ANC13LA100

NTSB accident investigation · Cessna U206F · Kotzebue, AK · September 13, 2013

Accident · Serious injuriesLimited investigationFinal report
Date
September 13, 2013, 13:15 local (21:15 UTC)
Place
Kotzebue, AK
Injuries
2 serious
Damage
Substantial damage
Phase of flight
Enroute
Aircraft
N8316QCessna U206F
Defining event
Enroute-cruise: VFR encounter with IMC
Weather
Visual (VMC) · Day
Status
Completed · report August 14, 2014
Report
Approved by Office Director
NTSB office
Alaska Regional Office
Parties
Cessna Aircraft Company, FAA - Fairbanks Flight Standards District Office
Case key
88042

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 improper decision to continue visual flight rules flight into instrument meteorological conditions, which resulted in controlled flight into terrain.

Findings · 2

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.

Performance/control parameters: altitudeAircraft › Aircraft oper/perf/capability · Not attained/maintainedCessna U206F: 3 casesAll aircraft: 1,310 casesProbable cause

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

Before departing from a remote hunting site on a short cross-country flight, the accident pilot obtained a pilot report from another pilot who had just flown the route. The pilot report indicated 25 miles visibility, clouds at 1,400 feet, and a cloud ceiling at 1,800 feet. The airplane departed uneventfully, and, about 15 minutes into the 30-minute flight, the airplane approached the last ridge before the destination airport. The top of the ridge was about 1,950 feet mean sea level. The pilot stated that the destination airport peninsula was visible in the distance with an estimated 500 feet of clearance between the top of the ridge and the base of the cloud ceiling. He added that, as the airplane neared the ridge, the airplane encountered a severe downdraft and an abrupt entry into instrument meteorological conditions and then subsequently collided with the ridge about 30 to 50 feet below the ridgeline. However, review of handheld GPS data revealed that the airplane was in a constant climb during the minutes leading up to the collision with the ridge except for a 6-foot descent just before the collision. Additionally, the nearest reporting weather station reported a cloud ceiling about 50 feet below the ridgeline. The pilot noted no preimpact mechanical malfunctions with the airplane that would have precluded normal operation. Thus, it is likely that the pilot was flying the airplane low to stay below the clouds and then began to climb the airplane to clear the ridge when he entered instrument meteorological conditions as the airplane approached the ridge.

Factual narrative

On September 13, 2013, about 1315 Alaska daylight time, a Cessna U206F airplane, N8316Q, operated by a private individual, was substantially damaged when it collided with mountainous and hilly terrain about 25 miles northeast of Kotzebue, Alaska. The commercial pilot and passenger were seriously injured. The personal flight was conducted under the provisions of 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed for the planned flight to Ralph Wien Memorial Airport, Kotzebue, Alaska. No flight plan was filed for the flight that departed from a remote hunting camp near Kiana, Alaska, about 1300. The pilot stated that the purpose of the accident flight was to get supplies at Kotzebue and return to the hunting camp. Prior to departure, he obtained a pilot report from another pilot that had just flown the route. The pilot report included visibility 25 miles, clouds at 1,400 feet, and a ceiling at 1,800 feet. The accident airplane departed uneventfully and was in cruise flight as it approached the last ridge before Kotzebue. The pilot further stated that the Kotzebue peninsula was visible in the distance with an estimated 500 feet of clearance, between the top of the ridge and the base of the cloud layer. The pilot added that as the airplane neared the ridge, a severe downdraft was encountered along with abrupt entry into instrument meteorological conditions. He stabilized the airplane using cockpit instrumentation; however, the airplane collided with the ridge about 30 to 50 feet below the ridgeline. The pilot also noted that there were no preimpact mechanical malfunctions with the airplane. A handheld GPS was recovered from the airplane and forwarded to the NTSB Vehicle Recorders Laboratory, Washington, DC, for data download. Review of the downloaded data revealed that during the last 6 minutes of flight, the airplane climbed from a GPS altitude of 709 feet to a GPS altitude of 1,955 feet. During the last 1 minute of flight, as the airplane approached the ridge, it climbed from a GPS altitude of 1,562 feet, to a GPS altitude of 1,955 feet. One second later, the airplane descended 6 feet to a GPS altitude of 1,949 feet, followed by a 10-foot descent to 1,939 feet 8 seconds after; however, the groundspeed between those two records decayed from 53 knots to 12 knots, consistent with collision occurring during that time. After learning about reports of a weak emergency locator transmitter signal north of Kotzebue, search and rescue personnel aboard an Army National Guard UH-60L helicopter were dispatched from Nome, Alaska. The two seriously injured occupants remained at the accident site, while pinned in the wreckage, for approximately 28 hours before rescue personnel could reach the accident site. The closest weather reporting facility was at Kotzebue, about 25 miles southwest of the accident site. At 1253, a weather observation was reporting, in part: Wind from 230 degrees at 17 knots; visibility 9 miles in light rain,broken ceiling at 1,900 feet, overcast ceiling at 2,500 feet; temperature 6 degrees C; dew point 3 degrees C; altimeter 29.81 inches Hg. At 1353, a weather observation was reporting, in part: Overcast ceiling at 1,700 feet.

Aircraft

Registration
N8316Q
Reported as
Cessna U206F
Category
Airplane
Serial number
U20603177
Built
1976
Airframe hours
11,165
Engine
Continental IO-520, 300 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Airworthiness certificate
Standard, Normal
Last inspection
Annual · May 22, 2013 · 15 hours before
Departed
Kiana, AK
Destination
Kotzebue, AK
Equipment
Stall warning system, Handheld GPS

Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

Flight crew

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
61
Injuries
Serious
Certificates
Flight instructor, Commercial
Airplane ratings
Multi-engine land, Single-engine sea, Single-engine land
Instrument ratings
Airplane
Medical
Class 2, Without waivers/limitations
Last flight review
June 24, 2013
Seat
Left
Restraint
3-point
Flight hours
9,275 total · 27 in this make and model · 9,137 as pilot in command · 85 in the last 90 days · 35 in the last 30 days · 2 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
230° at 17 knots
Visibility
9 statute miles
Lowest ceiling
1,900 ft broken
Temperature
43 °F, dew point 37 °F
Altimeter
29.80 inHg
Turbulence
Severe
Observed at
OTZ, 25 nm away

Docket · 11

The files NTSB released with the investigation on March 12, 2014, on NTSB’s docket system: statements, records, photos and specialists’ reports. 2.7 MB in all.

Other investigations on N8316Q · 1

Matched to the same aircraft by N-number and date.