From 1983 until August 1992, he served as an executive and director of WestAir Holding, Inc. until the company was acquired by Mesa Air in May 1992.

Gallagher was the major creditor of the then small, Fresno-based scheduled airline in 2000 when it declared bankruptcy.

[6] The airline changed headquarters to Las Vegas and eventually changed its business model of flying older large commercial aircraft from small cities around the US to large leisure destinations (initially Las Vegas, later Orlando, Phoenix, St Petersburg, Fort Lauderdale and other cities).

For instance, in between his time at ValuJet and Allegiant, he founded and had leadership positions at Mpower Communications, a CLEC that went public in 1998.

Drivers Johnny Sauter and Sheldon Creed won the Truck Series championship for GMS in 2016[8] and 2020,[9] respectively.

After the 2021 NASCAR Cup Series season, Richard Petty Motorsports majority owner and Medallion Financial CEO Andrew Murstein sold his stake of the team to Gallagher[10] and the team was renamed Petty GMS Motorsports.