Narrative:

Nosewheel shimmy during rollout after normal landing. Unable to taxi with nosewheel steering. Had to be towed into gate. Runway closed approximately 20 mins. On inspection found the torque link that connects nosewheel steering to be disconnected. (Pin was out). Apparently, the pin was installed improperly and worked itself out en route. Taxi out was normal and push crew advised torque link was connected after pushback on our departure. Callback conversation with reporter revealed the following information: the captain was flying a B727-200 when the torque link pin came out of the torque link connection and the aircraft lost its nosewheel steering capability. Upon inspection, a mechanic found the pin, still attached to its restraining cable, hanging from the nosewheel strut. The pin was in good condition, however, the locking mechanism was not apparently used. The pin has a pivoting piece of flat stock at its end that the ground crew operator should press until it is 90 degrees to the pin shank so that the pin will not move out of the torque link connection hole. The mechanic said that he could not fault the pin or the torque linkage. The reporter said that the company had recently expanded and this caused them to hire a number of new ground personnel who had not been trained very well. There is a major ground training effort underway since this and several other incidents, according to the reporter. The captain said that he first noticed the shimmy at about 90 KTS, but he applied full nose up elevator to take the pressure off of the nose wheel and did not have the problem again until the aircraft was much slower. Then as he was trying to maneuver towards the high speed taxiway the nosewheel 'cocked' 90 degrees.

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Original NASA ASRS Text

Title: ACFT EQUIP PROB -- ACR LOSES NOSEWHEEL STEERING DURING LNDG ROLL.

Narrative: NOSEWHEEL SHIMMY DURING ROLLOUT AFTER NORMAL LNDG. UNABLE TO TAXI WITH NOSEWHEEL STEERING. HAD TO BE TOWED INTO GATE. RWY CLOSED APPROX 20 MINS. ON INSPECTION FOUND THE TORQUE LINK THAT CONNECTS NOSEWHEEL STEERING TO BE DISCONNECTED. (PIN WAS OUT). APPARENTLY, THE PIN WAS INSTALLED IMPROPERLY AND WORKED ITSELF OUT ENRTE. TAXI OUT WAS NORMAL AND PUSH CREW ADVISED TORQUE LINK WAS CONNECTED AFTER PUSHBACK ON OUR DEP. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE CAPT WAS FLYING A B727-200 WHEN THE TORQUE LINK PIN CAME OUT OF THE TORQUE LINK CONNECTION AND THE ACFT LOST ITS NOSEWHEEL STEERING CAPABILITY. UPON INSPECTION, A MECH FOUND THE PIN, STILL ATTACHED TO ITS RESTRAINING CABLE, HANGING FROM THE NOSEWHEEL STRUT. THE PIN WAS IN GOOD CONDITION, HOWEVER, THE LOCKING MECHANISM WAS NOT APPARENTLY USED. THE PIN HAS A PIVOTING PIECE OF FLAT STOCK AT ITS END THAT THE GND CREW OPERATOR SHOULD PRESS UNTIL IT IS 90 DEGS TO THE PIN SHANK SO THAT THE PIN WILL NOT MOVE OUT OF THE TORQUE LINK CONNECTION HOLE. THE MECH SAID THAT HE COULD NOT FAULT THE PIN OR THE TORQUE LINKAGE. THE RPTR SAID THAT THE COMPANY HAD RECENTLY EXPANDED AND THIS CAUSED THEM TO HIRE A NUMBER OF NEW GND PERSONNEL WHO HAD NOT BEEN TRAINED VERY WELL. THERE IS A MAJOR GND TRAINING EFFORT UNDERWAY SINCE THIS AND SEVERAL OTHER INCIDENTS, ACCORDING TO THE RPTR. THE CAPT SAID THAT HE FIRST NOTICED THE SHIMMY AT ABOUT 90 KTS, BUT HE APPLIED FULL NOSE UP ELEVATOR TO TAKE THE PRESSURE OFF OF THE NOSE WHEEL AND DID NOT HAVE THE PROB AGAIN UNTIL THE ACFT WAS MUCH SLOWER. THEN AS HE WAS TRYING TO MANEUVER TOWARDS THE HIGH SPD TXWY THE NOSEWHEEL 'COCKED' 90 DEGS.

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.