- Date
- December 31, 2005, 08:00 local (16:00 UTC)
- Place
- Valley Center, CA
- Injuries
- 3 fatal
- Damage
- Destroyed
- Phase of flight
- Initial climb
- Aircraft
- N7944RBeech V35A
- Weather
- Instrument (IMC) · Day
- Status
- Completed · report August 30, 2007
- Report
- Approved by Office Director
- Parties
- Federal Aviation Administration, Teledyne Continental Motors, Raytheon Aircraft Company
- FAA report
- 20051231033189A
- Case key
- 63026
From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.
On this page
Probable cause
the pilot's failure to maintain an adequate airspeed margin following a loss of engine power in the takeoff initial climb, resulting in a stall/spin. While the laboratory tests indicated the presence of an unknown biological contaminant in the fuel manifold valve, the amount of contamination could not be established and thus the underlying reason for the loss of engine power was not determined.
Sequence of events
NTSB’s coding before 2008: each occurrence and phase of flight, and the causes and factors under it. The codes are defined in NTSB’s coding manual.
Analysis
The airplane collided with terrain following a loss of control during the takeoff/initial climb. This airplane was the last of five airplanes that were traveling to another airport for the group's overnight trip. Witnesses heard a loud bang as the airplane reached about 800 feet above ground level (agl). They observed the airplane roll once or twice as the nose went down. The airplane came to rest with the tail in an avocado tree and was largely consumed by fire. Investigators could not establish control continuity due to the extensive mechanical and thermal damage. Investigators disassembled the fuel manifold valve. The screen, interior, and the line going to the pressure gauge had a thin coating of a viscous amber substance that had a strong, foul odor. The most likely source of the residue appeared to be biological contamination of the fuel, based on the major peaks in the gas chromatography with a mass spectrometer detector (GC/MS) spectra for the fatty acids and fatty nitriles having even numbers of carbon atoms. None of the additives or sealants approved by Teledyne Continental Motors appeared in the GC/MS identification, and it did not appear that the compounds identified in the spectra could be simple breakdown or combustion products of the approved additives or sealants. The substance did not clog the valve or screen. The fuel nozzles were open. Investigators found no anomalies that would have prevented normal operation or production of rated power.
Factual narrative
History of flight
On December 31, 2005, about 0800 Pacific standard time, a Beech V35A, N7944R, collided with terrain following a loss of control during the takeoff/initial climb near Valley Center, California. The private pilot/owner was operating the airplane under the provisions of 14 CFR Part 91. The pilot and two passengers sustained fatal injuries; the airplane was destroyed. The personal cross-country flight was departing from Blackington Airpark, a private airfield, with a planned destination of Borrego Springs, California. Visual meteorological conditions prevailed, and no flight plan had been filed. The approximate global positioning system (GPS) coordinates of the primary wreckage were 33 degrees 15 minutes north latitude and 117 degrees 06 minutes west longitude.
The pilot's airplane was the last of five airplanes that were traveling to another airport for an overnight trip. Witnesses observed the takeoff, and reported that they heard a loud bang as the airplane reached about 800 feet above ground level (agl). They observed the airplane roll once or twice as the nose went down.
The airplane came to rest with the tail in an avocado tree.
Personnel information
A review of Federal Aviation Administration (FAA) airman records revealed that the pilot held a private pilot certificate with ratings for airplane single engine land and multiengine land. The pilot held a third-class medical certificate issued on September 1, 2004. It had no limitations or waivers.
An examination of the pilot's logbook revealed no entries after 1999. FAA records showed that the pilot reported a total flight time of 2,875 hours on his application for his medical certificate.
Aircraft information
The airplane was a Beech V35A, serial number D-8961. A review of the airplane's logbooks revealed that the airplane had a total airframe time of 4,233 hours at the last annual inspection on March 1, 2005. The tachometer read 979.04 at the last inspection.
The engine was a Teledyne Continental Motors TSIO-520-D, serial number 156128-8-D. It had 979 hours since major overhaul at the annual.
Airport information
The Airport/ Facility Directory, Southwest U. S., indicated that runway 17 was 2,200 feet long and 50 feet wide. The runway surface was asphalt. All landings were on runway 35 and all takeoffs were on runway 17. The runway sloped uphill to the north.
Wreckage and impact information
The FAA accident coordinator examined the wreckage at the accident scene. He reported that the airplane came to rest at the edge of a driveway with the forward portion of the empennage hanging down vertically from branches of an avocado tree.
The propeller separated and was partially buried; it was not charred.
The orientation of the fuselage was 360 degrees.
Medical and pathological information
The San Diego County Coroner completed an autopsy.
Tests and research
The FAA, Raytheon Aircraft Company, and Teledyne Continental Motors (TCM) were parties to the investigation.
Investigators examined the wreckage at Eastman Aircraft, Corona, California, on January 4, 2006.
The left side of the airframe sustained more fire damage than the right side. Most of the cabin, left wing, fuselage, and inboard half of the right wing were not distinguishable within the wreckage. The left ruddervator was charred, and a few feet of the inboard leading edge was missing. The inboard and forward third of both the top and bottom of the right ruddervator was discolored, and exhibited some wrinkles and tears.
The recovery agent cut all of the empennage control cables during recovery. Investigators established control continuity from the right aileron to the wing root. They found several sections of unidentified cable. They could not identify any control cables for the left aileron. The control cables remained attached to the elevator portion of the control column. Cables remained attached to the forward rudder bellcrank. Cables remained connected to the ruddervators and the elevator trim tabs. All identifiable cable pieces that were not cut during recovery were broomstrawed.
Investigators removed the engine. They slung it from a hoist, and removed the top spark plugs. All spark plugs were clean and circular with no mechanical deformation except for the lower No 1. The spark plug electrodes were gray.
Investigators manually rotated the crankshaft. The crankshaft rotated freely, and the valves moved approximately the same amount of lift in firing order. The gears in the accessory case turned freely. Investigators obtained thumb compression on all cylinders in firing order.
A borescope inspection revealed no mechanical deformation on the valves, cylinder walls, or internal cylinder head. The piston heads and valve heads had light deposits.
The oil pump had light scratches in the cavity. The gear teeth showed some wear.
Investigators rotated both magnetos manually. The left magnet separated from the engine, and had exterior mechanical damage. It did not sound like the right magneto when rotated, and produced no spark at any terminal. Disassembly revealed that the interior was moist. After drying the inside, the magneto sparked on all terminals. The right magneto remained attached to the engine, and produced spark on all terminals.
There were two vacuum pumps. One vacuum pump separated and burned. The other vacuum pump drive gear remained unbroken, but the vacuum pump would not turn.
The cover for the fuel selector valve was mechanically damaged, and the cutout was elongated to the 2-oclock position. The selector indicated between positions. Investigators removed the cover and noted that the selector was in a detent. They turned the selector, and it moved freely between the detents. They connected a hose to the line and blew through the hose after selecting all of the different positions. Air flowed freely with no leaks except for the off position. A review of a schematic of the fuel system determined that the selector was to the auxiliary position.
The oil sump screen was clean. Investigators peeled half of the oil filter open, and that section was clean.
The engine driven fuel pump drive gear was undamaged, and the pump rotated freely. When submerged in a fluid and rotated with a drill, it pumped the fluid.
Investigators disassembled the fuel manifold valve. The screen, interior, and the line going to the pressure gauge had a thin coating of a viscous amber substance that had a strong, foul odor. The substance did not clog the valve or screen. The fuel nozzles were open.
The turbocharger wastegate was open, and the compressor and turbine turned freely. The TCM representative moved the wastegate valve assembly by hand and felt resistance from the springs.
The airframe manufacturer's representative determined that the landing gear were up. The flap actuator split apart. The elevator trim measured 0.090 inches; the representative determined that this equated to 0-5 degrees tab up.
The spinner was crushed aft, and did not exhibit rotational scoring. One blade remained straight, and did not have any scratches or gouges. The other two blades bent aft and were loose in the hub. One of these blades had a 3/8-inch nick on the cambered side about 6 inches from the tip. The third blade did not have any gouges or scrape marks.
Additional information
A specialist in the Safety Board's Materials Laboratory examined the viscous amber substance in the fuel manifold valve. The complete report is part of the public docket. Pertinent parts of the report follow.
The specialist investigated the elemental composition of a sample of the residue by using X-ray energy dispersive spectroscopy in the scanning electron microscope. A representative spectrum indicated major peaks for carbon, sulfur, and chlorine, with smaller peaks for aluminum and silicon.
The specialist s
Aircraft
- Registration
- N7944R
- Reported as
- Beech V35A
- Category
- Airplane
- Serial number
- D-8961
- Airframe hours
- 4,233
- Engine
- Continental TSIO-520-D, 285 horsepower, reciprocating
- Damage
- Destroyed
- Fire
- On-Ground
- Flight
- Personal · Part 91
- Registered owner
- Lance N. Teren
- Last inspection
- Annual · March 1, 2006
- Departed
- 2CA4 · Valley Center, CA
- Destination
- L08 · Borrego Springs, CA
- Airport
- 2CA4 · Blackington Airpark, runway 17, 2,200 × 50 ft, asphalt
Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.
Flight crew
As NTSB recorded them. NTSB leaves out names.
- Role
- Pilot
- Age
- 45
- Injuries
- Fatal
- Certificate
- Private
- Airplane ratings
- Multi-engine land, Single-engine land
- Medical
- Class 3
- Seat
- Left
- Flight hours
- 2,875 total
Weather
- Conditions
- Instrument (IMC) · Day
- Wind
- Calm
- Visibility
- 4 statute miles
- Lowest ceiling
- 1,000 ft broken
- Temperature
- 46 °F, dew point 45 °F
- Altimeter
- 29.98 inHg
- Observed at
- OKB
Docket · 14
The files NTSB released with the investigation on August 4, 2007, on NTSB’s docket system: statements, records, photos and specialists’ reports. 15.5 MB in all.
FAA reports on this event · 1
The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.