At just six years of age, GE Aviation’s GEnx engine aftermarket is still in the early stages of what will be a long and lucrative ramp-up. While a steady stream of scheduled off-wing overhauls is a few years off, the engine’s global support network has been busy preparing for the work while tackling typical entry-into-service issues.

“The GEnx MRO network has seen a variety of shop visit work scopes,” says Kathy MacKenzie, general manager of the GEnx program at GE Aviation. Chief among them: a set of light repairs to address “durability-related items” and more comprehensive visits to incorporate packages of upgrades, or Performance Improvement Programs (PIP). 

“The PIP workscopes are extensive upgrades similar [to], actually slightly heavier than, a typical performance-restoration shop visit,” MacKenzie explains.

Both GEnx versions—the -1Bs that are an option on the Boeing 787 and the -2Bs that power all Boeing 747-8s—have two PIP packages, developed to incorporate performance-enhancing upgrades. GE also has recommended several other changes, including fan-case modifications—later mandated by the FAA—on PIP-2-standard -1Bs to address an ice-ingestion issue. The repair was part of a series of changes resulting from a January 2016 inflight shutdown caused by ice ingestion. 

The GEnx family entered service in late 2011, when freight carrier Cargolux introduced the 747-8. The -1B followed about six months later, when Japan Airlines put the first GE-powered 787 into revenue service. As of Oct. 31, there were 135 747-8s in service or on order—equivalent to 540 -2Bs, not counting spares—while GE had sold more than 1,600 -1Bs to 51 787 customers. 

Entry-into-service (EIS) teething problems, while commonplace, are disruptive for operators. If there is a silver lining, it is that the OEM gets a firsthand look at more in-service wear issues than it would expect. Much as early operational data can point to needed PIP improvements, a peek at young engines pulled into shops usually drives MRO changes that benefit operators as their equipment ages.

“The GEnx program uses the shop visits as part of our leading-indicator program,” which is GE’s focus on pinpointing both positive and negative conditions early in an engine’s service life, MacKenzie says. “These programs involve endurance testing, on-wing monitoring and shop visit finding reviews, to name a few key attributes.”

The early shop visits also provide a test for the support network. 

“Shop visit learnings to date helped GE identify where we needed to expand the GEnx MRO network and material-planning needs,” MacKenzie says.

The GEnx network includes some familiar names, led by GE Aviation overhaul facilities in Prestwick, Scotland, and Petropolis, Brazil, and its Evergreen Aviation Technologies Corp. joint venture with EVA Air. Network partners include Air France-KLM (AFI-KLM), Air India, Lufthansa Technik (LHT) and Turbine Services & Solutions (TS&S) Aerospace. The GE-owned and joint-venture shops as well as TS&S are set up for all GEnxs, while the other partners specialize in either the 747 engine (LHT) or the 787 powerplant (AFI-KLM, Air India). Other MRO partners include MTU, which repairs turbine center frames—or ducts between the high-pressure and the low-pressure turbines—that MTU also supplies.

Both GE’s shops and the partners have been handling early shop visits while preparing for steady scheduled work. For example, AFI-KLM earlier this year opened a test cell in Paris to support the operation’s Amsterdam engine shop, which already has about 10 customers. The shop finished its first -1B quick-turn visit in December 2015, becoming the first non-GE shop to do the work. TS&S, meanwhile, has touched more than 20 GEnx engines for a handful of customers.

Aviation Week’s Commercial Fleet & MRO Forecast projects the total GEnx MRO market at $14.8 billion through 2027. Most of it—$10.6 billion or 72%—will be generated by the -1B. The work will stem from nearly 3,800 events, both performance restorations and full overhauls. The -1B will account for about 2,800 of them, the forecast projects.

“The engine is still early in its life cycle, and we expect significant shop volume over the next 10 years as engines mature and performance restorations begin,” MacKenzie says.

Another sign of a maturing program: availability of used serviceable material (USM). The GEnx market is too green for USM, but that will change. 

“Given our current point in the GEnx life cycle, six years since EIS, there is not a significant amount of USM in the market” MacKenzie says. “GE anticipates the GEnx USM market will evolve in the future to be similar to other widebody engine programs.”