Business aviation maintenance services provider Jet Support Services Inc. (JSSI) has added a second private-equity partner with a “significant” investment from Genstar Capital, the companies announced today. Details of the investment were not disclosed, but JSSI CEO Neil Book said it will fund the company’s next phase of expansion.

“As we start this next chapter, Genstar is an ideal partner, with a tremendous track record, to support our ambitious growth plan,” said Book, whose family is among JSSI investors that also includes private equity firm GTCR. “My team and I are appreciative for the ongoing collaboration with GTCR, which has been a fun and rewarding partnership since 2020,” he added. 

San Francisco-based Genstar focuses its investments on financial services, health care, software, and industrials. Genstar partners Eli Weiss, Ryan Clark, and Rob Clark said their firm has a rich history of investing across software, insurance, and industrial distribution businesses and will bring that perspective to help JSSI. They added that JSSI is well positioned to further its position in the private aircraft maintenance sector based on its 30-year history in the industry.

This investment follows Chicago-based JSSI’s acquisitions last year of aircraft maintenance-tracking companies Traxall and SierraTrax, and prior to that, GTCR’s investment in 2020.