NTSB Identification: ANC16FA017
Nonscheduled 14 CFR Part 135: Air Taxi & Commuter
Accident occurred Friday, April 08, 2016 in Angoon, AK
Probable Cause Approval Date: 05/23/2017
Aircraft: CESSNA 206, registration: N50159
Injuries: 3 Fatal, 1 Serious.
NTSB investigators either traveled in support of this investigation or conducted a significant amount of investigative work without any travel, and used data obtained from various sources to prepare this aircraft accident report.
The commercial pilot was conducting a commercial on-demand flight between two villages over open water in an amphibious float-equipped airplane before navigating through mountainous terrain. As the airplane approached the usual route company pilots took through the mountains, the accident pilot relayed to the operator's director of operations via airborne communications that he was unable to make it through the pass due to low clouds and reduced visibility and that he was going to try an alternate route over lower terrain. After the director of operations determined that the airplane did not arrive at its destination, search and rescue efforts ensued. The airplane was subsequently found in an area of rising steep mountainous, snow-covered terrain at an elevation of about 2,240 ft mean sea level in a near-vertical attitude.
A postaccident examination of the airframe and engine revealed no mechanical malfunctions or anomalies that would have precluded normal operation. GPS data for the accident flight showed the airplane making a total of five 360° turns in various locations in cloud-obscured, mountainous terrain while attempting to make it to the destination; the last turn was made shortly before impact. Based on the conversation the pilot had with the director of operations and the location of the wreckage, it is likely that the pilot thought he had taken a path over lower terrain but that he actually flew into a different valley which had higher-than-anticipated terrain, and then executed a 360° turn to gain altitude before continuing the flight. However, the airplane did not gain sufficient altitude to clear terrain, and it is likely that the pilot attempted another climb, which reduced the airspeed and led to the exceedance of the airplane's critical angle of attack. The disposition of the airplane at the accident site was consistent with an aerodynamic stall and a right spin.
The National Transportation Safety Board determines the probable cause(s) of this accident as follows:
The pilot's inadvertent turn toward terrain that was higher-than-expected while trying to avoid poor visibility conditions and his subsequent attempt to clear terrain, which reduced the airspeed and led to the exceedance of the airplane's critical angle of attack and an aerodynamic stall and spin.
David Robert Galla
Gregory Gene Scheff
Thomas Siekawitch
The National Transportation Safety Board traveled to the scene of this accident.
Additional Participating Entities:
Federal Aviation Administration / Flight Standards District Office; Juneau, Alaska
Textron Aviation; Wichita, Kansas
Continental Motors; Mobile, Alabama
Hartzell Propellers; Piqua, Ohio
Investigation Docket - National Transportation Safety Board: https://dms.ntsb.gov/pubdms
Aviation Accident Factual Report - National Transportation Safety Board: https://app.ntsb.gov/pdf
NTSB Identification: ANC16FA017
Nonscheduled 14 CFR Part 135: Air Taxi & Commuter
Accident occurred Friday, April 08, 2016 in Angoon, AK
Aircraft: CESSNA 206, registration: N50159
Injuries: 3 Fatal, 1 Serious.
NTSB investigators either traveled in support of this investigation or conducted a significant amount of investigative work without any travel, and used data obtained from various sources to prepare this aircraft accident report.
HISTORY OF FLIGHT
On April 8, 2016, about 0914 Alaska daylight time, an amphibious float-equipped Cessna 206 airplane, N50159, sustained substantial damage after impacting snow-covered, rising terrain about 17 miles southeast of Angoon Airport, Angoon, Alaska. The airplane was being operated by Sunrise Aviation, Inc., Wrangell, Alaska, as a visual flight rules 14 Code of Federal Regulations (CFR) Part 135 commercial on-demand flight. The commercial pilot and two passengers sustained fatal injuries, and one passenger sustained serious injuries. Visual meteorological conditions existed at the airport at the time of departure, and company flight-following procedures were in effect. The flight departed from Wrangell Airport, Wrangell, Alaska, about 0810, destined for Angoon. The area between Wrangell and Angoon consists of remote inland fjords, coastal waterways, and steep mountainous terrain.
During an interview with the National Transportation Safety Board (NTSB) investigator-in-charge (IIC) 4 days after the accident, Sunrise Aviation's Director of Operations stated that, while flying another company airplane, he spoke with the accident pilot over the company radio frequency. The accident pilot commented to the director of operations that, while en route to Angoon, he was unable to make it through Pybus Bay due to low clouds and reduced visibility and that he was going to try an alternate route over lower terrain. The director of operations added that, about 15 to 20 minutes after speaking with the accident pilot, he landed in Wrangell and noticed that the Spidertracks signal for the accident airplane was stationary in an area of mountainous terrain. (As part of their company flight-following procedures, Sunrise Aviation incorporated Spidertracks, which provided company management personnel with a real-time, moving map display of an airplane's progress.) He then called personnel at the Angoon Airport and was told that the flight had not arrived. Shortly after attempting to reach the pilot on his cell phone and over the company radio frequency, he received a phone call from the Alaska Rescue Coordination Center notifying him that the 406-Mhz emergency locator transmitter (ELT) assigned to the accident airplane was transmitting a signal.
The Alaska Rescue Coordination Center notified the US Coast Guard (USCG) Air Station Sitka about the overdue airplane and the ELT signal transmitting along the accident pilot's anticipated flight route. About 1025, the USCG launched an MH-60 helicopter to search for the airplane. About 1054, the airplane's wreckage was located by a helicopter operated by Temsco Helicopters who then relayed the location to the USCG.
About 1117, the USCG crew located the airplane's wreckage in an area of steep mountainous, snow-covered terrain. However, due to hazardous weather and terrain conditions, the helicopter crew was unable to lower a rescue swimmer to the site, and the crew returned to Sitka to pick up rescue personnel from Sitka Mountain Rescue.
About 1355, the USCG helicopter crew returned to the accident site and landed the helicopter on an adjacent ridgeline. Members of Sitka Mountain Rescue and the USCG hiked to the accident site. Once on scene, they discovered that three of the airplane's occupants had died at the scene and that one occupant had survived the crash. The sole survivor was hoisted aboard the USCG helicopter and then transported to Juneau.
PERSONNEL INFORMATION
The pilot, age 60, held a commercial pilot certificate with airplane single-engine land and sea and instrument ratings. His most recent second-class medical certificate was issued on October 21, 2015, and contained the limitation that he must "possess glasses for near/intermediate vision."
No personal logbooks were located for the pilot. A review of company records revealed that the pilot had reported on his annual résumé, dated April 3, 2015, that his total flight experience was about 19,981 hours, 556 hours of which were in the previous 12 months.
AIRCRAFT INFORMATION
The airplane was a Cessna 206 manufactured in 1972, and it was equipped with a Continental Motors IO-550 series engine. At the time of its last annual inspection, completed on February 17, 2016, the airplane had 14,028 hours in service.
METEOROLOGICAL INFORMATION
At 0410, the National Weather Service Alaska Aviation Weather Unit issued an area forecast for central Southeast Alaska, including the accident site, which forecast scattered clouds at 800 ft mean sea level (msl) with a broken-to-overcast ceiling at 2,000 ft msl. Layered clouds were forecast from 2,000 ft msl through flight level 250. Occasional broken ceiling to 2,000 ft msl and light rain were forecast with isolated ceilings below 1,000 ft msl and visibility to 4 miles in light rain and mist. An AIRMET for mountain obscuration due to clouds and precipitation had also been issued and was valid at the accident site at the accident time.
The closest weather reporting facility was Angoon Airport, about 17 miles northwest of the accident site. At 0856, Angoon Airport issued a METAR that reported, in part, calm wind; sky condition, broken clouds at 500 ft, overcast at 1,800 ft; visibility 7 statute miles; temperature 45° F, dew point 45° F; and altimeter setting 29.71 inches of Mercury.
(Refer to the Meteorology Group Chairman's Factual Report in the public docket for further weather information and weather camera images).
WRECKAGE AND IMPACT INFORMATION
The wreckage was located in an open area of snow-covered rising terrain at an elevation of about 2,240 ft msl. The impact area was sloped about 27°. The airplane impacted terrain in a near-vertical, nose down attitude and sustained substantial damage to the fuselage and wings.
The right wing remained attached to the fuselage, and the leading edge exhibited extensive spanwise leading edge aft crushing. The right wing was displaced about 20° aft of the airplane's lateral axis.
The left wing remained attached to the fuselage at the forward attachment point and exhibited minor impact damage. The left wing was displaced about 40° forward of the airplane's lateral axis.
The horizontal stabilizer, elevators, vertical stabilizer, and rudder remained relatively free of impact damage. The elevator trim actuator was measured to be about 1.5 inches, consistent with a neutral setting.
The rudder and elevator primary flight control cables were continuous from the cockpit controls to their respective flight control surfaces. The aileron primary flight control cable continuities were confirmed from the cockpit controls to their respective flight control surfaces with cable separations at the wing root area. All cable separations exhibited signatures consistent with tensile overload and recovery cuts.
The fuselage exhibited crushing damage under the rudder pedals from the floor upward. The top of the fuselage was severed laterally the width of the cabin at the wing forward spar attachment points. The aft fuselage exhibited signatures consistent with stretching on the left side with the location corresponding to compression damage on the right side.
MEDICAL AND PATHOLOGICAL INFORMATION
The Alaska State Medical Examiner, Anchorage, Alaska, conducted an autopsy of the pilot. The cause of death for the pilot was attributed to "multiple blunt force injuries."
The FAA Bioaeronautical Sciences Research Laboratory performed toxicology testing of the pilot's specimens on July 06, 2016, which was negative for ethanol, drugs, and carbon monoxide.
TESTS AND RESEARCH
On October 18, 2016, an engine examination was performed by Continental Motors, Mobile, Alabama, under the supervision of the NTSB. Due to limited damage, an engine test run was conducted following the replacement of impact-damaged components. The engine was fitted with a test club propeller for the IO-550 series engine.
The engine started normally on the first attempt without hesitation or stumbling in the observed rpm. The engine rpm was advanced in steps for warm-up in preparation for full-power operation. The warm-up sequence was completed over 15 minutes before the engine throttle was advanced to the full-open position and then held for 5 minutes to stabilize. Throughout the test phase, the engine accelerated normally without any hesitation, stumbling, or interruption in power, and it demonstrated the ability to produce rated horsepower. During the engine test, the magnetos were checked, and a drop of 44 rpm was noted for the left magneto, and a drop of 32 rpm was noted for the right magneto.
ADDITIONAL INFORMATION
GPS Information
A Garmin 396 handheld GPS was found mounted on the instrument panel, and all cables were still attached. The unit was removed and sent to the NTSB Vehicle Recorders Laboratory, Washington, DC, for examination. Extracted GPS data for the accident flight included, in part, time, latitude, longitude, and GPS altitude. Groundspeed and course information were derived from the extracted parameters.
The GPS data indicated that the airplane departed Wrangell Airport at 1208:33 heading toward the southeast before turning to the northwest. The airplane continued on the northwesterly heading until crossing Beacon Point on Kupreanof Island and then turning west-northwest. The airplane continued on this heading until it entered Pybus Bay at 1,861 ft msl. The airplane then made four 360° turns, exited Pybus Bay while descending, and then leveled off about 215 ft msl. After exiting Pybus Bay, the airplane flew between Grave Island and Admiralty Island at 261 ft msl before entering Little Pybus Bay on a west-northwest heading at 940 ft msl. The airplane then turned 360° and continued heading west-northwest. The last recorded GPS data plot was at 1314:05 when the airplane was at 2,405 ft msl, heading 299°, and at 74 miles per hour.
A flight track map overlay and tabular data corresponding to the accident flight are available in the public docket for this accident.
NTSB Identification: ANC16FA017
Nonscheduled 14 CFR Part 135: Air Taxi & Commuter
Accident occurred Friday, April 08, 2016 in Angoon, AK
Aircraft: CESSNA 206, registration: N50159
Injuries: 3 Fatal, 1 Serious.
This is preliminary information, subject to change, and may contain errors. Any errors in this report will be corrected when the final report has been completed. NTSB investigators either traveled in support of this investigation or conducted a significant amount of investigative work without any travel, and used data obtained from various sources to prepare this aircraft accident report.
On April 8, 2016, about 0912 Alaska daylight time, an amphibious float-equipped Cessna 206 airplane, N50159, sustained substantial damage after impacting snow-covered, rising terrain about 17 miles southeast of the Angoon Airport, Angoon, Alaska. The airplane was operated by Sunrise Aviation, Inc., Wrangell, Alaska, as a visual flight rules (VFR) commercial on-demand flight under the provisions of 14 Code of Federal Regulations (CFR) Part 135. Of the four people on board, the commercial pilot and two passengers sustained fatal injuries, and one passenger sustained serious injuries. Visual meteorological conditions (VMC) prevailed at the time of departure, and company flight following procedures were in effect. The flight departed from the Wrangell Airport, Wrangell, about 0810, destined for Angoon.
The National Transportation Safety Board (NTSB) investigator-in-charge (IIC), along with another NTSB aircraft accident investigator and members of Juneau Mountain Rescue, reached the accident site on the morning of April 9. The wreckage was in an open area of snow-covered rising terrain, at an elevation of about 2,240 feet mean sea level (msl). The impact area was sloped about 27 degrees. The airplane impacted the snow in a near vertical attitude and sustained substantial damage to the fuselage and wings.
The area between Wrangell and Angoon consists of remote inland fjords, coastal waterways, and steep mountainous terrain.
As part of their company flight following procedures, Sunrise Aviation incorporates Spidertracks, which provides company management personnel with a real-time, moving map display of the airplane's progress. In addition, the accident airplane was equipped with a digital, 406 MHz ELT that instantly transmits a distress signal to search and rescue satellites, thereby alerting rescue personnel within minutes of the location of the crash.
During an interview with the NTSB IIC on April 12, the operator's director of operations stated that while flying another company airplane, he spoke with the accident pilot on a company radio frequency. The accident pilot commented to the director of operations that while en route to Angoon, he was unable to make it through Pybus Bay due to low clouds and reduced visibility, and that he was going to try an alternate route that had a lower terrain elevation. The director of operations added that about 15-20 minutes after speaking with the accident pilot, he landed in Wrangell and noticed the Spidertracks signal was stationary, in an area of mountainous terrain. He then called personnel at the Angoon airport and was told the flight had not arrived, and attempts to contact the accident pilot on his cell phone and aircraft radio were unsuccessful. Shortly thereafter, he received a phone call from the Alaska Rescue Coordination Center notifying him of a broadcasting 406 Mhz emergency locator transmitter (ELT) signal assigned to the accident airplane.
About 1025, after being notified of an overdue airplane, and after learning about reports of an emergency locator transmitter (ELT) signal along the accident pilot's anticipated flight route, search and rescue personnel from the U.S. Coast Guard Air Station Sitka launched an HH-60 helicopter to search for the airplane.
About 1054, the airplane's wreckage was located by a helicopter operated by Temsco Helicopters.
About 1117, the crew of a U.S. Coast Guard HH-60 helicopter located the airplane's wreckage in an area of steep mountainous, snow-covered terrain. However, due to hazardous weather and terrain conditions, the helicopter crew was unable to lower a rescue swimmer to the site, and the crew retuned to Sitka to pick up rescue personnel from Sitka Mountain Rescue.
About 1355, the HH-60 helicopter returned to the accident site and landed on an adjacent ridgeline, and members of Sitka Mountain Rescue and the Coast Guard hiked to the accident site. Once on scene, they discovered that three of the airplane's occupants died at the scene, and one had survived the crash. The sole survivor was hoisted aboard the Coast Guard HH-60 helicopter, and then transported to Juneau.
The airplane was equipped with a Continental Motors IO-550 series engine. A detailed examination is pending.
The closest weather reporting facility is Angoon Airport, about 17 miles northwest of the accident site. At 0956, an aviation routine weather report (METAR) from the Angoon Airport was reporting in part: Wind calm; sky condition, few clouds at 2,300 feet, broken clouds at 4,200 feet; visibility 10 statute miles; temperature 45 degrees F, dew point 43 degrees F; altimeter, 29.75 inHg.
The sole survivor of a Southeast Alaska plane crash that killed three people is now being treated at a Colorado hospital where her family describes her tale of recovery as "miraculous."
Ketchikan resident Morgan Enright, 21, is working with physical, occupational, and speech therapists daily. She had her first shower last weekend and is “happily eating and drinking throughout the day,” her mother posted on CaringBridge, a website for shared medical updates.
Chere Klein, Enright’s mom, said she’s not ready to speak publicly about her daughter’s experience in the April 8 crash but gave KTUU permission to write about it based on her CaringBridge posts.
Enright was on her way from Wrangell to Angoon for work when the Cessna 206 she was flying in crashed on Admiralty Island at 9:12 a.m. The plane went down in steep, snowy terrain about 17 miles southeast of Angoon, a mostly Tlingit community located in the coastal rainforest.
Pilot David Galla, 60, was killed along with passengers Greg Scheff, 61, and Thomas Siekawitch, 57. All three were from Wrangell.
The Coast Guard launched a helicopter from Sitka and located the plane’s wreckage at 11:17 a.m., according to the National Transportation Safety Board. The chopper couldn’t land due to hazardous weather.
At 1:55 p.m. the Coast Guard, along with Sitka Mountain Rescue, returned to try again. Ron Duvall, a volunteer with Sitka Mountain Rescue, was among the group of four first responders.
The helicopter dropped them off on a ridge, Duvall recalled in an interview today with Channel 2. Two rescuers hiked down to the crash site while the other two stayed above to watch for possible avalanches.
“We saw Morgan move her arms. We radioed back to the helicopter that there was a survivor,” Duvall said.
Duvall and his partner started removing gear and luggage strewn about the plane, along with the seat Enright was strapped in. When the two other rescuers arrived, they extracted her from the plane, which was nose down in the snow.
One person stabilized Enright's neck. Another held her hips while another stabilized her feet.
Duvall said, “Her eyes were not open. She was cold to the touch."
But she was alive.
After extracting her from the plane, Duvall and the team placed Enright in a Coast Guard basket along with a rescue swimmer. The helicopter hoisted her inside.
Enright was medevaced to Seattle’s Harborview Medical Center in critical condition.
Doctors placed her on dialysis to help her kidneys function. A ventilator assisted her with breathing.
Three days after the crash, Klein wrote that her daughter’s condition was precarious but that she was "steady."
“In her extremely critical condition this is very positive,” Klein wrote.
Enright began breathing on her own a week after the crash. When she would open her eyes, Enright recognized her family. She would squeeze hands when instructed by a nurse. Soon her brain pressure monitor was removed.
By April 20, 12 days after the crash, Enright moved to the acute care unit after having surgery on left leg two days earlier.
“She will need a skin graft in the near future but overall a stable day!” Klein posted on April 18.
When she was a bit more stable, Enright was able to sit in a gravity chair.
Earlier this month, Enright started eating ice chips and apple sauce, and drinking milk. On May 6, her mom posted that Enright’s kidneys were working again.
“Morgan said it’s time to celebrate with a Mimosa!” Klein wrote.
Harborview Medical Center discharged Enright to the care of a rehabilitation center in Englewood, Colo., on May 12 where she continues to improve.
Part of Enright’s recovery involves getting visits from a variety of therapy dogs.
“From Newfoundlands to mini-Schnauzers; many Golden Retrievers and Yellow Labs have snuggled right up in bed. Thank goodness for all the folks willing to share their special dogs!” Klein wrote.
A final NTSB report on the crash is expected to come out in early July. Meantime, Duvall, the rescuer, has been monitoring Enright’s progress on CaringBridge.
“I’m ecstatic. I’m dumbfounded," he said. "I’m not sure I could put a good adjective on the emotions that come with seeing her recover."
Story and photo gallery: http://www.ktuu.com
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