# NTSB ANC02FA020: Cessna 208B, N208TF, Barrow, AK, March 6, 2002 - Type: NTSB accident investigation - Classification: Accident · No injuries · Field investigation · Final report - Date: March 6, 2002, 12:03 local (16:03 UTC) - Place: Barrow, AK - Coordinates: 70.616943, -155.001388 - Nearby events: https://openairdocs.org/map.md?lat=70.6169&lon=-155.0014&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 5 uninjured - Status: Completed, report August 26, 2002 - Report: Approved by Office Director - NTSB office: Alaska Regional Office - Parties: Fairbanks FSDO-01 - NTSB case key (mKey): 54309 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC02FA020 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/54309/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=54309 - Page: https://openairdocs.org/ntsb/ANC02FA020 ## Probable cause The pilot's continued flight into adverse weather conditions, and an inadvertent stall. Factors associated with the accident are fog, obscuration, and icing conditions. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - In flight encounter with weather, approach - weather condition - fog (contributing factor) - weather condition - obscuration (contributing factor) - weather condition - icing conditions (contributing factor) - flight into known adverse weather - continued, pilot in command (cause) - Loss of control - in flight, approach - stall/mush - inadvertent, pilot in command (cause) - In flight collision with terrain/water, descent - uncontrolled - terrain condition - snow covered ## Analysis The air taxi pilot was flying four passengers and cargo to a remote camp and airstrip surrounded by principally flat, snow-covered tundra. He had difficulty locating the airstrip due to ice fog and reduced visibility, and initially flew over the top of the runway. A passenger saw the airstrip, and about the same time, the camp operator radioed the pilot that the airplane had just passed the camp. The pilot made a descent and an approach to the airstrip, but the airplane stalled and collided with terrain about 1/4 mile short of the runway. The camp operator noted that at the time of the accident there was ice fog in the area, and a portion of the runway was not visible due to the fog. He estimated the horizontal visibility to be about 3/4 of a mile. Postaccident inspection of the airplane disclosed approximately 1/2 inch of ice on the airplane's left lift strut and main landing gear leg. The pilot said after the accident that either a cabin door or cargo pod door may have opened during the approach. Postaccident inspection, and interviews with passengers, disclosed no evidence of an in-flight cargo or cabin door opening, and crush lines on the cargo pod door are consistent with the door being closed at impact. ## Factual narrative HISTORY OF FLIGHT On March 6, 2002, about 1203 Alaska standard time, a wheel-equipped Cessna 208B airplane, N208TF, sustained substantial damage during approach to landing at a remote airstrip, known as Puviak, approximately 52 nautical miles southeast of Barrow, Alaska. The airplane was being operated as a visual flight rules (VFR) on demand charter flight under Title 14, CFR part 135, when the accident occurred. The airplane was operated by Tatonduk Flying Service of Fairbanks, Alaska. The airline transport pilot and the four passengers were not injured. The company's VFR flight following procedures were in effect. The flight originated at the Deadhorse Airport, Deadhorse, Alaska, about 1110, and was bound for Puviak. During a telephone conversation with the National Transportation Safety Board (NTSB) investigator-in-charge (IIC) on March 6, the company site manager at Puviak said he, and other personnel on the ground, saw and heard the airplane pass overhead, and radioed the airplane. He said the prepared runway was a compacted and marked snowfield, about 4,500 feet long. He said because of the fog, he could only see about three-quarters of the length of the runway. The airplane turned toward the runway, but crashed before reaching it. During a telephone conversation with the IIC on March 9, the right front seat passenger said he was seated in the right front seat, and that he was wearing a headset. He said he was talking to the pilot on the intercom, and heard the radio call from the ground, advising them they had just passed over the airstrip. He said he never saw the airstrip, but the passenger seated behind the pilot did. He said during the flight from Deadhorse their cruising altitude was 8,000 feet, and the visibility was good, but as they approached the airstrip they "descended into the fog." He said from 500 feet they could see the ground. The passenger said once they started the left turn toward the airstrip the airplane started to shake, and porpoise. He said the pilot applied full power, and leveled the wings, but the airplane impacted the ground seconds later. He said once on the ground, outside the airplane, it was not raining or snowing, but it was foggy. During a telephone conversation with the IIC on March 11, the pilot said that he passed over Puviak without seeing the airstrip. He said a passenger on the left side of the airplane spotted the airstrip, and then he received the radio call from the ground stating they just passed overhead. He said while he was making a standard rate left turn toward the airstrip, the airplane started to vibrate, shake, fishtail from side-to-side, and descend. He applied full power and leveled the wings. The airplane impacted on flat, snow-covered ground, about one-quarter mile from the airstrip. The pilot said he believed the number 4 cargo pod door came open in-flight. The number 4 cargo pod door is located farthest aft on the left side of the belly mounted cargo pod. The number 4 door cannot be seen from the pilot's position in-flight, and there is no warning indication if the door is open. He said he thought this happened because the number 4 door separated from the cargo pod at the point of impact. The pilot said that there were bands of fog in the area, but basic VFR conditions prevailed at the accident site. He further stated there were no signs of airframe icing on the airplane. During a telephone conference call with the IIC on March 11, Federal Aviation Administration (FAA) airworthiness inspectors, who visited the accident site on March 9, stated that they saw evidence of in-flight icing on the airplane. They provided the IIC with photographs showing the buildup of ice on the leading edge of the left wing lift-strut. The ice builds from the leading edge rearward on both top and bottom of the lift-strut. PERSONAL INFORMATION The pilot held a commercial and airline transport certificate with FAA ratings for single-engine land, single-engine sea, multi-engine land, and instrument airplane. The pilot was issued an FAA First Class Medical certificate on February 25, 2002. According to information received from the pilot, he has accumulated 22,000 total flying hours, 2,000 of which were in the make and model of the accident airplane, and he has accumulated 1,000 hours of instrument flying time. AIRCRAFT INFORMATION The airplane was equipped with an icing equipment package certified for flight into known icing conditions. The package included pneumatic deicing boots on the wings, wing struts, horizontal stabilizer, and vertical stabilizer. The package also included electrically heated propeller blade anti-ice boots, a detachable electrical windshield anti-ice panel, electric pitot/static heat system, a standby electrical system, and inertia separator. The airplane was not equipped with any ice protection equipment on its landing gear struts or the cargo pod. According to the load manifest provided by the operator, the airplane's takeoff weight was estimated to be 8658 pounds. According to the Cessna 208B INFORMATION MANUAL, the maximum allowable takeoff weight into known icing is 8550 pounds. METEOROLOGICAL INFORMATION The unofficial weather at the accident site, as reported by the site manager at the time of the accident, was sky partially to totally obscured by fog. The horizontal visibility at ground level was estimated to be 3/4 of a mile or less, and the temperature was 11 degrees F. The closest official weather reporting stations to Puviak are Deadhorse and Barrow, Alaska. At 1153, Barrow, which is about 52 nautical miles northwest of the accident site, reported 2 1/2 miles visibility which decreased to 3/4 of a mile within the following 30 minutes. Barrow was also reporting a ceiling to of 100 feet variable to 500 feet. The temperature and dewpoint were both 12 degrees F. Deadhorse, which is about 130 nautical miles due east of the accident site, at 1153, reported 7 miles visibility with an overcast at 2,100 feet. Deadhorse's weather reported at 1053, was, 1 1/4 mile visibility in light snow with a ceiling at 600 to 800 feet. The temperature and dewpoint were 10 and 9 degrees F, respectively. An AIRMET was issued for the northern half of the state of Alaska, and was valid through 1200. The AIRMET forecast severe icing above the freezing level, which was at the surface, low-level wind shear, and IFR conditions. WRECKAGE AND IMPACT INFORMATION The airplane impacted on relatively flat, snow-covered ground, in a level, left wing low attitude. The cargo pod was crushed. All three landing gear were damaged, along with the propeller and engine mounts. There was structural damage to the landing gear attachments, firewall, and belly of the airplane. The number 4 cargo pod door, when placed in the closed position, exhibited crush marks matching the marks on the door frame and cargo pod. See attached photographs. No pieces or parts of the wreckage were taken or retained by the Safety Board. ADDITIONAL INFORMATION In a telephone conversation with the director of operations for the operator, which preceded the IIC's conversation with the pilot, the director of operations said the pilot had originally told him the upper half of the clamshell style cargo door came open in flight. This door is located on the aft left section of the fuselage passenger/cargo compartment. The door is equipped with an electrical switch which illuminates the red DOOR WARNING light on the pilot's annunciator panel when the door is not closed and latched properly. During interviews, and in written statements, none of the passengers in the passenger/cargo compartment said they saw the clamshell style cargo door open in-flight. The pilot said the red DOOR WARNING light did not illuminate during the flight. A subsequent inspection of the door, and the latching mechanism, showed that the mechanism was not damaged a ## Aircraft - Registration: [N208TF](https://openairdocs.org/aircraft/N208TF), registered now, S/N 208B0592, built 1997 (OpenAirDocs) - Reported make and model: Cessna 208B - Registry model: [Cessna 208B](https://openairdocs.org/model/cessna-208b) (registry code 2073701) (OpenAirDocs) - Registry engine: [Pratt & Whitney PT6A series](https://openairdocs.org/engine/pratt-whitney-pt6a-series) (registry code 52032, turbo-prop) (OpenAirDocs) - Category: Airplane - Serial number: 208B0529 - Airframe hours: 4676 - Engines: P&W PT6A-114A 675 horsepower turbo prop - Damage: Substantial damage - Flight: Part 135 - Operator: Tatonduk Outfitters Ltd, doing business as Tatonduk Flying Service - Registered owner: C&R Leasing, LLC - Airworthiness certificate: Standard, Normal - Last inspection: AAIP, February 12, 2002, 58.3 hours before - Departed: PASC, Deadhorse, AK - Destination: Barrow, AK - Flight plan: Company VFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 50; injuries: none; airline transport, commercial; airplane ratings: multi-engine land, single-engine sea, single-engine land; instrument ratings: airplane; medical: class 1, valid medical--w/ waivers/lim; last flight review December 22, 2001; seat: left; flight hours: 22,000 total, 2,000 in this make and model, 165 in the last 90 days, 49 in the last 30 days, 4 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 1.5 statute miles - Temperature: 10 °F ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 20020306003309A](https://openairdocs.org/incident/20020306003309A), Mar 6, 2002: Cessna 208B, Barrow, AK, No damage. (-23) Pilot (200 lbs) picked up 4 adult males (760 lbs) with baggage (304 lbs), and approximately 1400 lbs. Of freight, with an estimated 1400 to 1450 lbs fuel… ## Other investigations on N208TF (1) From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. - [NTSB CEN11CA309](https://openairdocs.org/ntsb/CEN11CA309), Apr 27, 2011: Cessna 208B (N208TF), El Paso, TX, substantial damage. Probable cause: The pilot's loss of control as result of the gusting wind. ## Docket (9 files) The files NTSB released with the investigation on July 29, 2002, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=54309. 1.5 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 512 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40392697&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Photo 1: Taken shortly after the accident, note the sky condition. The number 4 cargo door opening can be seen aft of the left main landing gear assembly. (item 2, .PDF, 136 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40163560&FileExtension=.PDF&FileName=Photo%201%3A%20Taken%20shortly%20after%20the%20accident,%20note%20the%20sky%20condition.%0D%0AThe%20number%204%20cargo%20door%20opening%20can%20be%20seen%20aft%20of%20the%20left%20main%20landing%20gear%20assembly.-Master.PDF - Photo 2: Taken the day after the accident at the accident site. Note the ice on the leading edge of the left lift strut. (item 3, .PDF, 70 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40163796&FileExtension=.PDF&FileName=Photo%202%3A%20Taken%20the%20day%20after%20the%20accident%20at%20the%20accident%20site.%0D%0ANote%20the%20ice%20on%20the%20leading%20edge%20of%20the%20left%20lift%20strut.-Master.PDF - Photo 3: Taken the day after the accident. Note ice on the lower portion of the left lift strut and left main landing gear leg. (item 4, .PDF, 56 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40163797&FileExtension=.PDF&FileName=Photo%203%3A%20Taken%20the%20day%20after%20the%20accident.%0D%0ANote%20ice%20on%20the%20lower%20portion%20of%20the%20left%20lift%20strut%20and%20left%20main%20landing%20gear%20leg.-Master.PDF - Photo 4: Taken the day after the accident. Note ice on the leading edge of the left main landing gear. (item 5, .PDF, 60 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40163798&FileExtension=.PDF&FileName=Photo%204%3A%20Taken%20the%20day%20after%20the%20accident.%0D%0ANote%20ice%20on%20the%20leading%20edge%20of%20the%20left%20main%20landing%20gear.-Master.PDF - Photo 5: Taken the day after the accident. The point of impact to final resting place. (item 6, .PDF, 83 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40163799&FileExtension=.PDF&FileName=Photo%205%3A%20Taken%20the%20day%20after%20the%20accident.%20The%20point%20of%20impact%20to%20final%20resting%20place.-Master.PDF - Photo 6: Taken the day after the accident. Note crushed aft left protion of the cargo pod, missing the number 4 door. (item 7, .PDF, 65 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40163800&FileExtension=.PDF&FileName=Photo%206%3A%20Taken%20the%20day%20after%20the%20accident.%20Note%20crushed%20aft%20left%20protion%20of%20the%20cargo%20pod,%20missing%20the%20number%204%20door.-Master.PDF - Photo 7: Taken in a hanger at Anchorage, Alaska. The number 4 cargo door in its frame in the closed position. Note the crush lines. (item 8, .PDF, 291 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40163801&FileExtension=.PDF&FileName=Photo%207%3A%20Taken%20in%20a%20hanger%20at%20Anchorage,%20Alaska.%20The%20number%204%20cargo%20door%20in%20its%20frame%20in%20the%20closed%20position.%20Note%20the%20crush%20lines.-Master.PDF - Photo 8: Taken in a hanger at Anchorage, Alaska. The number 4 cargo pod door is compared with the crushed door frame. (item 9, .PDF, 233 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40163802&FileExtension=.PDF&FileName=Photo%208%3A%20Taken%20in%20a%20hanger%20at%20Anchorage,%20Alaska.%20The%20number%204%20cargo%20pod%20door%20is%20compared%20with%20the%20crushed%20door%20frame.-Master.PDF From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.