GE Honda Aero Engines has announced that its 2,095-pound-thrust HF120 turbofan intended initially for the HondaJet is nearing completion of certification tests and is on track for delivery of the first entry into service engines before the end of 2013. “We now have a line-of-sight for certification and we are gaining experience on the fleet,” said Terry Sharp, GE Honda Aero president. “We are gearing up for the production environment, which should come by the end of the year.”

Certification has been delayed by about four months following a problem encountered around a quarter of the way into the strenuous 150-hour block endurance test. Sharp described the failure as occurring in a bolt clamp in the gearbox system and stressed that there were no turbine machinery issues. Following a minor redesign and some changes to the assembly process the HF120 engine began the block test again, which was successfully completed in April. The block test is brutal: it includes 45 hours at maximum continuous exhaust gas temperature (EGT) at red-line fan and core speeds; 19 hours at maximum takeoff EGT and red-line speeds; and hundreds of burst/chop cycles. In July the block test engine will be disassembled for a complete inspection.

Currently, GE Honda (Booth 647) has submitted 180 of the 189 documents required for certification, and 158 have been approved. The final certification test is medium-bird ingestion, which will be undertaken in July at GE’s Peebles, Ohio facility. One-kilogram birds will be fired at the engine at both the inboard section (“core shot”) and outer end of the fan (“tip shot”). Final documents will be submitted in the third quarter this year, with approval expected in the fourth quarter. EASA certification has also been applied for, which would typically follow around six months after FAA approval.

Altogether, the 13 HF120 test engines have accumulated more than 7,300 hours, including 232 hours of in-flight testing in a Cessna CitationJet testbed. The engines have notched up more than 9,700 cycles, including 3,000 cycles by one engine alone as part of the endurance validation program. GE Honda plans to run this engine as a fleet-leader to the design TBO of 5,000 hours before the HF120 is ready for deliveries to begin.

In anticipation of certification GE Honda is stockpiling components and conducting supplier readiness reviews. Initial production engines will be assembled at GE’s Lynn, Massachusetts plant, but early next year production will transfer incrementally to GE Honda Aero’s Burlington, North Carolina facility. This process is expected to take around a year to complete.