Sky Aircraft Maintenance (SAM) plans to break ground this spring on a 60,000-sq-ft. expansion of its presence at Davidson County Airport (KEXX) in Lexington, North Carolina, to meet MRO demand for the legacy light- and mid-size business jets it specializes in. 

A member of the Sky Aviation Holdings group of companies based at Pompano Beach Airpark (KPMP) in Florida, SAM provides avionics, maintenance, and inspection services as well as interiors and parts sales for Beechjet 400A, Hawker, Learjet 60 and Cessna Citation-series jets. The expansion builds on a 12,000-ft. facility SAM opened at KEXX in 2020.

“Now it’s running just gangbusters,” Sky Aviation Holdings CEO Tom Conlan said of the original facility, which employs 20 people. “We’re out of space.” The demand prompted SAM to acquire a four-acre, 40-year leasehold at the airport for the base expansion, which Conlan expects will open by the fourth quarter.

Service Life Extensions

The maintenance company’s growth, even as the COVID-19 pandemic chilled commerce, speaks to the increased demand during this time for private jet travel and a desire among operators to extend the service lives of older jets through upgrades rather than paying a premium for new aircraft. 

SAM’s sister company, TBO Extension LLC, offers an FAA-certified, 2,000-hr. engine life extension of the Pratt & Whitney Canada JT15D-5 turbofan that powers the Beechjet 400A, Hawker 400XP, Cessna Citation V and Citation Ultra twinjets, adding about 10-15 years of flying time.

The company has applied for a supplemental type certificate (STC) from the FAA and recently signed an agreement with Honeywell/BendixKing to upgrade jets equipped with Primus 1000 avionics, including Cessna Citation Bravo, Ultra, Encore and Excel models, with new digital displays and flight management system.

Beechjet 400A Upgrade

Conlan previously owned and then sold Part 135 charter operator Sky Limo to focus on refurbishing and reselling aircraft. He explained how a curtailed order with Constant Aviation for upgraded Beechjet 400As led him to develop his company’s own STC for a time-before-overhaul (TBO) life extension of the twinjet's P&WC turbofan. 

Constant had planned to retrofit Beechjets with the Collins Aerospace Pro Line 21 avionics system and to extend the engine life. But in 2018, Constant launched a different upgrade program—fitting the Bombardier Challenger 604 with the Collins Pro Line Fusion flight deck.

“I gave [Constant] an order for 10 of those,” Conlan said of the planned Beechjet upgrade. “We were going to make a market in that airplane because I knew them so well from having operated up to 12 of them with Sky Limo. I ended up hiring an engineer from them and we went and created our own [engine] TBO STC. Last year, we sold 21 of them.”

The TBO Extension STC life-extension of the JT15D-5 turbofan includes a hot-section inspection and associated hardware. An engine data acquisition unit from Latitude Technologies is installed to support engine condition trend monitoring.

“The differential is it costs about $330,000 to do what we do versus $1.2 million to overhaul,” Conlan said. “What we’re trying to do is breathe life into these older airplanes. It used to be you could overhaul a JT15D-5 for a hundred grand; now it’s $600,000—a set of blades is almost $180,000 these days.”

Citation Series Avionics Upgrade

TBO Extension’s planned new Skyview 1000 STC upgrade for Primus 1000-equipped Cessna Citation Bravos, Ultras, Encores and Excels replaces the existing DU-870 CRT displays with DU-875 LCD screens and Garmin GPS/nav/comm navigators with dual BendixKing AeroNav 910 touchscreen GPS/FMS/WAAS/LPV units. The system displays synthetic vision and charts and maps and connects wirelessly to carry-on tablet devices.

“It’s an extremely robust system and it’s going to be significantly less than what Garmin charges” for its G5000 upgrade of the Citation Excel/XLS, Conlan said. “Our system gives you WAAS LPV [Localizer Performance with Vertical Guidance], Vnav and the whole shooting match—just about anything you can think of. It’s Bluetooth enabled, so you can file your flight plan, get in the airplane, fire it up and away you go.”

TBO Extension is also developing an STC for a Collins Pro Line 4 avionics upgrade, Conlan said.

“All told, we think there are about 3,000 airplanes that we can affect,” he said. “We don’t think we’re going to get all 3,000, but we think 20% would be a reasonable number.”