Up to OJB's Aircraft List Wing Walker I have never seen wing walking at the air show before. Peggy Krainz has been wing walking for about 10 years and she has done about 600 displays in that time. The view from the top of the wing must be quite impressive, especially when flying upside down or in vertical flight as in the photograph!  Note that the aircraft at the show was not a standard Stearman. Its specs are shown in brackets below. Boeing Stearman Specifications:
Crew: two, student and instructor
Length: 7.39 m
Wingspan: 9.81 m
Height: 2.79 m
Wing area: 27.59 m^2
Empty weight: 878 kg
Max takeoff weight: 1,232 kg
Powerplant: Continental R-670-5, 164 kW (Pratt and Whitney radial, 336 kW)
Maximum speed: 198 km/h (240 km/h)
Cruise speed: 171 km/h
Range: 808 km
Service ceiling: 3,415 m
Rate of climb: 256 meters/min Sources: Wikipedia, Warbird Alley, Warbirds Over Wanaka 2010 Programme. | 
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