Turbine Pilot

Few general aviation manufacturers have experienced the highs and lows of Learjet. For about the first 30 years of its existence, the company was bought and sold by a series of entrepreneurial owners — always enthusiastic but not always capable of efficiently building and selling business jets.

Aerospace conglomerate Bombardier changed all of that in 1990 when it purchased Learjet and folded the manufacturer into its organization. Today, Bombardier, with its Learjet, Canadair, de Havilland, and Short Brothers subsidiaries, is the world's third largest aerospace company behind Boeing and Airbus. With the purchase Bombardier has brought a financial stability that Learjet has never before experienced. The result has been three new airplanes in the last seven years, more than the company has ever produced in such a short period of time. The first Learjet out the door under the Bombardier banner was the Model 31A, an update to the 31 and follow-on to the 35, and then the Model 60, a stretched and modernized version of the 55.

Still, those were all derivative designs of the first Learjet, which debuted 34 years ago. Recognizing that the original platform may have been stretched and tweaked as far as it could be, and wishing to take advantage of modern manufacturing processes and efficiencies, the Bombardier management began development of an all-new airplane to be dubbed the Learjet 45.

After years of meeting to hear the wants and needs of business jet users — some Learjet customers and some not — engineers passed the airplane's electronic design from the computer screen to the milling machine. What finally emerged was the first all-new Learjet since the Lear Jet 23. With its signature wraparound windshield, elegantly long nose, and graceful wing, you'll have no trouble recognizing the 45 as a Learjet, but the similarity to the older products is only skin deep. The new version has half the parts of a Lear 35 and takes far less time to build. In fact, the only parts in common with the other airplanes are the nosegear strut and the nosewheel — not the tire, just the wheel, reminds James P. Dwyer, Learjet's chief of flight test programs.

"Basically, we started with the cabin — really the lavatory — and built an aircraft around it," explains Bill Monroe, vice president of sales. As with many business jet projects, finalizing the 45's lavatory design took an extraordinary amount of time. In the end, the lav and its flushing potty are in the back of the airplane, stretching across the 45's wide oval-shaped cabin. Farther forward, eight passengers can sit in the standard double-club arrangement. Because the seat tracks extend the entire length of the cabin, customers may configure the seats any way they like. The oval-shaped cabin provides maximum head and shoulder room near the side walls. Other Learjets have round cabins. Because the wing carry-through structure runs beneath the floor, the 45 is also the first Learjet to have a flat cabin floor; there is no spar to step over.

The 45 differs from its stablemates in a number of other ways. For example, the 45 is the first Learjet to use a brake-by-wire system. Step on the brakes and you're shuttling some electrons to a black box deep inside the airplane. It figures out how much braking you want and then commands it from the brake system. The 45 is also the only Learjet to have a trailing-link main landing gear, a system that makes even a novice pilot's landings look good to the boss in the back. Earlier Learjets use bleed air for windshield anti-ice. The 45 uses a glass windshield with electric anti-ice.

Skin deep

The slick and smooth aluminum skins hide the new maintenance philosophy inside the 45. Throughout the development of the new model, Learjet focused much attention on maintainability. According to Wesley E. Lumry, maintenance manager on the Lear 45 project, his team was involved from the very beginning, ensuring that designers kept the end user in mind. The 45 is the first Learjet with a complete maintenance tracking system built in. A technician can plug a laptop computer into a receptacle in the panel and download a fault list from all of the avionics, engines, and other systems. "The computerized diagnostics system has become the primary maintenance tool rather than supplemental, as it was originally envisioned," explains Lumry. "The goal is to reduce the amount of repairs, the inventory of parts, and our warranty exposure, and to make the aircraft more serviceable."

This philosophy extends to the engines and avionics, too. The 45 is the first jet in its class to utilize the Primus 1000 integrated avionics system and engine instrument/crew advisory system (EICAS). The four 8 X 7-inch cathode-ray tubes provide each pilot with a primary flight display (PFD) and a multifunction display (MFD). The EICAS has its own dedicated display, although that same display can be used for any of the other functions, if desired. In fact, information from any display can be put on about any other to assure redundancy. The EICAS can even be displayed on one of the two color LCD radio management units. From the RMUs, either pilot can program any of the communication or navigation radios and the transponder. The Universal UNS-1C flight management system is standard. A second FMS is optional.

Attitude and heading sensing is derived from Honeywell's solid-state interferometric optical gyro system (IFOG). In conventional systems, gyros spun up by vacuum or air pressure sense shifts in attitude and heading. To determine changes in aircraft position, IFOG measures the phase shift produced between two beams of light traveling in opposite directions through optical fiber wrapped around a core. The result is greater accuracy and reliability in a very small, lightweight box.

The Learjet 45 comes standard with the Honeywell 650 color weather radar; the Honeywell 870 Doppler radar with turbulence detection is optional, as is either TCAS I or II. The 45 is also certifiable for Category II instrument approaches and for use in areas with reduced vertical separation minimums (RVSM), which are now in effect over the North Atlantic.

Power management is a jet pilot's biggest nemesis. For every takeoff and landing, new power settings and V speeds must be computed based upon weight and ambient conditions. The systems on the 45 eliminate most of that. Enter the weight of baggage and passengers; the FMS, already knowing the altitude, temperature, and fuel load, will compute all the V speeds and send them up to the Honeywell EFIS. There, the speeds will be shown on the airspeed tape along the side of each PFD. Forget about computing the proper N1 speed for takeoff power, too. The digital electronic engine computer (DEEC) does that for you. For takeoff, advance the thrust levers three clicks to the takeoff position, which will be noted by an annunciator on the EICAS display. Feet off the brakes, and you're out of here. During the climb, ease the levers back a notch to the MCT (max continuous thrust) position, and let DEEC worry about whether you're temperature limited on that particular day.

Like the 30-series Learjets, the 45 is powered by a pair of AlliedSignal turbofans. In this case, it's the TFE731-20 engines, each generating 3,500 pounds of thrust at takeoff — the same thrust as the Learjet 31A. However, the 45's engines are flat rated to produce that thrust at temperatures up to 88 degrees Fahrenheit. As a result, the 45 turns in climb and cruise performance on par with the 31A even though the new airplane weighs some 3,000 pounds more at its max takeoff weight.

The human element

Sophisticated and integrated systems are terrific, but it's still humans who have to manage them. Here, the 45 excels as well. All major systems have their own page on the EICAS display. Take your pick from the softkeys across the bottom of the display. Choose electrical, for example, and you'll get a simplified schematic of the electrical system. Meanwhile, switches and controls for the systems are grouped together by function and spread neatly across the bottom of the panel.

It all sounds a bit overwhelming, but, in fact, it's not. In flight, the systems play together like some big-city orchestra. As a result, the pilot can concentrate on flying the airplane.

For startup, move the thrust levers out of the fuel cutoff gate and hit the Start button. DEEC does the rest. Chief Test Pilot Dwyer programmed our weight into the FMS and it came back with a V1 and VR of 113 knots and a V2 of 126. With 4,020 pounds of fuel on board we taxied out weighing 17,961 pounds, about 2,200 pounds below the 20,200 max takeoff weight. With a steamy outside temperature of 95 degrees Fahrenheit, DEEC would limit the takeoff power to an N1 of 88.2 percent. Our accelerate/stop distance would be 5,160 feet — no problem on Wichita Mid-Continent's 10,300-foot Runway 19R.

On the runway, three clicks of the thrust levers to the Takeoff position and we were away. A low-flying airplane south of the field showed up on the TCAS right after takeoff, so we quickly began a turn to the west, headed for Learjet's flight test area. It was immediately evident that Learjet's efforts to refine the flight control system had worked. Beyond a certain aileron deflection point, spoilers seamlessly begin to aid in the turns. The use of dual independent flight control systems will be standard in all future FAR Part 25 airplanes because the regs require manufacturers to provide complete flight control redundancy in the case of a control surface jam or damage. At 17,000 feet, Dwyer disconnected the roll flight controls. In that case, the pilot can turn the airplane by using just spoilers; the copilot controls only the ailerons. By holding his yoke still, Dwyer simulated a jammed aileron. My yoke continued to actuate just the spoilers, providing complete roll control, even at very low speeds. Likewise, the elevator system has a disconnect, giving each pilot control of one side of the elevator.

With the flight control system put back together again, we headed up to FL450. Flying at 250 knots indicated and later Mach 0.72, we initially maintained a climb rate in excess of 3,000 fpm. By the time we reached about 40,000 feet, the climb had dropped to just below 2,000 fpm. At high and low speeds during steep turns, stalls, and single-engine work, the 45 proved to be entirely predictable and stable. Dwyer is correct when he states, "It flies like a Learjet, but it's the best flying Learjet you've ever flown."

In cruise, the 45 turns in its highest speeds at maximum weight at 33,000 feet where it tools along at 444 knots true on 1,715 pounds per hour. It picks up a few knots at lighter weights, which would be more typical by the time you reach altitude.

At 45,000 feet and at a weight of 17,000 pounds, for example, the high-speed cruise number is 427 knots on about 1,062 pph. Back the power down to a long-range cruise setting and the speed decreases to 408 knots, while fuel burn slows to 987 pph. The 45 has a maximum IFR range of about 1,800 nm. 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 rarely are used at that altitude.

Returning to Wichita, we did a practice ILS to Runway 19R and a couple of touch and goes. On the last "go," Dwyer pulled the right engine, but not before warning me. I added a little rudder trim, and the 45 once again showed its gentle manners as we limped around the pattern for a full-stop landing. The thrust reversers on the flight test airplanes were pinned to prevent deployment.

Certification of the airplane was scheduled to be completed by late August. Within the next few months, Learjet will complete certification of the thrust reversers, which are standard equipment. Here DEEC comes into play once again, managing engine thrust during reverser deployment. As airspeed decays, the system reduces available thrust to prevent ingestion of dirt or debris. The pilot needn't be concerned about that, though. Just haul back on the paddles to deploy the buckets and increase reverse thrust.

Going to market

When adjusted for inflation, the price of a typically equipped Learjet 45, at about $7.5 million, goes out the door at about the same price as the last Learjet 35, which was produced in 1992. Certainly the 45 fills a hole in Learjet's model line. The 31A is smaller and has less range and payload and also costs about $2 million less. The larger and longer-legged Learjet 60 (the 45's cabin is actually longer than the 60's) will set you back about $10.5 million. The yet-to-be certified Cessna Citation Excel is the 45's biggest competitor. With Excel's certification now pushed back until early 1998, Learjet has a slight edge in the competitive business jet market. Loyalty to the Cessna products runs deep, however.

Still, Vice President of Sales Monroe says that customers are giving the all-new Learjet a look. "Unlike earlier Learjets, this one is attracting a number of customers from other camps." It's true that Learjet has had a cult following over the years. Company officials believe that the 45, with its typical Learjet look and feel, can embrace those traditionalists, while at the same time attracting new customers who will appreciate Learjet's efforts to build a completely new airplane with the customer in mind.

E-mail the author at [email protected].

Talking With Bombardier's Mike Graff

Learjet's next model and the Global Express

BY THOMAS A. HORNE

In 1996, Bombardier's Business Aircraft Division had a top-level reshuffling of corporate officers. The division includes Learjet, Canadair, and Global Express. Former President John Lawson was named president of the division's sales organization. Replacing him is Michael Graff, a former partner of McKinsey and Company, an international consulting firm. Harvard- and Massachusetts Institute of Technology-educated in management studies, Graff has experience that isn't limited to boardrooms. He once toiled in a Pittsburgh steel mill before deciding that "this wasn't really all that I was looking for out of life." Pilot caught up with Graff at this year's Paris Air Show; an edited version of the conversation that took place follows:

Pilot: You've mentioned that there will be a follow-on airplane to the Lear 45, one that will fill the gap between the Lear 60 and the Challenger 604. Will that design be based on the Lear 45?

Graff: That's one option. What we're doing now is trying to understand our customers' requirements.

How would the new airplane differ from some of the other competitors in the super-mid-size market? And do you think that this market segment is becoming too crowded, what with the Hawker Horizon, the Galaxy, and the Citation X in the same niche?

Well, it would be all-metal, for one thing. And I don't think the market is all that crowded. Raytheon must leave room between its Premier II and the Horizon … we've got to have continuity in our product line, and we want to see who the likely prospects are.

You're quick to say the design will be all-metal …

Well, all-composites [designs] will be a challenge. It's no secret that composite fuselages have problems. But that doesn't mean we won't use composites where they make sense. [Composites] are a challenge on the production line in day-to-day manufacturing. Another thing will be maintainability in the field. We have sources that indicate challenges there, too …. Raytheon is a great competitor … but move the price up 20 percent and price point becomes a real issue.

How is Lear 31A production going? What's that airplane's longevity?

We have options through the year 2000. The 31A continues to perform well. This year we plan to sell a dozen, and they've done well in the first half [of 1997]. It's really cheap to operate — and very popular on two- to two-and-a-half-hour missions. But, we're looking closely at our options. We couldn't have a new airplane within three years, so the 31A will continue for three years, at least.

What about the Global Express? How's it coming along, and have you lost any customers to the G-V?

We've lost some prospects to the G-V. We just lost one because [Gulfstream] offered him a deal. But, there have been cancellations of G-V orders by people who switched to Globals … we've taken at least three from their order book. There's lots of pressure on us now for early deliveries. The second thing is, we've added production spots — but we can add only so many at a time. Look, we're in this for 20 years, not three.

How many orders are now in for Global Expresses?

In excess of 60.

You hear that the market potential for these long-range jets is anywhere from 200 to 800 airplanes. What do you think?

Well, between the two of us [Bombardier and Gulfstream] there are 150 to 160 airplanes on order now, and it's still early. So maybe 300, I think. Also, calling them long-range is a misnomer. There'll be range when it's needed … other times the extra range capability is a safety factor. For example, on a 5,500-mile trip, you'll have 1,200 more miles to deviate for weather or delays. The Global will be 15 to 20 percent cheaper [than the G-V] to operate — not a lot more than a Challenger. Not to overdo it, but let's just say that we want to make sure it's not considered solely a long-range airplane. Let's say [Gulfstream's] order book is at 70 airplanes. For us to have 60 of 130 orders, that's fantastic. We'll beat them on speed, range, and cabin. And over a 10-year period, a Global owner will save $1 million in operating costs because of our aerodynamics and our wing.