Narrative:

After we had done the safety briefing; we were in the back galley. The aircraft was in taxi out mode. The other flight attendant noticed that the safety strap at the L2 door was stuck in the door. I tried to pull it back in; but it would not budge. I saw some light coming through from where the strap was. I called the flight deck; apologized for interrupting; and asked if they were showing any indications of the integrity of the seal being breeched. He said everything looked fine. I told him about the strap. I said that if he could stop the aircraft; I could quickly crack the door and bring the strap back in. He said it wasn't as easy as that because the aircraft was already pressurized. I then asked him what the ramifications could be if we left it alone. He said that it might cause a squealing sound on climb but should eventually go away when we leveled off. So; I said as long as there weren't any warning bells; and he was comfortable with leaving it; then I would leave it alone. I also said that I would contact him if anything happened. As soon as we took off; the door started squealing; and it actually got louder the higher we went. It could be heard full force all the way up to the divider. It was like a horn being blown. I waited until 10;000 to see if it would go away; but it didn't. I called the pilots; and they could hear it over the intercom without me telling them. He suggested putting a wet rag on it. That didn't do anything. No one was complaining about any physical reactions; except the other flight attendant was getting a headache. The noise was just so obnoxiously loud that it wasn't right to put the passengers through it. So; the captain returned to the departure airport. On the ground; a mechanic from one of the smaller airlines; came and checked out the door seal; said it was fine; we took on more gas; and we left. Maybe emphasizing something like 'strap check' in the whole door closure routine.

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Original NASA ASRS Text

Title: A B737's L2 door safety strap was trapped in the door seal after it was closed but the crew decided to depart only to return to the departure airport because of the excessively loud squeal.

Narrative: After we had done the safety briefing; we were in the back galley. The aircraft was in taxi out mode. The other Flight Attendant noticed that the safety strap at the L2 door was stuck in the door. I tried to pull it back in; but it would not budge. I saw some light coming through from where the strap was. I called the flight deck; apologized for interrupting; and asked if they were showing any indications of the integrity of the seal being breeched. He said everything looked fine. I told him about the strap. I said that if he could stop the aircraft; I could quickly crack the door and bring the strap back in. He said it wasn't as easy as that because the aircraft was already pressurized. I then asked him what the ramifications could be if we left it alone. He said that it might cause a squealing sound on climb but should eventually go away when we leveled off. So; I said as long as there weren't any warning bells; and he was comfortable with leaving it; then I would leave it alone. I also said that I would contact him if anything happened. As soon as we took off; the door started squealing; and it actually got louder the higher we went. It could be heard full force all the way up to the divider. It was like a horn being blown. I waited until 10;000 to see if it would go away; but it didn't. I called the pilots; and they could hear it over the intercom without me telling them. He suggested putting a wet rag on it. That didn't do anything. No one was complaining about any physical reactions; except the other Flight Attendant was getting a headache. The noise was just so obnoxiously loud that it wasn't right to put the passengers through it. So; the Captain returned to the departure airport. On the ground; a mechanic from one of the smaller airlines; came and checked out the door seal; said it was fine; we took on more gas; and we left. Maybe emphasizing something like 'strap check' in the whole door closure routine.

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.