Narrative:

Upon gate arrival my first officer was doing his walk around before our next flight and he brought to my attention damage to the tail of the aircraft. I then went out to inspect and saw damage to the drain line for the APU. I called maintenance to have them come out and inspect; and also check if this was previously reported. While waiting for them to arrive I went back out side with the lavatory service truck gone I also observed damage to the aft water drain. The combined damage led me to believe the tail of the aircraft struck the ground. My thoughts went back to an earlier flight; in the process of landing during touchdown and roll out the nose was a little higher than normal; but at the time I did not think it was high enough to strike the tail; nor did we feel anything.

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Original NASA ASRS Text

Title: EMB175 flight crew discovered tail damage during post flight which presumably occurred during one of their flights; but went unsuspected and undetected. Aircraft is taken out of service.

Narrative: Upon gate arrival my First Officer was doing his walk around before our next flight and he brought to my attention damage to the tail of the aircraft. I then went out to inspect and saw damage to the drain line for the APU. I called maintenance to have them come out and inspect; and also check if this was previously reported. While waiting for them to arrive I went back out side with the lavatory service truck gone I also observed damage to the aft water drain. The combined damage led me to believe the tail of the aircraft struck the ground. My thoughts went back to an earlier flight; in the process of landing during touchdown and roll out the nose was a little higher than normal; but at the time I did not think it was high enough to strike the tail; nor did we feel anything.

Data retrieved from NASA's ASRS site as of April 2012 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.