Crash location | Unknown |
Nearest city | Custer, SD
45.900003°N, 101.779580°W |
Tail number | N4730Z |
---|---|
Accident date | 08 Sep 2000 |
Aircraft type | Piper PA-22-108 |
Additional details: | None |
HISTORY OF FLIGHT
On September 8, 2000, at 0820 mountain daylight time, a Piper PA-22-108, N4730Z, operated by a private pilot, was destroyed when after takeoff from the Custer State Park Airport, Custer, South Dakota, it struck a tree, and subsequently impacted into the wall of a canyon. A post-crash fire ensued. Visual meteorological conditions prevailed at the time of the accident. The personal flight was being operated under the provisions of Title 14 Code of Federal Regulations Part 91. There was no flight plan on file. The pilot and pilot-rated passenger on board were fatally injured in the accident. The local flight originated at Custer, South Dakota at 0810.
A witness said that N4730Z was one of two airplanes that were going to fly by Mount Rushmore, so that the witness could have his airplane photographed against the backdrop of the mountain. The witness said that both airplane's taxied out to the end of runway 33 (4,000 feet by 50 feet, dry asphalt), and performed their preflight checks and engine run-ups. The witness said the winds at the airport were pretty much a crosswind, but seemed to favor runway 33. The witness said that N4730Z departed first. "About halfway down the runway, he got airborne. He then pushed the nose over, as if he was trying to pick up more airspeed." The witness said he keyed his microphone and asked the pilot of N4730Z, "You got trouble there?" The pilot responded, "No, just a little trouble climbing." The witness called the pilot again and said, "Turn into the wind, if you think it will help you out." The witness said that the pilot's response back was something like, "I got my hands full right now. Don't call me back." The witness said he watched the airplane until it went around the edge of a ridge beyond the end of the runway, and he lost sight of it. "A few minutes later, I saw smoke coming over the ridge."
A fire fighter pilot on the Custer State Park Airport said he watched N4730Z takeoff over the departure end of runway 33. "They were about 150 feet above the ground when he went by. He didn't gain any altitude at all. He went straight ahead and to the west." The fire fighter pilot said that the airplane wasn't climbing, and was not gaining altitude while flying into up-sloping terrain. He said the airplane passed over a ridge located about one mile off the end of runway 33. After he passed the ridge, the fire fighter pilot said he dropped out of sight. A short time after that, black smoke could be seen coming over a ridge to the northwest.
Several witnesses at a campground near the accident site saw the airplane flying along U. S. Highway 16A, heading west through the canyon. One witness said the airplane was below the tops of the mountains and trees making up the canyon walls. Another witness saw the airplane bank hard to the left. "While banking the turn, his right wing was way up and his left wing tipped ... close to [the] ground." The witness said the next thing he realized, the airplane had crashed. The witness said that the airplane's engine sounded normal.
PERSONNEL INFORMATION
The pilot held a private pilot certificate with single-engine land, instrument airplane ratings.
According to his pilot logbook, as of August 20, 2000, the pilot had recorded a total of 721.7 flying hours, 663.3 hours of which were in single-engine airplanes. The pilot's logbook showed that he had last flown N4730Z on August 20, 2000, logging 2.5 hours of flight time.
The pilot's logbook also showed that he successfully completed a biennial flight review on August 12, 2000.
The pilot held a current third class medical certificate, dated July 17, 2000. The limitations block on the certificate showed the pilot "Must wear corrective lenses."
The pilot-rated passenger held a private pilot certificate with a single-engine land rating.
According to Federal Aviation Administration aeromedical records, the pilot-rated passenger reported having 920 total civilian flying hours on July 30, 1997.
The pilot-rated passenger held a third class medical certificate, dated July 30, 1999. The limitations block on the certificate showed the pilot-rated passenger "Must wear corrective lenses for near and distant vision."
AIRCRAFT INFORMATION
The airplane was owned and operated by the pilot, and used for pleasure.
The airplane underwent an annual inspection on November 1, 1999. At the time of the annual inspection, the airframe time was 2,596.0 hours.
METEOROLOGICAL CONDITIONS
At 0753, the Routine Aviation Weather Report (METAR) at the Custer County Municipal Airport, Custer, South Dakota (field elevation 5,602 feet), 11 nautical miles from the accident site on a 245 degree magnetic heading, reported clear skies, 10 miles visibility, winds 250 degrees at 7 knots, temperature 60 degrees F, dew point 21 degrees F, and altimeter 29.95 inches of Mercury (Hg).
A fire fighter pilot at the Custer State Park Airport said that at the time N4730Z took off, the winds were out of the west, and estimated at 20 knots.
AIRPORT INFORMATION
The Custer State Park Airport (3V0) is located at the east edge of the park along Wildlife Loop Road. The field elevation is 3,980 feet. The airport operates runways 15-33. The airport exists primarily for staging aerial fire fighting operations. The park keeps two agricultural-model airplanes, loaded with water, on alert, in the event that a forest fire breaks out. Private airplanes are allowed to operate out of Custer State Park Airport with prior permission.
The airport sits in a valley. The terrain rises west of the airport. The terrain also rises off the departure ends of both runways, but especially off the end of runway 33. A 4,400-foot ridge sits approximately 1.4 miles north of the airport. A second ridge, beginning 4 miles north of the airport, forms the north walls of a canyon that proceeds northwest and then west through the park. U. S. Highway 16A runs westward along the canyon floor. The highway and the canyon walls are characterized by sharp 45 and 90 degree turns. A topographical chart of the area shows 4,200 to 4,800 foot contour lines along the second ridge.
Fire fighter pilots who stage out of the Custer State Park Airport said that they usually take off to the south on runway 15, because the terrain falls off and there is more room to climb. When they use runway 33, they turn to the northeast to east, away from the rising terrain. One pilot said that the runway [33] slopes uphill, and the winds coming off the hills to the west present difficulties to airplanes that don't have the power to climb. "We takeoff on 33 and settle over the valley there. If you keep going, you get into rising terrain and then into the canyon. If you can't climb there, it's done."
WRECKAGE AND IMPACT INFORMATION
The Safety Board on scene investigation began on September 9, 2000, at 1030.
The accident site was located in a canyon, along a 1,600 foot long, north-to-south stretch of U. S. Highway 16A, a two-lane, paved road, which begins at the east entrance to Custer State Park, and winds through the park, west to the town of Custer, South Dakota. The accident site began 5 miles west of the park's east entrance station, and 1/8 mile southwest of the park's Grace Coolidge Campground. The approximate elevation of the accident site was 4,475 feet mean sea level.
An 85-foot tall, 32 inch diameter pine tree defined the beginning of the accident site. It was located at the north end of a north-south running section of U. S. Highway 16A, approximately 15 feet northwest of the highway's edge. Several branches from the top of the tree were broken off. A 4-foot branch section was found 15 feet south of the tree's base. Several pine boughs were found on the west edge of the highway, approximately 90 feet south of the pine tree.
The airplane's main wreckage was located 270 feet south-southeast of the pine tree on a 157-degree magnetic heading. The main wreckage rested at the base of a 40 foot high, north-facing, granite wall, 70 feet east of the U. S. Highway 16A. The granite wall was a portion of the 45-degree up-sloping terrain, which made up the east side of the canyon. The main wreckage was oriented on a 135-degree magnetic heading, and rested in a 42-degree down-angle from the horizon. The main wreckage consisted of the airplane's propeller, engine, and metal tubing, which defined the frame of the airplane's cabin, fuselage, empennage, nose gear, main landing gear, and right wing.
Approximately 25 feet north of the main wreckage, two small pine trees had broken branches approximately 20 to 25 feet up from the bases. Several broken branches, approximately 7 to 10 feet long and 6 inches in diameter, were found resting on the slope west of the main wreckage. The branches were charred.
Approximately 20 feet up the granite wall from where the wreckage rested, was an impact scar. The scar was approximately 3 feet long and 2 feet wide. Several parallel-running vertical gouges in the granite, with embedded pieces of aluminum, were observed in the impact scar.
The airplane's propeller was broken off at the flange and pinned between the engine and the granite wall. It showed torsional bending and deep chordwise gouges in the front facing metal. The leading edges of both propeller blades were heavily nicked. The propeller was charred and melted. The spinner was crushed aft and twisted counter-clockwise on the hub of the propeller. It showed flakes of granite embedded in the metal, and was charred and melted.
The airplane's engine, engine mounts, firewall and nose wheel strut were bent downward, crushed aft, and twisted to the right. These airplane parts were also charred and melted. The engine cowling and nose tire were consumed by fire.
The airplane's cabin, to include the seat frames, instrument panel, control yoke columns and rudder pedals, were twisted left, bent downward, and were charred and melted. The windscreen, windows, seats, cabin interior wall, and fabric covering around the cabin, were consumed by fire.
The main landing gear legs were bent downward and charred. The main gear tires and wheel brakes were consumed by fire.
The airplane's left wing was broken aft and downward at the root. The remains of the wing rested uphill, east of the cabin section. The spars, most of the ribs, the left aileron, and all of the fabric covering, were consumed by fire. The wing struts were broken aft, charred and melted. Control cables to the left aileron were intact and charred. Flight control continuity to the left aileron was confirmed.
The airplane's right wing frame remained attached to the cabin frame. It was crushed aft along the inboard leading edge, and buckled upward at mid-span. The spars and ribs were charred and melted. The fabric, covering the wing and right aileron, were consumed by fire. The right wing struts were bent and broken aft, charred, and melted. Control cables to the right aileron were intact and charred. Flight control continuity to the right aileron was confirmed.
The metal tubing, composing the frame of the aft fuselage and the empennage, was buckled aft and twisted left 43 degrees, charred and melted. The fabric covering to the fuselage and empennage was consumed by fire. Flight control continuity to the elevator and rudder was confirmed.
An examination of the airplane's engine, engine controls, and other airplane systems revealed no pre-impact anomalies.
MEDICAL AND PATHOLOGICAL INFORMATION
An autopsy of the pilot was conducted by the Custer County Medical Examiner, at the Rapid City Regional Medical Center, Rapid City, South Dakota, on September 9, 2000.
The results of FAA toxicology testing of specimens received from the pilot showed the presence of 0.85 (ug/ml) cyanide in the blood. Normal blood cyanide concentrations are less than 0.15 ug/ml, while lethal concentrations are greater than 3 ug/ml.
FIRE
The up-sloping hill, rock walls, and trees on the east side of the canyon, in the vicinity of the airplane's main wreckage, showed heavy fire damage. A 90- foot wide burned area of trees, rocks, and brush, began 27 feet east of the road's edge, and extended up the slope of the hill, past the main wreckage, to the hill's crest.
Fire fighters from the park's nearby fire station arrived at the scene minutes after the crash occurred. Fire fighting tanker airplanes from nearby Custer State Park Airport made several water drops on the fire. According to park fire fighters, the fire was contained within minutes and less than an acre of land was damaged.
ADDITIONAL INFORMATION
The PA-22-108, Piper Colt Owner's Handbook lists in Section 1 under Performance, the rate of climb as 610 feet per minute. In Section 4, a chart titled "Climb Speeds and Rates vs. Standard Altitude" is provided. Entering the chart with a density altitude of 7,001 feet provides a rate of climb of approximately 315 feet per minute.
Parties to the investigation were the Federal Aviation Administration Flight Standards District Office, Rapid City, South Dakota, the New Piper Aircraft, Incorporated, and Textron Lycoming.
The airplane wreckage was released to the South Dakota Game, Fish, and Parks Department, Custer State Park, Custer, South Dakota.
The pilot not maintaining clearance from the tree. Factors relating to this accident were the pilot's inadequate preflight planning and preparation, the high density altitude, the inadequate rate of climb, the pilot's improper in-flight decision to fly into rising terrain, the rising terrain, the blind canyon, and the tree.