Narrative:

I was in route on my 2nd leg of a 4 leg round robin trip in southern california. On my 2nd leg; I had just obtained ATIS and contacted tower before entering class D. I was approximately 11 SM due east from [the airport] at 2;600 MSL descending on a straight line. I had just informed tower that I had information alpha from ATIS and I was inbound when I felt a small quick vibration and what felt like a depressurization and loud pop and blowout with tremendous wind turbulence inside the cockpit. I immediately look over my shoulder and noticed the rear canopy door was either open and/or missing; but I wasn't sure yet because of the initial shock. I immediately informed tower of my status and they began to clear the pattern for my arrival. The tower asked if I need assistance or want [priority handling]. I once again looked over my left shoulder (several more times to confirm) and noticed the canopy door was completely gone and I informed them that I still had control of the aircraft; but would slow down to eliminate the tremendous internal vibration and wind turbulence and wouldn't be [needing priority handling] at this time. I continued on my approach; slowing down to about 80-85 KTS from 120-125 KTS; cautiously and landed safely without further incident. The aircraft is a rental that I've flown personally several times over the course of [many] years.

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Original NASA ASRS Text

Title: The Pilot of a Diamond Star DA40 Reported the rear canopy door came completely off during approach.

Narrative: I was in route on my 2nd leg of a 4 leg round robin trip in southern California. On my 2nd leg; I had just obtained ATIS and contacted Tower before entering class D. I was approximately 11 SM due east from [the airport] at 2;600 MSL descending on a straight line. I had just informed Tower that I had information ALPHA from ATIS and I was inbound when I felt a small quick vibration and what felt like a depressurization and loud pop and blowout with tremendous wind turbulence inside the cockpit. I immediately look over my shoulder and noticed the rear canopy door was either open and/or missing; but I wasn't sure yet because of the initial shock. I immediately informed Tower of my status and they began to clear the pattern for my arrival. The Tower asked if I need assistance or want [priority handling]. I once again looked over my left shoulder (several more times to confirm) and noticed the canopy door was completely gone and I informed them that I still had control of the aircraft; but would slow down to eliminate the tremendous internal vibration and wind turbulence and wouldn't be [needing priority handling] at this time. I continued on my approach; slowing down to about 80-85 KTS from 120-125 KTS; cautiously and landed safely without further incident. The aircraft is a rental that I've flown personally several times over the course of [many] years.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.