Sunday, September 10, 2017

Cessna 172 Skyhawk, N5703A: Accident occurred September 10, 2017 at Cavanaugh Bay Airport (66S), Coolin, Bonner County, Idaho

Aviation Accident Final Report - National Transportation Safety Board: https://app.ntsb.gov/pdf

Investigation Docket National Transportation Safety Board:  https://dms.ntsb.gov/pubdms/search/hitlist.cfm?docketID=60520&CFID=1376201&CFTOKEN=12b8337368a52a07-F4BC596C-E109-F45D-7AB069760E39B7BB

Location: Coolin, ID
Accident Number: GAA17CA526
Date & Time: 09/10/2017, 1444 PDT
Registration: N5703A
Aircraft: CESSNA 172
Aircraft Damage: Substantial
Defining Event: Loss of lift
Injuries: 1 Serious, 3 None
Flight Conducted Under: Part 91: General Aviation - Personal

Analysis

The pilot reported that he completed a normal landing to the south at a grass airstrip near a lake that was surrounded by 75-ft-tall pine trees. He added that he and his passengers ate lunch at the airstrip, and during that time, he noticed "mostly calm" wind with an "occasional gust from the south." The pilot further reported that, due to the runway gradient, he decided to take off downhill to the north because the wind sock was indicating a calm wind.

He reported that, during the soft field takeoff, the takeoff roll was normal, but that, about 100 ft above ground level, he noticed that the "climb had slowed" and the "airspeed was dropping." The pilot lowered the nose, the airplane "descended quickly," and then touched down on the runway with about 30 ft remaining. Subsequently, the airplane overran the runway, crossed a road, and impacted a dumpster and trees.

The fuselage and both wings sustained substantial damage.

The pilot reported that the airplane was 25 lbs under maximum gross weight.

The pilot reported that there were no preaccident mechanical malfunctions or failures with the airplane that would have precluded normal operation.

An automated weather observation station (AWOS) 13 nautical miles from the accident site, reported, about the time of the accident, wind from 240° at 6 knots. A review of four hourly AWOS recordings, south and east of the accident site, around the time of the accident, revealed that the wind was variable from the southwest to west at 5 to 10 knots, gusting 15 to 18 knots. The pilot reported that the takeoff was on runway 33. The calculated density altitude was 3,700 ft. According to the Federal Aviation Administration (FAA) density altitude Koch Chart, the airplane would have likely experienced a 32% decrease in the normal climb rate and a 50% increase in the normal takeoff distance.

The FAA's Pilot's Handbook of Aeronautical Knowledge, FAA-H-8083-25B, contained a section titled, "Effect of Obstructions on Wind," which stated in part:

"Another atmospheric hazard exists that can create problems for pilots. Obstructions on the ground affect the flow of wind and can be an unseen danger. Ground topography and large buildings can break up the flow of the wind and create wind gusts that change rapidly in direction and speed. These obstructions range from man-made structures, like hangars, to large natural obstructions, such as mountains, bluffs, or canyons. It is especially important to be vigilant when flying in or out of airports that have large buildings or natural obstructions located near the runway.

The intensity of the turbulence associated with ground obstructions depends on the size of the obstacle and the primary velocity of the wind. This can affect the takeoff and landing performance of any aircraft and can present a very serious hazard."

It is likely that, during the initial climb in high-density altitude conditions, the airplane encountered a quartering tailwind gust as the airplane climbed above the trees, which resulted in a loss of lift and an inability to gain altitude during the initial climb. 

Probable Cause and Findings

The National Transportation Safety Board determines the probable cause(s) of this accident to be:
The pilot's decision to take off in high-density altitude and gusting quartering tailwind conditions, which resulted in a loss of lift and an inability to gain altitude during the initial climb. 

Findings

Aircraft
Altitude - Attain/maintain not possible (Cause)

Personnel issues
Decision making/judgment - Pilot (Cause)

Environmental issues
Tailwind - Decision related to condition
Crosswind - Decision related to condition
Gusts - Decision related to condition
High density altitude - Decision related to condition
Tree(s) - Contributed to outcome

Factual Information

History of Flight

Initial climb
Other weather encounter
Loss of lift (Defining event)
Abnormal runway contact
Landing-landing roll
Runway excursion

Pilot Information

Certificate:Private
Age: 63, Male
Airplane Rating(s): Single-engine Land
Seat Occupied: Left
Other Aircraft Rating(s): None
Restraint Used: 4-point
Instrument Rating(s): None
Second Pilot Present: Yes
Instructor Rating(s): None
Toxicology Performed: No
Medical Certification: Class 3 With Waivers/Limitations
Last FAA Medical Exam: 12/16/2015
Occupational Pilot: No
Last Flight Review or Equivalent: 04/05/2016
Flight Time:  (Estimated) 325 hours (Total, all aircraft), 176 hours (Total, this make and model), 289 hours (Pilot In Command, all aircraft), 21 hours (Last 90 days, all aircraft), 9 hours (Last 30 days, all aircraft), 3 hours (Last 24 hours, all aircraft)
  
Pilot-Rated Passenger Information

Certificate: Private
Age: 71, Male
Airplane Rating(s): 
Seat Occupied: Right
Other Aircraft Rating(s): 
Restraint Used: 4-point
Instrument Rating(s): 
Second Pilot Present: Yes
Instructor Rating(s): 
Toxicology Performed: No
Medical Certification: None None
Last FAA Medical Exam: 
Occupational Pilot: No
Last Flight Review or Equivalent: 01/01/1987
Flight Time: (Estimated) 1008 hours (Total, all aircraft), 115 hours (Total, this make and model), 945 hours (Pilot In Command, all aircraft), 0 hours (Last 90 days, all aircraft), 0 hours (Last 30 days, all aircraft), 0 hours (Last 24 hours, all aircraft)
  
Aircraft and Owner/Operator Information

Aircraft Manufacturer: CESSNA
Registration: N5703A
Model/Series: 172 UNDESIGNATED
Aircraft Category: Airplane
Year of Manufacture: 1956
Amateur Built: No
Airworthiness Certificate: Normal
Serial Number: 28303
Landing Gear Type: Tricycle
Seats: 4
Date/Type of Last Inspection: 06/08/2017, Annual
Certified Max Gross Wt.: 2200 lbs
Time Since Last Inspection:  
Engines: 1 Reciprocating
Airframe Total Time: 2810 Hours at time of accident
Engine Manufacturer: CONT MOTOR
ELT: C91  installed, not activated
Engine Model/Series: O-300
Registered Owner: On file
Rated Power: 145 hp
Operator: On file
Operating Certificate(s) Held: None

Meteorological Information and Flight Plan

Conditions at Accident Site: Visual Conditions
Condition of Light: Day
Observation Facility, Elevation: KSZT, 2131 ft msl
Observation Time: 2155 UTC
Distance from Accident Site: 16 Nautical Miles
Direction from Accident Site: 140°
Lowest Cloud Condition: Clear
Temperature/Dew Point: 23°C / 3°C
Lowest Ceiling: None
Visibility:  10 Miles
Wind Speed/Gusts, Direction: 6 knots, 240°
Visibility (RVR): 
Altimeter Setting: 30.21 inches Hg
Visibility (RVV): 
Precipitation and Obscuration: No Obscuration; No Precipitation
Departure Point: Coolin, ID (66S)
Type of Flight Plan Filed: None
Destination: SPOKANE, WA (SFF)
Type of Clearance: VFR
Departure Time: 1445 PDT
Type of Airspace: Class G

Airport Information

Airport: CAVANAUGH BAY (66S)
Runway Surface Type: Grass/turf
Airport Elevation: 2484 ft
Runway Surface Condition: Dry
Runway Used: 33
IFR Approach: None
Runway Length/Width: 3100 ft / 120 ft
VFR Approach/Landing: None

Wreckage and Impact Information

Crew Injuries: 2 None
Aircraft Damage: Substantial
Passenger Injuries: 1 Serious, 1 None
Aircraft Fire: None
Ground Injuries: N/A
Aircraft Explosion: None
Total Injuries: 1 Serious, 3 None
Latitude, Longitude: 48.518611, -116.822222 (est)

Additional Participating Entity:
Federal Aviation Administration / Flight Standards District Office; Spokane, Washington


Aviation Accident Factual Report - National Transportation Safety Board: https://app.ntsb.gov/pdf

http://registry.faa.gov/N5703A

NTSB Identification: GAA17CA526
14 CFR Part 91: General Aviation
Accident occurred Sunday, September 10, 2017 in Coolin, ID
Aircraft: CESSNA 172, registration: N5703A
Injuries: 1 Serious, 3 Uninjured.

NTSB investigators used data provided by various entities, including, but not limited to, the Federal Aviation Administration and/or the operator and did not travel in support of this investigation to prepare this aircraft accident report.

The pilot reported that he completed a normal landing to the south at a grass airstrip, near a lake and surrounded by 75 ft. tall pine trees. He added that he and his passengers ate lunch at the airstrip, and during that time, he noticed "mostly calm" wind with an "occasional gust from the south." The pilot further reported that, due to the runway gradient, he decided to takeoff downhill to the north, as the windsock was indicating a calm wind.

During the soft field takeoff, he reported that the take-off roll was normal, but about 100 ft. above ground he noticed that the "climb had slowed" and the "airspeed was dropping." The pilot lowered the nose, the airplane "descended quickly," and touched down on the runway with about 30 ft. remaining. Subsequently, the airplane overran the runway, crossed a road, and impacted a dumpster and trees.

The fuselage and both wings sustained substantial damage. 

The pilot reported that the airplane was 25 lbs. under maximum gross weight. 

The pilot did not report that there were any preaccident mechanical malfunctions or failures with the airplane that would have precluded normal operation.

An automated weather observation station (AWOS), about the time of the accident, 13 nautical miles from the accident site, reported wind from 240° at 6 knots. A review of four, hourly AWOSs, south and east of the accident site, around the time of the accident, recorded wind variable from the southwest to westerly direction, at 5 to 10 knots, gusting 15 to 18 knots. The pilot reported that the takeoff was on runway 33. The calculated density altitude was 3,700 ft. According to the Federal Aviation Administration density altitude Koch Chart, the airplane would have likely experienced a 32% decrease to the normal climb rate, and a 50% increase to the normal takeoff distance. 

The Federal Aviation Administration's Pilot's Handbook of Aeronautical Knowledge, FAA-H-8083-25B, contains a section titled "Effect of Obstructions on Wind" which stated in part:

"Another atmospheric hazard exists that can create problems for pilots. Obstructions on the ground affect the flow of wind and can be an unseen danger. Ground topography and large buildings can break up the flow of the wind and create wind gusts that change rapidly in direction and speed. These obstructions range from man-made structures, like hangars, to large natural obstructions, such as mountains, bluffs, or canyons. It is especially important to be vigilant when flying in or out of airports that have large buildings or natural obstructions located near the runway.

The intensity of the turbulence associated with ground obstructions depends on the size of the obstacle and the primary velocity of the wind. This can affect the takeoff and landing performance of any aircraft and can present a very serious hazard."




COOLIN, Idaho - A Cessna 172 with four people onboard crashed while taking off from the Cavanaugh Bay Airport around 2:45 p.m. on Sunday near the south banks of Priest Lake.

The Spokane pilot and his three passengers walked away from the crash with minor injuries.

The pilot told KXLY he encountered windshear (a phenomenon that can affect a plane's airspeed) during takeoff. He declined to provide any further comments.

Witnesses described seeing a plane struggling to takeoff. At one point, the plane pitched 90 degrees, struck its wing on the pavement and slid across Cavanaugh Bay road on its nose. The Cessna came to a stop feet away from a propane tank and several buildings. 

"The fact that they walked out of there alive was amazing," said Gena Costa, who was bartending in a restaurant nextdoor to the crash site. Employees and customers rushed to help those inside. Costa said one man had a cut on his head.

"I'm so happy that they are alive," said Costa. "To see the actual collision and crash in front of your eyes, it's just crazy. How did they live?"

Story and video ➤  http://www.kxly.com




COOLIN, Idaho -  Firefighters are investigating after a small plane crashed near Priest Lake in Coolin, Idaho, Sunday afternoon.

Coolin Fire Chief Peggy Smith reports four people were in the plane when it crashed trying to take off from a grass air strip at Cavanaugh Bay. Smith says there were minor injuries as a result of the crash, but no one was taken to the hospital. 

The plane landed nose down up against a fence.

The cause of the crash is still under investigation Sunday.

Original article can be found here ➤ http://www.khq.com

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