|37000 Feet||Browse and search NASA's
Aviation Safety Reporting System
|Local Time Of Day||1201 To 1800|
|Locale Reference||airport : zzz.airport|
|Altitude||agl single value : 0|
|Operator||general aviation : instructional|
|Make Model Name||PA-44 Seminole Turbo Seminole|
|Operating Under FAR Part||Part 91|
|Flight Phase||landing : roll|
|Function||instruction : instructor|
|Qualification||pilot : multi engine|
pilot : commercial
pilot : instrument
pilot : cfi
|Experience||flight time last 90 days : 80|
flight time total : 500
flight time type : 135
|Function||instruction : trainee|
|Anomaly||aircraft equipment problem : critical|
non adherence : far
non adherence : published procedure
|Independent Detector||other flight crewa|
other flight crewb
|Resolutory Action||none taken : detected after the fact|
|Consequence||faa : investigated|
Flight Crew Human Performance
|Primary Problem||Flight Crew Human Performance|
After a normal training flight; my student and I were in a right traffic pattern for runway 12R. We completed 2 touch-and-goes normally; but on the third landing; the nose gear collapsed after a firm touchdown on the mains. Though there was significant damage to the propellers; this event was classified as an incident. After researching this nose gear; I discovered that there was a service bulletin issued in 2005 for the bolt that connects the upper and lower drag links. This service bulletin (piper service bulletin 1156) indicates that with multiple extensions/retractions; this bolt can develop a weakness in the center of the bolt. On my incident; the bolt was sheared midway along the bolt. There was no airworthiness directive associated with this service bulletin that requires replacement of the bolt every 500 hours; and I discovered it had been 984 hours since the bolt was replaced. Additionally; the training environment requires significantly more gear cycles than the average number that was probably used to determine the 500 hour requirement. An airworthiness directive should be issued for this service bulletin and they should re-examine the 500 hour number. Callback conversation with reporter revealed the following information: the reporter believes the failed scissors bolt contributed to the nose gear failure. Aircraft incurred damage to the propeller; engine and related sheet metal.
Original NASA ASRS Text
Title: A PA44-180 ON A TRAINING FLT PERFORMING TOUCH-AND-GO LNDGS; THE NOSE LNDG GEAR FAILED AFTER A FIRM LNDG. FOUND UPPER AND LOWER NOSE SCISSORS CONNECTION BOLT SHEARED.
Narrative: AFTER A NORMAL TRAINING FLT; MY STUDENT AND I WERE IN A R TFC PATTERN FOR RWY 12R. WE COMPLETED 2 TOUCH-AND-GOES NORMALLY; BUT ON THE THIRD LNDG; THE NOSE GEAR COLLAPSED AFTER A FIRM TOUCHDOWN ON THE MAINS. THOUGH THERE WAS SIGNIFICANT DAMAGE TO THE PROPS; THIS EVENT WAS CLASSIFIED AS AN INCIDENT. AFTER RESEARCHING THIS NOSE GEAR; I DISCOVERED THAT THERE WAS A SVC BULLETIN ISSUED IN 2005 FOR THE BOLT THAT CONNECTS THE UPPER AND LOWER DRAG LINKS. THIS SVC BULLETIN (PIPER SVC BULLETIN 1156) INDICATES THAT WITH MULTIPLE EXTENSIONS/RETRACTIONS; THIS BOLT CAN DEVELOP A WEAKNESS IN THE CTR OF THE BOLT. ON MY INCIDENT; THE BOLT WAS SHEARED MIDWAY ALONG THE BOLT. THERE WAS NO AIRWORTHINESS DIRECTIVE ASSOCIATED WITH THIS SVC BULLETIN THAT REQUIRES REPLACEMENT OF THE BOLT EVERY 500 HRS; AND I DISCOVERED IT HAD BEEN 984 HRS SINCE THE BOLT WAS REPLACED. ADDITIONALLY; THE TRAINING ENVIRONMENT REQUIRES SIGNIFICANTLY MORE GEAR CYCLES THAN THE AVERAGE NUMBER THAT WAS PROBABLY USED TO DETERMINE THE 500 HR REQUIREMENT. AN AIRWORTHINESS DIRECTIVE SHOULD BE ISSUED FOR THIS SVC BULLETIN AND THEY SHOULD RE-EXAMINE THE 500 HR NUMBER. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR BELIEVES THE FAILED SCISSORS BOLT CONTRIBUTED TO THE NOSE GEAR FAILURE. ACFT INCURRED DAMAGE TO THE PROP; ENG AND RELATED SHEET METAL.
Data retrieved from NASA's ASRS site as of January 2009 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.