N7376Y

HISTORY OF FLIGHTOn May 27, 2017, about 1101 Alaska daylight time, a Piper PA-30, airplane, N7376Y, collided with the ground shortly after a low-level pass over a remote airstrip at Glacier Point, which is located 12 miles southeast of Haines, Alaska. The pilot and a pilot-rated passenger in the right front seat were fatally injured, and a rear-seated passenger was seriously injured. The airplane was registered to the pilot who was operating it under the provisions of Title 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions prevailed at the time of the accident, and a flight plan was not filed. The flight originated from Juneau International Airport (PAJN), Juneau, Alaska, about 1015 and was destined for Haines Airport (PAHN), Haines, Alaska.

An eyewitness located across Chilkat Inlet, which was about 2 miles east of the shoreline of Glacier Point, and using binoculars saw the accident airplane flying northbound at tree level near the airstrip. He stated that, as the airplane reached the end of the airstrip, it dropped in altitude, banked to the right, and impacted the shoreline in a right-wing-down, nose-down attitude. The airplane came to rest near the edge of a canal about 1/4-mile northeast of the north end of the airstrip (See Figure 1). The eyewitness and three other people responded to the accident site by boat and called local authorities when cell coverage was available when they were about halfway across the canal. According to the eyewitness, as they arrived at the accident site, the rear-seated passenger was the only airplane occupant who was responsive, but he could not be removed from the airplane. Within minutes, tidal water was surrounding and flooding the airplane. A tractor brought to the site from a local tour facility was used to drag the airplane to shallow water. Local authorities arrived soon after and extricated the passengers.

Figure 1-Aerial Image of the Accident Site

According to the rear-seated passenger aboard the accident airplane, about 20 minutes into the flight, the pilot intentionally shut down the right engine to demonstrate how to restart the engine during flight. Despite several attempts, the engine would not restart with electrical power. The pilot then made several attempts to air start the engine by gaining altitude and then diving the airplane down to use airflow to assist in rotating the engine. After two unsuccessful attempts to air start the engine, the pilot decided to descend to a lower altitude, fly to the airstrip at Glacier Point, and use the battery booster (which was located in the baggage compartment) after landing to start the engine. As the airplane approached the airstrip, the pilot made a low-level pass to check the condition of the airstrip surface; this was the last thing the passenger remembered about the flight.

A friend of the pilot reported that he flew with the accident pilot in the accident airplane on the day before the accident. The friend stated that he and the pilot were preparing to depart PAJN for a planned flight to Gustavus Airport (PAGS), Gustavus, Alaska. As the airplane was taxiing to depart, the left engine "stalled" on the taxiway, and the pilot could not restart the engine using the starter due to low electrical power from the battery. They taxied back to the pilot's hangar, where they removed a battery from his hangered floatplane and installed it in the accident airplane. Despite these actions, both engines could not be started. The friend said that the floatplane battery did not supply enough electrical power to start the airplane engine. The pilot then parked his motor vehicle near the airplane, plugged in the airplane's jumper cables, and successfully jumpstarted both engines from the vehicle's battery. The pilot and his friend departed PAJN on an uneventful flight to PAGS. The friend stated that the pilot told him that he normally had a handheld battery booster in the airplane but that he had loaned it to the ground personnel at PAJN because they had a hard time starting the airport's fuel truck. PERSONNEL INFORMATIONThe pilot, age 29, held a private pilot certificate with multiengine land and single-engine land and sea ratings. The pilot's most recent FAA third-class airman medical certificate was issued on January 30, 2013, with no limitations. On his medical application, the pilot reported that his total flight experience during the previous 6 months was 0 hours. The pilot's logbook was not located during the investigation. AIRCRAFT INFORMATIONThe airplane, which was manufactured in 1964, was an all-metal multiengine airplane that incorporated a semi-monocoque fuselage and empennage design. The airplane was equipped with fully cantilevered wings, electrically operated wing flaps, and electrically operated retractable tricycle landing gear.

The airplane was powered by a Lycoming IO-320-B1A reciprocating engine on the left wing and a Lycoming LIO-320-B1A reciprocating engine on the right wing, and each was rated at 160 horsepower. The engines had 4 cylinders, 320-cubic-inch displacement, and fuel injection. The right engine had a counter-rotating kit installed. Each engine drove a Hartzell 2-blade, single-acting, hydraulically operated, constant-speed propeller with feathering capability.

The airplane's electrical power was supplied by a 12-volt, direct-current, negative-ground system. The primary electrical source came from two 12-volt, 50-ampere alternators controlled by an overvoltage relay and voltage regulator. The overvoltage relay and voltage regulator were mounted on the aft bulkhead of the nose section. Secondary power was provided by a 12-volt, 35-ampere hour battery that supplies power for starting and was a reserve power source in the event of an alternator failure. The battery was mounted in a battery box located immediately aft of the baggage compartment. The amp/voltmeter instrument was installed in the instrument panel. Alternator isolation switches were mounted on the instrument panel.

According to FAA records, the airplane's charging system was modified on December 8, 1993, by the removal of the generators and installation of an alternator charging system in accordance with Supplement Type Certificate (STC) SA334SW. If both alternators were inoperative, the airplane battery would be the only remaining source of electrical power. If the airplane battery were depleted and electrical power was not available, the Piper Twin Comanche PA-30 Pilot's Operating Handbook (POH) stated that the pilot must land with the flaps in the retracted position and must initiate the manual gear extension procedure and that the final approach landing speed must not exceed 100 mph or 87 knots.

The airplane was also modified with LoPresti front engine cowlings in accordance with STC SA3302SO. The cowling modification would not have permitted a visual examination of the front side of the engine and the alternator belts during a preflight walk-around inspection unless the upper cowling was removed.

The last entry in the airframe maintenance records was on August 20, 2014, when the last annual inspection was accomplished. At that time, the airplane had accumulated a total of 4,769 flight hours. No engine maintenance records were found. The airplane's Hobbs meter was not found in the wreckage. Due to impact damage to the cabin's digital instruments, the tachometer time at the time of the accident could not be determined. METEOROLOGICAL INFORMATIONAt 1054, PAHN, located about 12 miles north of the accident site, reported the following conditions: wind from 150° at 7 knots, 10 miles visibility, clear skies, temperature 11°C, dew point 6°C, and an altimeter setting of 30.23 inches of mercury. AIRPORT INFORMATIONThe airplane, which was manufactured in 1964, was an all-metal multiengine airplane that incorporated a semi-monocoque fuselage and empennage design. The airplane was equipped with fully cantilevered wings, electrically operated wing flaps, and electrically operated retractable tricycle landing gear.

The airplane was powered by a Lycoming IO-320-B1A reciprocating engine on the left wing and a Lycoming LIO-320-B1A reciprocating engine on the right wing, and each was rated at 160 horsepower. The engines had 4 cylinders, 320-cubic-inch displacement, and fuel injection. The right engine had a counter-rotating kit installed. Each engine drove a Hartzell 2-blade, single-acting, hydraulically operated, constant-speed propeller with feathering capability.

The airplane's electrical power was supplied by a 12-volt, direct-current, negative-ground system. The primary electrical source came from two 12-volt, 50-ampere alternators controlled by an overvoltage relay and voltage regulator. The overvoltage relay and voltage regulator were mounted on the aft bulkhead of the nose section. Secondary power was provided by a 12-volt, 35-ampere hour battery that supplies power for starting and was a reserve power source in the event of an alternator failure. The battery was mounted in a battery box located immediately aft of the baggage compartment. The amp/voltmeter instrument was installed in the instrument panel. Alternator isolation switches were mounted on the instrument panel.

According to FAA records, the airplane's charging system was modified on December 8, 1993, by the removal of the generators and installation of an alternator charging system in accordance with Supplement Type Certificate (STC) SA334SW. If both alternators were inoperative, the airplane battery would be the only remaining source of electrical power. If the airplane battery were depleted and electrical power was not available, the Piper Twin Comanche PA-30 Pilot's Operating Handbook (POH) stated that the pilot must land with the flaps in the retracted position and must initiate the manual gear extension procedure and that the final approach landing speed must not exceed 100 mph or 87 knots.

The airplane was also modifie...