The Long Henderson Longster HL-1 is an American aircraft that was designed by Leslie Long and Ivan Diggs for homebuilt construction.
The Henderson Longster is a conventional landing gear equipped, wire braced parasol wing aircraft. Aeronautical designer Ivan Diggs designed a new 30 ft wing for the Longster. The wire bracing is supported by a central cabane post located over a above-wing fuel tank. The fuselage is steel tubing. The design also features pinned and brazed gusset joints as opposed to conventionally welded joint clusters.
An example of a Longster is on display at the Western Antique Aeroplane & Automobile Museum.