Date: 202011
Local time of day: 0601-1200
Location: ZZZ.Airport, US
Flight conditions: VMC
Weather elements / visibility: 10
Light: Daylight
Aircraft: Cessna 150
Operator: Personal
Operating under: Part 91
Flight plan: VFR
Mission: Personal
Flight phase: Parked; Cruise
Aircraft component: Fuselage Door Frame
Component problem: Malfunctioning; Improperly Operated
Reporter organization: Personal
Reporter function: Single Pilot; Pilot Flying
Reporter qualification: Flight Crew Private
Human factors: Communication Breakdown; Training / Qualification
Anomaly: Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Maintenance; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural FAR; Flight Deck / Cabin / Aircraft Event Other / Unknown; Inflight Event / Encounter Other / Unknown
Detector: Person Flight Crew
Result: Aircraft Aircraft Damaged; Flight Crew Took Evasive Action; Flight Crew Returned To Departure Airport; General Maintenance Action; General Flight Cancelled / Delayed
Contributing factors: Aircraft; Human Factors; Procedure
Primary problem: Aircraft

Narrative: The planned flight was VFR from ZZZ to ZZZ1 via ZZZ2 and ZZZ3 at XA:00 on November [date] 2020 in Aircraft X (Cessna 150) rented from Company. I was PIC; Person Y was the only passenger. We had previously flown Aircraft X on July [date] 2020 from ZZZ; ZZZ4; ZZZ3 and had noted that the passenger door was not closing properly -- a small gap in the upper-left corner of the window frame allowed wind to enter the cabin. The owner of the plane investigated the issue then and found that the upper window frame was bent. I assumed that the issue was fixed by an A&P mechanic after the investigation. The plane has been regularly flown by other pilots since July.On November [date] 2020; I noticed no irregularities during pre-flight. During run-up; I noticed that the gap in the passenger door was still present and was a bit bigger than I remembered it from July. I thought that the slight wind in the cabin would be unpleasant but not otherwise an issue and continued with the flight. During the take-off roll just after rotation; the passenger door swung open. Once we were stabilized on the downwind; I shut the door and reassured my passenger. However the passenger door swung open again -- the wind through the upper-left gap torqued the entire door outward and that overpowered the door latch. So I requested landing clearance from ZZZ Tower and executed a precautionary landing without any incident. I taxied back to parking; shut off the engine and investigated the passenger door. The upper window frame was flexing slightly and could be bent to snap into the correct position. I pushed the frame into the correct position; verified that the frame was now snug against all the door frame inserts and that no wind was leaking into the cabin.I took off from ZZZ around XB:00 and noted no issues this time. As we were transitioning ZZZ3 Class D airspace; my passenger noted that she heard some sound from her door. I verified that the gap in the window frame was not present and that the door was shut properly. Shortly after we flew through the Class D; my passenger also reported that she could feel cold air from near the lower-right part of her door. As we flew past the marina; the door again swung open. This time the door shook violently which caused the window also to be flung open. I requested landing clearance from ZZZ3 was given priority and then I clarified my situation. I noted that reducing the throttle helped remove the violent door shaking. I reached over to shut the door; then pulled the upper window frame back into the door inserts and then closed the window. The ATC alerted me with a low altitude warning; so I decided to ignore the door and climb 300 ft. to intercept the glide slope and fly the plane first. As I increased RPM; the door again flung open. The door was twisting and wobbling around the hinge like a sheet of paper with the hinge as a paper-clip; and either wind or resonant frequency was increasing the severity of the wobbles. My passenger held the door to dampen its shaking. The landing at ZZZ3 was without any incident; and I taxied to a maintenance shop on the field. An A&P mechanic diagnosed that the passenger door needs to be replaced entirely and that the plane was not airworthy. We drove back to ZZZ after ensuring that the owner of Aircraft X knew what had happened and where to find the plane's key.In follow-up communication with the owner; I do not believe that the plane door was inspected and fixed by an A&P mechanic in July. The owner mentioned that he adjusted the door latches and attempted to bend the window frame back into place. This 'fix' ensured that the 'door shut properly 90% of the time'. He mentioned that he drove up to ZZZ3 with a spare C150 door and replaced it -- I do not know that he is qualified to make such repairs. His name does not show up in the airmen registry as holding an A&P license. The owner also mentioned that he was checking the door occasionally and that it had clearly worsened in the lastcouple of weeks and that there is no strength left in the window frame.Based on our conversations; I believe that the owner fixed the discrepancies that pilots reported using methods that are not by the book.(1) Normalization of deviance. I should have canceled the flight after landing at ZZZ after the initial trouble with the door.(2) Normalization of deviance. Owner should have replaced the door in July; rather than waiting for the door condition to get worse and create an [issue].(3) Crew management. I should have briefed my passenger during/after the [event]. She thankfully did all the right things (e.g. dampen the door vibrations) purely on instinct.(4) Aviate & Declare. I did not use 'emergency' or 'mayday' in my communications; despite that; the ATC at ZZZ and ZZZ3 both realized that something was up and gave me priority. Kudos to them. When diverting to ZZZ3; I flew very close to the prohibited airspace near marina to minimize my flight path to the runway.(5) Pre-flight Airworthiness Check. I should have insisted on viewing the maintenance records of the airplane to verify that my previous squawks were satisfactorily addressed.




Synopsis: C150 pilot reported multiple issues with the passenger door opening in flight on a rental plane.