Lear 45XR: The Swiss Army Knife of Jets

Refining and redefining the super-light jet category.

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Learjet 45XR

Paul Bowen

“And then we’ll drop down to, oh … 15,000 or so and do some stalls if you’re up for it,” Learjet demo pilot Chris Barnett said casually during our preflight briefing. As a jet pilot for many years, I’ve tried to keep the words jet and stalls in separate corners of the universe. “Are we really going to stall this airplane — intentionally?” I asked myself.

Yes, we were. And yes, we did.

One of the “big takeaways” after flying the Lear 45XR is the wing. It’s a nicely balanced combination of fuel efficiency, runway performance and high- and low-speed handling qualities. At 15,000 feet, with a large block altitude assigned by ATC in which to play, I pulled the thrust levers back to idle and let the aircraft decelerate through the visual and aural low-speed warnings and, finally, stick shaker. I continued to hold the control yoke in my lap until is was full back — and the airplane just began to sink at 3,000 to 4,000 fpm, with no aggressive tendency to pitch down or roll off on a wingtip; that’s a very benign stall for a jet.

Lear is proud to tout the fact that its test pilots did more than 3,000 stalls during certification flights to dial in the qualities that I witnessed. I’d say their efforts paid off; this is a very comfortable jet aircraft at slow speeds that can also fly fast and efficiently when asked.

I hope you’ll never even get close to stalling the Lear 45XR when you’re transporting corporate passengers to their Very Important Meetings, but that demo quickly created a high level of comfort for me after only a short time in the aircraft. That kind of comfort makes it a lot more likely pilots will use the aircraft for those shorter runways that we’re often asked to accommodate.

The Lear 45 was first certified in 1998 under FAR Part 25, transport category rules. When compared with FAR Part 23 aircraft, this translates into more robust system redundancy; it also guarantees performance numbers in the aircraft’s POH. The identical but 24.5-inch-shorter sibling, the Lear 40, was first delivered in 2003.

More than 525 of the two models have been delivered, which means all the inevitable “new airplane bugs” should be worked out by now.

The XR version of the Lear 45 was first delivered in 2004 and includes up-rated TFE731-20-BR engines flat-rated at 3,500 pounds of thrust at 104 degrees F, up from the original Lear 45’s rating of 86 degrees F. This power increase reduced balanced field length, especially under high and hot conditions and, of course, improved the aircraft’s climb performance. The XR upgrade also upped the gross weight by a thousand pounds, greatly increasing the type’s utility.

Variations of the TFE731 engines have powered various jets for decades and have proved to be reliable and efficient. The 45XR’s engines are equipped with a DEEC, or digital electronic engine control, which governs N1 speed and limits fuel during acceleration and deceleration, making power management a simple task. There is an engine synchronizer that keeps the big fans synced and passengers happy; it’s a good thing, since engine noise is not easy to detect from the cockpit.

Outside
During the walk-around inspection, you’ll notice large, fixed surfaces, called delta fins, extending prominently below the tail of the aircraft. They greatly increase the pitch-down moment at high angles of attack and add to the yaw stability of the aircraft; because of these fins, there is only a single yaw damper installed, and it is not required for dispatch as on many other jets.

The Lear 45XR’s wing is a beautiful, 13-degree-swept, supercritical airfoil that looks like it was carved from a single bar of Ivory soap; in fact, the upper and lower skins are machined from a solid piece of aluminum. It has no fences or leading edge slats, yet it does have vortilons along the leading edge to prevent spanwise flow, and interesting little metal triangles along the leading edge to prevent flow separation at high angles of attack. The entire polished leading edge is heated by bleed air (as are the horizontal-tail leading edges). Gracefully swept winglets add to the wing’s slow speed abilities and boost its efficiency at high altitude by about 20 percent. This is not your father’s Learjet wing.

A single point pressure refueling system (SPPR), located under the right engine pylon, is a welcome addition to an airplane in this category; the entire 904-gallon fuel system can be filled in about 10 minutes, expediting quick turnarounds. The fueling panel and associated valves are powered by the emergency battery bus, thus obviating the need for the aircraft system to be powered when filling the tanks. That’s a nice feature.

Something else that will be welcomed by any corporate pilot or ground crewman who has juggled a too-full potty or collection bag down the aisle of a corporate jet is an external access door to service the potty. Oh, the simple things!

Another great addition to this aircraft is the Honeywell APU, located above the baggage compartment. When operating in the boonies, where conditioned air and electrical power carts are often scarce, an APU makes you more self-sufficient. It is approved for use only on the ground, burns just 150 pounds of fuel per hour, provides electrical and pneumatic power, and can easily precool or preheat the 410-cubic-foot cabin before passenger arrival. That’s a big deal for corporate pilots dedicated to passenger comfort.

Let’s Fly
The Lear cockpit is tight, requiring a bit of dexterity to step over the center console, around the floor-mounted control column and into the seat – without banging your head. The rudder pedals are electrically adjustable, and the pilot seat is adjustable both vertically and horizontally. Many Lear pilots, including Chris, sit a little below the optimum eye height to give themselves more headroom. You sit quite close to the sharply swept windshield, which provides excellent visibility, but I bumped my head several times on the left side of the headliner as I adapted to the limitations of my new cockpit space.

Engine starts are simple. Just press and release the guarded start button for each engine and monitor as the DEEC schedules the proper amount of fuel; if the start goes badly, the thrust lever is lifted and pulled aft.

This aircraft has digital nosewheel steering, which, admittedly, takes some getting used to; the variable-rate system allows 60 degrees of steering authority at slow speeds and is limited to just seven degrees of travel at more than 70 knots, which prevents overcontrolling. When moving slowly, full-scale application of rudder coupled with pressure on a sensor in the pedal allows the pilot to make very tight turns in confined ramps. At first, the system seems too sensitive, but with attention and finesse you can soon master it. Maybe even love it.

The landing gear is a beefy, dual-wheeled, trailing-link arrangement, designed for an airplane weighing 36,000 pounds. It utilizes BBW (brake-by-wire) carbon brakes, and, as in any BBW system, the brakes don’t feel like “real” (hydraulic) brakes because the feedback to your feet is through springs instead of hydraulic pressure. This takes some getting used to, and exerting maximum effort for braking, it feels rather indefinite. But the carbon brakes are powerful and contribute to the aircraft’s impressive stopping and balanced field-length numbers. Chris claims the jet will stop in 800 feet at light weights, but on my two maximum-performance landing attempts, I didn’t get anywhere near that mark — I didn’t want to abuse Lear’s nice, shiny demonstrator. I did, however, turn off Wichita’s Mid Continent Runway 19R at the same intersection I had used in my Cessna 185 when landing just hours before.

The aircraft I flew was equipped with a small galley behind the pilot seats, a double-club seating arrangement with eight leather passenger seats and a fully enclosed potty, which can be used as an additional legal seat if needed. Opposite the potty is a handy, 15-cubic-foot, in-flight-accessible baggage area.

Though its demonstrator didn’t have it, Learjet will soon offer SwiftBroadband Internet access, color cabin management system touch screens, an iPod docking station, newly redesigned crew seats, wireless electronic EFBs with optional GPS and XM Weather, and better Rosen visors in the cockpit. All interior appointments on this aircraft were elegant, with fit and finish appropriate to an aircraft costing more than $12 million. Learjet does all of its own interior completions in Wichita.

The Lear 45XR is equipped with a four-screen Honeywell Primus 1000 avionics suite, with TCAS and EGPWS. The system is very intuitive and well-organized. All autopilot functions are controlled through the glareshield control panel. A centrally located EICAS (Engine Instrumentation and Crew Alerting System) calls the crew’s attention to system operations and abnormal alerts. WAAS capability and electronic flight bags are available as options, though this aircraft didn’t have them installed. No paperless chart option is available yet.

One of the unique features of the Honeywell Primus system is called “third cockpit.” In the unlikely event that both generators fail and the ship’s battery is depleted, small, centrally located screens, called RMUs, or radio management units, display engine and system information and allow you to select VHF radios and even shoot an ILS.

With two pilots and two passengers aboard and full fuel, our takeoff gross weight on Wichita’s 10,301-foot Runway 19R was 20,450 pounds, about a thousand pounds below maximum takeoff weight; balanced field length was 5,530 feet. We could have taken five more 175-pounders and flown to Port-au-Prince, Haiti, with 1½ hours of reserve fuel — or flown anywhere in the continental United States with generous reserves.

One area in which the aircraft really shines is the ability to lift loads from a high-altitude airport and transport them a long way. For example, on a 72-degree day in 7,820-foot-elevation Aspen, Colorado, the 45XR can fly eight passengers anywhere in the continental United States. It could fly those same eight passengers to the West Coast at temperatures up to 90 degrees.

We used flaps eight for takeoff, and speeds were V1, 115; Vr, 118; V2, 128. After lining up on the centerline, the thrust levers are pushed three clicks to the takeoff thrust setting, and the single DEEC (digital electronic engine control) takes care of refining the power setting for the day’s temperature and pressure altitude. All you do is monitor the engines for exceedences, and drive. Acceleration was brisk even at our weight. Nosewheel steering on takeoff takes some finesse to make it smooth for the passengers, but V1 and rotation come quickly. Rotation forces are surprisingly high for a small jet, but this makes proper pitch attitude easy to establish for initial climb; the aircraft just stays put. Roll rates are a little heavier than on earlier Lears, though the initial breakout forces in roll are quite light.

I hand-flew the jet during the climb with numerous excursions to get the feel of the aircraft. ATC was smiling on us and allowed an unrestricted climb to FL 430. In spite of my maneuvering and not caring if I climbed consistently on schedule, we reached FL 430 in 19 minutes; we could have reached this altitude without leveling off even at max weight. Once there, with ISA -4 degrees outside, the aircraft accelerated to Mach .80 and fuel flow was around 1,100 pounds per hour. I performed steep turns and purposely loaded the wing a bit to feel the low rumble of airflow separation, noting that the low-speed airspeed “foot” on the primary flight display was never very close to our indicated airspeed; this indicates a comfortable margin above stall. Again, this added to my warm, fuzzy, comfortable feeling flying the Lear 45.

To demonstrate the impressive pressurization system, Chris set one engine at MCT and pulled the other engine back to idle at Flight Level 430; the cabin didn’t even flinch. He then turned off the bleed air to the engine he had pulled back. Again, the cabin pressurization didn’t seem to care. So he turned all engine and wing bleed air on, further taxing the bleed air system, and the cabin was still stable. That’s impressive, and it’s partly a result of the airplane having passed stringent certification requirements for operation at Flight Level 510. Though you probably won’t regularly spend much time at FL 510, the capability is there when you are light (below 16,500 pounds or so). Realistically, the stringent requirements for FL 510 certification translate into a more robust pressurization system, with stronger cabin doors and a better emergency oxygen system.

In the real world, you will probably fly this aircraft routinely in the middle 40s, and it’s very capable of climbing straight to FL 430 or FL 450 at max weight. Once there, the aircraft will turn in a solid Mach .78 to .80 on about a thousand pounds of fuel per hour, depending on temperature. Climbing to FL 470, our fuel flow dropped to 1,047 pounds per hour total, or approximately 156 gallons per hour.

First landing was at about 18,300 pounds, and the aircraft made me look good with the forgiving trailing-link landing gear. Approach speeds were initially 119 knots and lowered to 117 knots as we circled Wichita’s pattern, doing multiple touch-and-goes. Single-engine departure, approach and landing were nonevents due to the excess climb performance of the aircraft. Rudder pressure with the engine pulled back was light, and I trimmed very little to compensate for the missing thrust. What an enjoyable airplane to fly.

The Lear 45XR is an impressive combination of range, economy, load-carrying capability, comfort and price. It’s a solid, mature design that offers a lot of bang for the buck in the “super-light” segment of the market shared with the Citation XLS. From a pilot’s perspective, it’s simple and comfortable to fly and a very capable jet that makes the pilot look good because of all the missions it will accomplish with aplomb. It’s easy to see why pilots, companies and individual owners love this Swiss Army knife of jets.

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