|Jurca M.J.7. Gnatsum|
|Role||Homebuilt near scale Replica Warbird|
|Variants||Falconar SAL Mustang|
Design & Development
The Gnatsum (Mustang spelled backward) is one of many wooden homebuilt designs from Romainian designer Marcel Jurca. Jurca, a Henschel Hs 129 pilot in WWII, expanded his warbird replica designs to include the allied P-51.
The Gnatsum is a low-wing cantilever monoplane an enclosed single-seat cockpit and manually retractable tailwheel landing gear based on that of the Jurca Sirocco. Suitable for a number of engines around 200 hp, plans for the Gnatsum are available as the 2/3 scale MJ.7 and the 3/4 scale MJ.77, as well as the M.J.70 full-size representation. All versions are constructed from wood with fabric covering, and manufacturing rights to the kit aircraft were acquired by Falconar Avia. although the company does not currently offer the aircraft design.
Some of the engines suitable for the MJ.7 Gnatsum series are:-
- 200-hp Ranger 6-440C-5 inline engine
- 125-hp Menasco C4
- 130-hp de Havilland Gipsy MajorI
- 125 to 160-hp Rambler aluminum block in-line 6
- General Motors aluminum V-8
- 2/3 scale variant
- MJ-7S Solo
- Single-seat advanced trainer version of MJ-7, the under-belly scoop inherited from the Mustang design was removed.
- 3/4 scale Mustang variant that requires an engine of 250 to 600 hp (186 to 447 kW).
- Full-scale variant (under development in 1996)
Specifications (Jurca M.J.77 Gnatsum)
Data from 
- Crew: 1 Pilot
- Capacity: 1 (small) passenger
- Length: 6.53 m (21 ft 5 in)
- Wingspan: 8.43 m (27 ft 8 in)
- Wing area: 13.5 m2 (145 sq ft)
- Empty weight: 998 kg (2,200 lb)
- Gross weight: 1,297 kg (2,860 lb)
- Fuel capacity: 50 U.S. gallons (190 L; 42 imp gal)
- Powerplant: 1 × Geschwender , 260 kW (350 hp)
- Propellers: 4-bladed
- Maximum speed: 465 km/h; 251 kn (289 mph)
- Cruise speed: 370 km/h; 200 kn (230 mph)
- Stall speed: 105 km/h; 56 kn (65 mph)
- Range: 805 km; 434 nmi (500 mi)
- Rate of climb: 7.6 m/s (1,500 ft/min)
- Aircraft of comparable role, configuration and era
- Titan T-51 Mustang
- W.A.R. P-51 Mustang
- Linn Mini Mustang
- Bonsall DB-1 Mustang
- FK-Lightplanes SW51 Mustang
- Papa 51 Thunder Mustang
- "All these planes you can build from plans". Popular Science: 99. June 1970.
- Nick Stasinos (February 1972). "Marcel's Mini Fighters". Plane & Pilot.
- Sport Aviation: 35. Aug 1965. Missing or empty
- Air Trails: 59. Summer 1971. Missing or empty
- Bayerl, Robby; Martin Berkemeier; et al: World Directory of Leisure Aviation 2011-12, page 94. WDLA UK, Lancaster UK, 2011. ISSN 1368-485X
- "Jurca M.J-77 Mustang (75%)". Pilotfriend.com. Retrieved 2012-09-26.
- Taylor, Michael J. H. (1989). Jane's Encyclopedia of Aviation. London: Studio Editions. p. 547.
- Manufacturer's website