Narrative:

On base to a visual approach to runway into airport; we were configuring for landing. As the PF commanded flaps 15; we noticed the left flap was indicating 3 and the right 5. We requested a delay vector with tower and were directed to contact approach and started the trailing flap asymmetry checklist. After the completion of the checklist; prior to the deferred items; we positioned the flap lever to the closest setting to the less extended flap; flaps 2. At some point after positioning the flap lever to 2 the flaps deployed symmetrically to 5. The captain and I had a discussion about whether to run the trailing edge flap disagree checklist and decided against it since we had adequate landing performance; a symmetric flap condition; and didn't want to risk another asymmetry. The captain gave me control of the aircraft and we started turning back for the approach while he made a couple pas to the passengers and informed the flight attendants. We also [advised ATC] to have equipment standing by in case of hot brakes or any unforeseen problems. The landing was uneventful but the target speed was 161 knots. We cleared the runway; talked to the passengers; and taxied to the gate leaving the flap lever at the 2 position. As we exited the runway; we noticed the flaps had retracted to the 2 position symmetrically. We also noticed we now had a pseu light. Once at the gate we wrote the defect up and waited for maintenance to arrive.

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Original NASA ASRS Text

Title: With flaps commanded at 15; the flap indicator showed left flap at 3 and right flap at 5. There was no control issue so during approach; positioned flap lever to 2; the flaps deployed to 5. After landing; the flap lever was left at 2 and the flaps retracted to 2 symmetrically.

Narrative: On base to a visual approach to Runway into airport; we were configuring for landing. As the PF commanded flaps 15; we noticed the left flap was indicating 3 and the right 5. We requested a delay vector with Tower and were directed to contact Approach and started the Trailing Flap Asymmetry Checklist. After the completion of the checklist; prior to the deferred items; we positioned the flap lever to the closest setting to the less extended flap; flaps 2. At some point after positioning the flap lever to 2 the flaps deployed symmetrically to 5. The Captain and I had a discussion about whether to run the Trailing Edge Flap Disagree Checklist and decided against it since we had adequate landing performance; a symmetric flap condition; and didn't want to risk another asymmetry. The Captain gave me control of the aircraft and we started turning back for the approach while he made a couple PAs to the Passengers and informed the Flight Attendants. We also [advised ATC] to have equipment standing by in case of hot brakes or any unforeseen problems. The landing was uneventful but the target speed was 161 knots. We cleared the runway; talked to the Passengers; and taxied to the gate leaving the flap lever at the 2 position. As we exited the runway; we noticed the flaps had retracted to the 2 position symmetrically. We also noticed we now had a PSEU light. Once at the gate we wrote the defect up and waited for Maintenance to arrive.

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.