Drive east from Cincinnati along Ohio state highway 32 towards Virginia and the roads get progressively emptier. Small towns hunker down in the frigid Midwestern winter landscape, dots of colour in a sea of rolling brown hills. The further west you get, the deeper into Amish country you are – signs warn of the likelihood of encountering slow-moving buggies ahead. But every now and then flashing orange lights strobe along the oncoming carriageway as a huge tractor-trailer rig approaches, a wide load sign displayed on its nose. In the well of each of these low-loader trailers is a tarpaulin-wrapped shape that despite the covers is unmistakably a large jet engine.
It is an utterly incongruous sight, hinting at the sort of high-tech manufacturing not generally associated with a part of the world where barn raising appears to be the biggest local industry. But off the main road, just past the town of Peebles, the reason why millions of dollars-worth of jet engines are being hauled around quickly becomes apparent.
There, tucked away among 10 square miles of forest on a site that includes its own beaver dam and herds of wild deer, is engine manufacturer GE’s test facility. It dates from the 1950s, when the company first used the site to experiment with different types of rocket fuel. A few traces of this era remain – including the former test control room, now relegated to use a paint storage shed – but by and large the site is now a picture of modernity.
Isolation is granted by the acres and acres of empty woodland – our guide for the visit points to a barely-visible electricity pylon several miles distant, to illustrate the scale of the site. It also sits within the airspace of nearby Rickenbacker air force base, deterring any overflights. The overall impression of the place is of a Bond villain’s secret lair – it even has its own runway, albeit a decommissioned one.
GE has been expanding Peebles in recent years as it plans a virtually unprecedented ramp-up in production across its portfolio. In fact, says site leader Brian DeBruin, the company has invested some $70 million in the facility over the past two years – and that excludes the earlier construction of an outdoor test rig for the now-cancelled F136 military engine for the Lockheed Martin F-35, which has been pressed into wider use. The recent spending round has included building two additional indoor test cells, accounting for $40 million of that $70 million expenditure. The last of these – test cell 5D – was handed over late in 2014, and the final stages of calibration work were taking place during our visit in late January.
Dust Ingestion testing is carried out at Peebles
CFM International
These huge cathedral-like spaces are predominantly used for pre-delivery engine runs, and the investment in additional capacity speaks volumes about planned production increases. For instance, GE’s CFM International joint venture with Snecma is expected to increase narrowbody engine production from around 1,500 current-generation CFM56Bs this year to 1,800 by 2019 – the majority of which will by then be the in-development Leap powerplant. As with the CFM56, many Leaps will be assembled by GE’s French partner in Villaroche, but that leaves a substantial number – everything destined for Boeing’s 737 line in Seattle, for a start – to be absorbed by Peebles. And that doesn’t take into account the increased production of the GEnx-1B required for the 787, continued high rates on the GE90 for the 777 and, towards the end of the decade, the arrival of the GE9X for the 777X.
Final assembly of all the large powerplants takes place at Peebles, and that part of the facility is growing too, with an additional load-out bay – where the complete engines, plus test nacelles, pylons, inlets and its test frame are transferred onto the back of a truck – currently under construction. When finished there will be a bay for each of the widebody engine models assembled at the site. Once aboard the tractor-trailer, the engines, now weighing in at double their bare weight of 7.5t apiece, are painstakingly low-gear-hauled up what GE refers to as “the hill”.
This is where the seven outdoor test stands are located. Presently they’re pretty busy. At least three spaces are occupied by GE’s new Passport business jet engine, as technicians prepare for blade-out, water ingestion, and crosswind tests – the latter carried out using a rig that can create a 50kt gale at right-angles to the engine. “We can get it so that no matter the position of the aircraft we can check that the engine behaves in all flight characteristics. It has to be outside the curve that it could ever fly in,” says DeBruin.
A pair of the new Leap engines – a -1A for the Airbus A320neo and a -1B to power the 737 Max – are also on stands as the programme accelerates towards planned certification next year. Peebles has played a key part in that process, having performed the pre-flight trials of the two engines – a -1C and -1A – currently being used in the flight-test campaign in Victorville, California.
Alongside the investment in site infrastructure, GE has also been increasing personnel, with 70 new staff members added over the last two years. This takes total numbers at the facility to around 350 direct employees, plus an additional 150 contractors. With the anticipated ramp-up in activity, the recruitment push has been vital. “We’ve spent a lot of effort on being ready and have the right capability and resources because we know that we don’t have the time to lollygag,” says DeBruin.
GE’s investment in Peebles is part of a broader expansion across the whole of its aero engines business. This has included acquisitions, such as the 2012 purchase of Cincinnati-based Morris Technologies and 2014’s capture of Avio Aero in Italy, as well as the opening of new factories to support the engine ramp up.
Of course, those two takeovers were not simply about obtaining additional capacity, but also increased GE’s manufacturing capabilities.
Much has been written about the additive layer manufacturing (ALM) processes championed and honed by Morris – and Avio to a lesser degree – but they form an important part of the jigsaw. Aside from the rapid prototyping now available, techniques developed by Morris – now rebranded as GE’s Additive Development Center – are to be used to produce components on several engines, notably low-pressure turbine blades on the GE9X and fuel nozzle tips on the Leap series.
ALM is quicker than subtractive manufacturing techniques and allows the creation of structures that could not be realised with older technology. To put it another way: if you can print the part from the ground up, you can create all kinds of clever internal structures that would be impossible to machine.
GE plans to produce the ALM nozzles at a new facility in Auburn, Alabama, which is due to open by the middle of this year. Capacity will be around 30,000 initially, rising to 100,000 by 2020. And although the materials used in ALM are not yet ready to be applied to high-pressure turbine blades, where single-crystal castings are desired, the rapid production cycle it permits has helped GE’s engineers to revise the unique internal cooling structure of the next-generation components, says Mike Cloran, the Additive Development Center’s marketing manager. These will feature on the Leap powerplants, with a more advanced iteration to feature on the GE9X.
What may not be possible now could become viable in the future as the technology matures, Cloran says. “Forging has been around for hundreds of years, machining and casting have been around forever, [ALM] has only been around for 10 years.
“It is going to look very different in the future. What we can do today is only a fraction of what we will be doing in 10 or 25 years.”
Source: FlightGlobal.com
