A challenger ultralight declared an emergency and landed off field due to propeller failure.

Attributes
ACN	396358
Time
Date	199803
Day	Sat
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : zzz
State Reference	US
Altitude	msl bound lower : 1300 msl bound upper : 1300
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : zzz
Operator	general aviation : personal
Make Model Name	Ultralight
Operating Under FAR Part	other : other
Flight Phase	descent other other other
Flight Plan	None
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	other other : other pilot : private
ASRS Report	396358
Person 2
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : private
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	other flight crewa
Resolutory Action	flight crew : declared emergency other
Consequence	other Other
Supplementary
Primary Problem	Aircraft

Narrative:

Aircraft is 2 passenger ultra light with hirth 55 hp power plant. Aircraft had completed 1 full stop landing and takeoff. At pattern altitude (1300 ft) just before turning base leg propeller blade separated along grain line longitudinally from hub to tip. Approximately 2400 RPM (4800 RPM tach). Pilot stated that before flight no damage was noticed. Immediately upon noticing vibration engine was shut down and off field landing was performed. Nose gear strut was bent aft 45 degrees. Aircraft on amphibious floats. No other damage. Callback conversation with reporter revealed the following information: the reporter stated the aircraft propeller was installed by the reporter and was in excellent condition when installed with no nicks, scratches or cracks. The reporter said the aircraft was stored outside with no propeller cover and the heavy rains during the winter may have contributed to the propeller failure. The reporter stated the propeller was made of wood and split from the tip to the hub. The reporter stated the FAA safety inspector examined the aircraft and propeller and has classified it as an incident.

Original NASA ASRS Text

Title: A CHALLENGER ULTRALIGHT DECLARED AN EMER AND LANDED OFF FIELD DUE TO PROP FAILURE.

Narrative: ACFT IS 2 PAX ULTRA LIGHT WITH HIRTH 55 HP PWR PLANT. ACFT HAD COMPLETED 1 FULL STOP LNDG AND TKOF. AT PATTERN ALT (1300 FT) JUST BEFORE TURNING BASE LEG PROP BLADE SEPARATED ALONG GRAIN LINE LONGITUDINALLY FROM HUB TO TIP. APPROX 2400 RPM (4800 RPM TACH). PLT STATED THAT BEFORE FLT NO DAMAGE WAS NOTICED. IMMEDIATELY UPON NOTICING VIBRATION ENG WAS SHUT DOWN AND OFF FIELD LNDG WAS PERFORMED. NOSE GEAR STRUT WAS BENT AFT 45 DEGS. ACFT ON AMPHIBIOUS FLOATS. NO OTHER DAMAGE. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE ACFT PROP WAS INSTALLED BY THE RPTR AND WAS IN EXCELLENT CONDITION WHEN INSTALLED WITH NO NICKS, SCRATCHES OR CRACKS. THE RPTR SAID THE ACFT WAS STORED OUTSIDE WITH NO PROP COVER AND THE HVY RAINS DURING THE WINTER MAY HAVE CONTRIBUTED TO THE PROP FAILURE. THE RPTR STATED THE PROP WAS MADE OF WOOD AND SPLIT FROM THE TIP TO THE HUB. THE RPTR STATED THE FAA SAFETY INSPECTOR EXAMINED THE ACFT AND PROP AND HAS CLASSIFIED IT AS AN INCIDENT.

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.