Linden S Blue, CEO and chairman of Spectrum Aeronautical LLC
and a consummate aviation futurist, took the wraps off his $3.65-million, 400+
knot, twin-turbofan Spectrum 33, Tuesday afternoon.
Blue, who also currently serves as vice-chairman at San
Diego-based General Atomics, and his son Austin own Spectrum Aeronautical, a
light jet start-up firm based in Encinitas, CA. Spectrum 33 will be a 7,300 lb
MTOW light jet, powered by twin 1,560-pounds-thrust Williams International
FJ-33-4 engines. To be certified for single-pilot operation, the aircraft will
seat two in the cockpit and five to six passengers in the main cabin. The
interior will have almost as much volume as the cabin of a Citation CJ2+,
including a full-width, fully-enclosed aft lavatory. With four occupants
aboard, Spectrum 33 will be able to fly 2,000 nmi and land with NBAA IFR
reserves, Blue claims. It also will burn less than half the fuel of a CJ2+,
according to Blue.
"We didn't want to have an airplane any smaller than the
best-selling light jets in the market. That set the cabin diameter," Blue said.
"After that, it was only a question of how many seats to include. But, I also
wanted an airplane that I personally could afford to fly. It had to be built of
composites because you just can't get the (operating) economics out of aluminum
because you can't get the weight down low enough."
Of course, weight reduction is the key to boosting fuel
efficiency, improving runway and climb performance, and reducing operating
costs. Spectrum 33 will have about the same external dimensions as a CJ2+, but
the basic fuselage and wing structures together weigh
just 615 lb. Blue estimates that Spectrum 33's single-pilot
BOW will be 3,820 lb. The wing tanks will hold 2,771 lb of fuel. The aircraft
will be able to climb directly to FL 450 and it will have a cabin altitude of
6,000 ft. Up front, Spectrum 33 will feature a three-screen, large-format
display integrated avionics system. Avidyne will supply the avionics for the
prototype, but Blue is looking at all options for production aircraft.
How will Blue achieve his performance goals for Spectrum 33?
Larry Ashton, founder of Rocky Mountain Composites (RMC) in Spanish Fork, UT
and long-time Blue associate, actually is spearheading the engineering effort.
Spectrum Aeronautical owns a majority interest in RMC. Ashton and Blue have
collaborated for more than 20 years on various projects, such as the Beech
Starship and Learfan, plus sub-contracting work for Boeing, Monogram and
General Atomics Aeronautical Systems. Ashton is the Spectrum 33's main designer
and his initials adorn the tail of the prototype, N332LA.
Ashton put Spectrum 33 on the composite design equivalent of
the Atkins Diet, not unlike the Boeing 787. The airframe is 99% carbonfiber
muscle and virtually no filler. All but one percent of the fattening
carbonfiber/core/carbonfiber sandwiches have been eliminated. Ridding the
aircraft of composite sandwich structures not only reduces weight by one-third,
it also eliminates most of the hand lay-up and resulting human error, along
with hundreds of hours of manufacturing labor. Almost all of the airframe components
are fabricated using a computer-controlled filament winding process called
Fibexª, a closely guarded proprietary process that eliminates most hand lay-up
of components. The entire fuselage pressure vessel, for example, can be
fabricated in less than five hours, not including curing time. Assembly of
various sub-components into the final airframe is the only part of the process
that requires hand labor. Final assemblies are high pressure co-cured in a low
temperature oven.
First flight of the prototype was scheduled for
mid-September 2005, but it's been pushed back to mid-January 2006 because of
the complexity of systems integration. If all goes according to plan, three to
four production-conforming Spectrum 33 flight test aircraft will be flying by
the end of 2006. Static and fatigue ground test articles also will be built
next year. Blue plans to complete ultimate load testing of the static test
article prior to first flight of a production-conforming flight test aircraft.
FAA Part 23 certification is slated for late 2007 or early 2008.
Meet Linden Blue, Austin Blue and Larry Ashton, plus other key
members of the Spectrum Aeronautical LLC team at Booth 1672. Look for a full
report on Spectrum 33 in the December 2005 issue of Business & Commercial
Aviation magazine.
