Narrative:

While leveling off at FL290 after making idle power descent from FL370, large throttle stagger was noticed as automatic throttle began to increase power toward cruise. The #2 power lever was lagging well behind the #1 power lever. When it became apparent that #2 was not going to catch up with #1, automatic throttle was disconnected and an attempt was made to manually even up the levers, however, the #2 lever could not be moved forward of approximately the 12 O'clock position. Light to moderate force was used several times in an attempt to increase power beyond 12 O'clock to no avail. Since the power on that engine was limited to approximately 50 percent N1, the power on #1 engine was increased to compensate. An emergency was declared with ATC and we received priority handling to phx. Maintenance control was notified and the flight attendants were briefed. The decision was made to operate that engine at whatever power could be obtained. The '1 engine inoperative landing' checklist was consulted and the appropriate items were accomplished. Several more times during our approach and landing at phx, attempts were made, to no avail, to increase the power on the #2 engine beyond the 12 O'clock position. An uneventful landing was made at phx. The #2 power lever movement remained restr until several mins after engine shutdown at gate, then mysteriously became free again.

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Original NASA ASRS Text

Title: EMER DECLARED WHEN ACR MLG EXPERIENCES AN ACFT EQUIP PROB MALFUNCTION.

Narrative: WHILE LEVELING OFF AT FL290 AFTER MAKING IDLE PWR DSCNT FROM FL370, LARGE THROTTLE STAGGER WAS NOTICED AS AUTO THROTTLE BEGAN TO INCREASE PWR TOWARD CRUISE. THE #2 PWR LEVER WAS LAGGING WELL BEHIND THE #1 PWR LEVER. WHEN IT BECAME APPARENT THAT #2 WAS NOT GOING TO CATCH UP WITH #1, AUTO THROTTLE WAS DISCONNECTED AND AN ATTEMPT WAS MADE TO MANUALLY EVEN UP THE LEVERS, HOWEVER, THE #2 LEVER COULD NOT BE MOVED FORWARD OF APPROX THE 12 O'CLOCK POS. LIGHT TO MODERATE FORCE WAS USED SEVERAL TIMES IN AN ATTEMPT TO INCREASE PWR BEYOND 12 O'CLOCK TO NO AVAIL. SINCE THE PWR ON THAT ENG WAS LIMITED TO APPROX 50 PERCENT N1, THE PWR ON #1 ENG WAS INCREASED TO COMPENSATE. AN EMER WAS DECLARED WITH ATC AND WE RECEIVED PRIORITY HANDLING TO PHX. MAINT CTL WAS NOTIFIED AND THE FLT ATTENDANTS WERE BRIEFED. THE DECISION WAS MADE TO OPERATE THAT ENG AT WHATEVER PWR COULD BE OBTAINED. THE '1 ENG INOP LNDG' CHKLIST WAS CONSULTED AND THE APPROPRIATE ITEMS WERE ACCOMPLISHED. SEVERAL MORE TIMES DURING OUR APCH AND LNDG AT PHX, ATTEMPTS WERE MADE, TO NO AVAIL, TO INCREASE THE PWR ON THE #2 ENG BEYOND THE 12 O'CLOCK POS. AN UNEVENTFUL LNDG WAS MADE AT PHX. THE #2 PWR LEVER MOVEMENT REMAINED RESTR UNTIL SEVERAL MINS AFTER ENG SHUTDOWN AT GATE, THEN MYSTERIOUSLY BECAME FREE AGAIN.

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.