Accident Overview
On November 20, 2011, at 1030 central standard time, a Cirrus SR20, registration N211CD, sustained substantial damage when it ditched in Lake Pontchartrain approximately four miles north of Lakefront Airport (NEW) in New Orleans, Louisiana. The airline transport rated pilot, who was the sole occupant and owner of the aircraft, sustained minor injuries. The flight departed NEW around 1015 on an instrument flight rules flight plan bound for Dalton Municipal Airport in Dalton, Georgia. Instrument meteorological conditions prevailed at the time of the personal flight conducted under 14 Code of Federal Regulations Part 91.
Pilot Report
According to the pilot, shortly after takeoff from NEW, the No. 2 cylinder head temperature (CHT) increased rapidly, followed by a drop in oil pressure. He immediately turned back toward the airport and requested short vectors for an instrument approach. When the aircraft was about four miles from the runway, the engine "blew" and the propeller seized. The pilot declared an emergency, slowed to 80 knots, and prepared for a water landing. He broke through a low cloud layer at 300 feet, extended the flaps to 15 degrees, reduced airspeed until the stall horn sounded, and deployed the ballistic parachute system. The pilot executed a wings-level landing on the water; the aircraft remained upright. He contacted air traffic control to report his location, donned a life jacket, and exited the airplane. After exiting, he observed oil streaks on the bottom side of the engine cowling. The pilot rested on the tail of the partially submerged aircraft for about forty-five minutes until a local fisherman arrived and rescued him. The only damage noted to the aircraft was a wrinkle in the firewall.
Engine Examination
The engine was examined at Continental Motors Incorporated in Mobile, Alabama, under the supervision of the Investigator-in-Charge. External inspection revealed no obvious impact damage, breaches to the engine case, or leaking oil; the only damage was from water exposure. When the crankshaft flange was manually rotated, it stopped at approximately 300 degrees of travel before locking up.
Disassembly of the engine showed that the No. 2 piston exhibited damage consistent with detonation. The No. 1 and No. 6 piston rods were broken and dark from heat exposure. Other piston rods were also damaged by heat. The crankshaft was fractured into two sections, and pieces of the No. 6 piston cap were found in the oil sump.
The fuel pump and throttle body were flushed to remove water and debris before flushing the metering unit. The fuel metering unit was removed and flushed. A clean glass jar placed under each nozzle captured no visible debris, and each jar appeared to fill uniformly.
Fuel injector nozzles were removed and bench-tested. The No. 2 nozzle tested about two pounds below the minimum value. Shop air was blown through the nozzle with a paper filter to catch debris; after re-testing, the nozzle performed slightly better but still below minimum. A second forced air attempt yielded more debris visually. The nozzle was re-tested but performance did not improve. Electron microscope examination of the filters revealed several specs of black dirt. The other nozzles tested slightly below minimum values, indicating they were operating lean.
A review of maintenance records showed that the fuel injector nozzles were removed and cleaned five days before the accident, on November 13, 2011. The pilot stated he had them cleaned due to a high CHT on the No. 2 cylinder during a prior cross-country flight from Louisiana to Arkansas. After cleaning, the nozzles were reinstalled and two separate engine runs were conducted with no anomalies. The pilot then flew back to Louisiana, a 2.5-hour flight, and everything was "normal." On the subsequent accident flight, the engine failure occurred.