Narrative:

The original airplane [for this trip] had a maintenance issue and was taken to the hangar. They then did an airplane swap to [this] aircraft. This airplane had previously been written up for a banging noise at cruise and was just returning from a maintenance flight. The flight crew and maintenance personnel conducting the maintenance flight didn't hear any banging and signed off the airplane to go back into service. We preflighted the airplane; loaded the passengers; pushed from the gate; and took off. Then about 25-30 minutes into the flight and climbing through FL220 the captain heard the first bang sound. A minute or so later I heard the bang for the first time as we were still in climb. As we neared closer to our cruising altitude the captain and I heard several more bangs and concluded that they were coming from somewhere around the nose wheel gear bay or perhaps the nose gear doors. We then discussed whether or not to continue the flight to [our filed destination] and at this time I took temporary control of the flight controls so the captain could ACARS message maintenance control and dispatch. While waiting for a reply he called the flight attendant to tell her we may be diverting. She then said she had heard the banging as far back as the galley. Once we leveled in cruise the banging was more pronounced and frequent. Between the captain and dispatch the decision was made to air return to the departure airport and the captain asked for our departure point to be placed on the flight release. We then coordinated with center to return. We did not declare an emergency and informed ATC it was for the banging noise. After all the time coordinating with dispatch and ATC we finally turned back north. On our way back to we contacted operations and prepared the airplane for an air return. I also looked up QRH procedures just in case the nose wheel would not come down. Finally we landed uneventfully.the only threat to the aircraft was the banging noise and the fact that we couldn't exactly identify what was causing it. I thought as a flight crew we worked very well to mitigate the chance of any other threats; errors; and undesired aircraft states to safely return to the airport. The company and maintenance personnel need to better simulate conditions from maintenance write-ups in order to return airplanes to services. If multiple pilots have said they heard banging noises up at cruising altitudes then a turn in the pattern is not simulating the same conditions of the original right up. In my opinion the cost of a proper maintenance check out was probably a factor as well and isn't always good safety policy.

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Original NASA ASRS Text

Title: An EMB-145 returned to the departure airport after the pilots and Flight Attendant heard a banging sound in the aircraft's forward section while at cruise. A previous maintenance test flight for the banging was negative.

Narrative: The original airplane [for this trip] had a maintenance issue and was taken to the hangar. They then did an airplane swap to [this] aircraft. This airplane had previously been written up for a banging noise at cruise and was just returning from a maintenance flight. The flight crew and maintenance personnel conducting the maintenance flight didn't hear any banging and signed off the airplane to go back into service. We preflighted the airplane; loaded the passengers; pushed from the gate; and took off. Then about 25-30 minutes into the flight and climbing through FL220 the Captain heard the first bang sound. A minute or so later I heard the bang for the first time as we were still in climb. As we neared closer to our cruising altitude the Captain and I heard several more bangs and concluded that they were coming from somewhere around the nose wheel gear bay or perhaps the nose gear doors. We then discussed whether or not to continue the flight to [our filed destination] and at this time I took temporary control of the flight controls so the Captain could ACARS message Maintenance Control and Dispatch. While waiting for a reply he called the Flight Attendant to tell her we may be diverting. She then said she had heard the banging as far back as the galley. Once we leveled in cruise the banging was more pronounced and frequent. Between the Captain and Dispatch the decision was made to air return to the departure airport and the Captain asked for our departure point to be placed on the flight release. We then coordinated with Center to return. We did not declare an emergency and informed ATC it was for the banging noise. After all the time coordinating with Dispatch and ATC we finally turned back north. On our way back to we contacted Operations and prepared the airplane for an air return. I also looked up QRH procedures just in case the nose wheel would not come down. Finally we landed uneventfully.The only threat to the aircraft was the banging noise and the fact that we couldn't exactly identify what was causing it. I thought as a flight crew we worked very well to mitigate the chance of any other threats; errors; and undesired aircraft states to safely return to the airport. The company and maintenance personnel need to better simulate conditions from maintenance write-ups in order to return airplanes to services. If multiple pilots have said they heard banging noises up at cruising altitudes then a turn in the pattern is not simulating the same conditions of the original right up. In my opinion the cost of a proper maintenance check out was probably a factor as well and isn't always good safety policy.

Data retrieved from NASA's ASRS site as of July 2013 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.