Lancair Columbia
Flight Crew Multiengine; Flight Crew Flight Instructor; Flight Crew Commercial; Flight Crew Instrument
Flight Crew Last 90 Days 53; Flight Crew Total 3320; Flight Crew Type 50
Other / Unknown
Aircraft Equipment Problem Critical; Inflight Event / Encounter Other / Unknown
Aircraft Aircraft Damaged; Flight Crew Returned To Departure Airport; Flight Crew Requested ATC Assistance / Clarification; Flight Crew Landed in Emergency Condition
Aircraft; Human Factors
I was giving a demonstration flight to a person who had never flown a Columbia 400. The person was in the left seat; I was in the right. I showed him how to latch the door; and during the taxi and run-up I never saw a 'door open' annunciation on the panel; which should show up when any of the aircraft's doors are not latched. The person said his door was closed and latched; and he even tugged on it for security. I should have visually checked that the door was secure. We took off and were climbing out about a mile or so from the departure end of the runway; heading west; when suddenly the left door opened and completely detached from the airplane. I took control immediately and told the Departure Controller that we lost the door and needed to return to the airport with priority. The Controller switched me back to Tower and we landed uneventfully. I later went up in another airplane with a coworker and searched the area briefly for the door; and then drove in the area looking for it as well; but was unsuccessful.
Columbia 400 pilot reported that a cabin door detached from the aircraft on takeoff; resulting in a return to land.