Aeronautical Engineers Inc has started work on the second of three Boeing 737-800 freighter conversions for Hainan Airlines at partner facility Grand China Aviation Maintenance Co, reports London's Air Cargo Week.

Work on the aircraft, MSN32603, began on 5 January with GCAM handling modification, maintenance and touch labour. Once completed, the freighter will be operated by Tianjin Air Cargo, Hainan Airlines' sister company, to support expanding cargo operations.

Hainan Airlines currently does not operate freighters, while Tianjin Air Cargo has a fleet of six 737-800 converted freighters. Both carriers are backed by shareholder HNA Aviation.

The AEI 737-800SF conversion provides a maindeck payload of more than 23 tonnes, with eleven full-height container positions and an additional slot for an AEP/AEH.

The third aircraft conversion is expected to begin immediately after completion of MSN32603, further strengthening the airline group's cargo capabilities.