Narrative:

Upon reaching FL230; the fuel in tank #3 was about 1500 pounds out of balance. We opened the #2 and #3 xfeed valves with #3 boost pumps on and #1 xfeed valve closed with its boost pumps on for a few mins. #3 tank didn't go down like it should have; also tank #2 with boost pumps off continued to go down. Then we checked all lights and circuit breakers. Then we opened #1 xfeed valve and shut off boost pumps to tank #1. This also didn't seem to burn much fuel out of tank #3 but tanks #1 and #2 continued to go down in this confign. Trying to keep fuel balanced as good as we could; burned out of tank #2 with 2 boost pumps to feed engine #1 and engine #2. Tank #1 no boost pumps on though maybe a bad fuel gauge on tank #3 but we did fuel checks and the burn was always close to flight plan burn. There is no real communication procedure for this problem. We landed with 20.7 total. Tank #1 had about 4.2; tank #3 had about 6.0; and tank #2 had about 10.5. The first officer said he had seen something like this before; when the fuel panel switches were not closed properly underneath the wing. After landing we sent the mechanic to check the fuel panel. He said the #3 fuel switch was not closed. This switch appeared to be the problem.

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Original NASA ASRS Text

Title: A B727-200 CREW RPT WHEN LEVELING OFF AT FL230 #3 TANK INDICATION WAS 1500 LBS OUT OF BAL. ON ARR AT DEST; FOUND #3 FUELING VALVE SWITCH IN OPEN POS ON FUELING PANEL.

Narrative: UPON REACHING FL230; THE FUEL IN TANK #3 WAS ABOUT 1500 LBS OUT OF BAL. WE OPENED THE #2 AND #3 XFEED VALVES WITH #3 BOOST PUMPS ON AND #1 XFEED VALVE CLOSED WITH ITS BOOST PUMPS ON FOR A FEW MINS. #3 TANK DIDN'T GO DOWN LIKE IT SHOULD HAVE; ALSO TANK #2 WITH BOOST PUMPS OFF CONTINUED TO GO DOWN. THEN WE CHKED ALL LIGHTS AND CIRCUIT BREAKERS. THEN WE OPENED #1 XFEED VALVE AND SHUT OFF BOOST PUMPS TO TANK #1. THIS ALSO DIDN'T SEEM TO BURN MUCH FUEL OUT OF TANK #3 BUT TANKS #1 AND #2 CONTINUED TO GO DOWN IN THIS CONFIGN. TRYING TO KEEP FUEL BALANCED AS GOOD AS WE COULD; BURNED OUT OF TANK #2 WITH 2 BOOST PUMPS TO FEED ENG #1 AND ENG #2. TANK #1 NO BOOST PUMPS ON THOUGH MAYBE A BAD FUEL GAUGE ON TANK #3 BUT WE DID FUEL CHKS AND THE BURN WAS ALWAYS CLOSE TO FLT PLAN BURN. THERE IS NO REAL COM PROC FOR THIS PROB. WE LANDED WITH 20.7 TOTAL. TANK #1 HAD ABOUT 4.2; TANK #3 HAD ABOUT 6.0; AND TANK #2 HAD ABOUT 10.5. THE FO SAID HE HAD SEEN SOMETHING LIKE THIS BEFORE; WHEN THE FUEL PANEL SWITCHES WERE NOT CLOSED PROPERLY UNDERNEATH THE WING. AFTER LNDG WE SENT THE MECH TO CHK THE FUEL PANEL. HE SAID THE #3 FUEL SWITCH WAS NOT CLOSED. THIS SWITCH APPEARED TO BE THE PROB.

Data retrieved from NASA's ASRS site as of January 2009 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.