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Maintenance, repair, and overhaul


Here are the most popular MRO shops providing services ranging from aircraft paint to engine replacement.

By Shannon Forrest
President, Turbine Mentor ATP/CFII.
Challenger 604/605, Gulfstream IV, MU2B

Pilots who entered the workforce in the past decade have a different perspective than old timers when it comes to aircraft maintenance. In times past, if a pilot experienced a mechanical breakdown, the person who showed up to fix the aircraft fit the stereotypical mold.

The uniform was a set of coveralls complete with a smattering of barely visible stains that reflected the grease, oil, and residual hydraulic fluid that had soaked into the fabric over time. In one hand he held a white styrofoam cup topped off with steaming hot coffee, in the other an unfiltered cigarette.

His lined face and gray hair revealed that this person had replaced a few cylinders on a Douglas DC-3, swung the gear on a Sabreliner, and tweaked the fuel flow on a Rolls-Royce Spey turbofan on a Gulfstream II once or twice.

His tools of the trade were actual tools. Invariable, the mechanic would produce a screwdriver from some unseen pocket and start working the problem. Rare electrical problems were addressed with an ammeter and a flashlight.

Modern aircraft maintenance

Modern aircraft designed around computers have rendered the grizzly old mechanic as rare as the unicorn. In fact, they’re not even called mechanics any more – they’re technicians. In lieu of coveralls, the new age technician wears khakis and a polo shirt, just like the teenager working in the electronics department of the big box stores. His or her primary diagnostic device is an iPad.

The irony is that a new production aircraft tells the mechanic what’s wrong with it, instead of the other way around. It’s a textbook role reversal. Old-fashioned detective work, like finding a frayed wire, has gone by the wayside.

Changing out a line replaceable unit (LRU) or resetting modular avionics unit (MAU) is the fix. The most common solution uttered by technicians these days is “shut it down, remove all the power, wait 5 minutes, and see if that works.”

Lots of times it does. It’s an application of the “Ctrl–Alt–Delete” reset theory made popular in the IT community.

MRO providers

The most ideal situation when it comes to aircraft maintenance is having a combination of “old school” mechanics and modern-age technicians.

The larger maintenance, repair, and overhaul (MRO) organizations have this capability. Those most adept at classic hands-on work tend to gravitate toward the field of structures, composites, and interiors.

Constant Aviation

Constant Aviation serves as an example of what’s possible with the right talent. Its notable accomplishments include Beechjet and Phenom 300 wing replacements, and the world’s first nose replacement of a Embraer EMB-145 and Embraer 170 twinjets.

However, the most interesting feat involved the recovery and return to service of a Legacy 600 involved an midair collision that occurred over the Brazilian jungle on September 29, 2006.

While on a delivery flight from the Embraer factory at SJK (São José dos Campos SP, Brazil) to New York, the aircraft collided with a Gol Linhas Aéreas Boeing 737-800 at 37,000 ft. The 737 was rendered irrecoverable, but the Legacy managed to conduct an emergency landing in Serra do Cachimbo PA, Brazil.

The Legacy sat dormant for 18 months in jungle until the new owners of the aircraft employed Constant Aviation to send a mobile team to recover the aircraft and render it flyable again. Four years later, it was flown to Constant headquarters in Cleveland OH.

Constant has become known as an Embraer guru, but has capabilities that cover a wide range of airframes and manufacturers. While the need to recover an aircraft from a remote foreign military airfield is outside the purview of most owners, aircraft damage that requires fewer intensive repairs is always a possibility.

Minor bumps and scrapes from aircraft movement in and around the hangar and ramp – hangar rash – constitute a common scenario. Sometimes the damage is obvious and instantaneous, and other times the damage reveals itself only later.

On July 3, 2020, a Piper Meridian turboprop veered sharply right and into the grass upon landing at TIX (Titusville FL). The aircraft received substantial damage to the left main and nose gear, damage to the left wing, and wrinkling of the fuselage. NTSB determined the probable cause to be loss of directional control due to the fracture of the steering horn bolts.

When the steering horn bolts fractured at touchdown, the nose of the aircraft turned 90 degrees opposite the runway, which rendered directional control ineffective. The root cause of the bolt failure was damage caused by the aircraft being towed beyond the turn limits at a time prior to the accident.

It could not be determined exactly when the aircraft was improperly towed. There are 2 lessons here – ensure that the tug operator is aware of towing requirements, and be aware that structural damage sometimes occurs irrespective of piloting ability.

Many pilots have flown aircraft that have undergone major structural repairs, and sometimes the aircraft is still flying crooked when released to fly. In other words, it’s just not right. Using a reputable MRO can alleviate this problem.

West Star
West Star Aviation

West Star Aviation represents a conglomerate of MRO entities capable of a wide range of specialties, including sheet metal repairs and composites. Its ALN (East Alton IL) location specializes in maintenance, repair, and refurbishment of Bombardier Challenger and Global Express, Dassault Falcon, Gulfstream, and Textron Citation aircraft, and provides full FBO services.

The company’s GJT (Grand Junction CO) base also offers full FBO services, with 10,500 ft of runway with an ILS, and 304,000 sq ft of office space across 8 buildings. West Star employs 483 full-time employees at GJT. Technicians are trained by the factory, SimuFlite, or FlightSafety.

Specialized structural repairs – especially composites – are conducted in Cedar Hill TX, and are branded under the subsidiary name Dallas Aeronautical Services (DAS). Computer numerical control (CNC) machining capabilities allow DAS to fabricate parts that are damaged or difficult to find – something that’s especially important with the current supply chain disruption in the marketplace.

At this location, highly-skilled experts can perform precision work on thrust reversers, radomes, flight control surfaces, leading edges, and fairings. Two computer-controlled autoclaves can bond composites ranging from carbon-fiber to Kevlar.

Duncan Aviation

Duncan Aviation. The cabin version of the structural mechanic/technician is the cabinet maker. Duncan provides unique interior cabinet design and refurbishment.

The company specializes in hydrographics – a technique that can mimic textures and designs reminiscent of classic (legacy) materials, like wood and leather, although without the structural difficulties inherent in those products.

This offers several advantages to the aircraft owner, including cost-effectiveness and reduced downtime. Paint is an aspect of aircraft refurbishment that requires a specialized skillset as well. When it comes to paint, Duncan Aviation is an accomplished provider in the industry, with more than 200 aircraft painted per year at its 3 facilities.

As any experienced painter can tell you, it’s all in the prep work. Paint requires the right combination of chemistry to adhere and set properly. Duncan’s process involves controlling humidity and heat and using down-draft and cross-draft prep and paint booths.

Professional designers work with the clients to create the perfect scheme, and then Duncan’s 40 years of experience take over in the application phase. Paint and interior design are part art and part science as aircraft owners have grown accustomed to aesthetics as well as functionality.

Western Jet Aviation

Western Jet Aviation. Functionality includes productivity and comfort. It often depends on advanced avionics, cabin systems, and connectivity.

Western Jet Aviation can install, troubleshoot, repair, and engineer avionics and cabin management systems from its VNY location.

Western Jet is the world’s largest independently-owned business jet maintenance facility, with more than 120,000 sq ft of space, and is considered a Gulfstream specialist.

In addition to the aforementioned structure and interior capabilities, Western Jet can supply glass flight deck upgrades, NextGen, FANS, and ADS-B, inflight connectivity, and inflight entertainment (IFE).

Clay Lacy Aviation

Clay Lacy Aviation. Unscheduled maintenance is addressed through an aircraft on ground (AOG) service that operates after hours and on weekends.

A major west coast name in the world of avionics is Clay Lacy Aviation VNY. Clay Lacy is an authorized dealer for leading avionics manufacturers and connectivity providers, including Gogo, SmartSky, Satcom Direct, and Collins Aerospace.

The fact that Clay Lacy is also in the FBO, aircraft management, and charter business, provides an added advantage to owners undergoing maintenance – they can negotiate time on comparable aircraft during maintenance downtime.

Serving smaller aircraft

One challenge for owners of more specialized aircraft is finding an MRO that gives them the same attention that would be applied to better-known aircraft types. For instance, nearly everyone caters to Bombardier, Dassault, and Gulfstream, but smaller aircraft with lower production numbers have fewer opportunities.

Líder Aviacao

MROs that service the less common aircraft can achieve a level of specificity and maintenance efficiency that equates to reduced downtime and costs. Cutter Aviation and Honda Aircraft Company are representative of that relationship.

Cutter is an FAA-certified repair station, and also a HondaJet service center, authorized to conduct inspections including 100-hr, annual, and hot section, and to refurbish interiors and retrofit avionics. The international counterpart specializing in the HondaJet is Líder Aviação in Brazil.

Stevens Aerospace. It’s becoming increasingly difficult to find MROs that specialize in propeller aircraft – especially a unique type like the Piaggio P.180 Avanti – but Stevens Aerospace, with bases at DAY (Dayton OH), GYH (Donaldson, Greenville SC), and MQY (Smyrna TN), fits that bill.

Stevens Aerospace

Mather Aviation. Finding a quality MRO that performs maintenance in the jet, turboprop, and piston reciprocating market is even more rare, but one exists – Mather Aviation, with locations in MHR (Mather, Sacramento CA), MOD (Modesto CA), and VNY. Mather’s piston services include inspections, engine overhauls, paint and interior work, avionics installation and repair, and computerized maintenance tracking.


It has been said that the only constant in aviation is change. While it’s true that aircraft maintenance has evolved to the point where many of the diagnostics can be accomplished via computer, there’s still no substitute for the wrench-wielding codger with decades of experience, an astute eye, and a penchant for problem-solving.

Whether it’s a mechanic or a technician, the best relationships and most positive experiences are built on trust. Those who own and fly the aircraft trust those working on it, and vice versa. A well-established MRO with a solid reputation and dedication to customer service is the first step in solving any mechanical issue.

Shannon Forrest is a current line pilot, CRM facilitator, and aviation safety consultant. He has more than 10,000 hrs TT and holds a degree in behavioral psychology.