Narrative:

After approximately 3 hours into the flight we noticed that the [remaining] fuel was decreasing and that our ETA had increased by approximately 20 minutes. We attributed this to the fact that the winds were more on the nose than was forecast. The [remaining] fuel continued to decrease slowly. After a few minutes we noticed a 200 pound imbalance between the wing tanks. I rebalanced the fuel and then set the timer to monitor the situation. Within 10 minutes an almost 300 pound imbalance had established. After consulting the QRH we decided that we probably had a fuel leak. We sent a message to maintenance control and dispatch and informed ATC that we needed to divert to [an airport] which was only about 40 miles behind us. ATC immediately descended us and turned us directly to [the airport] for a straight in ILS. At this point things got busy. I told the flight attendants what was going on and made a PA to the passengers. We ran the approach descent checklist; briefed the approach and did the approach checklist. We discussed shutting down the #2 engine as described in the QRH but we agreed that would delay our arrival while we did the procedure in the QRH. At this point we were only about 10 miles from the airport and had about 5500 pounds of fuel. We made an uneventful landing and clearing the runway we shut down #2 engine. After arrival at the gate maintenance confirmed that we had a fuel leak in #2 engine.

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Original NASA ASRS Text

Title: B737 flight crew reported they noticed on a transcontinental flight they were developing a fuel imbalance that looked like a fuel leak. They diverted to a nearby airport where a fuel leak in #2 engine was confirmed.

Narrative: After approximately 3 hours into the flight we noticed that the [remaining] fuel was decreasing and that our ETA had increased by approximately 20 minutes. We attributed this to the fact that the winds were more on the nose than was forecast. The [remaining] fuel continued to decrease slowly. After a few minutes we noticed a 200 pound imbalance between the wing tanks. I rebalanced the fuel and then set the timer to monitor the situation. Within 10 minutes an almost 300 pound imbalance had established. After consulting the QRH we decided that we probably had a fuel leak. We sent a message to Maintenance Control and Dispatch and informed ATC that we needed to divert to [an airport] which was only about 40 miles behind us. ATC immediately descended us and turned us directly to [the airport] for a straight in ILS. At this point things got busy. I told the Flight Attendants what was going on and made a PA to the passengers. We ran the approach descent checklist; briefed the approach and did the approach checklist. We discussed shutting down the #2 engine as described in the QRH but we agreed that would delay our arrival while we did the procedure in the QRH. At this point we were only about 10 miles from the airport and had about 5500 pounds of fuel. We made an uneventful landing and clearing the runway we shut down #2 engine. After arrival at the gate maintenance confirmed that we had a fuel leak in #2 engine.

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.