The Model 45 is Learjet's first all-new aircraft since Bill Lear's first Model 23. Although it looks like a Learjet, it has only half the parts of a Model 35, reflecting a significant design progression. The parameters set down for the 45 called for it to have the performance of the Learjet 35, the handling of the Learjet 31A, and greater cabin space than the competition.
This is Learjet's first paperless airplane, designed entirely on a computer screen. In some cases, the computer design files are loaded directly into production milling machines, which allows for an exceptional degree of precision in manufacturing (especially important when major parts that have to fit together are made on different continents!). This reduces not only time in construction but also the rate of rejection of parts (inherent in any manufacturing process).
Like so many ventures today, building Learjets is a cooperative arrangement of various entities. Learjet is responsible for systems and final assembly in the United States; the fuselage is built by Shorts in Ireland; and the wing design and construction is handled by de Havilland in Canada (all Bombardier subsidiaries).
Ease of operation was a key design goal with the new Learjet. In addition to fewer parts, the craft has a built-in maintenance tracking system. A technician can plug a laptop computer into a panel and download a fault list from all of the avionics, engines, and other systems.
The 45's glass cockpit makes for simplified in-flight system management. The Primus 1000 integrated avionics system and engine instrument/crew advisory system (EICAS) has a page for monitoring every major system as well as for displaying primary flight instruments.
Power management usually creates a high workload when flying jets, thus requiring new power settings with changes in weight and ambient conditions. The Learjet 45 takes much of the power management off the pilots' hands by computing it for them. For takeoff, for example, advance the thrust levers three clicks to the takeoff position, feet off the brakes, and you're out of here. During the climb, ease the levers back a notch to the max continuous thrust (MCT) position, and let the digital electronic engine computer (DEEC) worry about the rest.
At 45,000 feet and a weight of 17,000 pounds, the high-speed cruise number is 445 KIAS with a fuel flow of about 1,062 pounds per hour (pph). Back the power down to a long-range cruise setting, and the speed decreases to 408 knots, while fuel burn slows to 987 pounds per hour. The 45 has a maximum IFR range of about 1,800 nautical miles. With a maximum operating altitude of 51,000 feet, the 45 easily reaches and cruises at 45,000 feet, unlike some lighter jets that are certified to 45,000 feet, but are rarely used at that altitude.
Learjet has shown once again its ability to adapt to the market and produce what the customer wants. In the Model 45, they have crafted a machine that gets the customer there on time and in comfort while keeping the pilots and the corporate flight office happy.
||Mach 0.81 464 knots
|| 859 km/h|
Two Allied Signal TFE731-20 3,500 pounds thrust
||904.8 U.S. gallons
|Maximum Gross Weight
Up to 9