Baron 58/58TC
Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Private
Flight Crew Last 90 Days 33; Flight Crew Total 769; Flight Crew Type 86
Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural FAR; Deviation / Discrepancy - Procedural Published Material / Policy; Flight Deck / Cabin / Aircraft Event Other / Unknown
Flight Crew Returned To Departure Airport; Flight Crew Overcame Equipment Problem
Procedure; Aircraft
After acceptance an IFR clearance from ZZZ to ZZZ1; myself; as PIC (Pilot in Command); and a passenger; in the co-pilot seat; departed Runway XX (ZZZ). At 1;000 feet AGL; I checked in with Departure on the climb out. All was normal until we realized the cockpit door was not fully closed and secured. The latch on the top of the door appeared to have not fully engaged. At approximately 3;200 feet MSL; the door popped open and I decided to immediately return to ZZZ. I informed Departure of my intentions to return to ZZZ. Due to wind noise in the cockpit; I could only partially hear ATC's response. I entered a right downwind for Runway XX and informed the Tower of my location and intentions. The Tower cleared me to land and I proceeded to a normal landing on Runway XX. The taxi back to the FBO was normal. Within 30 minutes we were airborne on an amended IFR flight plan; with the door properly closed and secured.
Baron 58 Pilot reported failing to secure the crew door correctly and after takeoff; it opened requiring an Air Turn Back to re secure the door and depart again.