Aviation Accident Summaries

Aviation Accident Summary WPR11FA050

Payson, UT, USA

Aircraft #1

N978CT

DIAMOND AIRCRAFT IND INC DA20-C1

Analysis

During the dual instructional flight, the airplane entered a spin and made numerous descending rotations before impacting at a 44-degree nose down angle onto a residential driveway. Sounds consistent with engine operation during the descent were reported by witnesses. The aircraft wreckage was located directly under a designated practice area. The floor of the practice area was 2,500 feet above ground level (agl) and the upper altitude limit was 5,500 feet agl. According to the flight school director of operations, typical work done in the high-altitude working areas included stalls, slow flight, and steep turns. Examination of the airplane wreckage revealed that the flaps were in-between the takeoff and landing position; flap deployment is consistent with slow flight or stall practice. The intention of the instructional flight was to prepare the student for his private pilot practical examination. According to records maintained by the flight school, a majority of the student pilot's flights had been with the accident instructor; however, the certified flight instructor (CFI) provided extremely little documentation on the actual performance of the student during the flight portion of his training. A similar stall and spin event occurred 2 weeks prior to the accident where the same CFI and a different student lost control of the airplane during a slow flight practice; however, in that instance, the CFI was able to recover the airplane quickly. The CFI's most recent spin training was conducted 7 years prior to the accident, although the flight school required instructors to complete a flight check every 12 months for each course of training they were approved to teach. The flight school that operated the training flight did not have a functional mechanism to track safety incidents or a well advertised way for the students or staff to anonymously report aviation safety concerns. The director of safety did not convene regular safety meetings. Flight school management did not require CFIs to create written commentary regarding each student’s performance. There was a perception by three of the four chief flight instructors that CFI proficiency flights were not encouraged, and the CFIs were discouraged from using company flight time to maintain proficiency.

Factual Information

HISTORY OF FLIGHT On November 17, 2010, at 1306 mountain standard time, a Diamond DA20-C1, N978CT, descended vertically in a spin or spiral and impacted terrain in Payson, Utah. The airplane was operated by Utah Valley University (UVU) Aviation Science Department under the provisions of Title 14 Code of Federal Regulations Part 91. The commercial pilot/certified flight instructor and a student pilot were killed, and the airplane was substantially damaged. Visual meteorological conditions prevailed, and a company flight plan had been filed. The instructional flight originated at Provo Municipal Airport, Provo, Utah, at 1245. Witnesses reported hearing and seeing the airplane descend vertically in a spiral or spin making numerous rotations before impacting the driveway of a residence. Sounds consistent with engine operation during the descent were also reported. The airplane was operating below the radar coverage area. No radio distress call was received by local air traffic control agencies or the dispatcher monitoring the Utah Valley University base frequency at Provo Airport. The certified flight instructor (CFI) had flown 28 flights with the student since January 27, 2009. The student pilot was preparing for his final (end of course) private pilot check flight. Maneuvers being practiced on this flight were stalls, slow flight, and landing pattern. The aircraft wreckage was located directly under a designated practice area (practice area D). The aircrew had called on the common base frequency and coordinated the use of high altitude practice area D. The floor of the working area is 7,000 feet mean sea level (msl), and the upper altitude limit is 10,000 feet msl. The terrain elevation is approximately 4,530 feet msl. According to the flight school Director of Operations, typical work done in the high altitude working areas are stalls, slow flight, and steep turns. PERSONNEL INFORMATION The certified flight instructor, age 34, held a commercial pilot certificate for airplane single-engine land, airplane multiengine land, instrument airplane, and a flight instructor certificate for airplane single-engine, and instrument airplane. She was issued a first-class medical certificate on August 8, 2008, with no limitations. Examination of copies of the CFI’s logbook showed that she had accumulated 869.8 hours of flight time with 512.7 hours of that as dual instruction given. During the 30 days prior to the accident she had accumulated 9.2 hours of flight time, with 8.4 of those hours as dual instruction. Within the previous 90 days the CFI had flown 4 times with the student she was instructing. She had flown 6 flights in 2003 where spins were noted as having been performed, and she had a logbook endorsement for instructional proficiency for stall awareness, spin entry, spins, and spin recovery, dated August 5, 2003. There were no other logbook entries noting that spins had been performed or practiced after August 5, 2003. The CFI had received her flight review on September 10, 2010, and flew a night currency flight on October 21, 2010; both flights were flown with the flight school's chief instructor for the private pilot curriculum. The CFI’s husband was interviewed in order to establish what her stress and fatigue levels were the day of the accident. The CFI’s husband stated that his wife had a full time job working for the City of Lindon as the finance director, was taking night classes in pursuit of a Masters Degree in Public Administration, and they had two children. During the week day she would usually flight instruct in off hours, which included lunch breaks. She attended night classes on Tuesday nights from 1800-2200. An extended family member had been helping to take care of the children and cook some of the family meals. Her regular sleep routine was to be in bed around 2230 and up around 0615. The night before the accident she was in bed at 2245, and she was up at 0615 the day of the accident. Her eating patterns were unchanged the few days prior to the accident, diet was normal, and her sleep pattern had been undisturbed. She had not complained of fatigue or any physical ailments, and she was not under any unusual stresses. The student pilot, age 25, held a second-class medical certificate and student pilot certificate dated January 5, 2009. The certificate had an instructor’s solo endorsement dated April 21, 2009, in the DA20-C1, and an instructor's cross-country endorsement dated September 4, 2009, in the DA20-C1. Examination of the student pilot’s logbook revealed that he had a total 63.7 hours of flight time (53.6 hours dual, and 10.1 hours solo). The student had flown four flights (4.8 hours) over the previous 90 days; August 27, October 2, October 12, and November 11. All four flights were with the accident CFI. Remarks in the student’s logbook state that during all four flights slow flight was practiced, and stalls were practiced on all except for the November 11 flight. Review of the student's training records indicated that the student was preparing for his final (end of stage) private pilot check flight. Training records showed that tasks on all training flights were marked with an “S”, indicating satisfactory performance of that task; however, in the remarks section of the last four flights the instructor stated that the lesson was reviewed for student proficiency. The training records did not have any additional remarks or comments by any CFI about the student’s flying performance, and none were required by the UVU Aviation Science Department. AIRCRAFT INFORMATION The two-seat, low wing, fixed gear, single-engine airplane, serial number C0078, was manufactured in 1999. It was powered by a Teledyne Continental Motors IO-240-B, 125-hp engine, and equipped with a Sensenich fixed pitch propeller. Review of the maintenance records showed that a 50-hour inspection was performed on November 1, 2010; engine time since overhaul (TSO) was 1,437.9 hours, and total airframe hours were 6,148.4 hours. The most recent maintenance was the replacement of the left and right tires on November 10, 2010, at total aircraft time of 6,167.2 hours. In a written statement the CFI who flew N978CT from 1000 to 1200 on the day of the accident said that the airplane operated normally throughout the flight. The flight lasted 1.2 hours, consisted of four stop-and-go’s, and the controls felt normal and moved freely. The UVU dispatch records, fueling log, and Invoice Out Report for N978CT indicate that the accident airplane flew twice on November 17 before the accident flight for a total of 2.6 hours, and that the airplane was fueled with 11.6 gallons of avgas just before the accident flight. The cockpit and baggage area items that were located with the airplane wreckage were inventoried and weighed; total weight in the baggage compartment was 23.9 pounds. The autopsies documented the CFI’s weight as 140 lbs, and the student’s weight as 170 lbs. The airplane’s weight and balance documents dated May 5, 2010, shows the airplane empty weight was 1,224 lbs. The calculated weight of the airplane at takeoff was 1,705 lbs, and the center of gravity (CG) was 10.93 inches aft of datum. The airplane's weight and balance was within the normal operating range as specified in the Diamond DA20-C1 Flight Manual, Supplement 4. The maximum allowed gross weight of the DA20-C1 is 1,764 lbs, and the furthest aft cg allowed is 12.49 inches. The DA20-C1 flight manual states in Section 2.9 Approved Maneuvers, that the airplane is certified in the UTILITY Category in accordance with Canadian Airworthiness Manual Chapter 523-VLA. Permissible Utility Category Maneuvers include all normal flight maneuvers and spinning. Section 4.4.16 Spinning, includes two CAUTION notes stating, “Intentional spinning is only permitted with flaps in cruise position,” and “Depending on CG and spin entry technique attempts to enter spins may develop into spiral dives. Monitor the airspeed during the first turn and recover immediately if it increases to 65 KIAS.” Another NOTE states, “Spins with aft CG may oscillate in yaw rate and pitch attitude. This has no effect on recovery procedure or recovery time.” The Flight Test Report concerning spins in the DA20 (FTR-DA20-C1-014) was provided by Diamond Aircraft. The report documents a series of 150 spin entries performed with the DA20-C1 to include full aft CG with flaps at cruise, takeoff, and landing position. The specific conclusions of the report state, “It has been shown by test that the DA20-C1 Katana is able to recover from a 6-turn or 3-second spin, whichever takes longer, with flaps retracted, or from a 1-turn or 3-second spin, whichever take longer, with flaps extended, within an additional 1 1/2 turns. For both the flaps retracted and flaps extended conditions, the positive limit maneuvering load factor and the airspeed limit are not exceeded during spin recovery when the flaps are retracted during the spin recovery. Note that the DA20-C1 contains a placard stating ‘All aerobatic maneuvers, except for intentional spinning which is permitted with flaps UP only, are prohibited.’ It is Impossible to obtain an unrecoverable spin with any use of controls at the entry to or during the spin, as showed by over 150 successful spins completed during this test program.” The Flight Test Report stated that the utility category aircraft exhibited a very smooth conventional spin with yaw rates of 125 degrees per second and height loss of 250 feet per turn at full aft CG. These parameters relate to a 5,200 feet per minute rate of descent. The DA20-C1 Flight Manual, section 3.3.6, Recovery from Unintentional Spins, states the following: 1. Throttle Idle 2. Rudder Fully applied to the opposite direction of spin 3. Control Stick Ease forward 4. Rudder Neutral after rotation has stopped 5. Wing Flaps Cruise 6. Elevator Pull cautiously Bring airplane from descent into level flight position. Do not exceed maximum permissible speed (Vne). The DA20-C1 is equipped with a four-point safety belt. The latching buckle design utilizes a lock cover similar to that used by commercial airline passenger restraints. Anecdotal comments by two flight instructors at UVU imply that they themselves or their students have experienced unintentional release of the safety belt buckle. The Safety Board investigator-in-charge (IIC) examined the seating, safety harness, and crew position in the DA20 and found it possible to unintentionally release the buckle by grazing a jacket sleeve across the buckle face. The UVU Director of Operations (DO) was made aware of this fact and said he would document any future reports of an unintentional buckle release. A conversation with the UVU Director of Operations a few months after the accident indicated that there had been no reports of an unintentional buckle release. Diamond Aircraft was made aware of the finding and reported that none of their other operators had experienced this issue. Diamond stated that they conducted some tests and noted that if the harness is properly adjusted per the Aircraft Flight Manual (AFM) the buckle is not subject to inadvertent opening. WRECKAGE AND IMPACT INFORMATION The aircraft wreckage was located between two houses on hard compacted driveway ground. The student pilot was positioned in the left seat with his seat harness and shoulder straps buckled. The CFI was positioned in the right seat, her lap belt and shoulder straps were not buckled or positioned around her body. The aircraft was oriented facing a magnetic bearing of 041 degrees, with its nose and engine collapsed on the ground, fuselage elevated at a 30-degree angle, and the tail was broken off at a location 4 feet forward of the tail cone end. The wings remained attached to the fuselage at the wing root area. The canopy glass had shattered and was distributed in a fan like pattern 10-15 yards forward of the cockpit. The nose wheel had collapsed rearward and right, into the cockpit area. Both main landing gear were displaced aft and upward, the left main strut was displaced farther aft than the right main strut. The right wing had fractured along a diagonal line from the leading edge to the trailing edge beginning 4 feet inboard from the wing tip. Damage to the left landing gear main mount, left side of the cockpit, and left wing tip are consistent with the left-hand rotation of the aircraft about the vertical axis and vertical impact forces. Flaps and ailerons were attached to both wings; elevator and rudder were attached to their hinges on the tail. Control continuity was established from the rudder pedals to the rudder, and from the control sticks to the elevator and ailerons. The flap jackscrew was removed and measured 0.5-inch extension, which according to the Diamond Aircraft technical representative, corresponded to a flap extension between the landing and takeoff positions. The two bladed wood-composite propeller remained attached to the engine propeller flange. One blade was separated at the hub and in splinters; the other blade was undamaged. The spinner was crushed flat on one side. The angle measured between the spinner’s flat crush face and the longitudinal axis of the airplane was approximately 45 degrees. The engine oil pan was crushed; the starter and both left and right magnetos separated from the engine. The exhaust manifolds remained attached to the cylinders and exhibited damage consistent with plastic deformation. The spark plugs exhibited normal operating signatures in accordance with the Champion aviation check-a-plug chart. Blue liquid with a petroleum odor was observed in the fuel manifold valve assembly. The engine was rotated by hand and thumb compression was detected within all cylinders, and the valves moved in sequence. Nothing was identified that would have precluded the normal operation or function of the airplane’s engine or flight controls. MEDICAL AND PATHOLOGICAL INFORMATION An autopsy was performed on both the CFI and student pilot on November 18, 2010, by the State of Utah Medical Examiner. The autopsy findings for both pilots included blunt force injuries of the head, torso, and extremities. The Safety Board IIC conducted a follow-up phone interview with the Utah State Medical Examiner concerning the injury patterns between the CFI and student pilot. The Medical Examiner stated that neither victim had definitive marks indicating the presence of a lap belt or shoulder harness; however, both victims exhibited similar skin discolorations across their clavicles, and the injuries to their extremities and torsos were similar. Forensic toxicology was performed on the specimens from the CFI and student pilot by the FAA Bioaeronautical Sciences Research Laboratory CAMI, Oklahoma City, Oklahoma. The toxicology report for the CFI stated negative findings for carbon monoxide, cyanide, or ethanol. Ibuprofen was detected in urine. The toxicology report for the student pilot stated negative findings for carbon monoxide, cyanide, ethanol, and none of the specified drugs were detected. ORGANIZATIONAL AND MANAGEMENT INFORMATION Utah Valley University (UVU) Department of Aviation Science operates as a Federal Aviation Regulation (FAR) Part 61 flight training school, and offers flight training from the private pilot level through the commercial multi-engine pilot certificate, instrument ratings, and certified flight instructor certificates. The flight training staff consists of approximately 50 certified flight instructors that are employed on a part time basis and 4 chief flight instructors that are employed full time. The school operates 15 Diamond Katana DA20’s, 6 Diamond Star DA40’s, and 4 Diamond Twin Star DA42’s. The main facility is located at the Provo Municipal Airport, and the organization performs its own maintenance on all the airplanes. The Aviation Science Program offers the opportunity for students to earn Associate and Bachelor of Science in Aviation Science degrees. Approximately 2,000 students are enrolled in the program. A majority of those students are enrolled in the on-line program. About 250 students are enrolled locally taking flight instruction, with 90-100 students v

Probable Cause and Findings

The pilots' failure to maintain adequate airspeed during a slow flight maneuver that resulted in a stall and spin, and the flight instructor’s delayed or improper remedial actions to recover from the spin. Contributing to the accident was the flight school’s inadequate safety program.

 

Source: NTSB Aviation Accident Database

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