Landing Gear Retraction During Takeoff Leads to Runway Excursion (N2126K)

Accident Description

A single-engine retractable gear airplane experienced a landing gear retraction during takeoff, resulting in a runway excursion. After takeoff, the pilot engaged the override function of the landing gear's auto extension system. Prior to arrival at the destination airport, the pilot disengaged the override. During the approach to land, the pilot performed the prelanding checklist and observed three green lights indicating gear extension. Upon departure, the pilot accelerated to a higher than normal speed due to perceived residual wake turbulence. The airplane lifted off and the landing gear began to retract. The airplane settled onto the runway and slid off into the grass. The gear selector switch was found in the up position. The landing gear auto extension system functions on the basis of lower airspeeds and reduced power. The pilot could not recall if he had placed the gear selector switch in the down position during his arrival at the accident airport.