N73115

HISTORY OF FLIGHT

On July 25, 2012, about 1420 Atlantic time zone (AST), a Cessna 172M, N73115, was substantially damaged when it impacted the water near Fernando Luis Ribas Dominicci Airport (TJIG), San Juan, Puerto Rico. Visual meteorological conditions prevailed and a visual flight rules flight plan had been filed. The private pilot was fatally injured. The personal flight was conducted under the provisions of Title 14 Code of Federal Regulations Part 91. The flight originated from Antonio/Nery/Juarbe Pol Airport (TJAB), Arecibo, Puerto Rico.

According to numerous eyewitness reports, the airplane appeared to be maintaining level flight and subsequently banked to the right, as viewed from behind, descended, and then impacted the water in a right-wing-down attitude. One eyewitness, located in an aircraft that was following the accident airplane on final approach, reported that the airplane "made some zigzagging" prior to it banking to the right. The airplane was observed impacting the water's surface with the right wing tip. The airplane then cartwheeled and disappeared below the water's surface.

According to video taken of a security video monitor, from a camera mounted on a terminal building on the southwest side of the bay, the airplane banked to the right and remained in a continuous bank. The airplane turned about 180 degrees of heading change, facing the direction of travel prior to impacting the water. The airplane was observed impacting the water in a right-wing-low attitude and, within about 2 seconds, disappeared below the water's surface.

PERSONNEL INFORMATION

According to Federal Aviation Administration (FAA) records, the pilot held a private pilot certificate with an airplane, single engine land rating. The most recent logbook entry that was located, dated September 30, 2011, indicated he had 1,150.9 total hours of flight time. According to information provided on his most recent third class medical certificate application, issued March 3, 2012, he reported 1,175 total hours of flight time. The medical certificate was issued with a limitation for the requirement to wear corrective lenses, and not valid for any class after.

AIRCRAFT INFORMATION

According to FAA records, the airplane was issued an airworthiness certificate on May 14, 1976 and was registered to the pilot on December 2, 2002. It was equipped with a Lycoming O-320-E2D engine, serial number L-45584-27A. A review of copies of maintenance logbook records showed an annual inspection was completed April 13, 2012, at a recorded tachometer reading of 2,999 hours, and engine time since overhaul of 2,928.0 hours. The tachometer and Hobbs meter were observed at the accident site and indicated 3,009.6 hours and 586.0 flight hours, respectively. The most recent entry that specifically stated when any control cables were lubricated was recorded on January 22, 2010, at a tachometer reading of 2,913.2 hours, and that wan an engine logbook entry.

According to an airframe and powerplant (A&P) mechanic, he performed most of the maintenance and on the day of the accident he serviced the nosewheel strut, which was "low." He also performed the last annual inspection; however, he was unsure of the date. According to the inspection authorization (IA) mechanic who signed off on the annual inspection, it was completed about six months prior to the accident.

METEOROLOGICAL INFORMATION

The 1422 recorded weather observation at TJIG included wind from 110 degrees at 8 knots, visibility 10 miles or greater, scattered clouds at 4,000 feet above ground level (agl), temperature 32 degrees C, dew point 24 degrees C and barometric altimeter setting 30.03 inches of mercury.

COMMUNICATION

At 1413:00, the pilot made his initial contact with the TJIG Federal Contract Air Traffic Control Tower controller and was subsequently told to make a straight in approach to runway nine and report at the Levittown water tank.

At 1416:28, the pilot reported abeam the Levittown water tank.

At 1418:13, the pilot stated, "november one one five tower."

At 1418:15, the local controller replied, "november one one five tower."

At 1418:17, the pilot replied, "i think i got my aileron cable broken ah i am unable to maintain level flight so i'll continue the descent and land."

At 1418:27, the tower controller replied, "november one one five you're cleared to land runway niner wind one one zero at six do you require any assistance."

At 1418:33, the pilot stated, "i don't know i guess not." No further recorded transmissions were received from the accident airplane.

At 1422:09, the pilot of another aircraft, which was in the area, reported that the airplane had crashed into the water.

WRECKAGE AND IMPACT INFORMATION

According to U.S. Coast Guard channel charts, the airplane was found submerged in approximately 44 feet of water, 1,490 feet from the threshold of runway 9, the intended landing runway. The wreckage debris was located slightly to the south of the extended centerline for runway 9. The main wreckage was located in a generally compact area. According to photographs provided to the NTSB during the night recovery operation, the airplane came to rest inverted and was resting on the floor of the bay.

Right Wing

The right wing remained attached to the forward attachment point and all access panels remained in place. Crush damage was evident on the outboard 3 feet, 3 inches of the wing structure . The trailing edge wing root exhibited compression fractures from the attachment point of the fuselage, outward for about 4 feet, 1 inches. The outboard 21 inches of the right wing aileron was bent slightly in the negative direction, and the inboard section of the wing flap, about 24 inches in length, exhibited damage that was similar to crush damage. The wing strut was bent in the negative direction about 27 inches from the wing attach point. The right flap drive motor worm gear was measured at 2.5 inches, which correlated to a 10-degree flap position. The aileron and flap remained attached to their respective attachment points. The interconnect control cable to both ailerons exhibited broomstrawing and the control cable associated with the right aileron was separated in a manner consistent with tensile overload. The top left doorpost pulley exhibited signs of scoring on the pulley rim. A section of the right aileron control direct cable, which exhibited signatures consistent with corrosion at the failure point, and its associated pulley, were removed and sent to the NTSB Materials Laboratory for examination. The other cables did not exhibit signs of excessive corrosion at the failure points. All cables appeared to have had a lubricant applied and were oily in nature; however, a section of cable on the aileron control direct cable at the fracture point was devoid of lubrication.

Empennage

The empennage exhibited impact damage and fractures aft of the cargo compartment and remained attached to the cabin area by rudder and elevator cables. Continuity to the rudder from the rudder pedals was confirmed. Continuity from the elevator to the empennage fracture point and then forward to the base of the cockpit control column was confirmed. The trim tab was found at the 10-degrees trailing edge up setting.

The emergency locator transmitter (ELT) remained secured and attached to the sidewall of the empennage. The ELT switch was found in the "ON" position; however, no reports of an ELT activation were reported. The ELT had a label affixed with the following notation, "Replace Battery June 2014." Examination of the ELT revealed saltwater intrusion and corrosion on the internal mechanism and batteries.

Left wing

The left wing remained attached at the attachment point, and all access panels remained in place. The outboard 8 feet, 10 inches, as measured from the wingtip, of the leading edge exhibited crush damage. The aileron and flap remained attached. The wing flap position could not be determined due to cable overload and the flap moved freely in the flap track. The inboard 28 inches of the wing leading edge, as measured from the wing root, exhibited crush damage. The aileron was slightly bent in an area 53 to 59 inches from the inboard edge. Cables associated with the aileron exhibited signs of tensile overload or broomstrawing. All cables associated with the flight controls appeared to be oily in nature and were lubricated.

Engine

The engine remained attached to the firewall by five electrical wires, the oil line, and a fuel line; all engine mount brackets were fractured from impact. The engine was separated from the airframe to facilitate examination. The magnetos remained attached to the engine. They were removed and rotated smoothly when manually turned. The left magneto impulse coupling was observed to be operating; however, spark was could not be produced. Salt water corrosion was observed on in the interior and exterior of the unit. The oil filter was removed and oil was present as well as salt water.

The bottom spark plugs were removed and the engine was rotated using the propeller blade attached to the hub. Continuity was confirmed from the propeller hub through the rear accessory pad. Compression was noted on all cylinders and during rotation, salt water expelled through the No. 1 cylinder spark plug. Thumb compression was verified on all cylinders. Cylinder No.2 exhibited weaker suction and compression, as compared to the other three cylinders. The valve cover was removed, and both valves were observed operating as normal. The bottom spark plugs were removed. According to the Champion Spark Plug inspection chart, the spark plugs appeared light gray in color with normal wear.

The propeller remained attached with no S-bending or tip curling noted; however, the propeller spinner exhibited slight torsional twisting and crush damage.

The fuel strainer remained attached and was disassembled. The fuel screen exhibited signs of salt water intrusion and was partially cov...