Sky Quest (ERY, Cleveland Hopkins) has retired its sole Hawker 400XP from its Part 135-certified fleet, as revealed by ch-aviation research. US FAA data confirms that MTJ Aviation now owns the jet, although it is not currently listed on their certificate.

N65SQ (msn RK-438) completed its final flight under Sky Quest's 'ERY' code on September 4, 2024, conducting a test flight around Greenville/Spartanburg Donaldson. Now 19.4 years old, the jet has maintained a US registration throughout its operational life and was operated by Sky Quest since 2019, initially as N438BC, before being re-registered in September 2020.

Following this retirement, Sky Quest's charter fleet comprises 22 aircraft, including one Challenger 300, one Challenger 350, two Challenger 605s, one Gulfstream Aerospace G450, one Hawker (400XT) (a sister model of the retired type), one Hawker (850XP), three Hawker 800XPIs, one Hawker 800XPi(2), three Hawker 850XPs, three Hawker 900XPs, and five Learjet 40XRs. Sky Quest provides private jet charter services alongside aircraft management, sales and acquisition support, and jet card membership schemes.

MTJ Aviation's Part 135 fleet consists exclusively of Hawker Beechcraft, with two Beechjet 400As, one Hawker (400XPR), and two Hawker 400XPs. The company specialises in 24/7 medical flights, particularly for organ transplant missions, serving transplant centres nationwide, while also offering private jet charter services.