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|
Attributes | |
ACN | 408447 |
Time | |
Date | 199807 |
Day | Mon |
Local Time Of Day | 1201 To 1800 |
Place | |
Locale Reference | airport : zzz |
State Reference | US |
Altitude | agl bound lower : 0 agl bound upper : 0 |
Environment | |
Light | Daylight |
Aircraft 1 | |
Controlling Facilities | tower : mht |
Operator | common carrier : air carrier |
Make Model Name | MD-88 |
Operating Under FAR Part | Part 121 |
Navigation In Use | Other |
Flight Phase | other |
Flight Plan | None |
Person 1 | |
Affiliation | company : air carrier |
Function | other personnel other |
Qualification | other other : other |
ASRS Report | 408447 |
Person 2 | |
Affiliation | government : faa |
Function | observation : air carrier inspector |
Qualification | other other : other |
Events | |
Anomaly | aircraft equipment problem : critical non adherence : published procedure other anomaly other |
Independent Detector | other flight crewa |
Resolutory Action | other |
Consequence | faa : assigned or threatened penalties Other |
Supplementary | |
Primary Problem | Aircraft |
Air Traffic Incident | other |
Narrative:
Aircraft xyz of the air carrier fleet arrived at my gate (line maintenance) in ZZZ, us. 6 inbound write-ups. Went through all write- ups with pilot. Got to this write-up: excessive vibration and rattle from nosewheels on takeoff roll through retraction. Pilot said vibration was excessive, but it didn't feel like the gear was coming off. I proceeded to open gear doors and inspect torque link bushings (which is a common thing on MD88). Bushings checked good and the rest of the gear. Tires were well in limits, but 1 tire pressure was low. Svced tire to correct pressure. Signed off gear. Aircraft flew to YYY from ZZZ with no problems. From YYY back to ZZZ -- crew wrote up vibration again. Aircraft was laid down and torque link bushings were found with play and replaced, along with both tires and also the steering collar was found to have an excessive gap. I followed maintenance manual for nosewheel shimmy and it says to check torque link assembly for loose or worn bolts or bushings and check all bolts, which I did. Following day, abc of the FAA wanted to know why I didn't do more. My reply was pilot didn't really elaborate on the vibration so I followed maintenance manual, inspected torque links (which were greased the previous leg), which were fully greased by BBB the flight leg previous, and probably took up the play in bushings, which explains why it made 2 flts before it was noticed again. These torque link bushings seem to be a problem on MD88. Callback conversation with reporter revealed the following information: the reporter stated the aircraft arrived with 6 log reports and all were reviewed with the crew before work began. The reporter stated the torque links felt ok for play but had been previously greased and the grease probably took up the excessive play if the torque link bushings were actually the cause of the vibration. The reporter said the corrective action for this report was torque link bushing replacement and both nose tires replaced. The reporter said the nose gear torque link bushings experience heavy excessive wear and are a chronic problem. The reporter states the FAA has assigned a penalty for the reporter's action.
Original NASA ASRS Text
Title: AN MD88 WAS DISPATCHED WITH AN INCORRECT REPAIR FOR A RPT OF EXCESSIVE NOSE GEAR VIBRATION.
Narrative: ACFT XYZ OF THE ACR FLEET ARRIVED AT MY GATE (LINE MAINT) IN ZZZ, US. 6 INBOUND WRITE-UPS. WENT THROUGH ALL WRITE- UPS WITH PLT. GOT TO THIS WRITE-UP: EXCESSIVE VIBRATION AND RATTLE FROM NOSEWHEELS ON TKOF ROLL THROUGH RETRACTION. PLT SAID VIBRATION WAS EXCESSIVE, BUT IT DIDN'T FEEL LIKE THE GEAR WAS COMING OFF. I PROCEEDED TO OPEN GEAR DOORS AND INSPECT TORQUE LINK BUSHINGS (WHICH IS A COMMON THING ON MD88). BUSHINGS CHKED GOOD AND THE REST OF THE GEAR. TIRES WERE WELL IN LIMITS, BUT 1 TIRE PRESSURE WAS LOW. SVCED TIRE TO CORRECT PRESSURE. SIGNED OFF GEAR. ACFT FLEW TO YYY FROM ZZZ WITH NO PROBS. FROM YYY BACK TO ZZZ -- CREW WROTE UP VIBRATION AGAIN. ACFT WAS LAID DOWN AND TORQUE LINK BUSHINGS WERE FOUND WITH PLAY AND REPLACED, ALONG WITH BOTH TIRES AND ALSO THE STEERING COLLAR WAS FOUND TO HAVE AN EXCESSIVE GAP. I FOLLOWED MAINT MANUAL FOR NOSEWHEEL SHIMMY AND IT SAYS TO CHK TORQUE LINK ASSEMBLY FOR LOOSE OR WORN BOLTS OR BUSHINGS AND CHK ALL BOLTS, WHICH I DID. FOLLOWING DAY, ABC OF THE FAA WANTED TO KNOW WHY I DIDN'T DO MORE. MY REPLY WAS PLT DIDN'T REALLY ELABORATE ON THE VIBRATION SO I FOLLOWED MAINT MANUAL, INSPECTED TORQUE LINKS (WHICH WERE GREASED THE PREVIOUS LEG), WHICH WERE FULLY GREASED BY BBB THE FLT LEG PREVIOUS, AND PROBABLY TOOK UP THE PLAY IN BUSHINGS, WHICH EXPLAINS WHY IT MADE 2 FLTS BEFORE IT WAS NOTICED AGAIN. THESE TORQUE LINK BUSHINGS SEEM TO BE A PROB ON MD88. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE ACFT ARRIVED WITH 6 LOG RPTS AND ALL WERE REVIEWED WITH THE CREW BEFORE WORK BEGAN. THE RPTR STATED THE TORQUE LINKS FELT OK FOR PLAY BUT HAD BEEN PREVIOUSLY GREASED AND THE GREASE PROBABLY TOOK UP THE EXCESSIVE PLAY IF THE TORQUE LINK BUSHINGS WERE ACTUALLY THE CAUSE OF THE VIBRATION. THE RPTR SAID THE CORRECTIVE ACTION FOR THIS RPT WAS TORQUE LINK BUSHING REPLACEMENT AND BOTH NOSE TIRES REPLACED. THE RPTR SAID THE NOSE GEAR TORQUE LINK BUSHINGS EXPERIENCE HVY EXCESSIVE WEAR AND ARE A CHRONIC PROB. THE RPTR STATES THE FAA HAS ASSIGNED A PENALTY FOR THE RPTR'S ACTION.
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.