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|
Attributes | |
ACN | 803500 |
Time | |
Date | 200809 |
Local Time Of Day | 0601 To 1200 |
Place | |
Locale Reference | airport : zzz.airport |
State Reference | US |
Altitude | agl single value : 0 |
Environment | |
Flight Conditions | VMC |
Light | Daylight |
Aircraft 1 | |
Operator | general aviation : personal |
Make Model Name | Small Aircraft Low Wing 1 Eng Retractable Gear |
Operating Under FAR Part | Part 91 |
Flight Phase | ground : taxi |
Flight Plan | IFR |
Person 1 | |
Affiliation | other |
Function | flight crew : single pilot oversight : pic |
Qualification | pilot : private pilot : instrument |
Experience | flight time last 90 days : 38 flight time total : 510 flight time type : 315 |
ASRS Report | 803500 |
Events | |
Anomaly | aircraft equipment problem : critical |
Independent Detector | other flight crewa |
Resolutory Action | none taken : unable |
Consequence | other |
Supplementary | |
Problem Areas | Maintenance Human Performance Aircraft Company |
Primary Problem | Ambiguous |
Narrative:
Aircraft was towed by line personnel the day prior to the incident. Aircraft was started for first time approximately 10 mins before incident. Aircraft was idling at approximately 1000 RPM with parking brake activated while PIC retrieved IFR clearance to ZZZ and completed pre-taxi checklist. PIC called phx ground for taxi clearance and immediately prior to incident. Upon receipt of clearance; PIC hand-signaled line personnel of intention to taxi; at which time personnel walked to the connector to taxiway H and signaled PIC to advance. PIC released parking brakes and advanced throttle to approximately 1300 RPM. Aircraft moved no more than a few inches before nose gear collapsed; with ensuing propeller strike. PIC shut down electrical power and fuel supply; then exited aircraft. Following the incident; PIC took extensive photographs of the nose gear truss that had failed; and consulted with several repair shops with national reputations. The unanimous opinion among them is that the most likely cause is a hard impulse force being applied to the nose gear immediately prior to the incident. They base this judgement on the freshness of the break through solid steel tubes (with no signs of an old developing crack); the location of the break; and the lack of evidence of corrosion. An alternative explanation would be a hard landing and/or porpoise immediately prior to the incident. The PIC testifies that no such hard landing has occurred immediately prior to the incident or; for that matter; in the 2 yrs that he has owned the aircraft.
Original NASA ASRS Text
Title: SMA PILOT REPORTS NOSE GEAR COLLAPSE AT FIRST ATTEMPT TO TAXI AFTER ENGINE START. ACFT HAD BEEN TOWED BY FBO PERSONNEL THE DAY PRIOR.
Narrative: ACFT WAS TOWED BY LINE PERSONNEL THE DAY PRIOR TO THE INCIDENT. ACFT WAS STARTED FOR FIRST TIME APPROX 10 MINS BEFORE INCIDENT. ACFT WAS IDLING AT APPROX 1000 RPM WITH PARKING BRAKE ACTIVATED WHILE PIC RETRIEVED IFR CLRNC TO ZZZ AND COMPLETED PRE-TAXI CHKLIST. PIC CALLED PHX GND FOR TAXI CLRNC AND IMMEDIATELY PRIOR TO INCIDENT. UPON RECEIPT OF CLRNC; PIC HAND-SIGNALED LINE PERSONNEL OF INTENTION TO TAXI; AT WHICH TIME PERSONNEL WALKED TO THE CONNECTOR TO TXWY H AND SIGNALED PIC TO ADVANCE. PIC RELEASED PARKING BRAKES AND ADVANCED THROTTLE TO APPROX 1300 RPM. ACFT MOVED NO MORE THAN A FEW INCHES BEFORE NOSE GEAR COLLAPSED; WITH ENSUING PROP STRIKE. PIC SHUT DOWN ELECTRICAL PWR AND FUEL SUPPLY; THEN EXITED ACFT. FOLLOWING THE INCIDENT; PIC TOOK EXTENSIVE PHOTOGRAPHS OF THE NOSE GEAR TRUSS THAT HAD FAILED; AND CONSULTED WITH SEVERAL REPAIR SHOPS WITH NATIONAL REPUTATIONS. THE UNANIMOUS OPINION AMONG THEM IS THAT THE MOST LIKELY CAUSE IS A HARD IMPULSE FORCE BEING APPLIED TO THE NOSE GEAR IMMEDIATELY PRIOR TO THE INCIDENT. THEY BASE THIS JUDGEMENT ON THE FRESHNESS OF THE BREAK THROUGH SOLID STEEL TUBES (WITH NO SIGNS OF AN OLD DEVELOPING CRACK); THE LOCATION OF THE BREAK; AND THE LACK OF EVIDENCE OF CORROSION. AN ALTERNATIVE EXPLANATION WOULD BE A HARD LNDG AND/OR PORPOISE IMMEDIATELY PRIOR TO THE INCIDENT. THE PIC TESTIFIES THAT NO SUCH HARD LNDG HAS OCCURRED IMMEDIATELY PRIOR TO THE INCIDENT OR; FOR THAT MATTER; IN THE 2 YRS THAT HE HAS OWNED THE ACFT.
Data retrieved from NASA's ASRS site as of May 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.