July 4, 2006 It takes but a glance at the Javelin personal jet to understand that it was born from the intense desire to offer military performance to the general aviation market. That was our intro in April last year when we first saw the Javelin, and subsequent stories in June, August and October charted the Javelin’s construction, flight testing and now we can report that the prototype testing has yielded several design changes (an increase in wing size, enhancement of wing lift devices, and improvement to the canopy opening mechanism) and with these last major design changes, the Javelin’s configuration is being frozen for production. At US$2.795 million (2005 dollars indexed), the Javelin offers jet fighter performance at a fraction of what you’d be likely to pay if you could buy a fighter jet … and that’s the biggest bonus because you can actually buy a Javelin if you’re prepared to stand in line for a year or two.
To achieve a lower stall speed, resulting in slower and safer approaches and landings, designers have increased the wing span by 1.85 feet and the wing area by 29 square feet. The wings have been further enhanced with Fowler flaps and leading edge flaps. Aerodynamicists expect these wing improvements to yield a 5 to 7-knot decrease in stall speed, lowering Javelin’s stall speed to 90 knots.
Engineers also implemented design improvements to the Javelin's canopy system. Under advisement from ATG’s Pilot-vehicle Interface Working Group, designers selected an aft-hinge canopy opening mechanism to replace the less conventional side-opening arrangement. Removal of the side hinges gives the new canopy a more aerodynamic profile, enables ground operations with an open canopy in winds up to 40 knots, and allows Javelin pilots to taxi with improved visibility and cockpit ventilation. The new canopy also features a gas spring and electric motor combination, which allows pilots to open and close the canopy with the push of a button.
Changes to the wing and canopy have resulted in a nominal weight increase and a small decrease the Javelin’s cruise speed to 500 knots. After a thorough review and acceptance by ATG engineering staff and executive management, the overall benefits of these final design changes were confirmed by a series of wind tunnel tests conducted at the University of Washington Aeronautics Laboratory in May.
Javelin executive jet (Mk-10)
Engines: two 1,800-pound thrust, turbofan Williams International FJ33 Seating capacity: two, tandem Cabin width: Canopy interior sills: 28.5 inches Cockpit interior width at elbows: 36 inches Maximum outside cabin width: 40 inches Maximum gross weight: 6,900 pounds Empty weight: 4,655 pounds Wing span: 25.1 feet Length: 37 feet Height: 10.5 feet Wing area: 149 square feet Wing load: 46 psf Takeoff ground roll (std day, SL, 6,900 pounds): 2,000 feet Balanced field (std day, SL, 6,900 pounds): 3,200 feet Maximum rate of climb: 9,000 fpm Time to climb to 41,000 feet (ISA, std day, 6,900 pounds): 17 minutes Cruise speed (ISA, std day, 5,100 pounds, 35,000 feet): 0.87 Mach, 500 KTAS, 575 mph Stall speed in landing configuration (6,900 pounds.): 98 KCAS Stall speed in landing configuration (5,380 pounds): 86 KCAS Approach speed: 120 knots (at maximum gross weight) Approach speed: 105 knots (at typical approach weight, 5380 pounds) Landing distance (std day, SL, 6,900 pounds, full flaps) Ground roll: 2,400 feet Over 50 feet: 4,000 feet Landing distance (std day, SL, 5,380 pounds, full flaps) Ground roll: 2,000 feet Over 50 feet: 3,400 feet IFR range (long range cruise speed): 1,000 nm Endurance: 3.5 hours Fuel capacity: 280 gallons Fuel consumption at mid-cruise weight Economy cruise (0.75 Mach at 45,000 feet): 73 gph High-speed cruise (0.86 Mach at 35,000 feet): 133 gph Certified ceiling: 45,000 feet Cargo or baggage: up to 200 pounds Price 2005: US$2.795 million (2005 dollars indexed, taxes not included)