Incident Description
The airplane landed and, according to the pilot, he may have "possibly inadvertently hit the gear handle." Subsequently, the nose gear retracted and the airplane skidded down the centerline before drifting off the left side and sliding another 300 feet. The left main landing gear then retracted.
Damage Assessment
In addition to a broken left wing tip fairing, scraped landing gear doors, a crushed exhaust manifold, and a bent propeller, there was structural damage to the nose wheel tunnel.
Manufacturer's Analysis
According to the manufacturer, the airplane was equipped with a "squat switch" that senses weight-on-wheels and prevents inadvertent landing gear retraction. The spokesman said there were several reasons why the landing gear may have retracted: a defective squat switch, an over-inflated nose gear strut (that would cause the electrical contacts of the squat switch to separate), misrigging of the squat switch, or the airplane may have bounced, allowing the electrical contacts to separate.
Post-Incident Testing
According to the repair facility that retrieved the airplane, the squat switch was functionally tested and it operated satisfactorily.