The Mallard was the third aircraft type produced by Cornelius Aircraft.[1] The first two, the FreWing and the LW-1 were conventional in layout but unusual in using independently variable incidence wings for pitch and roll control. The wings of the Mallard could also be adjusted in the air,[1] [2] but they were of low aspect ratio with marked forward sweep. The trailing edge carried conventional ailerons near the tips and elevators close to the fuselage. The Mallard was also a tailless aircraft, in the sense of lacking a horizontal tailplane. The rest of the aircraft was conventional, with single fin and rudder and a side-by-side cockpit for two behind a flat four engine. The undercarriage was fixed and of the tailwheel type. Like other Cornelius designs, the sole Mallard was built by the Spartan Aircraft Company.[1]
The Mallard first flew on 18 August 1943, flown by Arthur Reitherman,[2] though some sources[3] suggest that most of the subsequent 18 flights were in the hands of the Romanian aerobatic pilot Alexander Papana. The first public flight was on 7 September 1943.[2] It was reported to have been 700 lb (320 kg) overweight[1] and there were plans to install a more powerful engine. The designer claimed that the Mallard was stall and spin proof, though the later loss of the much larger but similarly configured Cornelius XFG-1 in an irrecoverable spin has cast doubt on this.[4]