N9247C

HISTORY OF FLIGHTOn April 14, 2015, about 1330 Alaska daylight time (AKD), a wheel-equipped Cessna 180 airplane, N9247C, is presumed to have sustained substantial damage during impact with ocean waters, about 18 miles east of Whittier, Alaska, following a reported loss of engine power. The airplane was being operated as an instrument flight rules (IFR) cross-country personal flight under the provisions of Title 14 Code of Federal Regulations (CFR) Part 91, when the accident occurred. The instrument rated private pilot, the sole occupant of the airplane, sustained fatal injuries. Instrument meteorological conditions (IMC) prevailed along the route of flight, and the airplane was operating on an IFR flight plan. The flight departed the Wasilla Airport, Wasilla, Alaska, about 1205, en route to the Valdez Airport, Valdez, Alaska.

According to a family member the purpose of the flight was for the pilot to attend a business meeting.

The airplane was equipped with a Spidertracks flight tracking system, which provides real-time aircraft flight tracking data. The flight tracking information is transmitted via Iridium satellites to an internet based storage location, at 2-minute intervals. The airplane's last known location was near the eastern shoreline of Culross Island, at an altitude of 69 feet, traveling at 80 knots, on a heading of about 270 degrees.

An alert notice was issued by the Federal Aviation Administration (FAA) Kenai Flight Service Station at 1336 and a search was conducted by personnel from the U.S. Coast Guard, Alaska State Troopers, and Alaska Air National Guard, as well as a Good Samaritan vessel.

On April 15, about 1700, searchers located the remains of the pilot along the eastern shoreline of Culross Island. Also recovered was the left main landing gear strut and tire belonging to the accident airplane. The rest of the airplane has not yet been located, and it is presumed to have sunk in the ocean waters of Prince William Sound. PERSONNEL INFORMATIONThe pilot, age 53, held a private pilot certificate with airplane single engine land rating and instrument rating. His most recent third-class medical certificate was issued on August 06, 2013, and contained the limitation that he must wear corrective lenses for distant vision and possess glasses for near vision.

No personal logbooks were located for the pilot but according to a copy of FAA Form 8710-1, Airman Certificate and/or Rating Application, located at the home of the pilot, he had accumulated about 1605 total flight hours in airplanes as of July 11, 2014. AIRCRAFT INFORMATIONThe airplane was a Cessna 180, manufactured in 1955, and equipped with a Continental Motors O-470 series engine. The airplane was certified and current for flight under instrument flight rules, but was not certified for flight into known icing.

The colors of the airplane included a primary base color of white with blue and gold accent lines, white wings, and a blue propeller spinner.

At the time of its last annual inspection, completed on August 15, 2014, the airplane had 8,281.5 hours in service.

In a statement to the National Transportation Safety Board (NTSB) investigator-in-charge, a mechanic said the pilot discussed that when he applied carburetor heat, the control felt "mushy." The mechanic instructed him to inspect the control arm (item 34 in the Cessna Illustrated Parts Catalog) on the air box for any damage as it could prevent the carburetor heat from operating correctly. About 0830 on the day of the accident, the mechanic sent a text message to pilot to ask if he had checked the carburetor heat control, to which the pilot replied that he had not, but would do it that day.

The Cessna 180 Owner's Manual states, in part: "The carburetor air heat control is located to the left of the throttle. The push-pull control operates the carburetor air intake butterfly valve which proportions the hot and cold air entering the carburetor. Pulling the control out provides heated air for the carburetor while pushing the control all the way in provides only cold air for the carburetor."

A detailed diagram of the engine air intake system from the Cessna Illustrated Parts Catalog is located in the public docket for this accident. METEOROLOGICAL INFORMATIONThe forecast for the Portage Glacier area was for Marginal Visual Flight Rules conditions to prevail due to low ceilings and occasional IFR conditions due to low ceilings and visibility in snow showers. Moderate icing was forecasted between 4,000 feet agl and 10,000 feet agl with the freezing level beginning about 1,000 feet agl.

The closest weather reporting facility is Portage Glacier, Alaska, about 34 miles west of the accident site. At 1253, an aviation routine weather report (METAR) from the Portage Glacier Automated Surface Observation System (ASOS) was reporting in part: wind from 120° at 11 knots, gusting 26 knots; sky condition, vertical visibility 500 feet agl; visibility, 1/4 statute miles; temperature 32 degrees F; dew point 28 degrees F; altimeter, 29.54 inHg.

A detailed weather study is located in the public docket for this accident. AIRPORT INFORMATIONThe airplane was a Cessna 180, manufactured in 1955, and equipped with a Continental Motors O-470 series engine. The airplane was certified and current for flight under instrument flight rules, but was not certified for flight into known icing.

The colors of the airplane included a primary base color of white with blue and gold accent lines, white wings, and a blue propeller spinner.

At the time of its last annual inspection, completed on August 15, 2014, the airplane had 8,281.5 hours in service.

In a statement to the National Transportation Safety Board (NTSB) investigator-in-charge, a mechanic said the pilot discussed that when he applied carburetor heat, the control felt "mushy." The mechanic instructed him to inspect the control arm (item 34 in the Cessna Illustrated Parts Catalog) on the air box for any damage as it could prevent the carburetor heat from operating correctly. About 0830 on the day of the accident, the mechanic sent a text message to pilot to ask if he had checked the carburetor heat control, to which the pilot replied that he had not, but would do it that day.

The Cessna 180 Owner's Manual states, in part: "The carburetor air heat control is located to the left of the throttle. The push-pull control operates the carburetor air intake butterfly valve which proportions the hot and cold air entering the carburetor. Pulling the control out provides heated air for the carburetor while pushing the control all the way in provides only cold air for the carburetor."

A detailed diagram of the engine air intake system from the Cessna Illustrated Parts Catalog is located in the public docket for this accident. WRECKAGE AND IMPACT INFORMATIONThe only wreckage recovered to date is the left main landing gear strut and tire. The strut separated from the airplane with the gear box still attached. Sharp angular fractures exist on the forward and aft surface. The inboard surface separated at the rivet line with the outboard surface exhibiting a flat fracture surface. The fractures are consistent with damage that would occur during an impact sequence as opposed to tidal activity and impact with underwater objects after submersion.

Corrosion is present on the entire structure consistent with exposure to salt water. ADDITIONAL INFORMATION A pilot in an airplane about 6 minutes behind the accident airplane stated that while at 9,500 feet msl, in-flight visibility varied between 1 and 10 miles and was restricted by suspended ice crystals. The temperature was about 0°F. The pilot stated that prior to descending from 9,500 feet msl, he noticed a slight build-up of ice on the left engine cowling. COMMUNICATIONSA post accident review of archived FAA radar data and radio communication recordings revealed that, about 1315, the on-duty Anchorage (ZAN) Air Route Traffic Control Center (ARTCC) radar controller cleared the airplane for the LDA/DME H instrument approach to the Valdez Airport (VDZ). The airplane was about 60 miles southwest of VDZ, at an altitude of about 10,000 feet mean sea level (msl). Shortly after the pilot began a descent from 10,000 feet msl to 8,000 feet msl, he advised the ARTCC controller of an engine problem.

As a result of static and background noise on the air traffic recording, a variety of filters were applied to clarify the audio by the NTSB Vehicle Recorders Laboratory in Washington, DC. The transcription from that recording can be found in the public docket for this accident.

At 1316, after determining from the pilot that he did not have the VDZ weather, the ZAN controller issued the 1256 weather observation. One minute later, he cleared N9247C for the LDA/DME-H approach to VDZ with a restriction to cross the PEPPI intersection at or above 8000 feet. At 1318, the pilot reported leaving 10,000 feet for 8,000 feet.

At 1319, the pilot of N9247C stated that he was having trouble with his engine, but the transmission was blocked by other aircraft on the frequency. The controller acknowledged N9247C's descent from 10,000 to 8,000 feet, but did not acknowledge the pilot's report of engine trouble.

At 1321, the pilot transmitted, "Four seven charlie is declaring an emergency I have a problem with my engine I think I've been through the light stuff (unintelligible) descending for PEPPI for four thousand." The controller acknowledged the emergency call, then asked the pilot for the number of souls on board and if his engine was out or if he was able to continue. The pilot responded, "…I have windmilling power and (unintelligible) I'm in pretty poor shape. I still maintain forward airspeed. Descending for PEPPI at four thousand."

The controller replied, "…Roger, you're coming in a little bit scratchy right now. Right now I am showing you over an island you're about to head out over a little bit of w...