LAX03FA051
LAX03FA051

HISTORY OF FLIGHT

On December 16, 2002, about 1430 Pacific standard time (PST), a Piper PA-24-250, N6268P, collided with terrain and several homes in Anaheim Hills, California, following the in-flight separation of the left wing and portions of the horizontal stabilizers. The private pilot/owner was operating the airplane under the provisions of 14 CFR Part 91. The pilot and one passenger sustained fatal injuries; the airplane was destroyed. The personal cross-country flight departed Prescott (PRC), Arizona, at 1129 PST, en route to John Wayne/Orange County Airport (SNA), California. Instrument meteorological conditions prevailed at Orange County. An instrument flight rules (IFR) flight plan had been filed in flight near Palm Springs, California. The primary wreckage was at 33 degrees 50 minutes north latitude and 117 degrees 46 minutes west longitude.

A ground witness reported that he heard an airplane coming down. He looked up and saw the airplane with the wings vertical. He said that the engine was producing power. He saw the airplane hit the ground and skid into the house. He ran across the street to try and assist the occupants. He heard a hissing sound, and then the garage and airplane exploded.

The National Transportation Safety Board investigator-in-charge (IIC) reviewed a transcript of recorded radio transmissions. The airplane departed Prescott, and the pilot obtained flight following from Albuquerque Air Route Traffic Control Center (ARTCC) for the initial part of the trip. The pilot told them that he was level at 10,500 feet. His route of flight would be direct Parker, California; direct Thermal, California; and then direct Santa Ana.

Albuquerque passed control to Los Angeles ARTCC (ZLA) at 1207 PST. At 1216, the pilot advised ZLA that he might need an instrument approach into Orange County, and the controller said that he would keep the pilot advised of the weather. At 1219, ZLA gave the Orange County weather: wind 170 degrees at 12 knots; visibility 10; and few clouds at 2,500 feet, broken layers at 4,000 feet and 20,000 feet. The controller added that the weather was not too bad, but he believed that weather was moving in.

At 1353, ZLA instructed the pilot to contact Southern California (SOCAL) Terminal Radar Approach Control (TRACON) on frequency 134.0, the Banning Radar sector (BANR).

The pilot checked in with BANR, and reported descending through 9,000 feet. He said that he would try to maintain 10,500, but he had gotten pushed down to this altitude. He informed BANR that he might need an instrument landing system (ILS) approach. BANR amended his flight plan to IFR, and told him to expect his clearance in 10 miles. BANR issued an IFR clearance at 1400; it was direct to Orange County via direct Seal Beach VOR (very high frequency omni-directional radio range), maintain 8,000 feet.

About 1407, BANR issued a heading of 240 degrees, vectors to the Orange County final approach course. At 1414, BANR handed the pilot off to SOCAL on frequency 124.1, the Shore Radar sector (SHRR). The pilot checked in to SHRR with Orange County automatic terminal information service (ATIS) information Tango.

At 1421:47, SHRR instructed the pilot to descend and maintain 6,000 feet. About 30 seconds later, SHRR instructed him to turn right to a heading of 270 degrees. About 2 minutes later they instructed him to turn right to 290 degrees, and descend to 5,000 feet. About 50 seconds later, SHRR instructed him to turn to 330 degrees, and contact SOCAL on 121.3, the Tustin Radar sector (TUSR).

The pilot checked in with TUSR, and TUSR issued a heading change to 350 degrees. Twenty-five seconds later, TUSR instructed him to descend and maintain 4,000 feet. Twenty-nine seconds later TUSR instructed him to turn left to 310 degrees. About 1 minute later, TUSR instructed him to turn left to 230 degrees. TUSR added descend and maintain 3,000 feet if he had not already been instructed to do so.

At 1427:44, TUSR stated that the target was 5 miles from Lemon (intersection/outer marker), and said to continue the left turn to a heading of 220 degrees. TUSR also instructed the pilot to maintain 3,000 feet until established on the localizer (course 194 degrees). TUSR cleared him for the ILS runway 19R approach. Nine seconds later, at 1427:53, the pilot acknowledged the instructions. There were no other transmissions from the pilot.

TUSR asked the pilot to say his heading, but received no response. TUSR lost radar contact and asked the Orange County air traffic control tower if they had contact. The tower did not. The controllers discussed the situation and both remarked that the radar target appeared to have made a right turn prior to the lost contact.

PERSONNEL INFORMATION

A review of Federal Aviation Administration (FAA) airman records revealed that the pilot held a private pilot certificate with airplane single engine land and instrument ratings. The pilot held a third-class medical certificate issued on June 4, 2002. It had the limitations that the pilot must wear corrective lenses.

The pilot's charred logbook was in the wreckage. The IIC estimated that the pilot had a total flight time of 890 hours. He logged 25 hours in the last 90 days, which included three round trips between Orange County and Prescott. Two of the return trips to Orange County terminated with an ILS approach. He logged 5 hours in the last 30 days. He had an estimated 740 hours in this airplane; the first flight occurred in April 1992.

AIRCRAFT INFORMATION

The airplane was a Piper PA-24-250, serial number 24-1376. A review of the airplane's logbooks revealed a total airframe time of 4,421 hours at the last annual inspection. An entry on January 13, 2002 recorded an annual inspection. The tachometer read 2,962.1 at the last inspection.

Witnesses familiar with the airplane reported that several years earlier they observed damage to the stabilator. One witness observed the pilot/owner making repairs. The pilot said that he had flown through turbulence severe enough to damage the horizontal stabilator. One witness said that the owner had installed another stabilator. FAA records did not indicate that the owner held an airframe mechanic certificate. The airframe logbooks did not contain an entry for repairs, and the owner did not notify the Safety Board of the damage. A certified copy of the airplane records from the FAA Aircraft Registration Branch did not contain a record of a major repair or alteration.

The engine was a Textron Lycoming O-540-A1D5 engine, serial number L-3608-40. At the last annual inspection, total time on the engine was 3,798.1 hours; time since major overhaul was 615 hours. Technicians installed six new cylinders at the annual inspection.

METEOROLOGICAL CONDITIONS

There was no record of the pilot of N6268P having contacted any Direct User Access Terminal (DUAT) venders or an Automated Flight Service Station (AFSS) for a formal preflight weather briefing.

A staff meteorologist prepared a factual report on the prevailing weather conditions. The following paragraphs summarize his findings; the full report is part of the public docket.

All the weather data used in this report was from official National Weather Service (NWS) sources including the National Climatic Data Center (NCDC). The IIC converted all times to PST.

The NWS Surface Analysis Chart for the southwestern United States depicted the primary synoptic conditions at the surface at 1600 on December 16, 2002, immediately after the accident. The main features included a cold front moving across southern California. The station models across southern California depicted overcast skies with continuous rain. Wind direction surrounding the accident site varied. The wind was from the south and southeast at 15 to 20 knots immediately in the vicinity of the accident site and Orange County Airport. East of the site it was west-southwest at 30 knots. Northwest of the site it was northwesterly at 10 to 15 knots.

The NWS Weather Depiction Chart for the southwestern United States at 1400 depicted an area of IFR conditions by a shaded contour line over southern California. An area of marginal visual flight rules (MVFR) conditions, indicated by an unshaded contour line, surrounded the IFR area. Visual flight rules (VFR) conditions extended over southeast California and Arizona. The accident site was within the area identified under IFR conditions.

The station models on the chart depicted visibilities from 1/2 to 1 3/4 miles in moderate to heavy rain. They depicted overcast skies with ceilings from 200 to 1,200 feet in the vicinity of the accident site.

The NWS Radar Summary Chart for 1415 on December 16, 2002, depicted the conditions prior to the accident. The chart depicted a large area of echoes over Arizona, Nevada, California, and extending over the route of flight. The echo intensities were light to moderate over Arizona, Nevada, and southeastern California. The echoes increased to strong to very strong echoes over southwestern California, with an embedded area of intense to extreme echoes near the coast identified as rain showers. Echo tops ranged from 24,000 to 27,000 feet in the vicinity of the accident site.

The pilot received Orange County weather while en route from Los Angeles Center at 1219. About 1414, the pilot reported that he had Orange County information Tango. Recorded radio transmissions contained no other references to weather reports.

The closest weather reporting station was Orange County Airport; the planned destination that was 11 miles southwest at an elevation of 56 feet. The airport had an Automated Surface Observation System augmented by certified NWS observers. The reported conditions surrounding the time of the accident were:

KSNA weather observation at 1353: wind from 140 degrees at 13 knots gusting to 21 knots; visibility 10 statute miles; a few clouds at 2,700 feet, scattered clouds at 3,800 feet, ceiling broken at 10,000 feet, and overcast at 20,000 feet; temperature 16 degrees Celsius (C), dew point 12 degrees C; and altimeter 29.89 inches of mercury (inHg). Remarks: automated observation system, peak wind from 140 degrees at 26 knots recorded at 1339; rain ended at 1315; sea level pressure 1012.0-hPa; precipitation since last hour less than 0.01 of an inch; temperature 16.1 degrees C; dew point 11.7 degrees C.

KSNA special weather observation at 1424: wind from 160 degrees at 14 knots gusting to 19 knots; visibility 2 miles in moderate rain and mist; a few clouds at 2,100 feet, ceiling broken at 2,800 feet, overcast at 5,000 feet; temperature 15 degrees C; dew point 13 degrees C; and altimeter 29.85 inHg. Remarks: automated observation system, rain began at 1410, pressure falling rapidly, precipitation since last hour 0.05 inches.

KSNA special weather observation at 1433; wind from 150 degrees at 15 knots gusting to 21 knots; visibility 1 1/2 miles in moderate rain and mist; a few clouds at 2,100 feet, ceiling broken at 2,700 feet, overcast at 4,700 feet; temperature 15 degrees C; dew point 13 degrees C; and altimeter 29.85 inHg. Remarks: automated observation system, tower visibility 2 miles; rain began at 1410; precipitation since 1353 at 0.10 inches.

KSNA weather observation at 1453: wind from 170 degrees at 14 knots; visibility 2 miles in moderate rain and mist; scattered clouds at 2,000 feet, ceiling broken at 2,500 feet, overcast at 3,300 feet; temperature 15 degrees C; dew point 13 degrees C; and altimeter 29.84 inHg. Remarks: automated observation system, rain began at 1410; sea level pressure 1010.4-hPa; precipitation since last hour 0.18 inches; temperature 15.0 degrees C; dew point 13.3 degrees C.

KSNA special weather observation at 1502: wind from 160 degrees at 16 knots gusting to 21 knots; visibility 1 3/4 miles in heavy rain and mist; a few clouds at 1,300 feet, ceiling broken at 1,900 feet, overcast at 3,300 feet; temperature 15 degrees C; dew point 14 degrees C; and altimeter 29.83 inHg. Remarks: automated observation system, tower visibility 2 miles; precipitation last observation 0.04 inches.

The closest upper air sounding or rawinsonde was from NWS San Diego Regional Forecast Office (KMYF), station number 72283, located 70 miles southeast of the accident site.

The sounding indicated a moist low-level environment with a relative humidity greater than 75 percent from the surface to 833-mb or 5,369 feet, and there was a temperature inversion from 816-mb or 5,515 feet to 6,000 feet. Another moist layer was above 500-mb or approximately 18,000 feet. The Lifted Condensation Level (LCL) or base layer of the clouds was 944-mb or 1,576 feet, with the Level of Free Convection (LFC) at 932-mb or 1,910 feet. The freezing level was at 675-mb or at 10,544 feet.

The sounding indicated the following stability parameters, a Lifted Index (LI) of 5.7 and a K-Index of 1.9.

The wind profile indicated surface winds from the south-southeast at 18 knots veering to the west and the northwest with altitude. It identified a low-level wind maximum at 2,000 feet with winds of 35 knots. Winds decreased above this level and then increased to a maximum located at 31,000 feet with winds at 111 knots. The estimated mean wind from the surface to approximately 18,000 feet was from 260 degrees at 57 knots. The surface to 2,000 feet mean wind was from 180 degrees at 22 knots.

The staff meteorologist obtained Geostationary Operations Environmental Satellite number 10 (GOES-10) data from the Safety Board's Man-computer Interactive Data Access System (McIDAS) workstation. He obtained both visible and infrared imagery surrounding the time of the accident, and documented relevant images.

The GOES-10 4X magnification infrared satellite image at 1430 depicted a large band of enhanced clouds extending over southern California and bordering over the accident site. The radiative temperature over the site was 230.0 degrees K or -43.16 degrees C, which corresponded to cloud tops in the range of 33,000 feet.

The GOES-10 2X magnification visible image for 1430 depicted a large band of stratiform type clouds consistent with nimbostratus extending over the destination and the accident site. The image depicted several small north-to-south transverse bands of higher clouds.

The closest NWS Weather Surveillance Radar-1988, Doppler (WSR-88D) was at Santa Ana Mountains (KSOX), approximately 8 miles east. The radar produces three basic types of products: reflectivity, radial velocity, and spectral width.

FAA Advisory Circular AC 00-24B titled "Thunderstorms" dated January 2, 1983, also defines the echo intensity levels and potential weather phenomena associated with those levels. If the maximum VIP (Video and Integrator Processor) Levels are 1 "weak" and 2 "moderate," then light to moderate turbulence is possible with lightning. VIP Level 3 is "strong" and severe turbulence is possible with lightning. VIP Level 4 is "very heavy" and severe turbulence is likely with lightning. VIP Level 5 is "intense" with severe turbulence, lightning, hail likely, and organized surface wind gusts. VIP Level 6 is "extreme" with severe turbulence, lightning, large hail, extensive surface wind gusts and turbulence.

The Aeronautical Information Manual (AIM) also references these levels in the Pilot/Controller Glossary under radar weather echo intensity levels.

The KSOX image depicted a large area of echoes over the accident site with reflectivities in the range of 30 to 40 dBZ or VIP Level 2 "moderate" intensity echoes.

The radial velocity wind pattern indicated winds from the south at the surface and veering to the southwest with height with winds from the south-southwest and approximately 30 knots within 5 miles of the accident site. Immediately north and east of the radar site, rapid changes in wind velocity occurred with wind speeds of 44 to 60 knots. The specialist identified no rotational couplets within 5 miles of the accident site.

A sergeant with the Anaheim Police air unit was in his office. He noted that heavy rain began about 1415. About 1430, he heard a report of an airplane crash in Anaheim Hills on the police radio. He immediately accessed the KSOX radar site via the internet. He noted a level 3 or 4 rain cell depicted on the radar in the immediate vicinity of the accident site.

Pilot Reports

Several routine (UA) and urgent (UUA) pilot reports (PIREPs) occurred over California surrounding the time of the accident.

A routine pilot report at 1440 noted that a Boeing 757 flying into runway 19R at Orange County Airport experienced a 45-knot crosswind at 100 feet and light to moderate turbulence.

An urgent pilot report from Van Nuys at 1443 from a Lear Jet pilot noted a gain and loss of 15 knots airspeed at 1,000 feet during descent for landing. The pilot also encountered a 50-knot headwind.

At 1454, a Piper Malibu turboprop pilot reported moderate turbulence at 7,000 feet over Brackett Field (POC), and moderate to heavy rain from Brackett to Riverside.

A Cessna Citation pilot reported moderate to severe turbulence and icing during climb northbound from Burbank at 1531.

In-Flight Weather Advisories

The NWS issues in-flight weather advisories designated as Severe Weather Forecast Alerts (AWW's), Convective SIGMET's (WST's), SIGMET's (WS's), Center Weather Advisories (CWA's), and AIRMET's (WA's). In-flight advisories serve to notify en route pilots of the possibility of encountering hazardous flying conditions, which may not have been forecast at the time of the preflight briefing. Whether or not the condition described is potentially hazardous to a particular flight is for the pilot to evaluate on the basis of experience and the operational limits of the aircraft. The following advisories were in effect.

The NWS had no Convective SIGMETs current for California, and no Severe Weather Forecast Alerts or Center Weather Advisories issued for California on December 16, 2002.

SIGMETs

The NWS Aviation Weather Center (AWC) located in Kansas City, Missouri, had the following SIGMETs valid over the area:

SIGMET Oscar 1 issued at 1130, and valid until 1530, for portions of California, Nevada, Arizona, and coastal waters. The advisory was for occasional severe rime to mixed icing in clouds and in precipitation between 8,000 and 16,000 feet. They expected the conditions to continue beyond 1530.

SIGMET Xray 7 issued at 1030, and valid until 1430, for portions of California, Nevada, Arizona, and coastal waters. The advisory was for occasional severe turbulence below 18,000 feet due to strong low and mid level winds. Pilots in a B-747 near (SAC) and by aircraft over southern California reported the conditions. NWS expected the conditions to continue beyond 1430. NWS updated SIGMET Xray at 1429 and included the accident site.

AIRMETs

The NWS had a full set of AIRMETs issued at 1233 current for the area; AIRMET Sierra for IFR conditions and mountain obscuration, AIRMET Tango for turbulence and low level wind shear, and AIRMET Zulu for icing conditions. The AIRMETs were:

AIRMET Sierra for IFR conditions over portions of California, Oregon, and coastal waters. The advisory warned of occasional ceilings below 1,000 feet agl and visibilities below 3 miles in clouds, precipitation, fog, and mist. NWS expected the conditions to continue beyond 1900 through 0100 over the Sierra Nevada Mountains and northeastern California and ending elsewhere between 1700 and 1900.

AIRMET Sierra was also current for mountain obscuration over portions of California, Oregon, Washington, Idaho, Montana, Wyoming, Nevada, and Utah. The advisory warned of mountains occasional obscured in clouds, precipitation, fog, and mist. NWS expected conditions to develop between 1500 and 1800 over southern and eastern Utah, Colorado, and southwestern portions of Wyoming. They expected the conditions to continue beyond 1900, and spread across the remainder portions of western Colorado, northern Nevada, and northwestern New Mexico by 0000. They expected the conditions to continue beyond 0100 over the rest of the area.

AIRMET Tango was also current for most of California, Oregon, Washington, Nevada, Idaho, Montana, Wyoming, Utah, Colorado, New Mexico, and Arizona. The advisory warned of occasional moderate turbulence below 18,000 feet due to moderate to strong westerly winds and mountain wave activity. NWS expected conditions to continue beyond 1900 through 0100 in the southern California area. The accident site was within the boundaries of the advisory.

A similar AIRMET issued for the same region called for occasional moderate turbulence between 18,000 and 41,000 feet due to wind shear associated with the jet stream and mountain wave activity. The AIRMET extended over the accident site at higher altitudes.

The advisory also warned of low-level wind shear potential below 2,000 feet agl due to strong and gusty low-level winds over central and southern California.

AIRMET Zulu was also current over portions of California, Nevada, Utah, Colorado, Arizona, New Mexico, and coastal waters. The advisory warned of moderate rime to mixed icing in clouds and in precipitation between the freezing level and 28,000 feet. NWS expected these conditions to continue beyond 1900 through 0100. The accident site was within the boundaries of this advisory.

Terminal Aerodrome Forecast (TAF)

The Terminal Aerodrome Forecast (TAF) issued for KSNA at 1110 on December 16, 2002, for the period from 1100 through 1000 on December 17, 2002, was for the following conditions.

KSNA forecast from 1100: wind from 160 degrees at 15 knots gusting to 25 knots; visibility better than 6 miles; scattered clouds at 3,000 feet, ceiling broken at 5,000 feet. From 1300, wind from 160 degrees at 15 knots gusting to 25 knots; visibility better than 6 miles; ceiling broken at 3,000 feet; and overcast at 5,000 feet. From 1500: wind from 160 degrees at 15 knots gusting to 25 knots; visibility 5 miles in light rain showers and mist; scattered clouds at 1,500 feet, ceiling overcast at 2,500 feet. From 1700: wind from 190 degrees at 14 knots; visibility 3 miles in moderate rain and mist; ceiling broken at 1,500 feet. From 2200: wind from 220 degrees at 10 knots; visibility 4 miles in moderate rain showers and mist; scattered clouds at 1,500 feet, ceiling overcast at 2,500 feet.

COMMUNICATIONS

The airplane was in contact with SOCAL TRACON Tustin Radar sector on frequency 121.3.

WRECKAGE AND IMPACT INFORMATION

Investigators from the Safety Board, the FAA, New Piper Aircraft Corporation, and Textron Lycoming examined the wreckage at the accident site.

The wreckage was scattered through a residential area, and covered an area over 1/4 mile long. The main wreckage was in a residence. The engine and propeller separated. The propeller came to rest in the principal impact crater (PIC). The inverted engine came to rest, in the direction of the main wreckage, several feet from the PIC.

The cabin area came to rest in a garage about 20 feet from the PIC. Witnesses stated that the garage exploded and burst into flames several minutes after the accident. Wreckage pieces that were not inside the garage were not charred. Approximately 2/3 of the left wing separated; this piece was inverted and along the outside of the garage wall.

The debris path ran in a southeasterly direction. The first piece (FP) located in the debris path was a 6-foot section of the outboard left wing, which included the wing tip. Approximately 50 feet southwest of the FP was the outboard 3 feet of the right horizontal stabilator. About 120 feet southwest of the FP was the outboard 1/2 of the left horizontal stabilator.

The next pieces found were left and right aileron pieces, which were near to each other, and a piece of empennage skin. The empennage was about 2/3 of the way into the debris field. Nearby it was the center section of the left aileron with the counterweight attached. The rudder mass balance weights came to rest on a roof across the street from the main wreckage.

A portion of the aft center section of the right wing was in the street in front of the main wreckage. The upper wing surface buckled diagonally forward and outboard. The upper wing surface had a cable tear that started near the trailing edge and curved forward as the tear progressed outboard. The tear ended at a rib forward of the outboard end of the flap. This piece had the outboard 2/3 of the flap and inboard 1/2 of the aileron attached to it. The inboard 1/2 of the flap exhibited about 45 degrees up permanent deformation.

MEDICAL AND PATHOLOGICAL INFORMATION

The Orange County Coroner completed an autopsy. The FAA Bioaeronautical Sciences Research Laboratory, Okalahoma City, Oklahoma, performed toxicological testing of specimens of the pilot. The analysis of the specimens contained no findings for volatiles or tested drugs.

TESTS AND RESEARCH

Investigators examined the wreckage on site and at Eastman Aircraft, Corona, California, on December 18, 19, and 27, 2002.

ENGINE

The engine separated from the airplane and did not exhibit thermal damage. The engine had dirt and tree roots caked on the right side.

Investigators removed the spark plugs. The plugs did not exhibit mechanical damage, and the gaps were similar. The spark plug electrodes were gray in color.

A borescope inspection revealed no mechanical deformation on the valves, cylinder walls, or internal cylinder head.

Investigators did not locate the left magneto, and the right magneto separated. It sustained mechanical damage, and investigators did not test it.

The carburetor sustained mechanical damage and fractured into pieces. The right metal float exhibited crush damage, but the left float did not. The finger screen was clean.

The oil filter sustained mechanical damage. The oil suction screen was clean.

The drive coupler on the vacuum pump was undamaged. One of the carbon vanes cracked; the rest were undamaged.

PROPELLER

One propeller blade separated. It exhibited trailing edge S-bending. The leading edge had scratch marks and the back had chordwise striations. The blade twisted toward the low pitch position. The second propeller blade had chordwise striations along the leading edge. The third blade had no striations and was not bent.

AIRFRAME

Left Wing

The leading edge of the left wing was crushed aft to the spar. Beginning at the midflap and midchord point, the upper skin exhibited wrinkles that went from inboard to outboard and trailing edge toward leading edge.

The outboard 5 feet 8 inches of the wing separated. The bottom spar separated and the spar web tore along a jagged 45-degree angle from bottom to top, and inboard to outboard. The spar web exhibited compression wrinkles whose focal point on the upper spar was directly above the separation point of the lower spar. The upper spar separated several inches outboard of the focal point. The top of the upper spar tore along a 45-degree angle from inboard to outboard and front to rear.

The lower skin of the separated left wing section separated along a jagged tear; the skin pulled from the ribs and spar. This lower skin rotated forward so that the upper and lower skins made a relatively flat piece. The inboard rivets at the spar/skin separation points pulled through the skin while the outboard rivets sheared through the skin.

The left aileron separated in three sections (symmetric to the right side). Both upper and lower skins exhibited skin displacement and tears in an outward direction in the hinge cutout areas. The upper and lower aileron stops were not damaged. The outboard aileron attachment fitting bent inboard, and the inboard fitting bent outboard. The fractured control rod ends exhibited cupped, matte surfaces. The aileron bearings corroded to the extent that material was missing.

Right Wing

The upper spar cap separated 71 inches out from the root, and the lower spar cap separated about 67 inches from the root. This was about 2 feet outboard of the right main landing gear. The spar that remained attached exhibited about 10 degrees of permanent deformation on the upper spar cap, and separated from the spar webbing. The lower spar cap beneath this area exhibited about 10 degrees of downward permanent deformation, and separated from the spar webbing.

The upper spar cap had a 45-degree shear lip. A 6-foot section of the upper spar cap separated, and imbedded itself in the eaves of a neighbor's house about 50 feet from the main wreckage.

The outboard portion of the wing bent up and around the spar. The upper spar cap exhibited permanent upward deformation at the separation point. About 3 inches outboard of the separation point, the upper spar cap bent down. The spar web exhibited wrinkles that pointed diagonally top to bottom at a focal point beneath the downward bend on the top spar.

Empennage

The empennage separated from the airframe at the aft bulkhead.

The vertical stabilizer's forward lower end exhibited crush damage. The damage was aft and bent the skin up and to the right. The vertical stabilizer bolts to a bracket on the fuselage. The left side of this bracket sheared and separated through half of its width, and showed upward displacement.

Investigators inverted the separated right wing, and placed it above fuselage in front of the empennage. They noted that the inboard leading edge section of the separated right wing exhibited crush damage similar in shape to the top of the fuselage and the vertical stabilizer. The top of the fuselage caved inward in this area.

The damage to the left and right horizontal stabilizers was similar. Both stabilizers separated downward at midspan, and the separation continued through the trim tab.

The left horizontal stabilator separated along a jagged tear from outboard to inboard and front to rear. Rivet holes in the aft portion of the top skin deformed elliptically upon separation. The forward holes had the long axis of the deformation parallel to the lateral axis. The long axis of the deformation rotated counterclockwise progressing from the front to the rear holes.

The right horizontal stabilizer separated from inboard to outboard. The separation was a jagged tear. The rivets pulled through the skin, and the rivets deformed elliptically upon separation. Proceeding outboard, the long axis of the deformation progressed clockwise.

The fuel selector valve fractured and separated, the stub was in the right main position. The fuel boost pump switch was bent to the right.

The manufacturer's representative estimated that the flaps were down 10 degrees.

ADDITIONAL INFORMATION

The IIC released the wreckage to the owner's representative.

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