Crash location | 45.044166°N, 92.020278°W |
Nearest city | Boyceville, WI
45.043574°N, 92.041015°W 1.0 miles away |
Tail number | N658CD |
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Accident date | 05 Aug 2006 |
Aircraft type | Cirrus Design Corp. SR22 |
Additional details: | None |
HISTORY OF FLIGHT
On August 5, 2006, at 1140 central daylight time, a Cirrus Design Corp. SR22, N658CD, received substantial damage on impact with terrain during approach to runway 26 (3,300 feet by 60 feet, asphalt) at Boyceville Municipal Airport (3T3), Boyceville, Wisconsin. Visual meteorological conditions prevailed at the time of the accident. The 14 CFR Part 91 instructional flight was not operating on a flight plan. The pilot received serious injuries. The certified flight instructor (CFI) and the passenger received minor injuries. The flight originated from Duluth International Airport, Duluth, Minnesota, at 1015, and was en route to Chippewa Valley Regional Airport (EAU), Eau Claire, Wisconsin.
The pilot had recently purchased the accident aircraft and was receiving Cirrus Factory Authorized Training, which was provided by University of North Dakota Aerospace instructors. According to the CFI, pilots receive, on average, three days of training which is included in the purchase price. The accident pilot made the decision to receive four days of training rather than three days.
The CFI reported that on the last day of training the airplane was en route towards EAU when he announced a simulated oil annunciator light during cruise flight. The pilot selected a course to the nearest airport, 3T3, which was less than five nautical miles away from their position. The CFI then pulled the throttle to idle to simulate an engine failure. The pilot descended into a left hand pattern for runway 26 at best glide speed and was at approximately 1,000 feet above ground level (AGL) "abeam the runway numbers." The CFI reported that the airplane was "stabilized at best glide airspeed on base" when the audible 500 feet AGL warning from the terrain awareness warning system sounded. The CFI stated that the pilot banked "steeply" to the left and when the airplane exceeded 30 degrees of bank he verbally warned the pilot. The pilot "banked [the airplane] steeper," the stall horn sounded, and the left wing "dropped." The CFI then "grabbed the controls to prevent [the airplane] from entering a spin" and applied full power. The CFI reported that the airplane was "losing altitude in the stall with the left and right wing alternately dropping." The airplane subsequently impacted terrain, coming to rest upright and facing "back in the direction from which [the airplane] had come."
The CFI stated in his accident report that "the aircraft owner/pilot in training had previously performed all elements correctly: stalls, traffic patterns, and power off landings. They had discussed bank angle limits in traffic patterns. While likely being caught up in the maneuver at hand, the pilot lost sight of the overall picture and jeopardized safety to complete the task. With low flight time (approximately 60 to 70 hours, all in a Cessna 172), the pilot did not correlate all tasks and acted unpredictably."
PERSONNEL INFORMATION
Pilot logbook records indicate that the pilot began flight training on October 30, 2004, and after accumulating a total flight time of 60.8 hours, he was issued a private pilot certificate with a single-engine land rating on June 22, 2006, using a Cessna 172 for the flight portion of the examination. Prior to issuance of a pilot certificate, he accumulated 4 hours of flight time in Mooney 20F airplanes and the remainder of his flight time in Cessna 172 airplanes. Following the issuance of his pilot certificate, he accumulated an additional 4.5 hours of flight time prior to beginning Cirrus SR22 training and receiving a 14 CFR Part 61.31(f) high performance airplane endorsement on August 3, 2006. The endorsement was signed by the CFI involved in the accident and the flight had been flown in the accident airplane.
The CFI stated that he attended the University of North Dakota (UND) in fall 1999 and began flying in January 2000. He graduated from UND in spring 2000, with a commercial pilot certificate, multiengine airplane rating, CFI certificate with an instrument rating. He was hired by UND as a CFI and began private instruction on Cirrus airplanes in "late" June 2006, after receiving training on Cirrus airplanes. He accumulated a total flight time of 915 hours, of which 62 hours were in Cirrus SR22 airplanes.
AIRCRAFT INFORMATION
The 2005 Cirrus SR22, airplane was registered to the pilot on August 2, 2006, after it had been registered to a previous owner. The airplane was then purchased by the current owner through the Cirrus Certified program.
The airplane was equipped with AMSAFE, Incorporated inflatable four-point restraint safety belts with an intergraded airbag device. The system was installed under a Federal Aviation Administration Final Special Condition and issued as part of the type certificate basis for the airplane, as modified by AMSAFE, Incorporated.
The rear seat passenger, who was also the pilot's son, accompanied the pilot through all aspects of Cirrus SR22 flight training. The passenger stated that he accumulated a total flight time of approximately 55 hours in Cessna 172 airplane(s) towards a private pilot certificate and he was scheduled to take the exam after his return from Duluth, Minnesota. While in Duluth, the passenger flew the Cirrus SR22 from the left seat and stated the difficulties in transitioning to the Cirrus SR22 included maintaining airspeed. He said that it's not like a Cessna 172 as it gets fast. The Cirrus is unlike a Cessna 172 where you can feel an impending stall where it gets "mushy," and you have to be on top of the gauges. He added that with getting used to all the electronics is a lot to learn over three days.
WRECKAGE AND IMPACT INFORMATION
The airplane was located approximately 350 feet to the right of the approach end for runway 26 in a bean field. The main wreckage, which consisted of the fuselage, wings, empennage, and engine was at the western edge of a 150 foot long ground scar oriented on a 270 degree heading. There were three depressions along the length of the ground scar. The eastern end of the ground scar was near an area of debris from the left wing tip and pieces of the upper wing skin, followed by a second depression approximately 50 feet from the first ground scar along the 270 degree heading. The second depression was approximately 10 feet by 15 feet and contained pieces of engine cowling. Adjacent to the second depression were tree branches cut approximately 60 degrees relative to horizontal. The western most depression contained the main wreckage oriented on a tail to nose heading of approximately 150 degrees with the attached engine, fuselage, wings, and empennage.
The left wing (the wing is a one piece wing) exhibited wrinkles oriented from the inboard leading edge, forward of the fuel cap, to the outboard direction approximately 3/4 chord at a 45 degree angle relative to the wing chord. The left wing tip was separated from the wing which was fractured about 8 feet inboard from the wing tip. The left wing also exhibited aft wise deformation. The right wing was undamaged. Both wing flaps were attached to their wings.
The fuselage was separated from the wing assembly and was resting on its right side. The fuselage separation traversed the bottom of the A-pillars to the left cabin door lower aft corner, across the floor between the front and rear seats, and to the lower aft corner of the right cabin door.
The nose landing gear was fractured from the gear mount at the upper end of the strut. The nose landing gear tire and wheel were attached to the strut. The left main landing gear was attached to the wing. The right main landing gear was separated approximately midpoint of the axle fitting and the strut upper end fitting. The lower section of the right main landing gear strut was separated from the wing. The right main landing gear tire and wheel assembly remained attached to the lower section of the separated strut.
The left and right front seats were attached to the spar tunnel. The left and right front airbag seatbelts were deployed. The left front energy absorption module exhibited crushing damage across its leading edge from its left and right comers. The crushing extended across the top, from front to rear, approximately 2 inches aft from the left front corner and right front corner and approximately 6 inches aft across the middle. The left front energy absorption module's leading edge was approximately 2-3/4 inch thick. The right front energy absorption module exhibited crushing damage across its leading edge from its left to right corner. The crushing extended across the top from front to rear approximately 3 inches aft from the left front corner to approximately 6 inches aft front he right front corner. The right front energy absorption module's leading edge was measured to be approximately 2-3/4 inches thick. Both rear seats were attached to the floor. The foam core of the right rear seat exhibited crushing in the center of the leading edge. The leading edge of the foam core was crushed to approximately a 1/2 inch thickness.
Photos of the accident site, the firewall shield, and engine mount frame are included in the docket of this report. The metal firewall shield was wrinkled and both bottom firewall-to-engine frame mounts were damaged. The bottom left firewall-to-engine mount was deformed outboard, and the left mount was crushed inward deforming each side of the mount to the outboard and inboard direction, respectively. The engine frame was deformed to the right approximately 5-10 degrees. The top left engine frame tube was fractured through near the firewall mount. The right engine frame tube that attaches to the nose wheel mount was fractured through. All of the engine mount bolts were intact and not fractured.
A site soil investigation of the accident site was performed on three contact points along the ground scar the results of which were documented and are available in the docket of this report. The soil investigation also provided Dynamic Cone Penetrometer (DCP) tests with a California Bearing Ration (CBR) correlation. The grain size distribution for the soil samples indicated a fine to medium sand with some silt. The percent passing the #200 sieve ranged from 29.1 percent to 40.9 percent.
Contact point 2A consistent with initial impact point had a CBR of 4.3, a moisture percentage of 8.8%, and a dry density of 105.7 pcf. The average values for contact point 2A were a DCP of 29.2 mm/blows and CBR of 6.
The second contact location, point 2B, consistent with a nose impact, had a CBR of 10.0, a moisture percentage of 5.0%, and a dry density of 109.8 pcf. The average values for contact point 2B were a DCP of 18.8 mm/blows and CDR of 10.
The third contact location, point 3A, was the resting location of the airplane, point 3A, had a CBR of 7.7 and a moisture percentage of 9.5%, and a dry density of 102.8 pcf. The average values for contact point 3A were a DCP of 15.2 mm/blows and CBR of 13.
The Hobbs meter indicated 61.1 hours.
ADDITIONAL INFORMATION
AMSAFE, Inc., Avidyne, Cirrus, Continental Motors, and the FAA were parties to the investigation.
The pilot's failure to maintain adequate airspeed and the certified flight instructor's delayed remedial action and inadequate supervision of the flight training, which resulted in an inadvertent stall during a base to final turn to the landing runway. An additional cause was the pilot's lack of total experience in the Cirrus SR22. A factor in the accident was the low altitude at which the stall occurred.