Engineering:HPK SP-1

From HandWiki
HPK SP-1
Role Homebuilt aircraft
National origin United States of America
Manufacturer HPK Aircraft Associates, a division of Engle Flying Service, Inc.
Designer Harold Hayden, Art Payne, Robert Kinney, Norman R. Benner
First flight 23 August 1957
Introduction 1957
Number built 1

The HPK SP-1 a.k.a. "Some Pisser-1" is a single seat homebuilt aircraft.[1]

Design and development

Engle Flying Service members, Harold Hayden, Art Payne, Robert Kinney, and Norman R. Benner developed the HPK SP-1 over the course of five years. Plans for a two-seat side by side, and four seat variants were not completed.[2]

The SP-1 is a single-place, all-metal, low-wing aircraft with conventional landing gear and partial span split trailing edge flaps. The cowling is from a Piper Tri-Pacer.[3]

Operational history

The aircraft was built and tested at Three-M airfield in Pennsylvania, home of Kaiser-Fleetwings Company.[4] The prototype has been registered for over 50 years.[5]

Specifications (HPK SP-1)

Data from sport aviation

General characteristics

  • Length: 19 ft 1 in (5.82 m)
  • Wingspan: 25 ft (7.6 m)
  • Height: 8 ft 1 in (2.46 m)
  • Wing area: 99 sq ft (9.2 m2)
  • Airfoil: 4412
  • Empty weight: 1,300 lb (590 kg)
  • Powerplant: 1 × Lycoming O-235-C1 , 115 hp (86 kW)
  • Propellers: 2-bladed

Performance

  • Maximum speed: 140 kn (160 mph, 260 km/h)
  • Cruise speed: 126 kn (145 mph, 233 km/h)
  • Stall speed: 43 kn (50 mph, 80 km/h)
  • Wing loading: 13 lb/sq ft (63 kg/m2)

References