MIA05FA040

The pilot stated that when the airplane was 3 miles east of the shoreline, at 3,000 feet, he felt a short tremor in the left engine followed by loss of power from the left engine. The pilot elected to return to the departure airport while declaring an emergency to air traffic control. During the process of securing the left engine the pilot noticed the propeller did not feathered and the airplane was descending quickly. He maneuvered the airplane and ditched in a lake. On September 26, 2003 engine s/n: 34592 was removed from the accident airplane due to high oil consumption with 1,225 hours of time in service. It was reportedly preserved and stored at the operator's warehouse. The mechanic who reportedly preserved the engine stated he followed the steps in the manual that was provided by the operator. On October 27, 2004 the left engine, s/n: NK510332, which was producing metal for months, was removed and engine s/n: 34592 was taken out of preservation and installed in the left position on the accident airplane with a new overhauled propeller assembly. On November 06, 2004, the left engine's, s/n: 34592, propeller governor was replaced due to the left propeller slow to response to power setting. During the post accident engine examination, the engine's main oil screen was observed with deposits of metal flakes and fragments, the oil scavenge pump would not rotate and had deposits of metal fragments internally; the engine was seized and wound not rotate. Catastrophic damage was observed to the accessories drive gears, oil transfer tube, and protection covers in the front accessory area. It was observed during a visual inspection of the crankshaft and bearings, including the front journal and front crankpin had damaged and sections of their respective bearings missing. The master rod bearing had incurred a catastrophic failure. Several cylinders skirts were found with impact marks from piston rods. Before removing the propeller assembly from the engine, the propeller feather system was flush with fresh oil and pressured with a feathering pump; the propeller blades were observed moving toward the feather position. Examination of the propeller assembly revealed metal contamination throughout the system; the propeller's governor screen gasket was clogged with metal contamination. The maintenance manual provided by the operator used for the engine preservation details several tasks required to be accomplished to the engine for proper engine preservation (i.e. thrust bear, cylinder, and propeller shaft treatments), which the mechanic did not mention he performed. No documentation for inspection and condition status of the dehydrator plugs were available. Documentation for flushing of contamination from the metal producing engine, s/n NK510332, was not available nor knowledge by the operator if since a process was preformed to the left engine's oil tank and its system before installation of engine s/n: 34592. An FAA review of the cargo manifest discovered two different manifest weights. The cargo manifest obtained at the accident scene showed a total of 267 pieces of cargo annotated at a total weight of 10, 837 lbs. The sealed cargo manifest package showed a total of 267 pieces of cargo annotated at a total weight of 14,182 lbs. The maximum payload weight for the accident airplane is 13,586 lbs.

History of Flight

On December 4, 2004, about 0851 eastern standard time, a Convair 340, N41626, registered to and operated by Miami Air Lease, a Title 14 CFR Part 125 certificate holder, ditched in Maule Lake, North Miami Beach, Florida, following loss of power from the number one engine, while carrying cargo for a Title 14 CFR Part 135 cargo operator, from Opa Locka Airport, Opa Locka, Florida, to Nassau, Bahamas. Visual meteorological conditions prevailed at the time and an instrument flight rules flight plan was filed. The commercial-rate pilot and the airline transport-rated copilot were not injured. The airplane incurred substantial damage. The flight originated from Opa Locka, the same day, about 0840.

The pilot stated that the departure from Opa Locka and climb to 3,000 feet were uneventful. When 3 miles east of the shoreline, at 3,000 feet, he felt a short tremor in the left engine. He scanned the engine's instruments and all "seemed perfect". Right after the scan, the tremor returned, followed by loss of power from the left engine. The pilot elected to return to the departure airport while declaring an emergency to air traffic control (ATC). He and the copilot initiated emergency procedures; at that time, the pilot noticed the propeller on the left engine would not go to the feathered position. Upon completion of the emergency checklist the aircraft's altimeter was indicating 1,200 feet and the airplane was descending quickly. Realizing he was not going to reach the airport, he advised ATC and saw Maule Lake to the right of airplane. He maneuvered the airplane from a west to an east heading toward the lake. Before ditching the airplane in the lake, it passed over power lines and clipped trees.

Personnel Information

The pilot-in-command who was seated in the left seat was the holder of a commercial pilot certificate with ratings for airplane multi-engine land, instrument airplane, CV-220, CV-340, CV-440 and private privileges airplane single-engine land. He was issued a first class medical certificate on December 18, 2003, with no limitation. Pilot's flight times as documented with operator's personnel records consisted of 3,100 hours total time in all aircraft, 2,098 of those hours as pilot-in-command, and 2,400 hours in the accident airplane make and model. In the prior 90 days before the accident he had flown 78 hours and in the prior 30 days he had flown 31 hours.

The copilot who was seated in the right seat was the holder of an airline transport pilot certificate with ratings for airplane multi-engine land and commercial privileges airplane single-engine land, rotorcraft-helicopter. Copilot's flight times as documented with operator's personnel records consisted of 9,169 hours total time in all aircraft, 3,823 hours as pilot in command, and 964 hours in the accident airplane make and model. In the prior 90 days before the accident he had flown 54 hours and in the prior 30 days he had flown 29 hours.

Aircraft Information

FAA records indicate the accident airplane was manufactured in 1955 as a military C-131B, serial number (s/n) 53-7822. In 1992 an FAA airworthiness certificate was issued changing the model and serial number of the airplane to a Convair 340-70, s/n 274, registration number N41626, in the transport category. The airplane was registered to Miami Air Lease in December of 1993. The airplane was equipped with two Pratt & Whitney (P&W) R2800-103W engines and two Hamilton Standard model MD 43E60/6895A propellers.

According to the Miami Air Lease Incorporated FAA approved Airplane Maintenance Program and records, the accident airplane was on a continuous airworthiness maintenance program. The last inspection was a continuous airworthiness inspection "A" on November 27, 2004, at total airframe time of 18,465 hours, which was accomplished 8 hours before the accident flight. The last unscheduled maintenance was performed on December 02, 2004, to the left engine s/n: 34592; the number two cylinder was replaced, at total airframe time of 18,470 hours.

The operator's maintenance records for the left engine, s/n: 34592, indicated the engine was overhauled on March 3, 1998 and installed on the accident airplane. In May of 1998 the engine was removed due to high oil consumption and repaired at the same facility which performed the overhaul; thereafter installed on the accident airplane. In November of 1999 the engine had the blower assembly repaired by the overhaul facility. The engine was installed in the right engine position of the accident airplane with 809 hours total time in service, on August 31, 2002. No documentation for the engine's activity was available between those two dates. On September 26, 2003 the engine was removed, from the right position of N41626, due to high oil consumption and document as "for company convenience" with a total time in service of 1225 hours. Immediately following the removal the engine was reportedly preserved and taken to the operator's warehouse for storage.

The mechanic who preserved the left engine stated that he had done previous maintenance work for operator and was asked if he would prepared an engine for preservation for them. The operator explained they picked up a new route and wanted a low time engine on the airplane to replace the high time engine that was on the airplane. He consulted with an employee at the facility where he worked to see if the same corrosion inhibitor oil was still being used to preserve engines. The maintenance manual for the engine preservation was provided by the operator along with the special hydro spark plugs, which appeared to be new and unused. The mechanic purchased and supplied the corrosion inhibitor oil. He noted the engine, s/n: 34592, that was removed had noticeable oil leaks and appeared to be leaking for sometime. The mechanic stated he followed the steps as outlined in the manual. He first drained the existing oil from the engine. He premixed new engine oil with corrosion inhibitor and pumped into the engine oil system under pressure. Five to 8 gals of mixed oil was pumped into the engine before it flowed out from the nose dome section of the engine. He removed the spark plugs from all the cylinders and replaced them with the hydro plugs. The engine was then covered with plastic and taken to the Miami Air Lease warehouse. The operator did not indicate how long the engine was going to be kept in storage. The mechanic went to the operator's warehouse to document the preservation in the engine's logbook. The engine's logbook was locked in a cabinet and the person with the key was out of town. The mechanic documented the engine preservation on the back of the airplane's flight log sheet dated September 26, 2003, which documented the removal and installation of that right engine.

A spectrometric engine oil analysis report dated July 2, 2004 for the left engine, s/n: NK510332, indicated the oil contained metal. On October 27, 2004 the left engine, s/n: NK510332, was removed and engine s/n: 34592 was taken out of storage and installed in the left position of the accident airplane. No documentation was available on what depreservation procedures were performed to the engine prior to installation. A newly overhauled propeller assembly, s/n: AP7274, was installed on the engine during the installation. During the engine performance check run, oil leaks were found and corrected as document in the engine's logbooks. On November 06, 2004, the left engine's propeller governor was replaced due to left propeller slow to response to power setting and propeller governor, s/n: WH97748 was installed.

Weight & Balance

The FAA reviewed the cargo manifest and weight and balance sheet for the accident flight. The cargo manifest obtained at the accident scene showed the owner of the cargo as Miami Air Lease, Inc., port of lading Miami International Airport and port of unlading Nassau International Airport, dated December 4