Pilot Debrief

PORRATA LUIS G RANS S 12XL near Guanica, PR — 2015-12-19

Final reportERA16LA076
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Date
2015-12-19
Location
Guanica, PR, USA
Aircraft
PORRATA LUIS G RANS S 12XL
Registration
N124LP
Category
Airplane
Highest injury
None
Fatalities
0
Phase of flight
Cruise

Probable cause

The pilot/owner's failure to maintain the engine in accordance with manufacturer guidance, which resulted in the undetected corrosion of the power takeoff bearing, subsequent bearing failure, and a total loss of engine power.

NTSB narrative

The sport pilot was conducting a cross-country flight in the light sport airplane when, after about one hour of flight, the engine first experienced a partial loss of power, followed shortly thereafter by a total loss of power. The pilot twice unsuccessfully attempted to restart the engine using the emergency checklist before performing a forced landing to a field. During the landing, the airplane sustained substantial damage to the fuselage. The engine was manufactured about 10 years before the accident and maintenance logs indicated that it had not been overhauled since that time. Examination of the engine revealed that connecting rod bearing material was distributed throughout the power take off (PTO) section of the engine. Furthermore, corrosion was noted on the PTO connecting rod and connecting rod bearing. Although the engine had not yet reached the manufacturer's recommended 300 flight hour time limit for overhaul, it had exceeded the recommended 5-year calendar time limit for overhaul by 5 years. It is likely that a piece of the failed bearing became lodged in the rotary valve disc, which prevented the disc from rotating, and subsequently blocked the air and fuel to the engine, which resulted in a total loss of engine power. Had the engine been overhauled, the corrosion likely would have been discovered and the inflight loss of power prevented.

Analysis

Primary failure mode
Engine power loss
First missed decision gate
Performing a timely engine overhaul as per manufacturer's guidance could have prevented failure.

NTSB coding

Evidence available

  • 5 docket documents
View NTSB final reportView NTSB docket

Docket documents5

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