Power levers stuck on final approach.

Attributes
ACN	297587
Time
Date	199502
Day	Mon
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : ewr
State Reference	NJ
Altitude	agl bound lower : 200 agl bound upper : 600
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : ewr tower : stl
Operator	common carrier : air carrier
Make Model Name	B737-300
Operating Under FAR Part	Part 121
Navigation In Use	Other Other
Flight Phase	descent : approach
Route In Use	approach : straight in
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 200 flight time total : 15000 flight time type : 8000
ASRS Report	297587
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : unspecified other flight crewa
Resolutory Action	flight crew : overcame equipment problem
Consequence	Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

On coupled approach runway 4F to ewr, aircraft started to get slow. Pushing the throttles did not move them. They appeared stuck due to interlock or autothrottle clutch. Disengaged autothrottle, then vigorously pushed and pulled throttles till they broke free. Descended below GS to maintain speed and landed normally. Callback conversation with reporter revealed the following information: the reporter flies the B-737-300 for a major united states air carrier on domestic rtes. He has never seen a problem like this before. He does not think that this could have been caused by ice as the throttles were moving properly earlier in the approach. The logbook was written off as 'bite check ok,' but the aircraft was then taken OTS for further testing. The reporter has extracted a promise from his director of operations to get some feedback on what caused this anomaly, and he will pass this information on to the ASRS. The throttles were at or near idle when they stuck. The reporter thinks that he broke them loose going towards the closed position, then forward. He did not ask for help from his very new first officer. The reporter believes that he used 'about 60 pounds force' to break the throttles loose.

Original NASA ASRS Text

Title: PWR LEVERS STUCK ON FINAL APCH.

Narrative: ON COUPLED APCH RWY 4F TO EWR, ACFT STARTED TO GET SLOW. PUSHING THE THROTTLES DID NOT MOVE THEM. THEY APPEARED STUCK DUE TO INTERLOCK OR AUTOTHROTTLE CLUTCH. DISENGAGED AUTOTHROTTLE, THEN VIGOROUSLY PUSHED AND PULLED THROTTLES TILL THEY BROKE FREE. DSNDED BELOW GS TO MAINTAIN SPD AND LANDED NORMALLY. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR FLIES THE B-737-300 FOR A MAJOR UNITED STATES ACR ON DOMESTIC RTES. HE HAS NEVER SEEN A PROB LIKE THIS BEFORE. HE DOES NOT THINK THAT THIS COULD HAVE BEEN CAUSED BY ICE AS THE THROTTLES WERE MOVING PROPERLY EARLIER IN THE APCH. THE LOGBOOK WAS WRITTEN OFF AS 'BITE CHK OK,' BUT THE ACFT WAS THEN TAKEN OTS FOR FURTHER TESTING. THE RPTR HAS EXTRACTED A PROMISE FROM HIS DIRECTOR OF OPS TO GET SOME FEEDBACK ON WHAT CAUSED THIS ANOMALY, AND HE WILL PASS THIS INFO ON TO THE ASRS. THE THROTTLES WERE AT OR NEAR IDLE WHEN THEY STUCK. THE RPTR THINKS THAT HE BROKE THEM LOOSE GOING TOWARDS THE CLOSED POS, THEN FORWARD. HE DID NOT ASK FOR HELP FROM HIS VERY NEW FO. THE RPTR BELIEVES THAT HE USED 'ABOUT 60 LBS FORCE' TO BREAK THE THROTTLES LOOSE.

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.