Narrative:

On rotation a thunk was heard followed by the intermittent indication of rudder hydraulic system inoperative EICAS message. Flew the plane up to 5;000 feet [and] asked for a heading. EICAS message was now constant. Ran the QRH. Pressures and quantity were normal and hydraulic electric pumps were off. Decided to return to [departure airport]. Checked landing weight and informed ATC of our plan to return. First officer (first officer) was off informing ops; company; flight attendant and passengers. Normal approach and landing.

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Original NASA ASRS Text

Title: EMB-145LR Captain reported returning to departure airport after noting the EICAS message 'Rudder Hyd Sys Inop'.

Narrative: On rotation a thunk was heard followed by the intermittent indication of Rudder HYD SYS INOP EICAS message. Flew the plane up to 5;000 feet [and] asked for a heading. EICAS message was now constant. Ran the QRH. Pressures and quantity were normal and hydraulic electric pumps were off. Decided to return to [departure airport]. Checked landing weight and informed ATC of our plan to return. First Officer (FO) was off informing ops; company; flight attendant and passengers. Normal approach and landing.

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.