ST Aero’s fourth-quarter results – in which it claimed new business worth S$780 million ($610 million) for the quarter – shows the Singapore-headquartered company is growing its business by doing more sophisticated modification and conversion work on aircraft.

It is also investing in its flying school in Australia and getting involved in asset management. It has, for example, established a 50-50 joint venture with Wings Capital Partners Holdings to establish a Singapore aircraft leasing company called WingStar.

ST Aero already has an engine leasing business – ST Aerospace Engines – a joint venture with Japanese conglomerate Marubeni Corporation. Its engine leasing business leases CFM56-3, CFM56-5B, CFM56-7B engines. These are the engines that power Boeing 737s and Airbus A320s.

The person behind Wings Capital Partners Holdings is Stephen Hannahs, who was a cofounder and the CEO of Aviation Capital Group, an aircraft leasing company he left at the end of 2012.

Aircraft leasing companies generally focus on having new aircraft in their portfolio, but WingStar says it will focus on acquiring midlife aircraft “for lease, conversion or part out.” It says it will focus on the A320 and 737.

Because of high fuel prices, the value of older aircraft is depressed. But if WingStar buys older aircraft and fuel prices later decline that means – in theory – it could make a good profit, as the value of older aircraft will rise. Also, even if the value of the aircraft continues to decline, it is clear that ST Aero has a strategy to derive value from such older equipment.

ST Aero disclosed in December that it is establishing an aircraft part-out business called Hondo Aerospace based in Hondo, TX, in the U.S., that will start operations in 2014’s first quarter.

WingStar could also generate business for ST Aero’s passenger-to-freighter aircraft conversion business.

ST Aero has introduced a 15-pallet offering for its long-running Boeing 757-200SF freighter conversion program, and says an undisclosed customer recently contracted to convert five 757s with this new 15-pallet offering.

It also says it secured a contract, in last year’s fourth quarter, for interior cabin reconfiguration work on 20 Boeing 767-300s.