A C-206's io-550 crankshaft cracked in flight; spraying oil on the aircraft's left windshield. The p...

Attributes
ACN	1024646
Time
Date	201207
Local Time Of Day	1201-1800
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	Cessna Stationair/Turbo Stationair 6
Operating Under FAR Part	Part 91
Flight Phase	Cruise
Route In Use	Direct
Flight Plan	IFR
Component
Aircraft Component	Crankshaft
Person 1
Function	Pilot Flying
Qualification	Flight Crew Multiengine Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Last 90 Days 50 Flight Crew Total 8300 Flight Crew Type 150
Events
Anomaly	Aircraft Equipment Problem Critical

Narrative:

En route in cruise; noted a slight wisp of oil on windshield. While contemplating the situation; noticed a slight increase in oil flow. Canceled IFR (was IFR) and opted direct to nearest airport approximately 40 miles. At 30 miles; oil flow became heavier. Started looking for a place to park it. Saw a nice straight road ahead and headed for it. By 20 miles; very heavy oil flow. A precautionary landing seemed in order. Set up an approach to the north. Due to the heavy oil flow; pilot flying could not see through the windshield. Right seat had better visibility. Oil flow was heavier on left side than right seat. As pilot in command; I relinquished control to right seat pilot (ATP; CFI with total time 25;000). Landed uneventfully. After landing; cause of leak was discovered as spiral crack in crankshaft over 1/2 round. Engine was a factory new io-550 and had accumulated 138.7 hours.

Original NASA ASRS Text

Title: A C-206's IO-550 crankshaft cracked in flight; spraying oil on the aircraft's left windshield. The pilot gave control to the experienced pilot in the right seat; who made a successful off airport landing.

Narrative: En route in cruise; noted a slight wisp of oil on windshield. While contemplating the situation; noticed a slight increase in oil flow. Canceled IFR (was IFR) and opted direct to nearest airport approximately 40 miles. At 30 miles; oil flow became heavier. Started looking for a place to park it. Saw a nice straight road ahead and headed for it. By 20 miles; very heavy oil flow. A precautionary landing seemed in order. Set up an approach to the north. Due to the heavy oil flow; pilot flying could not see through the windshield. Right seat had better visibility. Oil flow was heavier on left side than right seat. As pilot in command; I relinquished control to right seat pilot (ATP; CFI with total time 25;000). Landed uneventfully. After landing; cause of leak was discovered as spiral crack in crankshaft over 1/2 round. Engine was a factory new IO-550 and had accumulated 138.7 hours.

Data retrieved from NASA's ASRS site as of July 2013 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.

A C-206's io-550 crankshaft cracked in flight; spraying oil on the aircraft's left windshield. The pilot gave control to the experienced pilot in the right seat; who made a successful off airport landing.