History of Flight
On December 19, 2008, about 1141 Hawaiian standard time, a Piper PA-28-140, registration N6182J, collided with trees and a power line during a forced landing following a partial loss of engine power on takeoff initial climb from Kalaeloa Airport, Kapolei, Hawaii. The flight instructor, the private pilot receiving instruction, and the passenger were seriously injured. The airplane was operated by Offshore Flight School, Inc., under 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed, and no flight plan was filed for the instructional flight, which originated from Honolulu International Airport about 1020.
The flight instructor stated that the flight was a complementary pleasure flight for the flight school owner’s friend and his wife. The plan was a counterclockwise trip around Oahu with touch-and-go landings at Dillingham Airport and Kalaeloa Airport. The private pilot occupied the left front seat, and the instructor the right front seat.
The flight to Dillingham Airport and landing were uneventful. Shortly after departing Dillingham, about 1120, the instructor had the private pilot change the fuel selector from left to right tank. About 1135, while 4 miles west of Kahe power plant, the instructor contacted Kalaeloa tower for landing clearance and received clearance for the option to runway 4L. The airplane was level at 1,500 feet mean sea level when she had the private pilot reduce power and glide toward the runway. Carburetor heat was not used, nor was the engine cleared during the glide. The instructor was uncertain of the throttle setting during descent.
The private pilot landed the airplane and, while still rolling, advanced the throttle for takeoff. Immediately after liftoff, the instructor noted the engine was not accelerating above 2,100 rpm. She took control, checked engine instruments, fuel tank selector, fuel pressure, and confirmed throttle and mixture controls were full forward. She called the tower and initiated a left turn back toward the runway, away from terrain covered with bushes. The instructor estimated a maximum height of about 200 feet above ground level. She did not recall the impact sequence but believed the airplane hit a power line.
Personnel Information
The flight instructor, age 40, held a commercial pilot certificate with single-engine land and instrument ratings, and a flight instructor certificate for single-engine land issued on November 4, 2008. Her most recent second-class FAA medical certificate was issued on April 23, 2008, with a requirement to wear corrective lenses. She reported about 465 flight hours, with 70 hours in the same make and model, and about 17 hours of flight instruction given.
The private pilot, age 59, held a private pilot certificate with single-engine land rating. His most recent third-class medical certificate was issued on January 5, 1998, and was not current.
Aircraft Information
The airplane was a single-engine, propeller-driven, four-seat Piper PA-28-140 manufactured in 1976, equipped with dual flight controls. It was powered by a Lycoming O-320-E3D reciprocating engine rated at 150 horsepower. The most recent annual inspection was completed on April 19, 2008, at a tachometer reading of 3,702.24 hours, and a 100-hour inspection on November 9, 2008, at 3,802.24 hours. The engine had accumulated 1,823.6 hours since major overhaul at the 100-hour inspection. The tachometer read 3,823.24 hours at the accident. Maintenance records showed no uncorrected discrepancies.
The Pilot’s Operating Manual states that carburetor heat should not be applied during approach unless carburetor icing is indicated, as it reduces power. The Emergency Procedures section notes that engine roughness is usually due to carburetor icing, indicated by a drop in rpm, and requires prompt action including turning carburetor heat on.
Meteorological Information
At 1153, weather conditions at Kalaeloa Airport were: wind 130 degrees at 8 knots, visibility 10 statute miles, scattered clouds at 2,200 feet, temperature 77°F, dew point 70°F, altimeter 30.05 inches of Mercury. These conditions, plotted on a carburetor icing probability chart, indicated serious icing at glide power. Calculated relative humidity was 79 percent.
Wreckage and Impact Information
FAA inspectors reported that the airplane impacted trees and a power line before sliding across a road and coming to rest. The impact heading was about 135 degrees magnetic. No fire occurred. The fuselage with the right wing folded back came to rest on its left side on the west side of the road. The right wing exhibited impact damage along the full leading edge, with heavier damage at the tip and fuel tank, which was ruptured and crushed aft to the spar. The empennage was intact with no visible damage to the vertical stabilizer and rudder. The horizontal stabilator was secure but had impact damage.
The left wing separated from the fuselage and was found on the east side of the road, with leading edge damage outboard of the fuel tank and near the tip. The left fuel tank was intact and contained about 16 gallons of blue fuel.
The fuel tank selector valve was found near the right tank position. The carburetor heat control was in the off position. The throttle was closed, and the mixture control was about halfway between full rich and idle cutoff. A first responder reported moving a red handle, likely the mixture control, aft.
On January 21, 2009, under NTSB supervision, the wreckage was examined by a representative of the airframe manufacturer. Control continuity was verified for all flight controls, except for impact and recovery-related separations to the aileron control cables. The fuel tank selector valve, previously removed, revealed that the fuel valve inner fitting was slightly out of the detent for the right fuel tank position, offering about 80 percent of normal opening for fuel flow.
The propeller remained on the engine and was removed after recovery. Both blades were bent aft, one with 'S' bending, and showed leading edge damage and chordwise scratches consistent with rotation at impact.
The engine crankshaft was rotated by hand, and compression, suction, and valve train continuity were verified to all cylinders. Borescope examination revealed no anomalies. Magnetos produced spark on all towers when rotated. The engine-driven fuel pump operated normally. The carburetor, partially broken, was disassembled with no anomalies. Filters for the electric fuel pump and gascolator were clear, as were fuel tank finger strainers and all fuel lines. No engine anomalies were noted.
Additional Information
An article on induction icing by the engine manufacturer notes that carburetor ice can form under moist conditions with relative humidity of 50 to 60 percent and outside air temperatures from 20 to 90°F. It recommends using full carburetor heat when operating at low power for instrument approaches or traffic pattern flight.
The FAA Pilot’s Handbook of Aeronautical Knowledge recommends applying full carburetor heat before closing the throttle if carburetor icing is suspected, and periodically opening the throttle to keep the engine warm.