CEN18FA160

NTSB accident investigation · Belair Raven · Sault Ste Marie, MI · May 5, 2018

Accident · FatalField investigationFinal report
Date
May 5, 2018, 10:02 local (14:02 UTC)
Place
Sault Ste Marie, MI
Injuries
2 fatal
Damage
Substantial damage
Phase of flight
Takeoff
Aircraft
C-FNKZBelair Raven
Defining event
Takeoff: Loss of control in flight
Weather
Visual (VMC) · Day
Status
Completed · report June 25, 2019
Report
Approved by Office Director
NTSB office
Central Region
Parties
Flight Standards District Office
Case key
97176

From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.

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Probable cause

The pilot's failure to maintain adequate airspeed during takeoff in gusty crosswind conditions, which resulted in the airplane exceeding its critical angle of attack and an aerodynamic stall.

Findings · 4

NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings. Under each, the cases with the same finding.

Use of equip/info: aircraft controlPersonnel issues › Task performance · PilotAll aircraft: 9,295 casesProbable cause
Performance/control parameters: airspeedAircraft › Aircraft oper/perf/capability · Not attained/maintainedAll aircraft: 1,681 casesProbable cause
Performance/control parameters: angle of attackAircraft › Aircraft oper/perf/capability · Capability exceededAll aircraft: 990 casesProbable cause
Wind: gustsEnvironmental issues › Conditions/weather/phenomena · Effect on equipmentAll aircraft: 1,199 cases

Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident. Under each, the cases with the same event anywhere in their sequence.

Analysis

The private pilot and pilot-rated passenger were departing on a local flight in the experimental, amateur-built airplane in gusting crosswind conditions. Witnesses saw the airplane take off and enter a nose-high attitude. About 100 ft above ground level, the airplane began turning right and transitioned to a nose-low spin until ground impact. Examination of the airframe and engine revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation. The airplane was not equipped with any stall warning devices. The witness reports and damage to the airplane were consistent with the pilot failing to maintain sufficient airspeed during a steep takeoff climb, which resulted in the airplane exceeding its critical angle of attack and a subsequent aerodynamic stall. A flight instructor at the airport reported that, when departing the accident runway with westerly winds present, he would often notice turbulence and swirling air. He attributed this effect to the tall trees located about 100 yards west of the runway. Although autopsies revealed that both pilots were at risk for a sudden cardiac event, the circumstances of the accident are consistent with a loss of control rather than a sudden incapacitation, and it is unlikely that either pilot's cardiac condition contributed to the accident.

Factual narrative

According to the flight instructor who witnessed the accident, during departures from runway 32 with westerly winds present, he would often notice turbulence and swirling air. He attributed this effect to the tall trees located about 100 yards west of the runway. The high-wing, tailwheel-equipped airplane was completed by the pilot in 2012 and was issued a Canadian Special Certificate of Airworthiness. The airplane was equipped with a Honda 3.5-liter engine and a Performance three-blade, fixed pitch wooden propeller. The airplane was not equipped with any stall warning devices. On the day of the accident, the airplane was lightly loaded with cargo. ANJ was a public, non-towered airport owned by the City of Sault Saint Marie. The airport had one runway and surveyed elevation of 716 ft above mean sea level. Runway 14/32 was a 5,234 ft by 100 ft runway with an asphalt surface. On May 5, 2018, at 1002 eastern daylight time, an experimental, amateur-built Belair Raven airplane, Canadian registration C-FNKZ, impacted terrain during the initial climb after takeoff from Sault Ste. Marie Municipal Airport (ANJ), Sault Ste. Marie, Michigan. The private pilot and pilot-rated passenger were fatally injured, and the airplane was substantially damaged. The airplane was owned by the pilot who was operating it as a Title 14 Code of Federal Regulations Part 91 personal flight. Day, visual meteorological conditions prevailed for the local flight, which departed without a flight plan. According to witnesses, the airplane taxied to runway 32 and departed in a nose-high attitude. A flight instructor compared the climb to an aggressive short-field takeoff or a banner pilot's climb after picking up a banner. Witnesses noticed that, after reaching about 100 ft above ground level, the airplane turned right and transitioned to a steep nose-down spin until ground impact. The flight instructor stated that the engine noise sounded normal throughout the takeoff until ground impact. The Chippewa County Medical Examiner, Sault Ste. Marie, Michigan, conducted autopsies of the pilot and passenger and determined that the cause of their deaths was due to blunt force injuries. The pilot's autopsy revealed left ventricular hypertrophy, a thickening of the wall of the left ventricle. The coronary arteries were free from atherosclerosis. An area of scar in the subepicardial area of the anterior wall of the left ventricle as well as some fibrosis in the lateral and posterior walls were identified with microscopy. The remainder of the cardiac examination was unremarkable. The pilot's wife stated that the pilot had experienced chest pains about 3 years before the accident, but she was not aware of any recent significant health issues. The passenger's autopsy revealed evidence of bilateral corneal transplants and emphysema. An area of 70-80% stenosis was identified in the left anterior descending coronary artery and there was some evidence of perivascular fibrosis on the microscopicexamination in the anterior and lateral walls, as well as the left side of the septum. The passenger's son stated that, during the 2 years before the accident, his father would get tired more easily during walks and while climbing stairs. The Federal Aviation Administration Bioaeronautical Sciences Research Laboratory, Oklahoma City, Oklahoma, conducted toxicological testing on specimens from the pilot and passenger. The results were negative for all tests conducted. At 0955, the automated weather observation station (AWOS) at ANJ reported wind from 270° at 11 knots with gusts to 15 knots, 10 miles visibility, clear skies, temperature 12°C, dew point 3°C, and an altimeter setting of 29.93 inches of mercury. The AWOS was located about 1/4 mile east of the runway. The pilot, age 67, held a Canadian private pilot certificate with an airplane single-engine land rating. On February 8, 2018, the pilot was issued a Canadian Category 3 medical certificate with a requirement for glasses to be worn and a restriction of day visual only flight due to color vision deficiencies. The pilot had accumulated 505 total hours of flight experience, with 61 hours in the accident airplane. Flight reviews were not recorded in the pilot's logbook. The pilot-rated passenger, age 75, held a Canadian private pilot certificate with an airplane single-engine land rating. On January 24, 2018, the passenger was issued a Canadian Category 1 medical certificate with a requirement for glasses to be worn. The passenger frequently flew with the pilot in the accident airplane. Examination at the accident site revealed that the airplane impacted terrain and came to rest in a near-vertical, nose-down attitude on a heading about 201° about 180 ft east of runway 32. Both wings were crushed aft and remained attached to the fuselage. The fixed main landing gear assemblies were attached to the fuselage and the flight control surfaces remained attached to their respective airframe surfaces; elevator control, elevator trim, and rudder control continuity was established to the cockpit area. Aileron control continuity was established from both ailerons to the cockpit. The left aileron cable, which was slack, was disengaged from its respective bellcrank. All three multilaminate wood propeller blades were fractured near the hub. The propeller remained attached to the engine and the spinner was crushed aft. The engine was rotated by hand from the front crankshaft. Thumb suction and compression was observed at all cylinders with normal valve train and crankshaft continuity. Spark plug electrodes exhibited normal wear signatures. Witness marks on the seat rails indicated that both pilot and passenger seats were in a normal position during ground impact. Examination of the airframe and engine revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation.

Aircraft

Registration
C-FNKZ
Reported as
Belair Raven
Category
Airplane, amateur-built
Serial number
12351
Built
2012
Airframe hours
61
Engine
Honda 3.5 Litre, 245 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Airworthiness certificate
Special, Experimental (Special)
Departed
ANJ · Sault Ste Marie, MI
Destination
ANJ · Sault Ste Marie, MI
Airport
ANJ · Sault Ste Marie Muni/Sanderson, runway 32, 5,234 × 100 ft, asphalt
Equipment
Electronic primary flight display

Flight crew · 2

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
67
Injuries
Fatal
Certificate
Private
Airplane ratings
Single-engine land
Medical
Class 3, With waivers/limitations
Seat
Left
Restraint
4-point
Toxicology
Performed
Flight hours
505 total · 61 in this make and model · 455 as pilot in command · 8 in the last 90 days · 2 in the last 30 days · 0 in the last 24 hours
Role
Pilot-rated passenger
Age
75
Injuries
Fatal
Certificate
Private
Airplane ratings
Single-engine land
Medical
Class 1, With waivers/limitations
Seat
Right
Restraint
4-point
Toxicology
Performed

Weather

Conditions
Visual (VMC) · Day
Wind
270° at 11 knots, gusting 15
Visibility
10 statute miles
Lowest ceiling
None
Temperature
54 °F, dew point 37 °F
Altimeter
29.93 inHg
Observed at
KANJ

Docket · 6

The files NTSB released with the investigation on May 21, 2019, on NTSB’s docket system: statements, records, photos and specialists’ reports. 1.1 MB in all.