An SA319 helicopter was inadvertently flown past the 50 hour limit for a tail rotor pitch change lin...

Attributes
ACN	571876
Time
Date	200301
Day	Mon
Local Time Of Day	0001 To 0600
Place
Locale Reference	airport : zzz.airport
State Reference	US
Altitude	agl single value : 0
Environment
Flight Conditions	VMC
Light	Dawn
Aircraft 1
Operator	general aviation : personal
Make Model Name	SA319 Alouette III
Operating Under FAR Part	Part 91
Flight Phase	ground : takeoff roll
Flight Plan	None
Person 1
Affiliation	other
Function	flight crew : single pilot oversight : pic
Qualification	pilot : cfi pilot : commercial
Experience	flight time last 90 days : 120 flight time total : 2500 flight time type : 650
ASRS Report	571876
Person 2
Affiliation	other
Function	maintenance : technician
Events
Anomaly	aircraft equipment problem : critical maintenance problem : improper documentation maintenance problem : improper maintenance non adherence : published procedure non adherence : far
Independent Detector	other flight crewa
Resolutory Action	none taken : detected after the fact
Consequence	other other
Factors
Maintenance	contributing factor : schedule pressure contributing factor : weather performance deficiency : scheduled maintenance performance deficiency : non compliance with legal requirements performance deficiency : logbook entry performance deficiency : inspection
Supplementary
Problem Areas	Flight Crew Human Performance Maintenance Human Performance Aircraft Company Environmental Factor
Primary Problem	Maintenance Human Performance

Narrative:

Pilot overflew an airworthiness directive (98-24-35). Airworthiness directive is related to tail rotor pitch change link bearing wear, and is a recurring 50 hours time-in-service requirement. The pilot checks these items during all preflight and postflt inspections for 'no movement allowed (axially and radially)'. This guideline is recommended by the manufacturer, and taught at the factory safety course. The airworthiness directive specifies the use of dial indicator to measure the actual amount of play in the bearing. Scheduling and anticipating maintenance is challenging. In general, maintenance operations are scheduled on wkends. Maintenance is carried out at a facility located in ZZZ1 (approximately .5 hour flight or 1.5 hour drive away). This area is routinely affected by widespread dense 'tule fog,' which blankets the area and frequently does not readily burn off. During the week and wkend prior, the airport was completely fogged in to below even MVFR conditions. (Conditions of 1/4 mi visibility and indefinite ceiling 100 ft prevailed for most of the week and wkend.) maintenance was scheduled based upon the anticipated hours usage for the aircraft, however, several events saw the aircraft flying more frequently and affected the planned schedule. The pilot was unaware of how quickly the inspection due time had arrived. The pilot contracted with another mechanic familiar with the make/model of helicopter and experienced with the airworthiness directive to conduct the inspection. No deficiencies were noted and the aircraft was returned to service. In the mechanic's opinion, the bearings are still very new and show nowhere near the maximum play specified in the airworthiness directive. He felt that, while procedurally incorrect, the overflt of the airworthiness directive did not pose a safety risk. This was largely due to the low total time on the aircraft.

Original NASA ASRS Text

Title: AN SA319 HELI WAS INADVERTENTLY FLOWN PAST THE 50 HR LIMIT FOR A TAIL ROTOR PITCH CHANGE LINK BEARING INSPECTION. REQUIRED AIRWORTHINESS DIRECTIVE INSPECTION.

Narrative: PLT OVERFLEW AN AIRWORTHINESS DIRECTIVE (98-24-35). AIRWORTHINESS DIRECTIVE IS RELATED TO TAIL ROTOR PITCH CHANGE LINK BEARING WEAR, AND IS A RECURRING 50 HRS TIME-IN-SVC REQUIREMENT. THE PLT CHKS THESE ITEMS DURING ALL PREFLT AND POSTFLT INSPECTIONS FOR 'NO MOVEMENT ALLOWED (AXIALLY AND RADIALLY)'. THIS GUIDELINE IS RECOMMENDED BY THE MANUFACTURER, AND TAUGHT AT THE FACTORY SAFETY COURSE. THE AIRWORTHINESS DIRECTIVE SPECIFIES THE USE OF DIAL INDICATOR TO MEASURE THE ACTUAL AMOUNT OF PLAY IN THE BEARING. SCHEDULING AND ANTICIPATING MAINT IS CHALLENGING. IN GENERAL, MAINT OPS ARE SCHEDULED ON WKENDS. MAINT IS CARRIED OUT AT A FACILITY LOCATED IN ZZZ1 (APPROX .5 HR FLT OR 1.5 HR DRIVE AWAY). THIS AREA IS ROUTINELY AFFECTED BY WIDESPREAD DENSE 'TULE FOG,' WHICH BLANKETS THE AREA AND FREQUENTLY DOES NOT READILY BURN OFF. DURING THE WK AND WKEND PRIOR, THE ARPT WAS COMPLETELY FOGGED IN TO BELOW EVEN MVFR CONDITIONS. (CONDITIONS OF 1/4 MI VISIBILITY AND INDEFINITE CEILING 100 FT PREVAILED FOR MOST OF THE WK AND WKEND.) MAINT WAS SCHEDULED BASED UPON THE ANTICIPATED HRS USAGE FOR THE ACFT, HOWEVER, SEVERAL EVENTS SAW THE ACFT FLYING MORE FREQUENTLY AND AFFECTED THE PLANNED SCHEDULE. THE PLT WAS UNAWARE OF HOW QUICKLY THE INSPECTION DUE TIME HAD ARRIVED. THE PLT CONTRACTED WITH ANOTHER MECH FAMILIAR WITH THE MAKE/MODEL OF HELI AND EXPERIENCED WITH THE AIRWORTHINESS DIRECTIVE TO CONDUCT THE INSPECTION. NO DEFICIENCIES WERE NOTED AND THE ACFT WAS RETURNED TO SVC. IN THE MECH'S OPINION, THE BEARINGS ARE STILL VERY NEW AND SHOW NOWHERE NEAR THE MAX PLAY SPECIFIED IN THE AIRWORTHINESS DIRECTIVE. HE FELT THAT, WHILE PROCEDURALLY INCORRECT, THE OVERFLT OF THE AIRWORTHINESS DIRECTIVE DID NOT POSE A SAFETY RISK. THIS WAS LARGELY DUE TO THE LOW TOTAL TIME ON THE ACFT.

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.

An SA319 helicopter was inadvertently flown past the 50 hour limit for a tail rotor pitch change link bearing inspection. Required airworthiness directive inspection.