Narrative:

Flying a scheduled cargo flight from cvg to phx, then phx to lax. This particular B727 had 4 dmi's on which 2 involved the fuel system: 1) #1 fuel quantity gauge inoperative. 2) #1 xfeed inoperative open. After approximately 2 hours, I calculated the fuel score of approximately 38000 pounds for my mid-point report. The captain wanted to compare my figures with the flight plan and came up with an 8000 pound difference. The aircraft, on autoplt, appeared to be flying out of trim, ie, right wing down and left rudder. Departing cvg, #1 fuel quantity gauge was inoperative (but showed 4300 pounds). It was fairly close to ama airport when the gauge started to steadily decrease. As a crew, we deduced that the gauge may be reflecting the 'correct' figure, and that the fuel had been burning out of tank #1 since takeoff. We performed a precautionary landing at ama. Contract maintenance at ama found the xfeed valve wired closed. Fortunately, I left the boost pumps 'on' in task #1. The B727-200 has overriding #2 boost pumps which prevented a flameout on climb out and at cruise. Also, by discovering the predicament early, the engine did not flame out due to fuel starvation, and placed us in a position of a heavy right wing and a #1 engine out. And, with the fuel quantity as low as it was, noticed the B hydraulic pump did not overheat to compound the problem. Callback conversation with reporter revealed the following information: normally, when the fuel load is more than 36000 pounds, there is more fuel in #2 tank than in tanks #1 or #3. The plan, early in the flight, is to feed all 3 engines from the #2 tank until all 3 tanks have the same fuel remaining. To do this, all 3 xfeeds are usually opened and, if the boost pumps in #2 are on, they will overpwr the other boost pumps if they are on and feed all 3 engines from the #2 tank. The mechanics said that the #1 xfeed valve was wired open and wrote it up in the logbook as such. Actually, the #1 xfeed had been wired closed. Therefore, when the #2 boost pumps were turned on, engines #2 and #3 were fed by the #2 tank but the #1 engine could get no fuel from the #2 tank through the xfeed valve and drew fuel from the #1 tank. The results: #1 tank was burning fuel and #3 was not. This caused the fuel imbal. Because the #1 fuel quantity gauge was also inoperative, this was not apparent to the flight crew. Further, if the #1 engine had been allowed to burn all the fuel in the #1 tank, there would have been no way to feed fuel to that engine and it would have flamed out. The en route stop at ama, or some other alternate, was their only recourse.

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Original NASA ASRS Text

Title: B727-200 FREIGHTER IS UNABLE TO XFEED FUEL TO THE #1 ENG AND HAS TO DIVERT TO AMA FOR MAINT AND FUEL.

Narrative: FLYING A SCHEDULED CARGO FLT FROM CVG TO PHX, THEN PHX TO LAX. THIS PARTICULAR B727 HAD 4 DMI'S ON WHICH 2 INVOLVED THE FUEL SYS: 1) #1 FUEL QUANTITY GAUGE INOP. 2) #1 XFEED INOP OPEN. AFTER APPROX 2 HRS, I CALCULATED THE FUEL SCORE OF APPROX 38000 LBS FOR MY MID-POINT RPT. THE CAPT WANTED TO COMPARE MY FIGURES WITH THE FLT PLAN AND CAME UP WITH AN 8000 LB DIFFERENCE. THE ACFT, ON AUTOPLT, APPEARED TO BE FLYING OUT OF TRIM, IE, R WING DOWN AND L RUDDER. DEPARTING CVG, #1 FUEL QUANTITY GAUGE WAS INOP (BUT SHOWED 4300 LBS). IT WAS FAIRLY CLOSE TO AMA ARPT WHEN THE GAUGE STARTED TO STEADILY DECREASE. AS A CREW, WE DEDUCED THAT THE GAUGE MAY BE REFLECTING THE 'CORRECT' FIGURE, AND THAT THE FUEL HAD BEEN BURNING OUT OF TANK #1 SINCE TKOF. WE PERFORMED A PRECAUTIONARY LNDG AT AMA. CONTRACT MAINT AT AMA FOUND THE XFEED VALVE WIRED CLOSED. FORTUNATELY, I LEFT THE BOOST PUMPS 'ON' IN TASK #1. THE B727-200 HAS OVERRIDING #2 BOOST PUMPS WHICH PREVENTED A FLAMEOUT ON CLB OUT AND AT CRUISE. ALSO, BY DISCOVERING THE PREDICAMENT EARLY, THE ENG DID NOT FLAME OUT DUE TO FUEL STARVATION, AND PLACED US IN A POS OF A HVY R WING AND A #1 ENG OUT. AND, WITH THE FUEL QUANTITY AS LOW AS IT WAS, NOTICED THE B HYD PUMP DID NOT OVERHEAT TO COMPOUND THE PROB. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: NORMALLY, WHEN THE FUEL LOAD IS MORE THAN 36000 LBS, THERE IS MORE FUEL IN #2 TANK THAN IN TANKS #1 OR #3. THE PLAN, EARLY IN THE FLT, IS TO FEED ALL 3 ENGS FROM THE #2 TANK UNTIL ALL 3 TANKS HAVE THE SAME FUEL REMAINING. TO DO THIS, ALL 3 XFEEDS ARE USUALLY OPENED AND, IF THE BOOST PUMPS IN #2 ARE ON, THEY WILL OVERPWR THE OTHER BOOST PUMPS IF THEY ARE ON AND FEED ALL 3 ENGS FROM THE #2 TANK. THE MECHS SAID THAT THE #1 XFEED VALVE WAS WIRED OPEN AND WROTE IT UP IN THE LOGBOOK AS SUCH. ACTUALLY, THE #1 XFEED HAD BEEN WIRED CLOSED. THEREFORE, WHEN THE #2 BOOST PUMPS WERE TURNED ON, ENGS #2 AND #3 WERE FED BY THE #2 TANK BUT THE #1 ENG COULD GET NO FUEL FROM THE #2 TANK THROUGH THE XFEED VALVE AND DREW FUEL FROM THE #1 TANK. THE RESULTS: #1 TANK WAS BURNING FUEL AND #3 WAS NOT. THIS CAUSED THE FUEL IMBAL. BECAUSE THE #1 FUEL QUANTITY GAUGE WAS ALSO INOP, THIS WAS NOT APPARENT TO THE FLC. FURTHER, IF THE #1 ENG HAD BEEN ALLOWED TO BURN ALL THE FUEL IN THE #1 TANK, THERE WOULD HAVE BEEN NO WAY TO FEED FUEL TO THAT ENG AND IT WOULD HAVE FLAMED OUT. THE ENRTE STOP AT AMA, OR SOME OTHER ALTERNATE, WAS THEIR ONLY RECOURSE.

Data retrieved from NASA's ASRS site as of July 2007 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.