As airliners have grown bigger, so have the jet engines needed to thrust them into the air. We're now at the point where the words “jet engine” conjure up something with a maw big enough for a Mini Cooper to easily drive through. But not every jet aircraft is a double decker people carrier and not every engine is a behemoth. On Thursday, General electric announced that the HF120 jet engine it’s co-developing for the HondaJet completed its US FAA certification testing – and its fan aperture is only 18 inches (45.7 cm) across.

The HF120 may be small but, according to GE, it can still put out 2,095 lb of thrust. A variant of the Honda HF118, it’s the first turbofan produced by the joint venture GE Honda Aero Engines. It uses a wide-chord swept fan feeding a two-stage, low-pressure compressor and a counter-rotating, high-pressure compressor with a titanium impeller. Honda had been developing similar engines since 1986 and the final version was produced in collaboration with GE. GE says that the lightweight design not only exceeds business jet environmental standards, but also enjoys improvements in fuel efficiency.

Terry Sharp, president GE Honda Aero Engines, describes the GE/Honda collaboration on the HF120 as one of Honda setting it up, so GE could bring it home. "They had an engine that was running, but GE knew how to put engines into service. Together we've redesigned the engine and put it through the FAA tests, which require conditions far and above anything that you see in service."

With its distinct over-the-wing twin-engine mount, the HF120 is an integral part of Honda’s first business jet, HondaJet; the first six production versions of which are currently under construction by Honda Aircraft. Under development for the last decade, it’s designed to carry up to six passengers and has a 12.15-m (39.8-ft) wingspan and overall length of 12.7 m (41.6 ft). It also boasts a cruising speed of 778 km/h (483 mph, 420 knots) and a range of 2,593 km (1,611 mi, 1,400 nmi).

Its airframe design is claimed to reduce cabin noise and ground-detected noise as well as providing more cabin space and greater cargo capacity. In the cockpit, there is a Honda-customized Garmin G3000 next-generation all-glass avionics system with three 14-inch landscape-format displays and dual touch-screen controllers.

GE anticipates receiving final FAA approval for the HF120 this year and will begin full production in 2014. After numerous delays, some related to the engine, the HondaJet is also expected to receive FAA certification in 2014.

Source: GE