Hot Springs, AR, USA
N314M
Rockwell Commander 114
The airplane was on an instrument flight plan at night, with a destination of Little Rock, Arkansas. The pilot reported a loss of engine power, and he diverted into Hot Springs, Arkansas. The airplane impacted a brick house, approximately 6,000 feet short of the runway. The airplane engine ignition system's single-drive dual-magneto exhibited evidence of melted plastic on its four-lobe breaker cam. The cam itself exhibited "bluing" discoloration and was dry of lubrication. The internal damage to the magneto suggested that the breaker cam's shaft had been forcibly pushed into the magneto. Evaluation of the magneto housing revealed a 7/8-inch gouge, which matched the dimension of its hold-down clamp. The magneto had been removed during the airplane's last annual inspection for a normal maintenance inspection. The airplane had flown approximately 148 hours since its annual inspection.
HISTORY OF FLIGHT On December 5, 2002, at approximately 1858 Central Standard Time, a Rockwell Commander 114, N314M, was destroyed when it struck a house subsequent to a loss of engine power while in cruise flight near Hot Springs, Arkansas. The instrument rated private pilot received serious injuries, and his passenger was fatally injured. The pilot/owner was operating the airplane under Title 14 CFR Part 91. Night visual meteorological conditions prevailed for the cross-country personal flight that originated from Dallas, Texas, 1 hour, 36 minutes before the accident. The pilot was flying on an IFR (instrument flight rules) flight plan (he canceled his IFR flight plan approximately 2 minutes before impact) and his destination was Little Rock, Arkansas. The Federal Aviation Administration (FAA) Air Traffic Controller (ATC; tower control) at Adams Field, Little Rock, Arkansas, said that the airplane departed at 1113, on an IFR for Addison Airport, Dallas, Texas. The pilot's flight planning sheets indicate that the 253 nautical mile (nm) flight would take approximately 1 hour, 50 minutes to fly. While at Addison Airport, the pilot had the airplane fueled (topped off) with 30 gallons of 100 LL (low lead) and 2 quarts of oil. ATC at Addison Airport said the airplane departed at 1722, and was cleared IFR, at 9,000 feet, for his route back to Little Rock, Arkansas. On the voice tapes, retrieved from Memphis ARTCC (Air Route Traffic Control Center), the pilot had requested a descent down to 7,000 feet at approximately 1851. At approximately 3 1/2 minutes later, the pilot asked to divert to Hot Springs, Arkansas, due to an "engine problem." The ARTCC controller cleared him direct, and told the pilot that the airport was at his 10 o'clock position for 4 nm. The pilot closed his flight plan and changed his radio frequency to Memorial Field's CTAF (common traffic advisory frequency). Witnesses at Memorial Field's FBO (fixed base operator) facility said that the pilot called in reporting that his engine had "quit." Another pilot, flying near Pine Bluff, Arkansas, was monitoring the same CTAF frequency and reported that the accident pilot did declare an emergency for "some kind of engine malfunction." He next heard the accident pilot say "we are not going to make the airport. We are going into the lake." At 1859, numerous 911 emergency calls were received by the Garland County Sheriff's Department reporting that an airplane was going down. One individual said it sounded like "fire crackers or something back firing." Another said the engine was running "really bad." The airplane impacted a lake-side house, at approximately 6,000 feet from the end of the runway. PERSONNEL INFORMATION The pilot held a private pilot certificate with single engine land and instrument ratings. He was issued a third class airman's medical certificate on March 19, 2001. The certificate contained no limitations. On an insurance application, dated October 24, 2002, the pilot reported that he had 825 hours of flying experience, with 617 hours in make and model. He said that he had 125 hours of flight experience during the last 12 months. He also indicated that his last flight review was on March 1, 2001. The pilot purchased the airplane on September 8, 1998, with 3,070 hours of flight time on it. AIRCRAFT INFORMATION The airplane was a single engine, propeller-driven, four seat airplane, which was manufactured by Rockwell Commander Aircraft Company, in 1977. The airplane had a maximum takeoff gross weight of 3,140 pounds. It was powered by a Lycoming IO-540-T4B5D, reciprocating, normally-aspirated, fuel injected, direct-drive, air-cooled, horizontally-opposed, six-cylinder engine, which had a maximum takeoff rating of 260 horsepower at sea level. Maintenance records indicate that the last annual inspection was completed on February 18, 2002, and at that time the total time on the airplane was 3,646 hours. This annual inspection included the removal of the magneto (Bendix Ignition System D-3000 single-drive dual magneto) for a required 500 hour inspections. The only documented maintenance that was done on the airplane's engine, after the February 18, 2002, annual inspection, was an engine oil change on October 15, 2002, with a tach time of 3,762.8 hours. At the time of the accident, the airplane had 3794.65 hours, or 149 hours since annual. METEOROLOGICAL INFORMATION At 1853, the weather conditions at Hot Springs Memorial Field, Hot Springs, Arkansas (elevation 540 feet), 050 degrees for 2 nm from the accident site, were as follows: wind calm: visibility 10 statue miles; cloud condition clear; temperature 37 degrees Fahrenheit; dew point 27 degrees Fahrenheit; altimeter setting 30.36 inches. The official sunset, on December 5, 2002, at Hot Springs, Arkansas, occurred at 1702. On the same day, the moon rose at 0835 and it set at 1824. COMMUNICATIONS The FAA did not transcribe the recorded transmissions between the pilot and Memphis ARTCC because the pilot canceled IFR services just prior to the accident. The National Transportation Safety Board did transcribe the last approximate 6 minutes before the pilot left the ARTCC frequency, but due to lack of equipment, the exact time of each transmission was not captured. The following transcript is from approximately 1851 to 1857: Pilot: Aero Commander 314 Mike, we'd like to descend out of 9ner, if we could, down to 7. Memphis Center: 314 Mike descend and maintain 7,000, Hot Springs altimeter remains 30.35. Pilot: 9 for 7, 13 Mike. Approximately 3-½ minutes later. Pilot: Center 14 Mike, ah, we've got an engine problem here. I'd like to go ahead and ah cancel, or rather re route and stop at Hot Springs. Memphis Center: 14 Mike ..[stepped on] .. descend and maintain 3,000, Hot Springs is at 10 o'clock at 4 miles, do you have it in sight. Pilot: I've got it in sight now. Memphis Center: 14 Mike cleared to Hot Springs, Springs via direct and you're cleared visual approach to Hot Springs. Pilot: Ok, we'll go ahead and cancel, ah, now and go ahead into ....[broken]. Memphis Center: 14 Mike, roger, cancellation and ah, give me a call when your on the ground at Hot Springs if you would on this, on 118.5. Pilot: And well can you give me, ah, the local frequency there please. Memphis Center: Stand by. Memphis Center: 14 Mike, stand by one. Memphis Center: 14 Mike 123.0, I believe is the Unicom over there. Pilot: ok 23.0, we've had ah, ah, big loss of airspeed and power, and my exhaust gas temperature is way off the scale. I'm not exactly sure what is going on. I'm going to put it down. Memphis Center: 14 Mike roger that, and, like I say I'd like a call on the ground if you would please. No traffic observed in the pattern, you can change to advisory, and I would like a call. Pilot: 123.0. Memphis Center: 123.0. Pilot: Thank you. End. AIRPORT INFORMATION The Hot Springs Memorial Field (elevation 540 feet), Hot Springs, Arkansas, is not serviced by a control tower. The airport has two runways: 05-23 which is 6,595 feet, and 13-31 which is 4,099 feet. Runway 05 has four instrument approaches to it. They include an ILS/DME and a VOR instrument approaches. The airport is serviced by a Unicom/CTAF of 123.0 MHz. WRECKAGE AND IMPACT INFORMATION The airplane was located in the southwest side of a brick home (N34 degrees, 27.79 minutes; W93 degrees, 07.31 minutes; elevation 407 feet) with its' engine in the second floor master bedroom, and its' empennage and mid to aft fuselage extended to the ground. The longitudinal orientation of the airplane was 050 degrees. There was no postimpact fire, but rescue personnel reported a strong smell of fuel at the scene. All of the airplane's major components were accounted for at the accident site. The left wing was separated from the fuselage at its' root, and was suspended in a tree approximately 60 feet prior to the house. Its' leading edge had 3 indentations in it, each approximately 12 to 16 inches wide and 18 to 26 inches deep. The right wing remained attached to the fuselage, and exhibited aft compression along its' outer 2/3 leading edge. The midsection of the wing's skin exhibited two tears aft to forward and forward to aft, which met at the mid section of the wing. The empennage was resting on the ground, and its' vertical stabilizer was bent approximately 60 degrees to the right. Both sides of the horizontal stabilizer (cruciform type) remained attached with minimal damage. The landing gear was found in the down position and the flaps appeared to be down, but could not be confirmed from cockpit indications. The engine's exhaust system was bent, several valve push rods were bent, several spark plug leads were broken, and the fuel injection servo was separated. After these items were repaired, another propeller was installed, and the magneto was replaced with a serviceable unit, an engine run was attempted on January 17, 2003. The engine started, but would not sustain operation. A second attempt to start the engine was made on April 23, 2003. Upon reexamining the engine, an intake leak was found on the number 2 cylinder. This was repaired and the engine was run through its full power band. The propeller hub spinner was compressed aft with striations longitudinally aligned with the fuselage. Two of the propeller blades were bent aft approximately 40 degrees, and both blades exhibited leading edge chordwise polishing. The third blade was bent approximately 5 degrees aft. TESTS AND RESEARCH The airplane wreckage was recovered to a salvage facility near Dallas, Texas, and the NTSB investigative team examined the engine on December 13, 2002. Examination of the airplane's magneto, a Bendix D6LN-3000, part number 10-682560-11, serial number 8233105, revealed that the four-lobe breaker cam, which is driven by a single drive shaft, exhibited evidence of melted nylon that was consistent with the nylon cam followers located on the contact assemblies (manufactured by Aero Accessories, Inc.). The cam itself exhibited "bluing" discoloration and was dry of lubrication. The lubricator felts on the cam follower assemblies were dry of lubricant. The bearing seal also exhibited the loss of grease. A manufacturer's representative of the magneto said that the normal internal operating temperature of the Bendix 3000 is approximately 150 to 200 degrees F. The nylon cam followers on the contact assemblies, according to their manufacturer, were made of DuPont Zytel 103 and melt at 505 degrees F. According to Machinery's Handbook, 24th edition, the bluing on the cam begins to occur at about 550 degrees F., and can persist through about 650 degrees F. A manufacturer's representative of the contact assemblies said that the excessive heat exposure to the nylon cam followers would have melted their ends, subsequently the contact points would not obtain their proper opening clearance for operation. Additionally, he said the excessive temperatures would have allowed the nylon cam followers to deform and become loose about their rivets, which retain them onto their point spring. The magneto with all its' parts was sent to the manufacturer for further evaluation, in the presence of an NTSB investigator. The manufacturer's senior engineer observed the following: "Cam follower deformation against the cam. As the cam follower decreases in height due to wear against the cam, timing becomes increasingly late and point opening decreases. The plastic cam followers were both found to be deformed at their contact areas with the cam. The wear on these cam followers was accelerated by the fact that the cam had been overheated and had lost lubrication. Cam overheating, in turn, was caused by the pinion gear rubbing against the distributor block. The localized heating at the gear and block contact area was conducted to the cam by the steel rotating magnet shaft." "The pinion gear is designed not to rub on the distributor bock. The rotating magnet shaft assembly, with pinion gear attached, was found displaced from its normal assembly position: The shaft had been forcibly pushed into the magneto. In addition to the damage where the pinion gear rubbed on the distributor block, displacement of the shaft into the magneto is evidenced by the matching rub marks on the wave washer, oil slinger, housing, ball bearing inner race, and rotating magnet shaft. The deformed areas on the oil slinger, both where the wave washer dented it and where it spun against the bearing inner race, also demonstrate the shaft displacement. The shaft, wave washer, oil slinger and bearing inner race are all designed to rotate together. The housing does not rotate. However, with the rotating magnet shaft pushed in toward the housing, the oil slinger rubbed on the housing. Friction between the slinger and the housing acted as a brake, which slowed or stopped the slinger and wave washer. Friction between the slinger and the ball bearing inner race caused the inner race to also stop or slow in its rotation while the shaft continued to rotate. The shaft at the bearing seat was worn to .00016 inch below its design limit, and the bearing inner race ID was worn to .00017 over its design limit. Friction between the shaft and the inner race caused the grease captured in the bearing to overheat and partly escape. The force that caused the shaft to be pushed into the housing was sufficient to cause the deformation of the steel oil slinger where the wave washer contacts it." The magneto's housing flange area exhibited a 7/8 inch gouge, which matched the dimension of its' hold down clamp. MEDICAL AND PATHOLOGICAL INFORMATION The Garland County Sheriffs Criminal Investigative Division (CID), had a sample of the pilot's blood sent to the State Crime Laboratory, Little Rock, Arkansas, for toxicological testing. The pilot's blood had no indication of alcohol; however, a Gas Chromatography Mass Spectrograph [GCMS] test was positive for cocaine. The Chief Forensic Toxicologist at the State Crime Laboratory said that they did not perform a definitive analysis of the blood to determine the level of cocaine or its metabolites. He also stated that the specimen was noted to have been obtained at 2200 on the day of the accident. One of the first responders to the accident was a medical doctor. He said that he intubated the pilot immediately, and he stated that "no topical cocaine was used during the procedure." The pilot's medical records (for the first 24 hours) at the admitting hospital were reviewed by the National Transportation Safety Board's Medical Officer, and there was no documentation of any cocaine use for any medical treatment or procedures. There was no notation in the hospital records as to when the CID blood sample was taken, though the records did document several hours of medical treatment prior to 2200. The ear, nose, and throat (ENT) surgeon that examined the pilot approximately 3 hours after the accident asserted that "no cocaine was used, in any form, during the time that I was involved with [the pilot's] care." The pilot asserted that "I have never taken cocaine - that I know of - in the past, and am POSITIVE that I did not take any the day of the wreck." ADDITIONAL INFORMATION The aircraft wreckage was released to a representative of the owner's insurance company on April 26, 2004.
the loss of engine power due to the failure of the engine ignition system's single-drive dual-magneto, and the magneto's improper installation by unknown maintenance personnel. Contributing factors were the improper installation of the magneto by unknown maintenance personnel, the lack of suitable terrain for a forced landing, and the dark night light condition.
Source: NTSB Aviation Accident Database
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