Narrative:

During climb out en-route the crew heard a very loud noise. The pax confirmed the noise & the captain traveled to the aft lav to confirm the noise & the aft lav floor was heavily vibrating. The crew slowed the aircraft down & the noise decreased & thus decided to return to [the departure airport]. Upon shut down noticed the panel between the gear on the belly in front of the aft equipment access door missing.

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Original NASA ASRS Text

Title: The flight crew of a Bombardier G5000 reported that during climb a panel on the bottom of the fuselage fell off.

Narrative: During climb out en-route the crew heard a very loud noise. The pax confirmed the noise & the captain traveled to the aft lav to confirm the noise & the aft lav floor was heavily vibrating. The crew slowed the aircraft down & the noise decreased & thus decided to return to [the departure airport]. Upon shut down noticed the panel between the gear on the belly in front of the aft equipment access door missing.

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.