ASN logo
Accident description
Last updated: 21 August 2017
Status:Final
Date:Thursday 20 November 2014
Time:07:21
Type:Silhouette image of generic C208 model; specific model in this crash may look slightly different
Cessna 208B Grand Caravan
Operator:Air Tindi
Registration: C-FKAY
C/n / msn: 208B-0470
First flight: 1995
Total airframe hrs:25637
Engines: 1 Pratt & Whitney Canada PT6A-114A
Crew:Fatalities: 0 / Occupants: 1
Passengers:Fatalities: 0 / Occupants: 5
Total:Fatalities: 0 / Occupants: 6
Airplane damage: Substantial
Location:40 km (25 mls) W of Yellowknife, NT (   Canada)
Phase: En route (ENR)
Nature:Domestic Scheduled Passenger
Departure airport:Yellowknife Airport, NT (YZF/CYZF), Canada
Destination airport:Fort Simpson Airport, NT (YFS/CYFS), Canada
Flightnumber:8T223
Narrative:
A Cessna 208B Grand Caravan, operated by Air Tindi, sustained substantial damaged in a forced landing on the frozen surface of Great Slave Lake, Canada.
Flight 223 from Yellowknife Airport (CYZF), Northwest Territories, to Fort Simpson Airport (CYFS), Northwest Territories had originally been scheduled for 19 November 2014 at 18:00 local time but was cancelled because of freezing drizzle reported in Fort Simpson. The flight was rescheduled for 20 November 2014 at 06:00. Its early-morning departure was intended to enable the regularly scheduled return flight to depart Fort Simpson at 08:00 with minimal delay.
The pilot reported for duty at 05:00 to prepare for the flight. A pre-flight inspection was performed, wing covers were removed, and no contamination was observed on the wings. The pilot filed an IFR flight plan and checked for enroute icing condition reports. There were no reported airmen’s meteorological information (AIRMET) and pilot weather report (PIREP) for the flight-planned route. No other weather information was requested or offered.
The airplane departed Yellowknife at approximately 06:42, with an IFR clearance to 8000 feet above sea level. During the climb, the aircraft encountered cloud layers; at approximately 06:51, flying through 6000 feet asl, it encountered icing conditions. The aircraft continued to climb and levelled off at 8000 feet asl, where cruise power was set. The airspeed did not accelerate beyond 120 knots indicated airspeed (KIAS), and the flight began to descend with cruise power set. At 06:59, the pilot contacted the Edmonton, Alberta, Area Control Centre (ACC) and requested a lower altitude, as he was unable to maintain 120 KIAS. Edmonton ACC cleared the flight to 6000 feet asl direct to Fort Simpson. During the controlled descent, airspeed continued to decline below 120 KIAS, even with the application of maximum continuous power. At 07:06, a request was made to Edmonton ACC to return to CYZF because of severe icing. Flight 223 was ultimately cleared to Yellowknife at 3000 feet asl.
The pilot experienced periods of elevator buffeting and uncommanded forward pitch movements during the turn. He continued the descent in order to maintain 110 KIAS. Flap position remained fully up, as the pilot was concerned that movement would further affect tailplane effectiveness.
At 07:17, the pilot advised Yellowknife Tower that the aircraft was in severe icing conditions and unable to maintain altitude. It was cleared to 2100 feet asl (minimum vectoring altitude). At 07:19, the pilot experienced a significant uncommanded pitch forward and advised ATC that they were unable to maintain 2100 feet asl; a Mayday was declared.
At 07:20, when the aircraft was 300 feet above ground level, the pilot experienced a series of wing drops and an associated rate of descent of 1200 feet per minute at 100 to 110 KIAS. In response, the power lever was pushed fully forward, exceeding the maximum continuous rating of 1865 foot-pounds of torque. No flap selections were made.
While still in darkness, the aircraft contacted the frozen surface of Great Slave Lake at 07:21, and continued moving for 2300 feet before it struck a rock outcropping with the nose and left main landing gear. The aircraft came to rest approximately 600 feet from the outcropping and 2900 feet from the initial touchdown point. There were no injuries to the occupants, but the aircraft was severely damaged. There was no post-impact fire.
Passenger evacuation was ordered once the pilot had assessed the situation. Passengers attempted to open the main cabin door but were unable to do so. After several failed attempts to evacuate, the passengers succeeded in exiting via the left cockpit door with the aid of cockpit lighting.

Probable Cause:

Findings as to causes and contributing factors:

1. Not using all enroute information led the pilot to underestimate the severity and duration of the icing conditions that would be encountered.
2. Inadequate awareness of aircraft limitations in icing conditions and incomplete weight-and-balance calculations led to the aircraft being dispatched in an overweight state for the forecast icing conditions. The aircraft centre of gravity was not within limits, and this led to a condition that increased stall speed and reduced aircraft climb performance.
3. The pilot's expectation that the flight was being undertaken at altitudes where it should have been possible to avoid icing or to move quickly to an altitude without icing conditions led to his decision to continue operation of the aircraft in icing conditions that exceeded the aircraft's performance capabilities.
4. The severity of the icing conditions encountered and the duration of the exposure resulted in reductions in aerodynamic performance, making it impossible to prevent descent of the aircraft.
5. The inability to arrest descent of the aircraft resulted in the forced landing on the surface of Great Slave Lake and the collision with terrain.
6. The Type C pilot self-dispatch system employed by Air Tindi did not have quality assurance oversight or adequate support systems. This contributed to the aircraft being dispatched in conditions not suitable for safe flight.

Accident investigation:
cover
Investigating agency: TSB Canada
Status: Investigation completed
Duration: 1 year and 4 months
Accident number: A14W0181
Download report: Final report

Classification:
Icing
Forced landing outside airport

Sources:
» CBC
» CADORS 2014C4484

METAR Weather report:
13:00 UTC / 06:00 local time:
METAR CYZF 201300Z 10011KT 15SM -SN OVC012 M10/M12 A2967 RMK SC8 SLP068=

14:00 UTC / 07:00 local time:
METAR CYZF 201400Z 10012KT 12SM -SN OVC012 M10/M12 A2965 RMK SC8 SLP060=

14:24 UTC / 07:24 local time:
SPECI CYZF 201424Z 09011KT 6SM -FZDZ -SN FEW008 OVC012 M10/M12 A2964 RMK SF1ST8 SF TR SLP058=


Follow-up / safety actions
Following the occurrence, Air Tindi temporarily suspended Cessna Caravan operations, conducted a safety management system investigation and undertook a number of safety actions. These included enhanced oversight of aircraft dispatch procedures, more thorough weather monitoring, improved training for operations in icing conditions, and updating the company's emergency response plan.

Photos

photo of Cessna 208B Grand Caravan C-FKAY
photo of Cessna 208B Grand Caravan C-FKAY
Aerial view, looking south, of the accident site
photo of Cessna 208B Grand Caravan C-FKAY
Ice accretion from the flight on the radome of the right wing and ice ridges aft of the de-ice boots on the leading edge of the wing
photo of Cessna 208B Grand Caravan C-FKAY
flight path
photo of Cessna 208B Grand Caravan C-FKAY
Altitude versus airspeed data
Add your photo of this accident or aircraft
 

Map
This map shows the airport of departure and the intended destination of the flight. The line between the airports does not display the exact flight path.
Distance from Yellowknife Airport, NT to Fort Simpson Airport, NT as the crow flies is 359 km (224 miles).

This information is not presented as the Flight Safety Foundation or the Aviation Safety Network’s opinion as to the cause of the accident. It is preliminary and is based on the facts as they are known at this time.
languages: languages

Share