Where the GE38 leads, others will follow

GE taps new market with GE38-1B

By Stephen Trimble / Washington DC

Two extremes divide the current market for large turboshaft engines. Europrop International occupies the high-end with the 10,000shp-class TP400. Rolls-Royce dominates the low-end with the 6,000shp-class Rolls Royce AE2100/1107C family.

Between these extremes lies a currently vacant, vast middle ground ripe for development and growth over the next few decades.

First to market in this unpopulated market region will unquestionably be the General Electric 7,500shp GE38-1B, selected 18 months ago to power the 84,700lb US Marine Corps Sikorsky CH-53K.

GE has finally disclosed the first details about the GE38's closely-held development programme, as well as offered a glimpse of the company's vision for the heavylift market space.

Ed Birtwell, GE's vice president and general manager for turboshaft engines, compared the new GE38's market potential to that of the company's flagship T700, a 3,000shp-class engine that powers thousands of Sikorsky Black Hawk and Boeing AH-64 Apache helicopters, among many others.

"We hope that this is a programme that has the success of the T700 with other applications," Birtwell said.

To realize that potential, new classes of heavylift helicopters and medium-lift, fixed-wing transports will have to emerge over the next decade. The market could include growth versions of existing helicopters like the CH-53K, as well as possibly all-new aircraft.

"We will always have a huge need for medium lift helicopters like the Black Hawk," said Rhett Flater, executive director of the American Helicopter Society. "On the other hand, some of the experiences that the US Marine Corps and the army have encountered in Afghanistan in particular, but also Iraq, justify the need for helicopters capable of carrying heavier payloads."

Another option for GE could be capturing a share of Rolls-Royce's grip on the heavy-lift market.

The USMC is investigating the GE38-1B as a replacement for the AE1107C that powers the BellBoeing MV-22 Osprey, a medium-lift tiltrotor. USMC officials have expressed concerns about the durability of the AE1107C after experiencing sand ingestion in Iraq.

"The AE1107C compressor does not currently take advantage of protective coatings to minimize sand and dust erosion," Rolls said in a statement.  "However, we have outlined with the customer an engine coating program to begin in-service evaluations in the near future."

Lockheed Martin also may have to upgrade the payload capacity of the venerable C-130J Hercules, as the size of the vehicles for the army's Future Combat System grows from about 20t to about 27t. At that time, the GE38 may be viewed as an attractive alternative to the Rolls AE2100.

Birtwell declined to comment about specific opportunities for the GE38 beyond the CH-53K, but clearly described GE's strong interest in pursuing those options.

"GE made an investment in this program as well. It's not just government money," Birtwell said. "We did it for a reason. We are highly aware of the various other applications in this power class."

GE's competitors are also well aware of this potential new market. Honeywell builds the 5,000shp T55-GA-714 engine for newer-model Boeing CH-47s, and has advertised a more powerful, next-generation version called the 55-L-71X.

Facing such competitive pressure, GE is holding off on concepts for future applications to focus on delivering the GE38-1B on time for Sikorsky's CH-53K programme.

"We do need to focus on this one particular job because we want to get the engine right first and then we can work on other things," Birtwell said.

Earlier this month, GE released engineering drawings for engine parts to the supply chain, he said. Passing that internal milestone means the company has finalized design of the engine components, allowing fabrication of parts to begin for the first engine to test.

The first rig test is scheduled in July to analyze the combustor. That will be followed by a second rig test in the first quarter of 2009 to check the lubrication system at various engine attitudes in pitch and yaw.

The first complete engine to test is scheduled to be installed on GE's test stand in the first half of next year. GE is building a total of 20 engines to support 6,000 hours of flight testing on five prototype CH-53Ks.

The GE38-1B emerged as an outgrowth of the GE27 "mature technology demonstrator engine" in the 1980s and the T407 proposed for the subsequently cancelled Lockheed P-7 patrol aircraft. The GE38-1B is based on the same architecture, but boasts 20% more power than the T407 driven by an updated core hot section and a redesigned power turbine.

For the CH-53K, GE was initially prepared to offer a growth version of the GE T64 engine that currently powers the CH-53E fleet.

However, "as the requirement evolved the power requirement got to be such that it was more than the T64 architecture could handle," Birtwell said.