Al Backstrom Backstrom Flying Plank EPB-1C

Glider Reg. Number: N19C

1964

Design & Development

The Backstrom EPB-1 Flying Plank is an American mid-wing, single seat, tailless glider that was designed by Al Backstrom, with assistance from Phil Easley and Jack Powell in 1954 and made available as plans for amateur construction.

The Flying Plank was intended to be an aircraft that could be built at home, that would be of minimum size and yet still provide reasonable soaring performance. The prototype Plank featured tip rudders and was used for drag-reduction tests conducted at Mississippi State University before it was retired. The EPB-1 designation indicates the design team's last names.

The "A" model was described in the plans sold and retained the twin tip rudders of the EPB-1, although some were built with a single fin and rudder assembly attached to the cockpit rear such as the EPB-1C. At least one two-place side-by-side seating version was built in Australia, and another as a motor glider. The standard wingspan is 25 ft (7.6 m), but versions have been built with spans up to 30.5 ft (9.3 m).

Specifications

General characteristics

Crew: one
Wingspan: 25 ft 0 in (7.62 m)
Wing area: 100 sq ft (9.3 m2)
Aspect ratio: 6.25
Airfoil: Abrial 15%
Empty weight: 150 lb (68 kg)
Gross weight: 350 lb (159 kg)
Performance

Maximum glide ratio: 20:1 at 60 mph (97 km/h)
Rate of sink: 210 ft/min (1.1 m/s) at 47 mph (76 km/h)
Wing loading: 3.5 lb/sq ft (17 kg/m2)