N2404XCessna 182H · 1965

On September 12, 2011, about 2313 mountain daylight time, a Cessna 182H, N2404X, impacted the terrain about three miles southwest of Stanley, Idaho. The private pilot and his passenger received fatal injuries, and the airplane, which was owned and operated by the pilot, sustained substantial damage. The 14 Code of Federal Regulations Part 91 flight, which departed Salmon, Idaho, about 45 minutes prior to the accident, was being operated in night visual meteorological conditions. No flight plan had been filed. There was no report of an ELT signal being transmitted.

On the afternoon of the day of the accident flight, after checking weather information on the internet, the pilot called a friend of his who was also a pilot. During that phone call he discussed with the friend his plan for the flight to Salmon that afternoon with a return after dark. He then asked the friend to call Flight Service to get a briefing for the area between Caldwell and Salmon. According to his friend, after he received the briefing, he advised the pilot that there had been some reports of thunderstorms and reduced visibility due to smoke along the route. The pilot then said that he would be able to see and fly around the thunderstorms on the way up to Salmon, and the friend then reminded him that he might not be able to see them if he returned at night. The friend then suggested to the pilot that because the forecast indicated a possibility of rain and clouds at the projected time of the return flight, that he might want to stay in Salmon overnight and come home in the daylight. He also suggested to the pilot that prior to making any decision to come back at night, he should call Flight Watch and get an update on the weather.

According to two passengers, who the pilot dropped off in Salmon before he departed there for his return to Caldwell, the flight to Salmon departed Caldwell between 1830 and 1845. When the pilot reached a point near Sweet, Idaho, which is located about 25 miles northwest of Boise, he contacted Salt Lake Flight Watch for an update on the weather along the route. He first advised the flight watch technician that there was a storm about 10 miles to his east, and then asked for any other pilot reports along the route. The technician advised him that he did not have any other current reports, but that there was a convective SIGMET (Significant Meteorological Information) for the area east of Sun Valley. He also advised the pilot that his radar was showing a rain cell northeast of Boise, and that its northern edge was about 30 miles north-northeast of Boise and moving to the south. He further advised the pilot that he could probably get around the cell by deviating slightly to the north, and that he did not see anything else on the radar up in that direction at that time. He then advised the pilot that he did not have a full current weather report for Stanley, but that Stanley had been reporting calm winds and a temperature of the 18 degree C. He also advised the pilot that Salmon was reporting a visibility of 10 miles, and clear below 12,000 feet.

The pilot then continued on toward Salmon, but, according to the two passengers, he had to make a significant deviation to the north to avoid a big storm that stretched from just north of Boise to an area just south of Stanley. He then continued to deviate to the north of the direct line to Salmon in order to avoid a number of smaller storms that stretched all the way to the Salmon area. Ultimately the pilot flew a route that took him from Caldwell to Emmett, to Black Canyon, near to Double D Ranch, to Deadwood, then north of Salmon, with a right turn to approach Salmon from the northeast. The flight, which according to the passengers, had taken the pilot about 75 minutes in the past, took about 2 hours and 15 minutes, ultimately arriving in Salmon after dark. Along the route the air was bumpy most of the time, but only turbulent when the airplane was close to clouds. The flight did not pass directly through any rain, but the occupants could see storms to their east along most of the route until it turned dark. Once it turned dark, they could not see any of the storms, but the passengers stated that it was a very dark night, and that the storms were not producing any lightning.

After landing at Salmon, the pilot, his brother-in-law, and the two passengers went to a nearby firefighting command post, which was located about 10 minutes from the airport. The pilot and his brother-in-law stayed there for about 45 minutes, and then returned to the airport. According to both passengers, after they landed at Salmon, the pilot and his brother-in-law were talking about the weather, and discussing whether or not they should fly back to Caldwell that night or wait until the next morning. Neither passenger paid attention to the specifics of what the pilot and his brother-in-law were saying, but reportedly they were clearly attempting to make a decision about whether to stay or go back that night.

Once the pilot got back to Salmon, he called the friend who had assisted him with the weather information earlier in the day. He discussed the weather situation with the friend, and said that the visibility had been good at the command post, and that he could see some openings in the sky from there. He further stated that he was going to go ahead and take off, and if everything looked well he would head home via Challis, Stanley, Warm Springs, and Lowman. At that point the friend told the pilot that he thought he should just stay in Salmon overnight and fly home in the morning.

The pilot then called another friend, who was also a pilot, and had a similar conversation about the weather conditions. He told that individual that he was going to take off from Salmon, but if the visibility did not look good, he would not continue, but instead land back at Salmon. He further told this individual that if he did go, but ran into weather en route, he would return to Challis and spend the rest of the night there in the airplane.

According to recorded radar data, the pilot departed Salmon about 2230, and followed a route adjacent to Highway 93 south to Challis. At Challis he turned about 30 degrees to the right, and flew on a fairly direct line to a point about ½ mile north of Stanley Airport. During the portion of the flight from Challis to Stanley, the airplane reached an altitude of about 13,500 feet, but when the pilot reached Stanley he was at 10,500 feet (about 4,000 feet above ground level). Just after passing the north end of Stanley Airport, which is located near the intersection of State Highway 75 and State Highway 21, the pilot made a right turn of about 80 degrees to parallel State Highway 21. That turn was consistent with the routing he had mentioned to his friend earlier, as Highway 21 runs between Stanley and Lowman. But, after paralleling the highway for about 2 miles, the pilot entered a left turn with a diameter of about one mile, and remained in that turn through about 180 degrees of heading change. Then about 30 seconds after rolling out of the left turn, the airplane entered another left turn, this one much tighter than the first. The airplane then descended near vertically into the terrain at an altitude of about 6,600 feet.

According to a witness in the area, who heard but did not see the airplane, the airplane sounded as if it was circling the area at a fairly low altitude. The witness said that the engine sounded like it was running strong and smoothly, but that all of a sudden it sounded as if the pilot had applied full power. Soon thereafter, the witness heard the sound of an impact, and the sound coming from the running engine suddenly stopped.

The pilot was a 55 year old male who held a private pilot certificate with an airplane single engine land rating. He did not hold and instrument rating. At the time of the accident, he had accumulated approximately 640 hours of total flight time, of which about 520 hours was in the make and model of the airplane involved in the accident, and 105 of the hours were at night. He purchased the subject airplane in 2002, and had flown it about 35 hours in the 90 days prior to the accident. Of those 35 hours, approximately 4 were at night. His last Federal Aviation Administration Airman’s Medical, a third class, was completed on June 1, 2010.

The airplane was a 1965 Cessna 182H Skylane, with an O-470-R engine, and a McCauley D2A36C29XE two-blade propeller. Its last annual inspection was signed off on 8/8/2011, which was about one month prior to the accident. At the time of the annual inspection, the airframe had accumulated 4,951.83 hours, and the engine had accumulated 1,458.73 hours since a major overhaul. During the annual inspection the number two engine cylinder was removed for low compression. It was sent out for reconditioning, and then reinstalled on the engine.

Infrared satellite imagery revealed that the area around the accident site was under a solid cloud cover, and according to an NTSB senior meteorologist, the cloud tops in the area around the 2300 timeframe were about 21,000 feet. The meteorologist characterized the weather around the area at the time of the accident as rain showers moving from east to west over the mountainous terrain. Although low level weather radar beam readings near the accident site were blocked by mountainous terrain, both the Pocatello and Boise radar stations recorded an image of precipitation at 17,000 feet over the area of the accident between 2301 and 2303.

The 2251 recorded aviation weather surface observation (METAR) for Stanley showed calm winds, a temperature of 11 degrees C, a dew point of 07 degrees C, with an altimeter setting of 30.37 inches of mercury.

The witness that heard the airplane’s impact and called the sheriff’s office, reported that it had been raining lightly around the area most of the evening, that the area was covered by clouds, and that it was raining lightly just prior to the crash. When he went outside to look around for the airplane, it was no longer raining, but there was a very low "mist" hanging in the air that reduced the visibility and caused all the house lights to be blurred. A short while later another steady light rain began. And although National Weather Service records show that there was a full moon on that night, the witness said that because of the cloud cover and the rain it was quite dark out, and that the valley was dark and eerie because of the mist.

A review of the records of the two Direct User Access Terminal Service (DUATS) providers showed that no services were provided on the day of the accident for anyone associated with N2404X. Also, a review of the Lockheed Martin Flight Services records indicated that they had not provided an update weather briefing to the pilot during the time he was at Salmon, and that the only briefing associated with airplane N2404X was the one given earlier that day to the friend of the pilot.

About three minutes prior to the accident, the pilot flew within .5 miles of the north end of Stanley Airport. He then initiated a right turn to the northwest, followed about 45 seconds later by a continuous left turn that took the airplane about 3.75 miles west of the airport, and then back in the general direction of the airport. It was after rolling out on a heading that would have taken the airplane back toward the airport, the airplane entered the rapid descent into the terrain. A review of the Flight Guide and Airport Frequency Manual for Idaho revealed that this combination turf and dirt airstrip does not have any permanent or pilot activated runway lighting, nor does it have a rotating beacon. Another pilot, who was a close friend of the accident pilot, said that he (the accident pilot) had been into Stanley Airport before, and he thought the pilot was aware that it was not lighted.

The airplane impacted lightly forested rocky terrain. The ground itself was made up of soft dirt and a high percentage of boulders ranging in size from that of a bowling ball to about twice that size. The initial impact point was about 300 feet south of Iron Creek Road, at 44 degrees, 12 minutes, 04 seconds north, by 114 degrees, 59 minute, 30 seconds west. Although the airplane had impacted three closely spaced trees about 50 feet above the ground, its ground impact location was nearly vertical from the tree impact points. The airplane dissipated a high degree of energy upon impact, and all primary structural and engine components were torn or fractured into numerous pieces. Both wings and the entire empennage had separated from the fuselage, and the fuselage itself had been torn into more than a dozen pieces. Both wings had been torn into multiple small pieces, and the only flight controls that were still attached to a part of the wing structure were one flap and a portion of one aileron. The empennage was also torn into numerous small pieces, with the only part remaining relative whole being the left elevator, which itself was torn, buckled, and twisted. Due to the extent of the damage, no flight control continuity check was able to be performed, but all control cable points of separation displayed the uneven individual wire failure locations and broomstrawing associated with an overload failure. The engine had separated from the airframe, and the crankcase had fractured into more than two dozen pieces. The majority of the engine was found at one location, with the largest single piece being the crankshaft. The crankshaft had fractured through the crank cheek between the number 5 and number 6 connecting rod journals. The number 1 through number 5 connecting rods were still attached to their journals, and the number 1 and number 2 pistons, still lodged within their respective cylinder’s, remained attached to the small end of their connecting rods. The cylinder heads were still attached to cylinder barrels number 1 through number 4, but cylinder barrels number 5 and 6 were found without their heads attached. The side walls of cylinder barrel number 5 had been crushed inward toward each other to the extent that the barrel was nearly flat and the opposing walls were within 3 inches of touching each other. The number 5 cylinder head was not found, and no pieces clearly discernible as having come from that specific head were located. Many pieces of the airplane could only be identified as having come from either the engine or the airframe, but their exact location could not be determined.

After recovery from the accident site, the airplane was taken to the facilities of SP Aircraft in Boise, Idaho, for further examination of the engine. That examination determined that the carburetor and all of the engine accessories had separated from the engine. Both magnetos were broken into numerous pieces. Portions of one of the magnetos were not found. Both magnetos had cotter pins on their drive shafts, and neither showed any evidence of electrical arcing on the body of their coils. Five of the sparkplugs were not found, but all of the remaining plugs exhibited normal operating signatures, with no evidence of preimpact contamination or excessive lead buildup. A portion of the carburetor was located, and it was determined that the inlet screen was clear of obstructions, and the float valve seat assembly was clear of obstructions and showed no abnormal wear. The oil pump was recovered, and although damage prevented its drive shaft from rotating, the pump cavity showed normal wear signatures, and the relief valve seat was clear of obstructions or debris. Also noted was a residue of oil and two marks where the gear teeth, all of which were intact, had come in contact with the oil pump interior body wall. The oil cooler was recovered, and although it exhibited significant crushing damage, there was no evidence of any preimpact anomaly. The camshaft, which was bent in a gradual progressive arc of about 30 degrees along its length, was recovered, and its lobes and journals exhibited no indication of lubrication distress or hard particle passage. The camshaft drive gear was fractured into three pieces, but the largest section was still bolted and securely safety wired to the shaft. Of the total of 12 lifters (cam followers) in the engine, five were located. The faces of all five displayed a residue of oil, and none showed any unusual wear patterns or evidence of preimpact damage. Only a portion of the propeller governor was recovered. It showed significant impact damage, and the governor oil screen was not located. Both propeller blades were recovered. Both blades exhibited “S” bending and a slight degree of longitudinal twisting along their span. Both blades displayed numerous multi-directional scratches and a number of deep leading edge and trailing edge gouges. At the completion of the examination it was determined that no evidence had been noted of any anomaly that would have prevented the engine from achieving rated horsepower.

Due to the level of energy dissipated during the airplane’s impact with the rocky terrain, the Ada County Coroner’s Office was unable to perform a formal autopsy on the pilot. Instead, the coroner’s office completed an Anthropological Inspection and Analysis of the pilot’s remains. That analysis determined that the cause of death was blunt force trauma secondary to a high speed impact.

Although the FAA provided the Ada County Coroner’s Office a forensic toxicology samples kit, the Ada County Coroner’s Forensic Supervisor advised the FAA that they were unable to obtain any usable samples from the pilot.