PRESS RELEASE

October 12, 2004

New Engines and More for Lear 25

LAS VEGAS, NEVADA -- by Kim Rosenlof-- Learjet 20 series airplanes will soon have a new lease on life- thanks to an Edmond, Okla.- based company that has completed a major engine, avionics and aircraft systems upgrade to a Learjet 25.

The upgrade, which results in a "virtually new" aircraft called the SpiritLear, incorporates Williams FJ44-2C engines; revitalized pressurization, hydraulic, electrical and fuel systems; and RVSM-compliant avionics. According to Calvin Burgess, president of Spirit Wing Aviation, the $1.8 million SpiritLear upgrade, expected to obtain an FAA STC by the second quarter of next year, is not simply an old airframe refitted with new engines.

"As much as this is an engine refit, it's also an aerodynamic cleanup," Burgess said yesterday during a press conference here at NBA'04. "The Lear had a real problem with the engines being placed too close to the wing and the fuselage," he said. "We moved the engines out four inches and back 16 inches." According to Burgess, this repositioning decreases drag induced by air flowing between the engine shrouds and the fuselage at supersonic speeds that created sonic shocks and slowed the aircraft. Testing has shown an added benefit of increased engine-induced airflow that improves lift over the inboard portion of the wing.

Williams modified the FJ44-2C engines used on the Spirit to allow thrust at idle to be reduced to 100 pounds, allowing shorter landing distances. It also incorporated the FJ44-3 power turbine sections into the SpiritLear's engines to provide more thrust under high-altitude, hot-outside-air-temperature conditions. The engines meet Stage 3 noise requirements and result in a faster, more economical and longer range Learjet 25.

"We increased the range 70 percent with 22 percent less fuel on board," said Burgess. "The flight here from Oklahoma City took two hours, 20 minutes using 250 pounds of fuel at 0.78 Mach cruise at 35,000 feet." Ferry range for the SpiritLear has been increased from 1,150 nm for the stock Learjet 25D to 1,808 nm for the SpiritLear, while fuel burn has decreased from 1,565 pounds per hour to 860 at high-speed cruise (440 knots at 41,000 feet). According to Burgess, although flight testing has been conducted at Mach 0.827 cruise speed, Spirit Wing is leaving the published maximum cruise speed at the original model's Mach 0.81 for safety reasons.

The SpiritLear upgrade also incorporates several pressurization system modifications that increase the overall safety of the aircraft. Bleed air is used to provide full time wing and engine nacelle deicing, and additional automatic emergency and manual outside air redundant pressurization systems have been added to the aircraft. Conduction flight tests at approximately the same time as Sino Swearingen's flutter-induced accident that killed test pilot Carroll Beeler last year, Spirit Wing also decided to conduct flutter tests of the SpiritLear to Mach 0.87 and made some changes per the flight test results.

"The aircraft now flies smooth as glass," Burgess said. "We've had to do a complete flutter rework on this plane. No other Lear has had a full flutter test that we know of."

The general cost of converting an existing Learjet 25D to the SpiritLear upgrade is $1.8 million, which does not include Spirit Wing's RVSM-compliant avionics package or upgraded paint and interior. For potential owners who do not have an airframe for conversion, the entire package costs approximately $2.2 million.

Keeping its development and flight testing relatively quiet until NBAA 2004, Spirit Wing has completed more than 85% of its flight testing and has just recently signed three authorized service centers: West Star Aviation of Grand Junction, Colorado; Banyan Air Service of Ft. Lauderdale, Fla.; and General Dynamics Flight and Aerospace Research unit in Niagara Falls, N.Y.

Although Spirit Wing has already accepted four orders for the SpiritLear, Burgess said the company is not looking for funding and the SpiritLear project is debt free.

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