NTSB Factual Report

HISTORY OF FLIGHT

On October 24, 2008, about 1901 eastern daylight time, a Piper PA-24-260, N8820P, was destroyed when it departed controlled flight and impacted trees and terrain near Red Hill, Virginia, while being vectored for an instrument approach to Charlottesville-Albemarle Airport (CHO), Charlottesville, Virginia. The certificated private pilot and the passenger were fatally injured. The personal flight was operated under the provisions of 14 Code of Federal Regulations Part 91. Night visual meteorological conditions prevailed at the destination airport, and the flight operated on an instrument flight rules (IFR) flight plan.

According to Federal Aviation Administration (FAA) and Lockheed Martin Services (LMS) information, about 1633 the pilot telephoned LMS, and filed an IFR flight plan from Asheville Regional Airport (AVL), Asheville, North Carolina to Orange County Airport (OMH), Orange, Virginia. The pilot filed CHO as the alternate airport, which was 25 miles west-southwest of OMH. About 1726, the airplane departed AVL.

Air traffic control (ATC) radar tracking data indicated that the airplane's cruise altitude was 7,000 feet above mean sea level (msl). About 9 minutes prior to the accident, the pilot requested the "GPS-8" instrument approach procedure (IAP) to OMH. About 6 minutes prior to the accident, when the airplane was 45 miles southwest of OMH, ATC cleared it to descend to 4,000 feet. Approximately 2 minutes after the descent clearance was issued, the pilot radioed ATC that the visibility at OMH was "right at the minimums," and requested a diversion to CHO for the instrument landing system (ILS) approach to runway 3. ATC approved the request, and issued a corresponding heading change to "three six zero" degrees. Two minutes after the heading change instruction, ATC cleared the airplane for the approach. Two minutes later, three "mayday" calls, presumed to be from the accident airplane, were broadcast in rapid succession on the frequency. No further transmissions were received from the accident airplane.

PERSONNEL INFORMATION

According to FAA records, the pilot held a private pilot certificate, with airplane single-engine land and instrument airplane ratings. The pilot’s logbook indicated that as of October 12, 2008, he had accumulated approximately 1,070 total hours of flight experience, including 180 hours at night, 157 hours in complex airplanes, 82 hours of actual instrument time, and 75 hours of simulated instrument time. His logbook indicated that he had 71 hours in the accident airplane make and model. The pilot's most recent flight review was in January 2008, and his most recent instrument flight proficiency check was in April 2008. His most recent FAA third-class medical certificate was issued in August 2007.

AIRPLANE INFORMATION

According to FAA and Piper information, the accident airplane was manufactured in 1965. In 1981, and again from 1983 to 1985, the airplane was registered in Canada. The accident pilot was approximately the seventh owner of the airplane; he acquired it in March 2007.

The airplane was a four place, low wing model of all metal construction, with electrically actuated, retractable, tricycle-configuration landing gear. Primary flight controls included a stabilator, which functioned as both the horizontal stabilizer and elevator. Secondary flight controls included electrically-actuated flaps, and manually-actuated stabilator pitch trim. The airplane was equipped with an autopilot.

Maintenance records indicate that in 1992, several aftermarket speed modifications were installed on the airplane. The airplane was equipped with a Lycoming IO-540 piston engine, and a McCauley three blade, constant-speed propeller. The engine was overhauled by Teledyne Mattituck Services, and installed on the airplane in October 2000. The logbook entry for the installation of the overhauled engine indicated that the airplane had accumulated a total time in service of 9,270 hours, the tachometer registered 6,656 hours, and the engine had accumulated a total time in service of 3,965 hours, with 0 (zero) hours since major overhaul (SMOH).

The most recent annual inspection was accomplished in October 2007. At that time, the airplane had accumulated a total time in service of 9,460 hours, the tachometer registered 6,866 hours, and the engine had accumulated a total time in service of 4,165 hours, with 200 hours SMOH. The final maintenance entries were dated August 8, 2008, and listed a tachometer time of 6,921.8 hours. The engine tachometer was rendered unreadable by the accident. According to the pilot's logbook, he had flown the airplane approximately 71 hours since the October 2007 annual inspection. The National Transportation Safety Board (NTSB) was unable to determine whether any other persons also flew the airplane during the period between the 2007 annual inspection and the accident.

METEOROLOGICAL INFORMATION

Local sunset occurred at 1823. The 1853 recorded weather observation at CHO included zero wind, 10 miles visibility, broken ceiling at 1,900 feet, overcast ceiling at 2,600 feet, temperature 11 degrees C, dew point 8 degrees C, and an altimeter setting of 30.24 inches of mercury. The 1900 OMH observation included winds from 010 degrees at 4 knots, 10 miles visibility, broken ceiling at 1,900 feet, overcast ceiling at 2,600 feet, temperature 12 degrees C, dew point 10 degrees C, and an altimeter setting of 30.27 inches of mercury.

AIRMETs for mountain obscuration and IFR conditions, and occasional moderate turbulence below 12,000 feet, were current for the route of flight. No Convective SIGMETs, SIGMETs, or Weather Watches were current for Virginia during the period of the flight.

Winds-aloft information indicated the presence of winds from the south, with velocities that ranged from 30 to 45 knots for the flight altitudes and the geographic regions of the diversion and the accident. Weather radar summary data indicated that a band of echoes associated with rain and rain showers was present at the location where the pilot decided to divert to CHO, and extended to the accident site. The weather radar information also indicated the presence of wind shear values from 12 to 18 knots along the edges of the echo and in the vicinity of the flight track, which were consistent with an encounter with moderate to severe turbulence along the flight track.

The freezing level varied between 9,000 and 12,000 feet msl along the route of flight.

AIRPORT INFORMATION

The straight-in minima for the GPS-8 IAP to OMH were 1,120 feet msl minimum descent altitude and 1 mile visibility, and the circling minima were 1,360 feet msl, and 1 1/4 miles visibility. The straight-in minima for the ILS IAP to CHO runway 3 were 856 feet msl, and 1/2 mile visibility.

WRECKAGE AND IMPACT INFORMATION

The accident site was located in a wooded area, approximately 12 miles south of CHO. The debris field measured approximately 400 feet long and 100 feet wide. The debris path was oriented along a magnetic heading of approximately 195 degrees.

The outboard 3 feet of the right stabilator was the first component in the debris path. A corresponding segment from the left stabilator was the next item in the debris path; this component was located 15 feet southwest of the right stabilator segment. The third item in the debris path was the inboard 3 feet of the left stabilator. This was located approximately 70 feet south-southwest of the outboard left stabilator segment. No impact damage was observed on these components, and the trees in the vicinity of these components were undisturbed.

Witness marks indicated that the airplane first struck trees at a height of approximately 50 feet above ground level (agl), approximately 200 feet beyond the first stabilator segment. Wing, aileron and flap segments were distributed along the debris path subsequent to the tree strikes, and the components exhibited impact damage. All fuel tanks were fragmented. The initial ground impact point was a crater that measured approximately 15 feet long, 8 feet wide, and 2 feet deep. The crater was approximately 250 feet beyond the first stabilator segment. The main wreckage, comprised primarily of cockpit, cabin and inboard wing sections, and the main landing gear, was located 50 feet beyond the initial ground impact point. The engine was the final component in the debris path, and was located 100 feet beyond the main wreckage.

The cockpit/cabin area was essentially upright, with significant crush, disruption and fracture damage. The aft fuselage/tailcone and portions of the empennage also exhibited significant crush damage, and were located east of the initial ground impact point. The inboard section of the right stabilator, and most of the vertical fin, remained attached to the aft fuselage/tailcone.

One propeller blade was found separated from the propeller hub, approximately 60 feet west of the initial ground impact crater. The blade was bent approximately 110 degrees aft at the outboard end, and exhibited trailing edge S-bending, and slight chordwise scratching. The other two blades were found in the crater, with one attached to the hub. The blade attached to the hub was bent 20 degrees forward in an arc starting at the two-thirds span point. The outboard 6 inches of the other blade was bent aft 15 degrees, and the blade had two 1/2 inch radius bends in the trailing edge near the two-thirds span point.

The engine was found inverted approximately 150 feet beyond, and on terrain 30 feet higher than, the impact crater. There was evidence of a small fire in the vegetation surrounding one of the mufflers. The engine was devoid of most accessories, intake and exhaust tubing, and mounting hardware. All cylinders were attached and relatively intact, including their valve covers. The oil sump was impact-separated, and the engine case was cracked in several locations. A hole in the forward bottom of the crankcase measured approximately 10 inches long and 6 inches wide; the crankshaft and piston rods visible through the hole were intact.

Both magnetos sparked at all towers when rotated by hand. All six bottom spark plugs, and two of the top spark plugs were removed from the engine, and all had electrodes of light gray coloration, with normal wear. The other four top spark plugs could not be removed due to impact damage. The fuel injector servo was fragmented, and the fuel screen was missing. The fuel flow divider contained clean fuel, and the diaphragm was intact and clean. Four of the fuel injector nozzles were intact, one was bent, and one was fractured. None passed the "sight test," due to the presence of mud and other debris. The dry-type vacuum pump was impact-separated and fragmented, and no vanes or vane fragments were found. The oil suction screen and oil filter were free of metallic debris. The aft section of the propeller hub remained attached to the crankshaft, and all hub-to-shaft attach hardware were in place and safetied. The crankshaft could not be rotated by hand due to the deformation of the engine case. Examination of the engine and engine accessories did not reveal evidence of any pre-impact anomalies.

All of the instruments and avionics were separated from the instrument panel, and from the cockpit area. Most exhibited significant crush damage and/or fragmenting. The ignition switch was found in the "Both" position, and the fuel selector valve was set to the "Right Main" tank. No other switch or control settings could be determined.

Flight control continuity was established for the ailerons, rudder, stabilator, and stabilator trim. The stabilator trim jackscrew extension indicated a trim setting of full airplane nose up. The flap jackscrew extension indicated a flap setting of approximately 23 degrees. The two main landing gear assemblies were found in their respective wheel wells, and the nose landing gear was found 20 feet south of the main wreckage.

MEDICAL AND PATHOLOGICAL INFORMATION

The FAA Civil Aero Medical Institute (CAMI) toxicology results for the pilot were negative for screened drugs. Ethanol was detected (12 mg/dL) in muscle tissue, but was not detected in the liver. Putrefaction of the specimens was noted. Tests for carbon monoxide and cyanide were not performed. An autopsy was conducted by the Virginia Department of Health in Richmond, Virginia; the autopsy report listed the cause of death as "blunt force trauma," and did not list any contributing factors.

ADDITIONAL INFORMATION

Airspeed Limitations and Indicator Markings

According to the FAA publication "Pilot's Handbook of Aeronautical Knowledge (FAA-H-8083-25)," the maximum calibrated airspeed for normal operation ( referred to as Vno, or maximum structural cruise speed), was the "speed at which exceeding the limit load factor may cause permanent deformation of the airplane structure." In the same document, the FAA cautioned pilots that they should "not exceed this speed except in smooth air." FAA regulations required that airspeed indicators for airplanes that weighed less than 12,500 pounds, and that were manufactured after 1945, were required to be marked in accordance with a "standard color-coding system." A green arc on the airspeed indicator was required to depict the normal operating speed range of the airplane, and the upper limit of the green arc was defined by Vno. A red line was required to depict the "never exceed speed" (referred to as Vne), and operation of the airplane above this speed was prohibited.

Airworthiness Directives, Service Bulletins, and Service Letters

Starting in 1972, empennage vibration concerns prompted the issuance of PA-24 Service Bulletins and Letters from Piper Aircraft. According to Piper, "Piper Service Bulletins are of special importance and Piper considers compliance mandatory. These are sent to the latest U.S. registered owners and Piper Service Centers." Service Letters "deal with product improvements and service hints pertaining to the aircraft. They are sent to Piper Service Centers and sometimes directly to owners, so they can properly service the aircraft and keep it up to date with the latest changes. Owners should give careful attention to the service letter information."

In August 1972, Piper issued Service Bulletin (SB) No. 362. The SB stated that "Piper Aircraft Corporation is investigating the effects of improper maintenance and/or unauthorized repair procedures with respect to possible deterioration of the margin of safety when applied to flutter characteristics of the horizontal and vertical tail surfaces. In order to provide additional margin and in the interest of safety, Piper has reduced the never exceed speed" for the PA-24-260. The SB reduced the Vne from 227 mph calibrated air speed (CAS) to 203 mph for the PA-24-260. The SB specified that a placard denoting the revised Vne was to be installed on the airspeed indicator.

In October 1972, Piper issued SB 362A, which supplemented, but did not supersede, SB 362. The subsequent SB (SB 362A) prescribed the installation of Piper Rudder Balance Weight Installation Kit 760-705. According to SB 362A, the revised Vne would remain at 203 mph, but "installing rudder balance weights...will prevent possible adverse airplane vibration effects, thus providing a greater margin of safety at higher speeds."

In late 1972, the FAA issued Airworthiness Directive (AD) 72-22-05, which restricted the PA-24-260 Vno to 167 mph CAS, and the Vne to 188 mph. The AD stated that installation of Piper Rudder Balance Weight Installation Kit 760-705 would allow the Vno and Vne to be increased to 180 and 203 mph CAS, respectively. Maintenance records indicated that the Rudder Balance Weight Kit 760-705 was installed on the accident airplane in December 1972, by Gillis Aviation in Montana.

In June 1974, Piper issued Service Letter 687, which modified the stabilator by installing stabilator tip weights, stabilator hinge reinforcements and stabilator tab hinge reinforcements, in accordance with Piper Service Kit 760-747. This modification, when installed in conjunction with or subsequent to the Rudder Balance Weight Kit 760-705, permitted PA-24-260 airplanes to be returned to the original Vne of 227 mph

NTSB Probable Cause

The pilot's failure to maintain aircraft control due to an improper repair to the stabilator, which resulted in an in-flight failure of the stabilator. Contributing to the accident was the descent in turbulence, at airspeeds above the maximum structural cruise speed.