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Jurca MJ-100 Baby Spitfire
Bob Deford, EAA 314241, of Prescott, Arizona, built a full-scale replica Spitfire Mk IX of wooden construction, powered by an Allison V-1710 engine turning a DC-3 propeller. He and a friend went to work on the plane in 1996 and spent eight years to finish it. N1940K was completed in 2003.
N1940K
French engineering studies yielded a welded steel tube fuselage structure that could support an Allison V-1710 engine capable of generating 1,400 hp on takeoff. The steel tube internal fuselage structure is covered with a non-load-bearing aluminum skin riveted in place. The wing spar is made of laminated Douglas fir planks hosting wooden ribs. The whole skeletal structure of the wing is sheathed in 3/16-inch aircraft plywood.
The unattached skins are soaked from both sides, and then placed flat in the sun just long enough to dry the surfaces while keeping the interior moist. The inside surface of the sheet next received a rolled-on coat of epoxy before being aligned on the wing and hit with a staple gun. The plywood drys, conforming to the airfoil shape of the wing. Fiberglass topped with epoxy finishs the job, giving the wing protection and smoothness.
The main landing gear uses T-6 Texan hydraulics and T-28 wheels and brakes support tires normally found on a business twin. The main gear struts are newly made. Instead of using oleos for shock absorption, Deford worked with a spring vendor to come up with heavy springs that cushion the load of landing without the complexity of oil shocks, giving the gear no maintenance. He said the result is a ground ride that "hops like a real Spitfire," based on his review of Spitfire ground handling films.
The Allison engine is from a P-39 Airacobra and Hamilton Standard propeller from a DC-3.
 The Allison uses a downdraft carburetor with a duct running from the traditional Spitfire chin scoop back to the firewall and up to the top of the cowled Allison.
His has an original-type stick that pivots at mid-stick for roll, and says it could not work otherwise because the Jurca cockpit is a bit more narrow than the original due to straight tubing in the cockpit area. The original cockpit bows outward a bit from the canopy opening so, if the entire stick pivoted for roll at the floor, he would have very little roll control throw availble.
 MJ-100 (100%) Engine: Allison V-12, 1100 hp
Wing span: 10.97 m
Wing area: 22.26 sq.m
MAUW: 2295 kg
Empty weight: 1770 kg
Fuel capacity: 568 lt
Max speed: 571 kph
Cruise speed: 483 kph
Minimum speed: 100 kph
Climb rate: 17 m/s
Seats: 1
Plan price (1998): US$3750
Deford N1940K Engine: Allison V-1710
Prop: 3-blade, ex-DC-3 Wingspan: 36 ft 10 in
Top speed: 300 mph
Fuel capacity: 100 USG
ROC: 3500 - 4000 fpm Load factor: +9 g / -6 g Endurance: 1 hr 30 min
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