CEN15FA034

The pilot's failure to maintain lateral control of the airplane after a reduction in left engine power and his application of inappropriate rudder input. Contributing to the accident was the pilot's failure to follow the emergency procedures for an engine failure during takeoff. Also contributing to the accident was the left engine power reduction for reasons that could not be determined because a postaccident examination did not reveal any anomalies that would have precluded normal operation and thermal damage precluded a complete examination.

The airline transport pilot was departing for a repositioning flight. During the initial climb, the pilot declared an emergency and stated that the airplane "lost the left engine." The airplane climbed to about 120 ft above ground level, and witnesses reported seeing it in a left turn with the landing gear extended. The airplane continued turning left and descended into a building on the airfield. A postimpact fired ensued and consumed a majority of the airplane. Postaccident examinations of the airplane, engines, and propellers did not reveal any anomalies that would have precluded normal operation. Neither propeller was feathered before impact. Both engines exhibited multiple internal damage signatures consistent with engine operation at impact. Engine performance calculations using the preimpact propeller blade angles (derived from witness marks on the preload plates) and sound spectrum analysis revealed that the left engine was likely producing low to moderate power and that the right engine was likely producing moderate to high power when the airplane struck the building. A sudden, uncommanded engine power loss without flameout can result from a fuel control unit failure or a loose compressor discharge pressure (P3) line; thermal damage prevented a full assessment of the fuel control units and P3 lines. Although the left engine was producing some power at the time of the accident, the investigation could not rule out the possibility that a sudden left engine power loss, consistent with the pilot's report, occurred. A sideslip thrust and rudder study determined that, during the last second of the flight, the airplane had a nose-left sideslip angle of 29°. It is likely that the pilot applied substantial left rudder input at the end of the flight. Because the airplane's rudder boost system was destroyed, the investigation could not determine if the system was on or working properly during the accident flight. Based on the available evidence, it is likely that the pilot failed to maintain lateral control of the airplane after he reported a problem with the left engine. The evidence also indicates that the pilot did not follow the emergency procedures for an engine failure during takeoff, which included retracting the landing gear and feathering the propeller. Although the pilot had a history of anxiety and depression, which he was treating with medication that he had not reported to the Federal Aviation Administration, analysis of the pilot's autopsy and medical records found no evidence suggesting that either his medical conditions or the drugs he was taking to treat them contributed to his inability to safely control the airplane in an emergency situation.

Cockpit Voice Recorder The airplane was equipped with a Fairchild Model A100S cockpit voice recorder (CVR). The unit was removed from the wreckage and sent to the National Transportation Safety Board (NTSB) Vehicle Recorder Laboratory for download. A timeline generated from the CVR recording determined that the time duration from liftoff to building impact was about 26 seconds. Nonvolatile Memory The airplane was equipped with a Sandel ST3400 terrain awareness and warning system and radio magnetic indicator unit. This unit was retained and examined by the NTSB Vehicle Recorder Laboratory. The examination revealed that the unit sustained severe thermal damage and that the nonvolatile memory contents were destroyed; therefore, no data were available for recovery. The following is a chronological summary of the communications between the accident pilot and the ICT air traffic controllers. 0938 The pilot requested an IFR clearance to MEZ. Clearance Delivery read the clearance to the pilot, and the pilot read back the clearance correctly. 0940 The pilot requested taxi clearance with the automatic terminal information service (ATIS). Ground Control issued a taxi clearance to runway 1R at Echo 3 intersection via taxiways Alpha 5, Alpha, Bravo, Echo. The pilot read back the instructions correctly. 0941 Ground Control reverified that the accident pilot had ATIS Hotel. 0942 The pilot advised he had to perform a quick run-up and asked Ground Control for a location to complete the run-up. Ground Control advised him to proceed to the end of the taxiway or to the Echo 3 intersection. 0947 The pilot requested and was cleared for takeoff by Local Control on runway heading. The pilot read back the instructions correctly. 0948 The pilot declared an emergency and advised that he "lost the left engine." Airport Surveillance Video Data Airport surveillance videos, which captured the last 9 seconds of the flight, including an image of the airplane within 1 second of impact, was used to estimate the airplane's trajectory and speed. The estimations indicated that the airplane's groundspeed increased from 85 to 92 knots and that the descent rate increased from about 0 to 1,600 ft per minute just before impact. The airplane's altitude reached a maximum of about 120 ft agl before it descended into the building. Sideslip Thrust and Rudder Study The NTSB conducted a sideslip thrust and rudder study based on information from the surveillance videos. This study evaluated the relationships between the airplane's sideslip angle, thrust differential, and rudder deflection. Calculations made using multiple rudder deflection angles showed that full right rudder deflection would have resulted in a sideslip angle near 0°, a neutral rudder would have resulted in an airplane sideslip angle between 14° and 19°, and a full left rudder deflection would have resulted in an airplane sideslip angle between 28° and 35° airplane nose left. Calculation of the airplane's sideslip angle as captured in the image of the airplane during the last second of flight showed that the airplane had a 29° nose-left sideslip, which would have required the application of a substantial left rudder input. CVR Sound Spectrum Analysis A sound spectrum analysis was completed using harmonic signatures recorded on the CVR from the cockpit area microphone and an unconnected microphone jack. A graph of the harmonic signatures from the cockpit area microphone show signatures that likely represent the propeller blade tip sounds and propeller rpm diverging, consistent with one propeller rpm decreasing. A graph of harmonic signatures from the unconnected microphone jack revealed electrical noise signatures generated from the engines. At the beginning of the graph, these signatures (two for each engine) increased, corresponding to increasing engine rpm. Later, two of the signatures began to decrease, consistent with one engine's rpm decreasing. This 53-year-old pilot had been an air traffic controller for more than 20 years at ICT and retired in 2013. Since his first medical certification in 1980, the pilot had reported thyroid disease, hernias, and recurrent symptomatic kidney stones to the FAA. Beginning in 1997, he had episodes of anxiety and depression, which required intermittent treatment with medication. During the first episode, he was unable to work for a certain time. A second episode began in October 2013 and continued through the accident date. He did not report his recurrent anxiety or his use of buspirone and escitalopram to the FAA. However, he visited his primary care physician about 1 month before the accident and was noted to be stable on the medications. In addition, the pilot had a procedure to treat kidney stones in 2013 that he did not report to the FAA. On November 3, 2014, the Regional Forensic Science Center, Sedgwick County, Kansas, performed an autopsy on the pilot. The cause of death was determined to be thermal injuries and smoke inhalation and the manner of death was determined to be an accident. According to the autopsy report, a thin plastic medical catheter was identified in the pilot's pelvis, but it was not further described in the report. The Regional Forensic Science Center also conducted toxicology testing of the pilot's heart blood, which identified carboxyhemoglobin at 39 percent, but no other tested for substances were found. Toxicology testing performed by the Bioaeronautical Research Laboratory at the FAA's Civil Aerospace Medical Institute identified buspirone and citalopram and its metabolite n-desmethylcitalopram in the pilot's heart blood and urine. In addition, the carboxyhemoglobin was 35 percent; no ethanol, cyanide, or any other tested for substances were identified. Buspirone, also named BuSpar, is an anxiolytic prescription medication. Buspirone is different from other anxiolytics in that it has little, if any, typical anti-anxiety side effects, such as sedation and physical impairment, but it does carry a warning, "May impair mental and/or physical ability required for the performance of potentially hazardous tasks (e.g., driving, operating heavy machinery)." Citalopram is a prescription antidepressant, also named Celexa, which carries a warning, "May impair mental and/or physical ability required for the performance of potentially hazardous tasks (e.g., driving, operating heavy machinery)." General The accident site was located at latitude 37° 39.592 N, longitude 97° 25.490 W, at an elevation of 1,363 ft mean sea level. The airplane struck the northeast corner of the FSI building, which housed several flight simulators. A large simulator room on the north end was the point of impact and sustained most of the structural and fire damage. The simulator room was about two stories high, about 198 ft long (east-west), and about 42 ft deep (north-south). Most of the airplane wreckage was distributed from the northeast corner toward the southwest corner of the room and remained on the roof of the simulator room and the attached buildings. A postimpact fired ensued and consumed a majority of the airplane. The left engine, propeller, and left main landing gear were found just inside the building on the ground level. A majority of the left outboard wing, flap, and aileron were found at the foot of the building's exterior east wall. The fuselage, tail section, cockpit, right engine, and right main landing gear were located on the conjoined buildings' rooftops. The cockpit, instrument panels, right engine, and right landing gear strut were located about 160 ft from the initial impact point to the south on the roof of the simulator room. The right engine and propeller came to rest next to the cockpit. The cabin area of the fuselage and empennage came to rest inverted on the lower, west roof. The cabin area was mostly consumed by the postimpact fire. P