“The idea is both scary and thrilling—one small engine that you depend on for four days to fly further than man has ever flown before."

Engine Mods Take Off

“There’s been 30 years of technological change incorporated in the Williams engines,” says Huffstutler. . . “We’ve got a great relationship with Williams.”

“For the Citation II, the biggest problem was the need to step climb to altitude. The FJ44 cures that problem,” says Jim Clifford of Clifford Development. “It’s hard to believe, but the Williams engines with FADEC don’t need thrust reversers on the Citation,” he says, adding that the accelerate-stop distance is reduced 18 percent. How can that be? “With the FADEC at ground idle on the squat switch, these engines can go to lower rpm, so the engine acts more like a speed brake. With the old fuel control you can only spool down so far because if you had to apply power, you might burn it up. In 25 years, the engines have just gotten better.”

The effortless acceleration and smooth jet buzz from the Williams turbofans will certainly sweeten the deal for any pilot contemplating a step up to jet power.

“When you watch the autopilot capture the altitude at FL370 and the airspeed build to well over 500 mph on fuel flows that would make an early Citation blush, when you consider the capability of this airplane to easily complete a 2,000-mile journey with little planning, the SJ30 impresses you as a serious business tool capable of restoring a few more useful hours to the lives of people who fly a lot.

“I concluded that jets should not be more expensive than turboprops. I also thought that people who bought turboprops really wanted jets but were put off by their high cost. That was the best market for business jets, if they could be made more efficient and affordable.” That was the starting point for what would become the SJ30 project. But first Swearingen’s vision of such an aircraft would need a much lighter, less costly jet engine. “I shopped all the engine manufacturers and finally met with Sam Williams who had developed a small jet engine rated at 1,800 pounds of thrust, which was eventually brought up to 2,300 pounds. It cost less than a turboprop, and that little engine actually made it possible to build the SJ30.”

Sino Swearingen SJ30-2

The smallest business aircraft with coast-to-coast range and real jet speed

“The key enabling technology for the SA30 would be the availability of a new engine, as it has always been throughout the history of powered flight. About the same time that Swearingen was freezing the basic SA30 design, Burt Rutan was completing tests of his all-composite, proof-of-concept Triumph business jet in Mojave, Calif. The Triumph was fitted with two revolutionary 1,800-pound-thrust, Williams International FJ44 high-bypass turbofans that were priced substantially lower, weighed considerably less and achieved better fuel economy than existing light turbofan engines. The FJ44 was the technological breakthrough for which Swearingen had been waiting to make possible the SA30. . . ““The aircraft stabilized at 435 KTAS fuel flow of 740 pph. That’s a specific range of 0.587 nm/pound—the best fuel efficiency we’ve yet recorded for a business aircraft cruising at this speed. . . ““The SJ30-2 is the fastest, most fuel efficient and long-range light jet in its class. . .”

“A Citation 525 operator had this to say of Williams’s factory support: ‘Walled Lake has turned out 10 engines for us on budget and on time, and loaners, parts and tools have been perfect.’ ”

"In April, the first A700 AdamJet flew to 41,000 feet and achieved a true airspeed of 340 knots, demonstrating the aircraft’s flight capabilities. ‘When they hit 41,000 feet, the A700 was still climbing at 1,500 feet per minute, which is unheard of in a light jet,’ Rick Adam said. ‘It looks like the airplane has lots of extra power.’ The A700 is a turbofan-powered, six-seat aircraft, driven by two Williams International FJ33 engines."

"Starting the SportJet is an extremely simple process thanks to the Williams FJ33-4A engine and the Full Authority Digital Engine Control... I was particularly impressed with the low cabin noise level even before efforts are made to insulate and control cabin noise... The engine is a dream powerplant."

“We are absolutely delighted with this [first] flight,” said Christian Dries, CEO of Diamond Aircraft, who flew the chase aircraft.  “The test flight went exactly as planned. What more could you ask for? Our crew did a fabulous job and we are very grateful for the support received from Williams, Garmin, Parker, Argotech and our other partners.” The D-JET is a 5 place luxury personal jet powered by the FADEC controlled Williams FJ33 turbine.

“A big plus for Citation Jets one and two

New Collins Pro Line 21 avionics suite is great, but the climb and cruise performance improvements steal the show

Instead of just adding full-authority digital engine controls (FADEC) to control and simplify operation of the engines on the CJs, Cessna took the opportunity to install new models of the Williams FJ44 family of turbofans. The new FJ44-1AP on the 1+ is rated at 1,961 pounds of thrust for takeoff, which is 61 pounds more than the previous engine. On the 2+ engine power is increased by 90 pounds per side. But the thrust gain is not the whole story. It’s the optimized design of the engines that makes the difference. . .

The performance the new engines deliver is wonderful, but nearly as nice is the ease of operation provided by the FADECs.  In the earlier CJs you were constantly fiddling with the thrust levers to set power on takeoff and throughout the climb. Hardly a minute would go by without need for an adjustment in N1 fan speed as the altitude changed. Now, with the FADECs, you simply push the levers to the takeoff detent, once safely up and climbing pull back to the maximum continuous power detent, and that’s it. In cruise you can use the max cruise detent, or set any intermediate power. The level of workload reduction is amazing, and particularly welcome in airplanes that are often flown with a single pilot. . .

The FADECs now reduce engine idle power to a level where the attenuators are not necessary. Elimination of the attenuators saves at least 24 pounds of weight and eliminates an entire system with its hydraulic lines, wires and switches. . .Despite the weight increases to both airplanes, runway performance actually improves. Required runway for takeoff and landing is reduced at least a little under all conditions. Part of the explanation for less runway at higher weights is the increased engine thrust for takeoff. But the engines also play a part in shortening landing distances because the FADECs reduce idle thrust, allowing the new airplanes to touchdown sooner without the residual idle thrust pushing them down the runway. . .

With no increase in fuel capacity both new CJs have longer range. . .”

“We have found the Williams FJ33 engine meets or exceeds our expectations in performance and fuel burn. The engine and Williams support have been flawless since we began flying the engines in July 2003.”

“. . . a beautiful flight. The FADEC-controlled Williams turbofan engines were exceptionally responsive, and the jet’s handling was very predictable and smooth.”

Linden Blue selected the [FJ33 for Spectrum] because it offers better high-altitude performance and superior fuel efficiency.”

“Williams Int’ls NBAA exhibit features its engines lined up in order of thrust. It’s an excellent illustration of technological trends. From the 1900-lb thrust FJ44-1 to the 3500-lb-thrust FJ44-4 ─ almost twice as powerful ─ the fan diameter increases by only a few inches. But the blade shape changes a lot ─ an indication of how the company advanced its Williams Wide Sweep technology from one engine to the next. No hollow blades here ─ the Williams fans are small enough to let the company hog the entire unit out of one titanium forging, which arrives at Williams’ Ogden UT factory looking like a giant silvery biscuit and leaves as a jewel-like fan.”

“After a tough competition, we selected Williams as our production partner because of their superior reputation, their advanced technology engines, and their commitment to product support for our high performance jet.”

“Let me say, that without a doubt the FJ44-2As were flawless in their performance. I personally monitored the engine performance during the trip and I must say, there was never any doubt the engines were dead on in all parameters. These are outstanding engines!”

“Williams International is a family-owned business that is a world leader in the design, development and manufacture of small gas turbine engines and their related technology. Their schedule performance has been outstanding. Over a one-year period, more than 20 different engine concepts and cycles have been analyzed and evaluated with NASA.”

“For his unequaled achievements as a gifted inventor, tenacious entrepreneur, risk-taker, and engineering genius in making the U.S.A. number one in small gas turbine engine technology and competitiveness, and for his phenomenal leadership in helping revive the depressed United States general aviation business jet industry.”

“In making lasting contributions to aviation and national defense over the last 35 years, Sam Williams has surely epitomized all the spirit and achievement of the Wright Brothers. His many insights, inventions, and innovations have proved to be vital steps along the path to aviation progress inaugurated by Orville and Wilbur Wright at Kitty Hawk 85 years ago.”

“I am pleased to congratulate you on your achievements in miniature engine technology which have won you the 1978 Collier Trophy of the National Aeronautic Association. In accepting this prestigious honor, you join a select group of aviation pioneers who, through personal endeavor and talent, have helped advance America’s technological leadership and scientific excellence.”