Friday, June 01, 2012

Beech King Air 200, N849BM: Accident occurred March 16, 2011 in Long Beach, California

NTSB Identification: WPR11FA166 
14 CFR Part 91: General Aviation
Accident occurred Wednesday, March 16, 2011 in Long Beach, CA
Probable Cause Approval Date: 08/29/2012
Aircraft: BEECH 200, registration: N849BM
Injuries: 5 Fatal,1 Serious.


Witnesses reported that the airplane’s takeoff ground roll appeared to be normal. Shortly after the airplane lifted off, it stopped climbing and yawed to the left. Several witnesses heard abnormal sounds, which they attributed to propeller blade angle changes. The airplane’s flight path deteriorated to a left skid and its airspeed began to slow. The airplane’s left bank angle increased to between 45 and 90 degrees, and its nose dropped to a nearly vertical attitude. Just before impact, the airplane’s bank angle and pitch began to flatten out. The airplane had turned left about 100 degrees when it impacted the ground about 1,500 feet from the midpoint of the 10,000-foot runway. A fire then erupted, which consumed the fuselage.

Review of a security camera video of the takeoff revealed that the airplane was near the midpoint of the runway, about 140 feet above the ground, and at a groundspeed of about 130 knots when it began to yaw left. The left yaw coincided with the appearance, behind the airplane, of a dark grayish area that appeared to be smoke. A witness, who was an aviation mechanic with extensive experience working on airplanes of the same make and model as the accident airplane, reported hearing two loud “pops” about the time the smoke appeared, which he believed were generated by one of the engines intermittently relighting and extinguishing.

Postaccident examination of the airframe, the engines, and the propellers did not identify any anomalies that would have precluded normal operation. Both engines and propellers sustained nearly symmetrical damage, indicating that the two engines were operating at similar low- to mid-range power settings at impact. The airplane’s fuel system was comprised of two separate fuel systems (one for each engine) that consisted of multiple wing fuel tanks feeding into a nacelle tank and then to the engine. The left and right nacelle tanks were breached during the impact sequence and no fuel was found in either tank. Samples taken from the fuel truck, which supplied the airplane's fuel, tested negative for contamination. However, a fuels research engineer with the United States Air Force Fuels Engineering Research Laboratory stated that water contamination can result from condensation in the air cavity above a partially full fuel tank. Both diurnal temperature variations and the atmospheric pressure variations experienced with normal flight cycles can contribute to this type of condensation. He stated that the simplest preventive action is to drain the airplane’s fuel tank sumps before every flight.

There were six fuel drains on each wing that the Pilot’s Operating Handbook (POH) for the airplane dictated should be drained before every flight. The investigation revealed that the pilot’s previous employer, where he had acquired most of his King Air 200 flight experience, did not have its pilots drain the fuel tank sumps before every flight. Instead, maintenance personnel drained the sumps at some unknown interval. No witnesses were identified who observed the pilot conduct the preflight inspection of the airplane before the accident flight, and it could not be determined whether the pilot had drained the airplane’s fuel tank sumps. He had been the only pilot of the airplane for its previous 40 flights. Because the airplane was not on a Part 135 certificate or a continuous maintenance program, it is unlikely that a mechanic was routinely draining the airplane's fuel sumps.

The witness observations, video evidence, and the postaccident examination indicated that the left engine experienced a momentary power interruption during the takeoff initial climb, which was consistent with a power interruption resulting from water contamination of the left engine's fuel supply. It is likely that, during the takeoff rotation and initial climb, water present in the bottom of the left nacelle tank was drawn into the left engine. When the water flowed through the engine's fuel nozzles into the burner can, it momentarily extinguished the engine’s fire. The engine then stopped producing power, and its propeller changed pitch, resulting in the propeller noises heard by witnesses. Subsequently, a mixture of water and fuel reached the nozzles and the engine intermittently relighted and extinguished, which produced the grayish smoke observed in the video and the “pop” noises heard by the mechanic witness. Finally, uncontaminated fuel flow was reestablished, and the engine resumed normal operation.

About 5 months before the accident, the pilot successfully completed a 14 Code of Federal Regulations Part 135 pilot-in-command check flight in a King Air 90. However, no documentation was found indicating that he had ever received training in a full-motion King Air simulator. Although simulator training was not required, if the pilot had received this type of training, it is likely that he would have been better prepared to maintain directional control in response to the left yaw from asymmetrical power. Given that the airplane’s airspeed was more than 40 knots above the minimum control speed of 86 knots when the left yaw began, the pilot should have been able to maintain directional control during the momentary power interruption.

Although the airplane’s estimated weight at the time of the accident was about 650 pounds over the maximum allowable gross takeoff weight of 12,500 pounds, the investigation determined that the additional weight would not have precluded the pilot from maintaining directional control of the airplane.

The National Transportation Safety Board determines the probable cause(s) of this accident as follows:
The pilot’s failure to maintain directional control of the airplane during a momentary interruption of power from the left engine during the initial takeoff climb. Contributing to the accident was the power interruption due to water contamination of the fuel, which was likely not drained from the fuel tanks by the pilot during preflight inspection as required in the POH.



A twin-engine plane that crashed shortly after takeoff in Long Beach last year, killing several prominent community members, was 653 pounds overweight and might have had water in its fuel tanks, according to National Transportation Safety Board records.

Prominent Long Beach community and business leaders, including real estate broker and cycling activist Mark Bixby, 44, a descendant of one of the city’s founding families, were among the five killed in the fiery crash of the Beech King 200 as it took off from Long Beach Airport for a Utah ski trip in March 2011.

Also killed were real estate investor Thomas Dean, 50; his business partner Jeffrey Berger, 49; Bruce Krall, 51; and the pilot, Kenneth Cruz, 43. Another passenger, Mike Jensen, then 51, survived.

The NTSB has not cited a cause for the crash and its investigation is continuing.

But an NTSB History of Flight,” first reported on by the Belmont Shore-Naples Patch website, details the nine-second flight and the circumstances surrounding the crash.

According to the chronology and other records in the NTSB’s online investigation file, the plane’s wings wobbled as it started to climb, then banked sharply to the left and nosedived into the ground.

 Several witnesses told investigators that they heard what sounded like engine trouble.

The maintenance director at an aviation company that serviced the plane, which was owned by Dean, told investigators he heard two “pops” shortly after its wheels left the runway.

He said he believed the noises were related to the engines being extinguished by water in fuel tank sumps that should be drained by the pilot before every flight. 

“He didn’t believe that the accident airplane’s fuel tanks had been regularly drained since the owner bought it in the summer of 2009,” according to the NTSB’s interview of the maintenance director.

If not drained, a “slug” of water would flow to the plane’s 14 fuel nozzles, shutting the engines down momentarily, followed by a surge of fuel that could be reignited automatically, the report states.

“The [maintenance director] believes the two pops he heard were attempts by the engine to relight the reintroduced fuel,” the NTSB flight history stated.

The plane appeared to pull up somewhat just before the crash, records show, indicating that the engines might have restarted but too late to keep it flying.

After the crash, investigators calculated the craft's weight from the amount of fuel, number of passengers and pieces of baggage it carried.

“The airplane was estimated to be approximately 653 pounds overweight at takeoff,” the flight history said.



NTSB Identification: WPR11FA166
14 CFR Part 91: General Aviation
Accident occurred Wednesday, March 16, 2011 in Long Beach, CA
Aircraft: BEECH 200, registration: N849BM
Injuries: 5 Fatal,1 Serious.
HISTORY OF FLIGHT

On March 16, 2011, at 1029 Pacific daylight time, a Beech Super King Air 200, N849BM, impacted terrain following a loss of control during takeoff from Long Beach Airport, Long Beach, California. The commercial pilot and four passengers were fatally injured; a fifth passenger was seriously injured. The airplane was substantially damaged. The airplane was being operated by Carde Equipment Sales LLC under the provisions of 14 Code of Federal Regulations Part 91. An instrument flight rules (IFR) flight plan had been filed for a cross-country flight to Salt Lake City, Utah, and the crash occurred on initial departure. Visual meteorological conditions prevailed at the time of the accident.

Full narrative available

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