Beck-Mahoney Sorceress

A reverse-stagger biplane, Sorceress represents the state of the art at the time of its design and remains one of the great design classics of air-racing within the United States. Lee Mahoney, the designer, had experience in airframe construction with composite materials, metal-to-composite bonding technologies, and computational fluid dynamics, applying his experience to design Sorceress, and achieve success with several noteworthy design features, including: Use of engine exhaust air flow forms a Coandă effect-bonded laminar flow over the fuselage, increasing rudder efficiency by several orders of magnitude. Mahoney had originally designed the fuselage so that a fin would not be necessary - the fuselage would have ended with a rudder, but his partners however preferred a more conventional treatment, giving Sorceress one of the smallest conventional fins of any racing biplane to date. The aerofoil sections of the wings are designed as mirror image 'vanes' of symmetrical section - they interfere with each other's flow in a manner which provides very high efficiency in turns, whereas one vane-set/wing begins to lose efficiency, the other gains more, allowing for extremely high lift in turns with minimal loss of velocity Sorceress gains a great deal from composite bonding, with one of the first airframes to demonstrate almost perfect streamlining combined with very great strength; the wing interplane struts are for show only, Sorceress being capable of flight without them, but racing rules require them. ==Controversy==

Sorceress was designed within the rules of the ARPA Biplane class of 1965 and conformed to them without deviation, however, by 1972 competitors lobbied successfully to have Sorceress banned from competition. Items of contention included: The original configuration used a limited model of the Teledyne Continental O-360, a commonplace engine, but oil sump configuration and the use of electronic ignition failed scrutiny checks. The original undercarriage suffered collapse on several occasions and the Sorceress team were instructed to improve the undercarriage with stronger struts and larger wheels. The wing area of the original wings was deemed excessive and had to be reduced. The lower wing outboard of the interplane struts was removed and swash-plates fitted to the tips. Lee Mahoney took a lot of these criticisms, rule changes and comments personally, speaking about his experiences in an interview with 'Air Progress' magazine: Not withstanding the negative early experiences, Sorceress retains her claim to being the most technologically advanced biplane of any sort ever constructed, and her racing history subsequent to the controversy has gone on to prove the faith and skill of her designer, backers, and pilots. ==Results and records==

Sorceress placed in the following Reno Air Races, racing as #89: • 1970: Biplane Consolation, 7th place, , pilot: Lee Mahoney (crossed the finish line first, but automatically moved to last as it was racing as a fill-in). • 1971: Biplane Gold, 2nd place, , pilot: Paul Deschamps • 1972: Biplane Gold, 1st place, , pilot: Don Beck • 1973: Biplane Gold, 2nd place, , pilot: Don Beck • 1974: Biplane Gold, 2nd place, , pilot: Don Beck • 1975: Biplane Gold, 1st place, , pilot: Don Beck • 1976: Biplane Gold, 1st place, , pilot: Don Beck • 1980: Biplane Gold, 8th place, , pilot: Don Beck (crossed finish first, disqualified for illegal passing) • 1982: Biplane Gold, 3rd place, , pilot: Don Beck • 1983: Biplane Gold, 2nd place, , pilot: Don Beck Sorceress set a number of speed records in the Sport Biplane Class, including: • 190.48 mph, qualifying heat record, 1970 Reno Air Races • 189.723 mph, championship race record, 1972 Reno Air Races • 202.153 mph, championship race record, 1976 Reno Air Races ==Specifications==