GE90 115B Jet Engine

Powers the B777 Jet Liner

127,900 Pounds of thrust

Over 100,000 HP

You stow your luggage, settle into your seat and lean back as your plane speeds down the runway and lifts into the sky. Higher, faster, farther with less fuel is the airline industry's mantra. Driving the industry's progress is the machine that revolutionized aviation: the jet engine.

Consider the behemoths that power Boeing's big 777, which the Guinness Book of Records certifies as the most powerful commercial jet engine ever built. According to Guinness, General Electric's GE90-115B generated 123,000 pounds of steady-state thrust during its initial ground testing in 2001, a record it would later break.

To put that achievement in historic perspective, the HE S-1, the hydrogen-powered turbojet prototype developed by German engineer Dr. Hans von Ohain and built by the legendary warbird manufacturer Ernst Heinkel in 1937, cranked out a modest 250 pounds of thrust.

Seeing the potential, the Luftwaffe seized the opportunity well ahead of the Royal Air Force, scrambling jets into the air during the final months of World War II.

After the end of the war, civilian applications of jet transport quickly became apparent. While an assortment of commercial jets took wing during the 1950s, the real success only arrived in 1958 with the introduction of Boeing's 707. Since then, progress has been led by bigger and more powerful engines.

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Boeing's 777-300ER can carry as many as 365 passengers up to 7250 nautical miles. On still longer routes, airlines will operate the 777-200LR, which can carry 301 passengers 8865 miles.

Hauling that much weight for such great distances takes plenty of power for a twin-jet aircraft. Under normal operations, the GE90-115B is rated at 115,000 pounds, yet it has shattered its Guinness record, reaching 127,900 pounds of thrust during tests in late 2002.

Unlike von Ohain's original turbojet, the GE90--and most of its competitors--is a turbofan. The basic principles are similar: Jets draw in outside air, which is compressed, mixed with fuel, then burned and exhausted at high speed, producing thrust. Turbo-fans add an additional set of spinning blades in front of the compressor. Much of that air bypasses the engine core, adding plenty of extra thrust without using more fuel.

Titanium blades would simply be too heavy in an engine this size. Composites provide the key. Extremely light, durable and efficient, they're used for the front fan blades (see illustration, right). Their huge size allows them to run relatively slowly, which is a critical factor for noise control. That is good news for those living near urban airports.

Composite blades require less torque to turn. And they're incredibly resilient. During their first five years in service, smaller versions of the GE-90 have had dozens of bird ingestion "events," yet they've remained fully serviceable.

In a business where profits turn on shaving pennies from the cost of transporting each passenger, the next generation of big engines spells good news for airline operators. General Electric says the GE90-115B turbofan offers the greatest propulsive efficiency of any commercial transport.