Narrative:

During cruise flight; the right hand cargo door inadvertently left the aircraft. The aircraft experienced a 'thump' with no other indications. The aircraft landed safely as scheduled. Upon post-flight; it was discovered that there was damage to the main rotor blade. [There were] no injuries to passenger or crew.

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Original NASA ASRS Text

Title: UH-1H Captain reported the right side cargo door departed the aircraft in cruise flight.

Narrative: During cruise flight; the right hand cargo door inadvertently left the aircraft. The aircraft experienced a 'thump' with no other indications. The aircraft landed safely as scheduled. Upon post-flight; it was discovered that there was damage to the main rotor blade. [There were] no injuries to passenger or crew.

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.