 2022.

The order also pushes the program past its 3,000th firm order, a major milestone. Airbus Chief Operation Officer, John Leahy, said that delivery slots for the jet were becoming “extremely tight”.

SMBC currently operates a fleet of 350 aircraft, including existing A320 models.

Barrett remained confident his firm could place such a large number of jets. He pointed to the high demand for single-aisle jets, a trend that is not expected to ebb any time soon.

As to any A330neo orders for SMBC down the road, Barrett said he was pretty tied up with the A320 order. Though he added that the future “bodes well.”