WPR11LA113

The pilot reported that after takeoff the right engine lost power as he turned onto the left crosswind leg of the traffic pattern. He continued to turn onto the downwind leg, making sure to keep the airspeed above the single-engine control speed of 90 mph. The pilot’s last recollection was turning to final approach and seeing the runway. A witness in the area reported hearing the sound of an engine popping and backfiring before the airplane started the takeoff roll. The airplane subsequently impacted the roof of a private residence located about 900 feet from the runway threshold. The airplane came to rest inverted in the front yard. The airplane had recently undergone maintenance, which included the overhaul of both engines. The pilot had flown the airplane into the airport the day before and, after landing, called the maintenance facility to report that the right engine was running rough. A mechanic was not available to help him and he was told that he should not fly the airplane. A postaccident examination of both the right and left engines revealed no evidence of mechanical failures or malfunctions that would have precluded normal operation. A global positioning system (GPS) unit was recovered and downloaded. The information indicated that the airplane continued to climb on the downwind leg to pattern altitude and then descended and reduced power to final approach. The last heading was aligned with the runway with a ground speed of 76 miles per hour and 1,400 feet east of the landing threshold. The pilot likely allowed the airspeed to decrease below the single-engine control speed and did not maintain sufficient altitude to clear the house while on final approach.

HISTORY OF FLIGHT On January 30, 2011, about 0720 Pacific standard time (PST), a Piper Twin Comanche, PA-30, N64RJ, lost engine power and impacted a house during landing at Big Bear City Airport (L35), Big Bear City, California. Tower General Contractors, Inc., was operating the airplane under the provisions of 14 Code of Federal Regulations (CFR) Part 91. The certificated private pilot sustained serious injuries; the airplane sustained substantial damage. The cross-country personal flight departed L35 about 0715, with a planned destination of Pacoima, California. Visual meteorological conditions prevailed, and no flight plan had been filed. The pilot reported that after takeoff and turning to left crosswind, the right engine lost power. He continued the left turn to downwind and made sure to keep the airspeed above the single engine control speed of 90 miles per hour. The pilot's last recollection of the flight was turning to base leg, and then final approach and seeing the runway. While on final, the airplane impacted the roof of a house, and came to rest in the front yard. A witness who lived north/northeast of the airport, and familiar with the sounds associated with the Big Bear airport, reported that she was at home working on her computer when she heard an airplane with very loud engines, which she attributed to it being a twin engine airplane. She noted that the engine was popping and backfiring; this went on for a solid 2 minutes, and then she heard the airplane start to takeoff down runway 26. She noted that the engine sounds and the backfiring were waning as the airplane got farther away. She was very surprised that the pilot would attempt to takeoff with the engine sounding as it did. AIRCRAFT INFORMATION The airplane was a Piper Twin Comanche PA-30, serial number 30-1931. A review of the airplane’s logbooks revealed that the airplane had a total airframe time of 2,156 hours at the last annual inspection. The logbooks contained an entry for an annual inspection dated January 8, 2011. The tachometer read 2,156.0 hours at the last inspection. The tachometer read 2,167.4 hours at the accident scene. The left engine was a Lycoming IO-320 C1A, serial number L-4301-55A. Total time recorded on the engine at the last annual inspection was 2,147.0 hours, and time since major overhaul was 0.0 hours. The total time on the engine at the time of the accident was 2,167.4 hours. The right engine was a Lycoming IO-320 C1A, serial number L-4277-55A. Total time recorded on the engine at the last annual inspection was 2,147.0 hours, and time since major overhaul was 0.0 hours. The total time on the engine at the time of the accident was 2,165.9 hours. A review of the airplane records revealed that the owner had both the left and right engines recently overhauled, and was having issues with the right engine running rough. The pilot flew the airplane from Lancaster, California, to Big Bear Airport on January 29, 2011. After landing, the pilot called theowner of Exodus Air Service (EAS) around 1100, and told him that the right engine was still running rough. The owner asked him to find a mechanic, but was told that there were no mechanics available. The pilot was trying to obtain information about the magneto “P” leads and how to identify them. The owner of EAS told him to make sure they were tight, and to run the engine to see if it would produce full power. He told the pilot if it did not produce full power to not fly the airplane. The owner of EAS did not hear from the pilot until after 1700. The pilot related that he had not run the engine, because he had gone skiing. The owner of Exodus had no further communications with the pilot, and did not know about the accident until the next evening when he saw it on the news. WRECKAGE AND IMPACT INFORMATION The accident site was located two houses southeast of the intersection of East Mountain View Boulevard and Mount Doble Drive. The airplane impacted the roof of a private residence, and came to rest inverted in the front yard. The accident site was located 900 feet east of the landing threshold of runway 26. The extended centerline of runway 26 was 130 feet south of the impact site. The airplane was recovered from the accident site, and transported to Aircraft Recovery Service for further examination. TESTS AND RESEARCH Investigators examined the wreckage at Aircraft Recovery Service, Littlerock, California, on February 2, 2011. The airframe and engine were examined with no major mechanical anomalies identified that would have precluded normal operations. The right magneto on the right engine was run on a test stand and appeared to function normally; however, it was noted that the magneto was making noise consistent with some anomaly with an internal bearing. Both the left and right magnetos for the right engine were sent to the manufacturer for further examination. A Garmin GPSMAP 696 portable GPS unit was recovered from the accident airplane. It was a battery-powered portable multi function display and GPS receiver with a 7-inch diagonal high resolution LCD display screen. The GPS unit sustained major impact damage. The unit was shipped to the National Transportation Safety Board Vehicle Recorder Lab for download of data. A factual report was submitted and is attached to the docket. The recovered data from the GPS showed on the accident date that starting at 0706 PST the airplane was moved from the ramp area towards the run-up area for runway 26. At 0712, the ground speed increased as it traveled down the runway. The data showed the accident airplane traveling in a left closed pattern attaining an altitude of just over 8,000 feet (field elevation is 6,752 feet) while in the pattern and then descending while on final approach at 0717; the last recorded GPS waypoint was on a heading of 266 degrees with a ground speed of 76 miles per hour at 6,901 feet. The last recorded waypoint was 1,400 feet east of the landing threshold for runway 26. TeledyneContinental Motors (TCM) personnel examined the magnetos under the supervision of a Safety Board investigator at the factory in Mobile, Alabama, on March 2, 2011. TCM submitted a written report, and the Safety Board investigator who observed the inspection concurred with the facts in the report. No abnormalities with either magneto were found that would have precluded normal operations.