The Learjet 31 honored both pocket-rocket legacy and the Spartan cabin spir

Learjet 31A

When Bill Lear created the Learjet in the early 1960s, he envisioned a small, fast and ­simple airplane, a concept the marketplace embraced. His 20-series and the slightly elongated 30-series ­aircraft that followed sold briskly for more than 20 years, until long after he had left the company. In the late 1970s, new owner Gates Learjet began work on the ­bigger, midsize Model 55 that mated the wing of the Learjet Model 28/29 Longhorn with an expanded Model 35 fuselage. The conglomeration yielded a 70-inch-tall "stand-up" cabin, but it was basically a parts airplane as opposed to a clean-sheet-of-paper design. The brakes and tires were too small and the engines needed more puff. As a result, the 55 could be a runway hog, especially in hot temperatures, and stopping on short pavement without thrust reversers was an adventure.

Bombardier bought Learjet in 1990 and set about fixing the 55's problems, but it didn't sell well and the manufacturer ultimately replaced it with the ­evolutionary Model 60. Subsequently, Bombardier introduced several other successful models, including the Learjet 40 and 45. It is currently developing the ambitious, all-composite Learjet 85, an aircraft poised to create a market niche between midsize and super-midsize.

These airplanes are competent, even wonderful in many ways. But aside from the rake of their windshields, they just aren't Learjets to me in the classical sense. The cabins are too big and too comfortable. Some even have lavatories with doors that close and external luggage compartments that can swallow golf bags.

It's like going to McDonald's for a latte or driving a Porsche sedan. Sure, you can do these things, but they just seem wrong. Riding in the back of a Learjet once meant trips to the chiropractor and exercising bladder control, suffering and even trading a certain amount of dignity for the ultimate in aviation cool: speed. In those days you didn't fly in a Learjet, you wore it.

The Learjet Model 31 series, which was produced from 1988 to 2002, fits in this latter category. The 31 mated the tube of its immediate progenitor, the Model 35/36, to the high-performance wing of the short-lived Model 28/29 "Longhorn." In so doing, the 31 honored both pocket-rocket legacy and the Spartan cabin spirit of those original 1960s Learjets. The 31's Procrustean ­cabin cross section: height 4.35 feet, width 4.95 feet. Cozy. No galley. And you really don't want a coffeemaker on this airplane, anyway, because there is no lav. (There is a chemical bowl under one of the seat cushions for absolute emergencies.) Fill up the seven ­passenger seats and everyone can bring...briefcases. On early serial numbers, there's only 30 cubic feet of luggage space and it is inside the 12-foot-long cabin. (Later serial numbers incorporated the externally loaded Raisbeck aft fuselage locker, which quadrupled baggage space.)

According to Bombardier, 262 Lear 31s were built and, like any aircraft with a long production run, it ­appeared in several versions. The "straight" 31s were first out of the gate. They feature antique analog avionics and an alcohol windshield de-icer. Bombardier built 38 of those. Later there also would be an extended range or "ER" variant that carried 75 extra gallons of fuel, yielding 30 minutes more flying time or about 175 nautical miles of additional range. However, the bulk of production was the Model 31A, which began appearing in 1991.

"The difference between a 31 and a 31A is significant," noted Bombardier Learjet customer-service representative Jack Kramer.

He's right. The 31A's improvements include ­electric windshield de-icing and a digital Bendix/King avionics suite that continues to garner pilot praise and has stood the test of time. A year 2000 block change further improved the aircraft, adding full authority digital engine control (FADEC), much-needed two-zone climate controls and increased takeoff and ­landing weights. The 31A is very much a pilot's airplane with good directional control, crisp handling, fastest-in-class speed and the ability to fly substantially outside the ­approved envelope (not that you should). The 31A can cruise at 51,000 feet and it excels on short runways.

An available $110,000 package (average price, installed) of performance enhancements from Raisbeck Engineering called "ZR Lite" significantly boosts the 31A's already impressive numbers. It improves the wing's aerodynamics by recontouring the flap's trailing edges. According to Raisbeck, this increases fuel economy 8 to 14 percent and range 11 percent; boosts speed .02 Mach at equivalent power settings; reduces time to climb; and yields a quieter cabin. Raisbeck has sold 36 ZR Lite packages to Lear 31 operators.

Even though the 31 is getting along in years, ­operators continue to add other upgrades, according to Brad Lennemann, a service and sales representative at Duncan Aviation in Lincoln, Neb. These include precision wide area augmentation system (WAAS) instrument approach ­capability ($140,000), cabin Wi-Fi via the Aircell Axxess ­system ($125,000 to $150,000), LED cabin lighting ($50,000 and up) and new paint and interior ($150,000 to $190,000).

Many of these aircraft also are coming up for large and potentially expensive inspections. Landing gear needs to be inspected every 6,000 landings ­(average cost $90,000 to $120,000); there's also a four-week-long inspection every 12 years ($200,000 to $250,000). Lennemann said Lear 31 owners generally do their upgrades while their aircraft are down for such inspections and continue to reinvest because of their airplanes' durability and enduring value. "They are cheap to fly for what they do. They just fly and they don't break."

How tough is a 31? For the better part of two decades, Wal-Mart operated 14 Lear 31s and 31As, many of them acquired used. It flew each an average of 750 to 1,000 hours per year, shuttling managers from its Arkansas headquarters to locations in far-flung store network. During that time, the company's earnings-per-share tripled, its revenues quintupled and its net income increased tenfold. Last year it had revenues of $408 billion and it is now the world's largest company.

Can you credit its Learjet fleet for this performance? Of course not.

But having the aircraft didn't hurt.