NTSB CAROL · Event
Event CHI06FA232
Registry · N133BH
FAA Aircraft Registry record.
Make / Model
HUGHES 369HS
Year of manufacture
1969 · 37 years old at event
TCDS
H3WE · MD HELICOPTERS INC (MDHI)
Engine
ALLISON 250 SER 317HP (317 hp)
Seats / Engines
4 seats · 1 engine
Last airworthiness date
19820924
ADS-B equipped
Yes — Mode-S A08677
Registrant of record
BROWN HELICOPTER INC
Source: FAA Aircraft Registry (releasable master file).
Aircraft involved
Probable cause & findings
The pilot's failure to maintain aircraft control during the circling approach and his failure to perform a missed approach when the airplane was no longer in a position to land using normal flight maneuvers. Contributing to the accident was the pilot's decision to operate below the approach's authorized minimum descent altitude (MDA) before having the airport/runway environment visible. Additional factors were the low cloud ceiling and visibility.
Factual narrative
HISTORY OF FLIGHT
On August 14, 2006, at 0918 eastern daylight time (all referenced times are eastern daylight time), a Piper PA-23-250 Aztec, N133BH, operated by Spring City Aviation, Inc., Waukesha, Wisconsin, was destroyed during an explosion and ground fire following an in-flight collision with terrain while attempting to land at the Chippewa County International Airport (CIU), Sault Ste. Marie, Michigan. Instrument meteorological conditions (IMC) prevailed at the time of the accident. The instructional flight was operating under the provisions of 14 Code of Federal Regulations (CFR) Part 91 while on an instrument flight plan. The flight instructor, dual student, and two passengers were fatally injured. The flight departed the Waukesha County Airport (UES), Waukesha, Wisconsin, at approximately 0711. At 0624, the flight instructor contacted Green Bay Automated Flight Service Station (AFSS) to file an instrument flight rule (IFR) flight plan and to obtain a weather briefing. The planned route of flight was to depart UES, then proceed direct to the Escanaba (ESC) VHF Omni-directional Range (VOR), and then direct to the Sault Ste. Marie (SSM) VOR. The SSM VOR was an initial approach fix for the destination airport. The requested cruise altitude was 11,000 feet mean sea level (msl). The briefer told the flight instructor that marginal visual meteorological conditions (VMC) prevailed along the route of flight, with areas of IMC near Escanaba, Michigan, and Manistique, Michigan. The briefer told the pilot that the forecast weather near the destination airport was VMC, with periods of reduced ground visibility of 5 miles due to light rain and mist. The destination forecast called for scattered clouds between 2,000 and 2,500 feet above ground level (agl) and an overcast ceiling at 10,000 feet agl. At 0711, the accident airplane was cleared for departure from UES. At 0713, the pilot established radio communications with the Milwaukee Departure Control. The flight was cleared to climb to 11,000 feet msl and to fly direct to ESC VOR, then to continue as filed. At 0729, the airplane was handed off to Chicago Air Route Traffic Control Center (ARTCC) who verified that the airplane was flying direct to ESC VOR. At 0741, the airplane was handed off to Minneapolis ARTCC. At 0837, the pilot requested and was cleared to descend to 7,000 feet msl. At 0840, the pilot reported having the current weather at the destination airport (CIU). At 0848, the airplane was handed off to Toronto ARTCC. At 0849, the pilot established radio communications with Toronto ARTCC and reported being level at 7,000 feet msl. Toronto ARTCC cleared the airplane to descend to 5,000 feet msl and inquired which instrument approach procedure the pilot wanted. The pilot requested the VOR-A approach into CIU, landing runway 27. At 0855:41 (hhmm:ss), Toronto ARTCC cleared the airplane for the VOR-A approach into CIU and instructed the pilot to report when established inbound on the approach. At 0859:37, the airplane was cleared to descend to 3,000 feet msl. At 0908:26, the pilot reported crossing the SSM VOR inbound on the approach. At 0908:34, Toronto ARTCC told the pilot to change to the CIU Unicom frequency and to cancel his flight plan after landing. At 0908:43, the pilot acknowledged the clearance and stated "I'll cancel on the ground, still IMC." No additional communications were received from the accident airplane. According to aircraft radar track data, the accident airplane tracked the 218-degree radial inbound to CIU. The airplane descended below the approach's authorized minimum descent altitude (MDA) of 1,260 feet msl about 2.6 miles northeast of the airport. The airplane then leveled off at 1,085 feet msl until crossing over the intersection of runway 9/27 and runway 16/34. The airplane then made a left turn to the east, and paralleled runway 27 about 600 feet south of the runway at 985 feet msl. At 0916:29, the last radar return associated with the accident airplane was recorded at 985 feet msl, about 0.5 miles east of the runway 27 threshold. The airplane impacted immediately adjacent to a prison perimeter fence located north of extended runway centerline, and about 725 feet north of the last recorded radar return. Numerous witnesses reported seeing the airplane traveling eastbound approximately 150 and 200 feet agl, and then perform a left turn back toward airport before impacting nose first into the terrain. Several of those witnesses reported that the airplane reached a bank angle of approximately 90 degrees during the turn.
PERSONNEL INFORMATION
Flight Instructor -- According to Federal Aviation Administration (FAA) records, the flight instructor, age 23, held a commercial pilot certificate with single and multi-engine land airplane, and instrument airplane ratings. He also held a flight instructor certificate with single and multi-engine airplane, and instrument airplane ratings. His last aviation medical examination was completed on October 13, 2005, when he was issued a first-class medical certificate with no restrictions or waivers. The flight instructor's most recent logbook entry was dated August 12, 2006, at which time he had accumulated 998.3 hours total flight time. Of that total, 937.5 hours were in single-engine airplanes and 60.8 hours were in multi-engine airplanes. He had accumulated 134.5 hours at night, 35.5 hours in actual instrument conditions, and 46.1 hours in simulated instrument conditions. He had flown 32.5 hours in a Piper PA-23-250. The flight instructor had provided 572.4 hours of flight instruction, of which 564.4 hours were in single-engine airplanes and 8.0 hours were in multi-engine airplanes. During the 30-day period prior to the accident, the flight instructor had flown 62.6 hours total flight time. Of that flight time, 57.9 hours were in single-engine airplanes and 4.7 hours were in multi-engine airplanes. The 4.7 hours of multi-engine time were accumulated in the accident airplane. He had flown 0.2 hours at night and 3.5 hours in actual instrument conditions, including 8 instrument approaches. An additional 10 instrument approaches were logged without any corresponding instrument time for the particular flight. During the 90-day period prior to the accident, the flight instructor had accumulated 247.5 hours total flight time. Of that flight time, 239.3 hours were in single-engine airplanes and 8.2 hours were in multi-engine airplanes. A total of 4.7 hours were flown in the accident airplane. He had flown 4.2 hours at night and 9.6 hours in actual instrument conditions, including 21 instrument approaches. An additional 57 instrument approaches were logged without any corresponding instrument time for the particular flight. During the 6-month period prior to the accident, he had flown 488.5 hours total flight time. Of that flight time, 464.4 hours were in single-engine airplanes and 24.1 hours were in multi-engine airplanes. A total of 17.6 hours were flown in the accident airplane. He had flown 30.8 hours at night and 22.5 hours in actual instrument conditions, including 47 instrument approaches. An additional 95 instrument approaches were logged without any corresponding instrument time for the particular flight. Dual Student -- According to FAA records, the dual student, age 30, held a private pilot certificate with a single-engine land airplane rating. He was not instrument rated. His last aviation medical examination was completed on September 12, 2005, when he was issued a third-class medical certificate with no restrictions or waivers. The dual student's logbook was not recovered and is presumed to have been destroyed during the accident. His private pilot certificate was issued on May 24, 2006, at which time he had accumulated 70.8 hours total flight time. Of that flight time, 18.4 hours were as pilot-in-command, 52.4 hours were dual-instruction received, 3.8 hours were at night, and 3.5 hours were instrument instruction. According to information provided by Spring City Aviation, Inc., the dual student completed his private pilot training using their airplanes and flight instructor staff. After receiving his private pilot certificate, the dual student had received additional instruction toward a tailwheel endorsement. Additionally, family members indicated that he was pursuing multi-engine instruction. However, according to available information, the dual student had not received any flight instruction in a multi-engine airplane prior to the accident flight.
AIRCRAFT INFORMATION
The accident airplane was a twin-engine 1966 Piper PA-23-250 Aztec, s/n 27-3198. The airplane incorporated a low-wing design with a retractable tricycle landing gear, and could accommodate six occupants. The airplane was powered by two Lycoming IO-540-C4B5 six-cylinder, fuel-injected, reciprocating engines. The 250-horsepower engines provided power through Hartzell HC-E2YK-2RBS two-bladed propeller assemblies. The propellers were a hydraulically operated, constant speed design with feathering capability. According to the maintenance logbooks, the most recent inspection was completed on June 16, 2006, at 8,933.7 total airframe hours. The airframe, engine and propeller logbooks noted a recording hour meter of 1,806.4 hours at that 100-hour inspection. Both engine assemblies were overhauled on November 19, 1996, and installed on the accident airplane on February 27, 1997. At the time of the last inspection, the left engine, s/n RL-6274-48, and right engine, s/n RL-3895-48, had accumulated 8,933.7 hours total time and 2,035.4 hours since overhaul. At the time of the last inspection, the left propeller, hub s/n BP2277, and the right propeller, hub s/n BP2219, had accumulated 1,796.1 hours since overhaul. On April 27, 2006, tests on the static system, altimeter system, automatic pressure altitude reporting system, and transponder were completed and performed as required. A review of the airframe, engine and propeller records found no history of unresolved airworthiness issues.
METEOROLOGICAL INFORMATION
The Chippewa County International Airport (CIU) was equipped with an automated weather observing system (AWOS). The local weather conditions were continually broadcast and accessible using a telephone or radio. The following weather conditions were reported by the CIU AWOS: At 0835: wind 180 degrees at 5 knots; visibility 3 miles; scattered clouds at 900 feet agl, sky overcast at 3,500 feet agl; temperature 17 degrees Celsius; dew point 15 degrees Celsius; altimeter setting 29.69 inches of mercury. At 0855: wind 210 degrees at 4 knots; visibility 2 miles; sky overcast at 500 feet agl; temperature 17 degrees Celsius; dew point 15 degrees Celsius; altimeter setting 29.69 inches of mercury. At 0915: wind 210 degrees at 4 knots; visibility 1-1/4 miles; sky overcast at 300 feet agl; temperature 17 degrees Celsius; dew point 16 degrees Celsius; altimeter setting 29.69 inches of mercury. At 0935: wind 210 degrees at 6 knots; visibility 1-1/2 miles; broken ceiling at 200 feet agl, overcast ceiling at 1,000 feet agl; temperature 17 degrees Celsius; dew point 16 degrees Celsius; altimeter setting 29.69 inches of mercury.
AIDS TO NAVIGATION
At the time of the accident, the flight had been cleared for the VOR-A instrument approach procedure into CIU. The principal navigational fix for the approach procedure was the Sault Ste. Marie (SSM) VOR, which was located about 11.3 nautical miles (nm) northeast of CIU. The SSM VOR facility was also equipped with distance measuring equipment (DME). The approach procedure required the pilot to cross the VOR at a minimum altitude of 3,200 feet msl. Upon crossing the VOR inbound, the pilot was to track the 218-degree radial and permitted to descend to an altitude of 2,400 feet msl. The final approach fix was at TENNY intersection, located 6.4 nm from the VOR on the 218-degree radial. Upon crossing TENNY intersection, the pilot was permitted to descend to the minimum descent altitude (MDA) of 1,260 feet msl. The approach plate noted that the airport elevation was 800 feet msl. The specified missed approach point was 11.3 nm from the VOR. The approach procedure required a minimum visibility of 1 mile to continue with a circling maneuver to runway 9/27 or 16/34. The pilot had to maintain visual contact with the airport environment during the circling maneuver and landing. If visual contact was lost, the pilot was to execute a missed approach. The missed approach procedure was to initially climb to 1,500 feet msl, then make a climbing right turn to 2,400 feet msl, then join the 218-degree radial and hold at TENNY intersection.
AIRPORT INFORMATION
The Chippewa County International Airport (CIU) was located about 15 nm south of Sault Ste. Marie, Michigan. The airport had two runways: 9/27 (5,000 feet by 75 feet, asphalt) and 16/34 (7,201 feet by 200 feet, concrete). Runway 16/34 was closed for service at the time of the accident. A notice to airmen (NOTAM) was issued for the runway closure and the flight instructor received the closure information during his preflight briefing. The airport elevation was listed as 800 feet msl. FAA runway obstruction data indicated that there were trees about 51 feet tall located 1,800 feet off the approach end of runway 27. The trees were located 200 feet left of the runway centerline. A 1.9-degree slope was required to clear the trees. Runway 27 was equipped with 4-light precision approach path indicator (PAPI) system.
WRECKAGE AND IMPACT INFORMATION
The airplane impacted immediately adjacent to a prison perimeter fence located about 0.5 miles east of the runway 27 threshold. The fence sustained minor damage, remaining upright. The minimal damage to the fence and the absence of any discernable lateral ground markings was consistent with a near vertical impact. A majority of the airframe was destroyed during the post-impact ground fire. The fuselage and main cabin were destroyed by fire. All combustible materials were consumed during the fire. The only discernable cabin components were of steel construction. The instrument panel and its associated components exhibited fire and impact damage. An altimeter was recovered and exhibited fire and impact damage. The altimeter pressure window was selected on 29.65 inches of mercury. No gyro-equipped instruments were found. All of the engine quadrant controls were in the full-forward position. The landing gear selector was partially consumed and separated from its normal subpanel position. The landing gear handle was in the down position. The nose landing gear was displaced aft into its wheel well and its strut was fractured; however, the actuator inner rod was extended, consistent with a gear down position. The flap handle assembly was partially melted and its position could not be determined. The flap actuator inner-shaft extension measured approximately 5.25-inches, consistent with a partial flap extension. The fuel control levers were positioned on the outboard fuel tanks. The cowl flaps were in the open position. The alternate air controls were in the closed position. The position of the fuel cross feed lever could not be determined due to fire and impact damage. Both wings were destroyed by fire. The melted remains of the ailerons and flaps were located in their appropriate positions. The aileron balance weights were located, but their respective attach points were consumed by fire. The aileron balance cable remained attached to both bellcranks. Both control cables remained attached to their respective bellcranks and were continuous to the cockpit control wheel assembly. The aileron bellcranks were fire damaged and separated from their attachment structure. The main landing gear were displaced aft of their normal positions. Both landing gear actuators were fire and impact damaged; however, the actuators were extended, consistent with a gear down position. The empennage structure was the only airframe component not completely destroyed by fire. The vertical stabilizer and horizontal stabilator exhibited thermal and impact damage. The rudder remained attached to the vertical stabilizer. The rudder and stabilator control cables remained connected to their respective bellcranks and were continuous to the cockpit control wheel assembly. The stabilator trim tab was partially separated from the stabilator and was in a neutral trim position. The left engine was resting upright on the ground and remained partially attached to the airframe. The entire engine assembly exhibited thermal damage. The engine was rotated by turning the propeller flange. Crankshaft continuity was confirmed to all engine cylinders, rear gear assemblies, and the valve train. Compression and suction was confirmed on the number 1, 3, 4, 5, and 6 cylinders. The number 2 intake valve remained partially open during crankshaft rotation, which prevented compression on the number 2 cylinder. The interiors of the cylinders were examined using a lighted borescope and there was no damage to the piston domes, cylinder walls, or valves. Both magnetos and the ignition harness were damaged by fire and could not operate. The upper spark plugs were light brown in color and exhibited wear consistent with normal engine operation. The engine driven fuel pump was fire damaged and did not operate. The fuel servo was fractured across the throttle bore and exhibited fire damage. The inlet fuel screen was free of contaminants. The fuel injector nozzles were clean and free of obstructions. The vacuum pump drive coupling was melted, which prevented a functional test. Disassembly of the vacuum pump revealed that its rotor and vanes were intact. The left propeller remained attached to the crankshaft flange. Both propeller blades were curled aft approximately 90 degrees, and exhibited chordwise scratches and thermal damage. One blade exhibited leading edge gouges and trailing edge S-shape bending. The right engine was resting upright on the ground and remained partially attached to the airframe. The entire engine assembly exhibited thermal damage. The engine crankcase exhibited an offset fracture between the number 1 and 2 cylinder mounting pads, which prevented the rotation of the engine crankshaft. The interiors of the cylinders were examined using a lighted borescope and there was no damage to the piston domes, cylinder walls, or valves. The crankshaft and connecting rods were examined through openings in the bottom of the crankcase and no separations were identified. Both magnetos and the ignition harness were damaged by fire and could not operate. The upper spark plugs were light brown in color and exhibited wear consistent with normal engine operation. The engine driven fuel pump was not recovered. The fuel servo was destroyed by fire. The fuel injector nozzles were clean and free of obstructions. The vacuum pump body was separated from the engine and fragmented. The vacuum pump drive coupling was melted. The right propeller remained attached to the crankshaft flange. One propeller blade was bent forward approximately 90 degrees about 1 foot outboard of the hub. This propeller blade exhibited leading edge gouges, chordwise scratches, and blade twisting. The other propeller blade was bent aft approximately 30 degrees about 2 feet outboard of the hub and exhibited chordwise scratches. Examination of the recovered wreckage revealed no evidence of a pre-impact mechanical malfunction.
MEDICAL AND PATHOLOGICAL INFORMATION
On August 15, 2006, autopsies were performed on the flight instructor and the dual student at the Sault Area Hospital, Sault Ste. Marie, Ontario, Canada, and their cause of death was attributed to traumatic injuries received during the accident. Toxicology samples for the pilots were submitted to the FAA Civil Aeromedical Institute, Oklahoma City, Oklahoma. Toxicology results for both pilots were negative for all tests performed.
ADDITIONAL INFORMATION
According to FAA regulation 91.175(c), Operation below Decision Height or MDA, no pilot may continue below the authorized MDA unless the airplane is continuously in a position from which a descent to a landing on the intended runway can be made at a normal rate of descent using normal maneuvers, the flight visibility is not less than the visibility prescribed for the instrument approach procedure, and the runway environment is distinctly visible and identifiable to the pilot. According to FAA regulation 91.175(e), Missed Approach Procedures, a pilot must immediately execute an appropriate missed approach procedure when an identifiable part of the airport is not distinctly visible to the pilot during a circling maneuver at or above MDA, unless the inability to see an identifiable part of the airport results only from a normal bank of the aircraft during the circling approach. While en route, about 23 minutes before the accident, the pilot reported that he had the current weather at the destination airport. At that time, the reported weather was scattered clouds at 900 feet above ground level (agl), an overcast ceiling at 3,500 feet agl, and a visibility of 3 miles. At the time of the accident, the airport's reported weather was 300 feet agl overcast ceiling and a 1-1/4 mile visibility. The flight was cleared for the VOR-A instrument approach procedure, circle to land runway 27. According to aircraft radar track data, the airplane descended below the approach's authorized minimum descent altitude (MDA) about 2.6 miles northeast of the airport. The airplane leveled off about 175 feet below the MDA until crossing over the intersection of the airport's two runways. The airplane then made a left turn to the east, and paralleled runway 27 about 600 feet south of the runway. The airplane's last radar return was at 185 feet agl and about 0.5 miles east of the runway threshold. The point-of-impact was about 725 feet north of the final radar return. Numerous witnesses reported seeing the airplane traveling eastbound approximately 150 and 200 feet agl, and then perform a left turn back towards the airport before impacting nose first into the terrain. Several of those witnesses reported that the airplane reached a bank angle of approximately 90 degrees during the turn. The airplane's altitude and proximity to the runway prevented an approach to landing using normal flight maneuvers. A majority of the airframe was destroyed during a post-impact ground fire. Examination of the recovered wreckage revealed no evidence of a pre-impact mechanical malfunction. According to FAA regulations," no pilot may continue below the authorized MDA unless the airplane is continuously in a position from which a descent to a landing on the intended runway can be made at a normal rate of descent using normal maneuvers, the flight visibility is not less than the visibility prescribed for the instrument approach procedure, and the runway environment is distinctly visible and identifiable to the pilot." Source: NTSB Aviation Accident Database (Pre-2008 Archive) Retrieved: 2026-02-12
Verbatim from NTSB's published report. Source file
NTSB_2006_CHI06FA232.txt.
Findings + structured fields enriched from FAA avall.mdb.
Full investigation docket on
data.ntsb.gov ↗.
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