Approval testing continues for HF120 turbofan

 - January 28, 2010, 12:09 PM
GE Honda Aero Engines is putting the HF120 turbofan through its paces during the engine’s year-long certification tests, Bill Dwyer, president of GE Honda Aero Engines, told AIN during a recent visit to the company’s Cincinnati facility. Type certification is expected in the first quarter of next year.

Formal certification testing of the HF120 started in late July last year after an extensive demonstrator program and finalization of the design. The HF120 has a wide-chord, compound-swept front fan and two-stage booster, along with composite outlet guide vanes. The engine employs a high-temperature titanium impellor in the compressor for maximum engine pressure ratio and stall-free performance, two-stage low-pressure (LP) turbine and a counter-rotating high-pressure and LP spool shaft system, and a compact reverse-flow combustor with single-stage air-blast fuel nozzles.

GE Honda Aero Engines is targeting the 1,000- to 3,500-pound-thrust business and general aviation engine market. The GE Honda HF120 was launched in 2006 and selected to power Honda Aircraft’s light jet, the HondaJet, and the Spectrum Aeronautical Freedom.

“In 2004, when the 50-50 joint venture was formed between Honda Motors and General Electric, the purpose was to become an engine supplier to the business and general aviation industry overall,” said Dwyer.

“GE Honda Aero Engines is a marriage of two unique cultures, with Honda’s strength lying in research and development. It had been working on the HF118, the predecessor of our HF120, for about 20 years, so it had deep roots in aircraft engine R&D. GE’s contribution was a wealth of experience with the development, design and certification of aircraft engines. We have more than a billion flight hours of experience,” he said.

Dwyer cited the development of the HF120 fan as a classic example of the synergy between the two cultures. “We held a design contest between the two companies on the fan. The final design ended up being a combination of both concepts, making it overall a better product,” he said.

Rated at 2,095 pounds of thrust, the HF120 succeeds Honda’s original HF118 prototype engine, which has accumulated more than 4,000 hours of testing on
the ground and in flight. GE and Honda redesigned the engine for higher thrust and new standards of performance in fuel efficiency, durability, low noise and emissions.

Dwyer said a key cost-of-ownership advantage of the HF120 will be its ability to operate 5,000 hours between major overhauls. “That best-in-class time between major overhauls is the result of working with advanced airfoil materials and coatings for the engine’s high-pressure turbine section.”

To date, GE Honda Aero Engines has built and tested eight HF120 cores and 11 full demonstrators. During this phase of testing the engine exceeded its design goal of 2,095 pounds of thrust while improving on its fuel efficiency target and proving its durability, according to Dwyer.

“The certification test program will last approximately a year. The first engine to test was run in an altitude test cell at our Evendale facility and the performance was great. It went together smoothly in assembly, though instrumentation of an engine this small was a challenge since our team has more experience applying the wires to larger engines, but it worked out well.”

During the certification testing phase the engine is put through its paces in test cells at the company’s facility in Peebles, Ohio, and Honda’s facility in Tokyo. The company will be addressing such issues as hail, icing, bird and water ingestion, crosswind effect on air intake and the fan blade-out test, which results in the total destruction of the engine to test for blade containment.

A test engine will also be attached to the company’s Cessna CJ1 flying test bed to demonstrate it complies with the noise rules of FAR Part 33.

Upon successful completion of this phase, FAA type certification is expected and the engine will initially go into production at GE’s Lynn, Mass., facility, with the HondaJet and the Spectrum Freedom as initial applications. By the time it enters service, the HF120 will have accumulated more than 15,000 cycles of ground and flight testing.

Once the engine is certified, production will be transferred to Honda Aero in Burlington, N.C. GE Honda Aero Engines will then be responsible for all phases
of product support and future new engine development.

Dwyer said the company continues to talk with other airframers about the engine and is committed to the market segment. The engine is scalable and the joint venture envisions up to 3,500 pounds of thrust, so the company plans eventually to produce a series of engines.