manually actuated. Bungee springs connected the rudder pedals to the nose wheel steering linkages. A two-position horizontal stabilizer was fitted to the tail to compensate for hefty changes in pitching moment caused by extension and retraction of the large wing flaps. In contrast to the Citation V Ultra’s notoriously stiff straight-leg undercarriage, the Excel would be endowed with trailing link landing gear for smooth touchdowns instead of the Ultra’s embarrassing kerplunks. Cessna’s well- proven open center/closed loop hydraulic system powered by engine-driven pumps was only pressurized on demand to actuate the landing gear, wing flaps, and speed brakes. A separate electrically powered hydraulic power pack was used for the brakes. The resulting back-to-basics amalgam of parts, including the tubby fuselage, straight wing, and cruciform tail, made the CE 560XL Citation Excel arguably the least comely jet in the midsize market. However, it offered everything for which customers had asked. Buyers just laughed at its looks and signed deposit checks in record numbers before the official launch. When the Excel was publicly announced at the 1994
The Learjet 45, though, only had an air-cycle machine for cooling and heating. And that required an engine to be running, as an optional APU wouldn’t become available until well after initial deliveries began. Unlike older Learjets, the Model 45 wasn’t equipped with a vapor-cycle air-conditioner as a weight-saving measure, so it couldn’t be plugged into a ground power unit for cooling prior to engine start. As Citation customers were willing to settle for 400- to 410-knot cruise speeds, Sills didn’t have to design a clean- sheet wing for the new jet. He could adapt the Citation V Ultra’s semi-supercritical airfoil by adding a wider chord root section with swept leading edges. This increased span by 3.6 feet and actually improved lift-to-drag characteristics compared to the Model 560. The Excel’s wing structure was mounted low on the fuselage to reduce interference drag with the fuselage and assure the spars didn’t intrude in the cabin’s 8-inch-dropped center aisle. The Excel’s systems would align with the “simple Citation” design philosophy. Similar to Learjet 45, the aircraft would use Honeywell Primus 1000 avionics, but the layout was simpler. The primary flight controls would be
“It’s the cabin, stupid,” said Excel sales executives in the 1990s, mimicking a popular presidential campaign slogan of the era. It was also price, utility, operating cost, and Cessna’s top-rated product support. But, the last generation 560XL looked dated, so Textron Aviation created Ascend, embracing lessons learned from its Latitude super-midsize jet.
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