Boeing delivers its 5,000th 737 After a bumpy youth that it almost didn't survive, jet ages into a 'timeless classic'

Boeing employees sit in the first-class section of a sales mockup of the 737 jetliner, about a year before the 737's maiden flight. Boeing employees sit in the first-class section of a sales mockup of the 737 jetliner, about a year before the 737's maiden flight. Photo: /Seattle Post-Intelligencer Photo: /Seattle Post-Intelligencer Image 1 of / 3 Caption Close Boeing delivers its 5,000th 737 1 / 3 Back to Gallery

With the canary yellow and silver jet with black trim back on the ground after its maiden flight, Boeing President Bill Allen was asked about the future of the 737.

The company's newest jet had taken off from Boeing Field two hours earlier and, after cruising around Puget Sound, landed at Paine Field in Everett, where reporters gathered around a smiling Allen.

It was April 9, 1967.

Could Boeing sell a few hundred planes? someone asked Allen.

"A few hundred?" Allen replied in mock amazement. "You are being conservative."

Today, Boeing will deliver its 5,000th 737 to Southwest Airlines, the world's biggest low-cost airline,which tied its fortunes to a jet that almost didn't make it.

Last year, Boeing sold 575 of the single-aisle jets. It was the first time more than 500 orders had been placed in one year for any Boeing commercial jetliner. Boeing has 45 orders so far in 2006, which pushes the 737 backlog to 1,154 planes that have been ordered but not yet built.

"It's a timeless classic," said Richard Aboulafia, senior aviation analyst with the Teal Group, an industry consulting firm.

"The baby Boeing reached adulthood very successfully."

No other commercial jetliner made by Boeing, Airbus or the former McDonnell Douglas has achieved such widespread popularity.

More than 4,100 737s are in service around the world, with 541 operators. The plane has carried an estimated 12 billion passengers more than 65 billion nautical miles.

An estimated 1,250 737s are in the air at any time.

It has been an amazing run for a plane that some Boeing executives thought should never have been built, and that others thought should have been built in Wichita, Kan.

Nearly canceled before adolescence when sales slowed to a trickle, the plane nicknamed "Fat Albert" by some pilots because of its stubby shape pushed its way into Boeing's history book, and its heart, with one tiny order at a time, usually in some faraway country.

The plane that would become the 737 got under way with a study authorized by Allen in 1964.

By then, Douglas Aircraft Corp. in Long Beach, Calif., was already working on a short-haul twinjet, the DC-9. It first flew in the summer of 1966.

Also coming into service was the British BAC 111 twinjet.

As the pre-launch engineering progressed, Boeing's sales force went looking for customers. The best bets looked to be Eastern and United airlines and the German carrier Lufthansa. All three were also considering the DC-9.

On Feb. 19, 1965, the Lufthansa board gave the OK to order 21 of the 737s after getting Allen's promise that Boeing would not drop the program for lack of orders.

Within a week, Eastern ordered the DC-9.

In April, though, United ordered 40 737s and took options on 30 more.

There was much debate within Boeing whether the plane should be built in Seattle or in Wichita.

Seattle won, although Wichita wound up building major parts of the plane, including the fuselage. But the Renton plant was too busy with 707 and 727 production. So Boeing purchased a few acres on East Marginal Way across from Boeing Field. Production of the 737 started there, in what was known as Building 14-01. Production moved to the Renton plant in late 1970.

Only 30 of the 737-100 models were ever built.

United needed a slightly larger plane, so Boeing stretched the body by 6 feet to accommodate 115 passengers rather than the 102-seat configuration for Lufthansa.

In 1970, only 37 planes were ordered.

Serious consideration was given within Boeing to cutting its losses and pulling the production plug on the 737.

In an interview with the industry publication Flight International before his recent death, Jack Steiner, the legendary Boeing airplane designer who had insisted the 737 have the same fuselage cross-section as that of the 727, revealed that Boeing was so desperate it considered selling the entire 737 program to the Japanese aerospace industry.

"I can't tell you we would have gone through with it," he told the magazine, "but the intention was there. We were broke."

The early 737 design called for a T-tail with the engines mounted on the rear fuselage. Joe Sutter, who would soon go on to fame as chief engineer of the 747, came up with the idea of mounting the 737 engines hard under the wing.

During the first few years of 737 production, Boeing concentrated on overseas sales. Because the 737 could operate from unimproved runways -- gravel, dirt or grass -- the plane found a home in Africa and later Canada.

Gradually, the 737 order book grew. But those orders came in small numbers, with one or two airplanes sold at a time.

One such order came from a new low-fare carrier, Southwest Airlines, which took three white-tail 737-200s on a conditional sales agreement -- Boeing financed 90 percent of Southwest's costs. A white-tail plane is one that has been built but has no customer.

Today, Southwest has nearly 500 737s in its fleet.

By 1978, 737-200 orders stood at 543 planes, placed by 70 customers. That was better than the DC-9.

In 1984, a new 737 was delivered to launch customer Southwest. It was the 737-300, the first of what became the "classics." It was longer than the 737-200 and had new engines that were less noisy and more fuel-efficient.

The stretch 737-400 for launch customer Piedmont Airlines came along in 1988, followed by the shorter 737-500 model for Southwest in 1987.

In the 1990s, Boeing began talking with Southwest and other airlines about a significantly improved 737 with greater range and operating efficiency. Those talks would lead to the development of the "next generation" family of 737s. Southwest took delivery of the first, the 737-700, in 1997. Since then, Boeing has developed the 737-600, 737-800 and 737-900.

There's more to come. Boeing is developing a variant of the 737-900 that will seat up to 215 passengers in one class and a variant of the 737-700 with more range. With up to nine optional auxiliary fuel tanks and optional blended winglets, the 737-700ER will be capable of flying up to 5,510 nautical miles.

The 737 already has the range to fly non-stop across the United States and across the Atlantic.

"It would have been inconceivable years ago there would one day be versions of the 737 that could fly 6,000 nautical miles," said Aboulafia, the analyst.

Modified versions of the 737 are sold as private business jets. The military likes the 737, too. It is being developed as an airborne early warning and control plane for Australia and as a submarine hunter for the U.S. Navy.

But the 737 has serious competition from Airbus. The Airbus A320 single-aisle family of jets has been winning at least 50 percent of the market against the 737. Airbus sold more than 900 of its single-aisle jets in 2005.

As the battle continues, both airplane makers are studying an all-new replacement for their single-aisle offerings. Boeing's 737 replacement could be ready around 2012 to 2015, Boeing executives have said. It will have a composite airframe like the 787 Dreamliner.

A couple of thousand more 737s could roll out of the Renton plant before that replacement plane takes flight.

The last of the 737 classics was rolled out of the Renton plant on Dec. 9, 1999.

Among the Boeing executives who spoke that day was then-Chairman Phil Condit, who appeared before several thousand current and former Boeing employees at the rollout ceremony.

"There are a lot of people a number of years ago who would have taken bets in large amounts with phenomenal odds that we would not be here today," he said.