Narrative:

During climbout on the previous flight; around 10;000 to 15;000 feet several loud bangs were heard in the cockpit. It sounded as if the aft wall of the cockpit was shifting. This was loud enough to startle both me and my first officer. This happened again on the flight back to ZZZ around the same altitude. I have never heard a noise like this before in over 6000+ hours in this airplane. I would describe it as metal being hit with the nose of the plastic cockpit paneling moving as well. I thought I heard the jump seat move as well. The air was smooth the whole time this was happening and the flight attendants did not see anyone in the forward lavatory at the time nor were they banging on the galley or cockpit door. This sounded as if there was a structural problem with the airplane and this needs to be corrected on this airplane.

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Original NASA ASRS Text

Title: EMB-170 Captain reported a series of loud bangs near the aft wall of the cockpit.

Narrative: During climbout on the previous flight; around 10;000 to 15;000 feet several loud bangs were heard in the cockpit. It sounded as if the aft wall of the cockpit was shifting. This was loud enough to startle both me and my First Officer. This happened again on the flight back to ZZZ around the same altitude. I have never heard a noise like this before in over 6000+ hours in this airplane. I would describe it as metal being hit with the nose of the plastic cockpit paneling moving as well. I thought I heard the jump seat move as well. The air was smooth the whole time this was happening and the flight attendants did not see anyone in the forward lavatory at the time nor were they banging on the galley or cockpit door. This sounded as if there was a structural problem with the airplane and this needs to be corrected on this airplane.

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.