Honeywell is targeting the third quarter of next year for the certification of the HTF7500E turbofan. This is a revised schedule that fits with Embraer’s delay in developing the midlight Legacy 450 and midsize Legacy 500 business jets.
“We have begun the formal Part 33 certification program,” Jim Kroeger, Honeywell’s director of engineering for propulsion engines, told AIN. The development program is “essentially complete,” he said. Six engines are involved in the certification program, and five have flown on the engine maker’s flying testbed, a modified Boeing 757, to demonstrate operability and performance.
“We want Embraer’s certification program to be as short as possible, as far as the engine is concerned,” Kroeger said. The HTF7500E will be rated at 6,080 pounds (takeoff thrust, ISA+15-deg C) on the Legacy 450 and 6,540 pounds on the Legacy 500. First in the airframer’s pipeline is the Legacy 500, which is expected to fly by year-end.
As of late last month, Honeywell had delivered engines for the first two aircraft and was about to hand over a third pair. Spare parts have already been provisioned to support the aircraft’s development program. Shipment of production engines will begin after certification of the HTF7500E.
Among the development tests Honeywell has run, noteworthy are two endurance trials. Two engines have been subjected to 2,000 hours each of equivalent run time, simulating actual service operations. “I am confident with the results demonstrated,” Kroeger said, adding that part of his assignment is to make the HTF7500E “as reliable as the HTF7000.”
The new engine features the Saber 1 low-emission combustor (where Saber stands for single annular combustor for emissions reduction). It is based on a rich-quench-lean scheme. The combustion commences with a rich setting and is quickly leaned out to mitigate the formation of nitrous oxides (NOx). The technology enables a 25-percent reduction in NOx emissions and does not compromise the durability of the combustion system, according to Honeywell.
For Embraer, the engine company is supplying an integrated powerplant system, where the engine comes with its nacelle (built by GKN Aerospace) and other equipment. This includes, for example, the inlet, the thrust reversers (built by Safran) and the engine build unit–bleed ducts, hydraulic lines, fire detection and so forth.
In the same engine family, which entered into service on the Bombardier Challenger 300, Honeywell (Booth No. 4494) also developed the HTF7250G for the recently certified Gulfstream G280 super-midsize business jet.