Honeywell AS907 Nears Certification

Honeywell expects its AS907 turbofan, which powers the Bombardier Continental business jet, to win FAA certification next month, and officials say they're confident the new powerplant will enjoy a trouble-free introduction based on an extensive test program.

"We now have all the certification tests behind us," said Steve Loranger, president and CEO of Honeywell's engines, systems and services business, "and we're really excited about that. It really is a big deal."

Honeywell has completed a final 150-hour certification test and is now tearing down the engine for inspection.

Loranger was also enthusiastic about the performance of the powerplant during bird ingestion tests. "It was simply outstanding," he said.

The bird tests, conducted in December and March, respectively, involved shooting a four-pound bird into the engine at a speed of 220 knots, and shooting two one and one-half pound birds into the engine at 170 knots to simulate an airborne encounter with a flock of smaller birds.

FAA certification standards require the engine to be able to shut down safely after the four-pound bird strike, but the small-bird encounter is more challenging.

In addition to continuing to produce at least 75% thrust, the engine must respond to throttle transients after the small-bird strike, simulating an aircraft go-around after ingesting birds.

The engine continued to produce 75% thrust, Loranger said, adding that officials feel "extremely good" about the engine's durability.

Honeywell has logged about 17,000 hours on 18 AS907 engines in test rigs and on Honeywell's Boeing 720 testbed, and some 1,300 hours on four Bombardier Continentals currently in flight test.

The AS907 is the first of a family of engines, Loranger said. "We are looking at the next-generation engine, which we call the 903/4/5," which will be in the 4,000- to 6,000-pounds-thrust range.

A core demonstrator is running and Honeywell is marketing the smaller powerplant to all of the business and general aviation aircraft manufacturers.