In The Works: Bombardier Learjet 70/75

 - September 5, 2012, 2:35 AM

Three jets are now flying in the Learjet 70/75 flight-test program. The first two are a Learjet 40XR and 45XR modified with the Bombardier Vision cockpit, which was installed at Garmin’s New Century AirCenter facility near company headquarters in Olathe, Kan. The Vision flight deck in the Learjet 70 and 75 is based on a Garmin G5000 avionics suite, which features touchscreen controllers mounted in the cockpit pedestal, synthetic vision display on the PFDs and Garmin’s new solid-state GWX 70 radar. The first two flight-test jets have logged more than 230 flight hours and 600 test hours, and three more jets will be used in the certification program. The third jet is undergoing interior fit and finish. The fourth has the new winglets (canted out farther than the 40/45 winglets) and new engines, and it first flew in July. Production is under way on the fifth jet, which will pull together all the new elements.

The Learjet 70 ($11.1 million) and 75 ($13.5 million) replace the 40XR and 45XR, respectively, upgrading the engines to 3,850-pound-thrust Honeywell TFE731-40BRs from the 3,500-pound -20BR (3,650 with automatic power reserve). The new engines deliver 10 percent more takeoff thrust, thanks to an yttria-stabilized zirconia oxide ceramic coating on the high-pressure turbine shrouds and on the duct between the high- and low-pressure turbine, plus improvements to the high-pressure turbine and first-stage low-pressure turbine. The new engine offers a 6,000-hour TBO and 3,000-hour hot-section interval, the same as the TFE731-20BR.

Performance improvements include takeoff field length of less than 4,500 feet, almost 200 feet shorter than that of the 40XR. The new canted-winglet design will improve aerodynamics, and the new models will offer up to a 9-percent improvement in field performance and a 4-percent improvement in fuelefficiency. Entry into service is expected in the first half of next year.