Wednesday, December 28, 2016

San Diegans are tired of airport noise and tired of complaining

Point Loma, Mission Beach and La Jolla residents at an Airport Noise Advisory Committee meeting on Dec. 21, 2016. 



Even the most prolific complaint writer is fatigued.


Steve Crow, a Point Loma Heights resident of 10 years, complained about airplane noise far more than anyone else in 2016, filing 20,068 complaints. In February alone, he filed 4,084 complaints, as many as 251 in a day. In November, he lodged 39.


"It really just started two years ago," Crow said about planes flying over his neighborhood. "But I've stopped logging complaints because it wears on you."


Crow was working from home when he began submitting hundreds of complaints a day. He said he made calls to city council members and local politicians only to receive a "stock response" each time.


"You're up against an industry and you're just residents, that's all you are," he said. "You've got to dedicate time to something else. Do you move? Yeah, probably. I don't want to, but there's just not going to be a resolution."


An airport authority spokeswoman said an improvement in operations is responsible for the recent downturn in complaints, as well as heightened community awareness of flight paths and daily airport operations.


Explaining the increase

In late 2015, complaints began to rise from several a month to thousands as the Federal Aviation Administration rolled out its plan for the SoCal Metroplex, a project that would alter arrival and departure flight paths at 19 Southern California airports.

For San Diego, the proposal meant departing planes, after taking off toward the west, would turn sooner and fly closer to previously quiet neighborhoods. However, after months of negative feedback from the community, the FAA placed the turning point almost two miles south of the peninsula, farther south than its current location.

Airport authority spokeswoman Rebecca Bloomfield said there were no actual changes in airport operations at the time, and it was the proposal that caused an immediate increase in noise complaints.

Documents provided by the airport authority tell a different story. They show early turns below 6,000 feet and curfew violations, two main causes for noise in Point Loma and nearby neighborhoods, have increased since 2014.

"When they say there was no change, that worries me," said Casey Schnoor, a member of an airport noise subcommittee. "When you look at the data, things were changing."

Early turns occur when air traffic controllers either instruct a pilot to turn before reaching an established waypoint, or approve a pilot's request to do so. The points were created to keep flights on a route straight off the peninsula and around it to avoid unnecessary noise while taking off.

At a November airport noise meeting, FAA officials said controllers allow early turns for three reasons: weather, safety, and most concerning for the committee members, distance between planes, known as separation.

Dr. Lila Schmidt, a physician and Point Loma resident, told FAA officials in November that spacing planes out will cut down on noise, "but you won't have as much money coming into San Diego."

She suggested air traffic control - responsible for incoming and outgoing flights on the runway - only permit flights to depart every five minutes, which she said would allow planes to avoid bunching up and would reduce early turns.

In response, Barry Davis, an air traffic manager for the FAA, told her "that will never happen" because passengers will have to wait too long on the runway before taking off.

In a recent report, inewsource found airlines are paying an increasing number of fines for breaking the Airport Authority rule that says planes can't take off between 11:30 p.m. and 6:30 a.m.

Although fines are higher and more frequent than in previous years, violations have increased from 47 in 2014 to 55 through November of this year.

How the airport authority responds

"There's only so many things the airport can do," airport authority spokeswoman Bloomfield said. The takeoff curfew is not an FAA rule.

Bloomfield told inewsource the authority can only make recommendations to the FAA, air traffic control and airlines on issues like early turns and curfew violations. She said once flights are on the runway, the FAA is in charge. Air traffic control directs planes on when to depart and when it is safe to make a turn.

The airport authority can't stop flights from taking off after 11:30 p.m., but it can levy fines of up to $30,000 if the local rule is broken, Bloomfield said, and airlines have long been aware of the curfew.

To combat community concern over noise, the airport authority recently increased the frequency of airport noise meetings from quarterly to every other month and created a subcommittee allowing the public to communicate directly with FAA officials.

But community members who continue to submit noise complaints say that effort may not be enough.

"Every meeting we get told, 'we'll look into it,'" Schmidt said. "I just want to hear 'we fixed it.'"

Reed more here:  http://www.cbs8.com

Allegiant Air apologizes for diverted Ogdensburg flight

OGDENSBURG - Allegiant Air has offered an apology to passengers for a Christmas Eve flight originally bound from Ogdensburg to Florida that was forced to land in Syracuse because of a mechanical problem.

A spokeswoman for Allegiant Air confirmed that the Dec. 24 flight from Ogdensburg experienced a midair mechanical problem that forced the pilot to land at Hancock International Airport in Syracuse.

Allegiant Air Flight 1711 departed Ogdensburg at 12:40 p.m. enroute to Fort Lauderdale-Hollywood International Airport when the flight’s captain made a decision to reroute the plane to Syracuse, according to Allegiant Air Spokeswoman Krysta Levy.

“The aircraft experienced a mechanical issue in flight, and the captain diverted to Syracuse Hancock International Airport,” Ms. Levy said in a statement. “The aircraft landed safely and was met by airport fire crews as a precaution.”

The Allegiant Air spokeswoman did not elaborate on the nature of the mechanical issue that forced the diversion of Flight 1711.

Ms. Levy said there were 160 passengers and six crew members on the flight, and that all of those on board deplaned safely at the Syracuse terminal gate.

A replacement aircraft was dispatched to carry the passengers on to their final Fort Lauderdale destination, according to Ms. Levy. She said the passengers landed in Fort Lauderdale at 8:45 p.m. local time on Christmas Eve.

She said the airline apologized to the passengers for the disruption of service. “We sincerely apologize to our passengers for the inconvenience and disruption to their plans,” Ms. Levy said. “Passengers were provided $100 vouchers for future travel on Allegiant as well as food service in the gate area.”

Ogdensburg Bridge and Port Authority Executive Director Wade A. Davis praised Allegiant Air for its handling of the Christmas Eve incident, and the role the airline is playing in helping spur economic activity in the region. “Ogdensburg International Airport is accomplishing great things for the local economy and safety in aviation is number one,” Mr. Davis said in an email. “OGS commends the professionalism of Allegiant to make the right calls to keep the traveling public safe. Thanks to these professionals, flights out of OGS are operated safely and efficiently.”

Story and comments:  http://www.watertowndailytimes.com

Ogdensburg International Airport close to getting $1 million from FAA for having 10,000 outbound passengers

OGDENSBURG -- The Ogdensburg Bridge and Port Authority is close to winning a $1 million bonus from the Federal Aviation Administration that they are all but calling it a done deal.

“We’re forecasting 10,225 enplanements” for the year at Ogdensburg International Airport, said OBPA Executive Director Wade Davis on Wednesday, which would exceed the 10,000 passengers on outbound flights in 2016 that the FAA said would be needed to claim the big bonus.

“We’re going to be very close,” Davis said.

If they don’t make 10,000 enplanements their bonus will be $150,000 that the OBPA can use for airfield improvements and equipment purchases.

Davis wouldn’t give us an exact number as of today, but with three Allegiant Air flights to Florida through Saturday of about 150 passengers each and up to 27 passengers a day with Cape Air flights to Albany and Boston, he was comfortable with the 10,225 number by midnight Saturday night, “depending on weather,” Davis said.

A promotion the OBPA announced in November will account for 150 passengers. Anyone traveling on Allegiant and Cape Air out of Ogdensburg who bought two or more outbound tickets at once would get a “two-for-one” ticket deal, and as of Wednesday, about 150 ticket buyers had taken advantage of that.

“We have not hit 10,000 yet, but we are on track,” he said. “We’ve never hit that number. We’re very excited about it.”

“The weather in the North Country is certainly a concern, so I don’t want to say we’ll get there for certain, but we’re fairly sure we’ll make it,” Davis said.

A runway extension completed this year allows Allegiant jets to land and take off from Ogdensburg, so the airline started up their low-cost flights to Florida from the airport. Money was also put into improvements to the terminal building and parking areas.

On Dec. 24, an Allegiant Ogdensburg-to-Ft. Lauderdale flight made an unscheduled landing in Syracuse.  Davis referred questions about the incident to Allegiant public relations staff who did not immediately respond to a request for comment.

However, WWNY reported the plane suffered mechanical problems of an undisclosed nature and passengers were transferred to another plane to complete their journey.

Source:   http://northcountrynow.com

Cessna 172B Skyhawk, N6941X: Accident occurred December 28, 2016 near Sauk Prairie Airport ( 91C), Prairie du Sac, Sauk County, Wisconsin

The National Transportation Safety Board did not travel to the scene of this accident.

Additional Participating Entity:

Federal Aviation Administration / Flight Standards District Office; Milwaukee, Wisconsin

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

Investigation Docket - National Transportation Safety Board: https://dms.ntsb.gov/pubdms

http://registry.faa.gov/N6941X

Location: Prairie Du Sac, WI
Accident Number: CEN17LA090
Date & Time: 12/28/2016, 1230 CST
Registration: N6941X
Aircraft: CESSNA 172B
Aircraft Damage: Substantial
Defining Event: Loss of control on ground
Injuries: 2 None
Flight Conducted Under: Part 91: General Aviation - Personal

Analysis 

The private pilot was conducting a local flight. He reported that, during the flight, the engine started to run roughly. He decided to return to the airport for a precautionary landing. About 4 miles from the airport and while lined up for landing, the pilot increased the engine throttle with no response; the airplane lost total power. He decided to land the airplane on a roadway about 1 mile from the airport. After landing on the roadway and coming to a complete stop, the pilot restarted the engine and attempted to taxi off the roadway. While he was taxiing the airplane, it struck three roadway signs and a fence, which resulted in structural damage to the left wing.

After the airplane was recovered, small amounts of water were present in the fuel from both wing sumps and the gascolator. The engine was started, ran normally, and both magnetos checked within normal limits. The loss of engine power could have resulted from water in the fuel but the definitive reason could not be determined.

Although the pilot landed the airplane successfully on the roadway after having engine power problems, his decision to taxi the airplane from the roadway and his failure to avoid the roadway signs and fence resulted in substantial damage to the airplane. 

Probable Cause and Findings

The National Transportation Safety Board determines the probable cause(s) of this accident to be:
The pilot's decision to taxi the airplane from the roadway and his subsequent failure to maintain clearance from signs and a fence after a successful emergency landing following a total loss of engine power.

Findings

Aircraft
Fuel - Fluid type
Fuel - Fluid condition

Personnel issues
Decision making/judgment - Pilot (Cause)
Monitoring environment - Pilot (Cause)

Environmental issues
Tree(s) - Effect on operation
Sign/marker - Effect on operation

Factual Information 

On December 28, 2016, about 1230 central standard time, a Cessna 172B single engine airplane, N6941X, registered to a private individual, sustained substantial damage after it struck roadway signs while attempting to taxi after a successful emergency landing near Prairie Du Sac, Wisconsin. The private pilot and one passenger were not injured. The flight was being conducted under the provisions of Federal Code of Regulations Part 91. Visual meteorological conditions prevailed throughout the area and a flight plan was not filed. The flight originated from the Sauk-Prairie Airport (91C), Prairie Du Sac, Wisconsin about 1130.

The pilot reported that he was flying locally at 4,500 feet after departing from 91C. The engine started to run rough and the pilot applied carburetor heat. He decided to return to the airport for a precautionary landing. About 4 miles from the airport, and lined up for landing on runway 18, the pilot increased the engine throttle but had no response. He decided to land on a roadway about 1 mile from the airport.

After landing on the roadway and coming to a stop, the pilot started the engine and attempted to taxi off the roadway. While taxiing, the airplane struck 3 road signs and an iron fence, resulting in structural damage to the left wing.

The local Sheriff closed the highway as the airplane was loaded onto a trailer and transported to 91C where it was examined by an FAA inspector. Approximately 4-5 gallons of fuel were present in each wing tank. Small amounts of water were present in the fuel from both wing sumps and the gascolator. The engine was started, ran normally, and both magnetos checked within normal limits. The fuel appeared to be automotive fuel. The pilot confirmed that he used automotive fuel. Review of the logbooks did not disclose that the airplane was approved for the use of automotive fuel.

History of Flight

Taxi
Collision with terr/obj (non-CFIT)
Loss of control on ground (Defining event)

Pilot Information

Certificate: Private
Age: 69, Male
Airplane Rating(s): Single-engine Sea
Seat Occupied: Left
Other Aircraft Rating(s): None
Restraint Used: 4-point
Instrument Rating(s): None
Second Pilot Present: No
Instructor Rating(s): None
Toxicology Performed: No
Medical Certification: Class 3 With Waivers/Limitations
Last FAA Medical Exam: 04/06/2016
Occupational Pilot: No
Last Flight Review or Equivalent: 08/22/2016
Flight Time:  (Estimated) 3401 hours (Total, all aircraft), 3401 hours (Total, this make and model), 3401 hours (Pilot In Command, all aircraft), 9 hours (Last 90 days, all aircraft), 3 hours (Last 30 days, all aircraft), 1 hours (Last 24 hours, all aircraft) 

Aircraft and Owner/Operator Information

Aircraft Make: CESSNA
Registration: N6941X
Model/Series: 172B B
Aircraft Category: Airplane
Year of Manufacture: 1960
Amateur Built: No
Airworthiness Certificate: Normal
Serial Number: 17247841
Landing Gear Type: Tricycle
Seats: 4
Date/Type of Last Inspection: 01/28/2016, Annual
Certified Max Gross Wt.: 2299 lbs
Time Since Last Inspection:
Engines: 1 Reciprocating
Airframe Total Time: 6357 Hours at time of accident
Engine Manufacturer: CONT MOTOR
ELT: C91  installed, not activated
Engine Model/Series: O-300 SER
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: MSN
Distance from Accident Site: 15 Nautical Miles
Observation Time: 1155 CST
Direction from Accident Site: 260°
Lowest Cloud Condition: Thin Broken / 13000 ft agl
Visibility:  10 Miles
Lowest Ceiling: Overcast / 20000 ft agl
Visibility (RVR):
Wind Speed/Gusts: 10 knots /
Turbulence Type Forecast/Actual: / None
Wind Direction: 210°
Turbulence Severity Forecast/Actual: /
Altimeter Setting: 29.74 inches Hg
Temperature/Dew Point: 2°C / -3°C
Precipitation and Obscuration:
Departure Point: Prairie Du Sac, WI (91C)
Type of Flight Plan Filed: None
Destination: Prairie Du Sac, WI (91C)
Type of Clearance: None
Departure Time: 1130 CST
Type of Airspace: Class E

Airport Information

Airport: Sauk-Prairie Airport (91C)
Runway Surface Type: N/A
Airport Elevation: 832 ft
Runway Surface Condition: Dry
Runway Used: N/A
IFR Approach: None
Runway Length/Width:
VFR Approach/Landing: None 

Wreckage and Impact Information

Crew Injuries: 1 None
Aircraft Damage: Substantial
Passenger Injuries: 1 None
Aircraft Fire: None
Ground Injuries: N/A
Aircraft Explosion: None
Total Injuries: 2 None
Latitude, Longitude:  43.297778, -89.755833 (est)

NTSB Identification: CEN17LA090
14 CFR Part 91: General Aviation
Accident occurred Wednesday, December 28, 2016 in Prairie Du Sac, WI
Aircraft: CESSNA 172B, registration: N6941X
Injuries: 2 Uninjured.

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 may not have traveled in support of this investigation and used data provided by various sources to prepare this aircraft accident report.

On December 28, 2016, about 1230 central standard time, a Cessna 172B single engine airplane, N6941X, registered to a private individual, sustained substantial damage after it struck roadway signs while attempting to taxi after a successful emergency landing. The private pilot and one passenger were not injured. The flight was being conducted under the provisions of Federal Code of Regulations Part 91. Visual meteorological conditions prevailed throughout the area and a flight plan was not filed. The flight originated from the Prairie Du Sac Airport (91C) about 1130.

The pilot reported that he was flying locally at 4,500 feet after departing from 91C. The engine started to run rough and the pilot applied carburetor heat. He decided to return to the airport for a precautionary landing. About 4 miles from the airport, and lined up for landing on runway 18, the pilot increased the engine throttle, but had no response. He decided to land the airplane on US Highway 12, about 1 mile from the airport. After landing on the roadway and coming to a stop, the pilot started the engine and attempted to taxi off the roadway. While taxiing, the airplane struck 3 road signs and an iron fence, resulting in structural damage to the left wing.

The local Sheriff closed the highway as the airplane was loaded onto a trailer and transported to 91C where it was examined by an FAA inspector. Approximately 4-5 gallons of fuel were present in each wing tank. Small amounts of water were present in the fuel from both wing sumps and the gascolator. The engine was started, ran normally, and both magnetos checked within normal limits. The fuel appeared to be automotive fuel.

The pilot confirmed that he used automotive fuel. Initial review of the logbooks did not disclose that the airplane was approved for the use of automotive fuel.





PRAIRIE DU SAC – No one was injured Wednesday when a plane made an emergency landing on U.S. Highway 12 near the Sauk Prairie Airport.

At about 12:30 p.m., a southbound 1961 single-engine Cessna headed to the airport lost power over the Baraboo Bluffs, prompting the pilot to land unexpectedly. The plane touched down on Highway 12's southbound lanes near the intersection with Sauk County Highway Z.

The pilot, 69-year-old pilot Stephan L. Arnold of Madison, restored power after the landing and attempted to take off, but hit a road sign, causing the plane to cross the median and come to rest on the east side of U.S. 12 next to Sauk Prairie Cemetery. Arnold and his passenger were unhurt.

A pair of witnesses, Anthony Kirkus and wife Meg of Wisconsin Dells, were driving north on U.S. 12 when they saw the plane headed for their car’s windshield.

Kirkus said “the plane touched down right as we passed it going the other way, it was crazy.”

The plane did not show any outward signs of having a problem, aside from flying extremely low, Kirkus said. “Just before it landed, we saw this low-flying plane that almost hit a set of wires going across the highway,” Kirkus said. “It just missed that and then we said, ‘Well, this is definitely landing on Highway 12.’”

Deputies directed vehicles around the landing site Wednesday afternoon, temporarily slowing traffic on U.S. 12. The plane sustained moderate damage and was towed to the airport.

The Sheriff’s Office was assisted by several agencies, including Sauk City Fire, Sauk Prairie EMS, Sauk Prairie Police, the county Highway Department, the state Department of Transportation and the Federal Aviation Administration.

Source:   http://www.wiscnews.com




SAUK CITY, Wis. - The Sauk County Sheriff's Department said a plane made an emergency landing on U.S. Highway 12 just north of Sauk City on Wednesday afternoon.

Two people were in the aircraft when the plane made the landing just before 12:30 p.m. Wednesday, according to the sheriff's department. No injuries were reported.

A sheriff's chief deputy told News 3 that the plane had taken off from the Sauk-Prairie Airport in Prairie Du Sac.

The pilot, a Madison man, told deputies he lost power and landed on the road. When he regained power, he tried to take off again and hit a sign post, the official said. There was some damage to the plane, which was being towed back to the airport Wednesday afternoon.

The highway where the plane landed is just north of an airport outside of Sauk City.

A stretch of Highway 12 was closed briefly after the landing but was reopen before about 1 p.m., officials said.


Source:   http://www.channel3000.com















Anthony Kirkus was driving, his wife, Meg, was in the passenger seat, and an airplane was headed for their car's windshield.

This was Wednesday just after noon as the couple was driving north on Highway 12 near Highway Z outside of Prairie Du Sac, adjacent to Sauk Prairie Airport and a cemetery.

"The plane touched down right as we passed it going the other way. It was crazy," said Kirkus, who lives in Wisconsin Dells.

Stephen L. Arnold, of Madison, was operating the 1960 single-engine Cessna when the plane lost power, prompting the emergency landing, the Sauk County Sheriff's Office said. Arnold and a passenger were not injured, the Sheriff's Office said.

"Just before it landed, we saw this low-flying plane that almost hit a set of wires going across the highway," Kirkus said. "It just missed that and then we said, 'Well, this is definitely landing on Highway 12.'"

"It was coming straight at us, and I thought a little optimistically that it was going to land nearby because it was not really lining up with us and then it came down," he said.

Arnold, 69, attempted to take off from the highway after the plane regained power, the Sheriff's Office said. But the aircraft struck a road sign, sending it over the median before stopping on the east side of the highway.

The moderately damaged plane was towed to the nearby airport, the Sheriff's Office said.

Source:  http://host.madison.com

Columbia LC42-550FG, N1222G: Accident occurred December 08, 2016 in Singapore, Singapore

AIRCRAFT GUARANTY CORP TRUSTEE:   http://registry.faa.gov/N1222G

NTSB Identification: WPR17WA040
Accident occurred Thursday, December 08, 2016 in Singapore, Singapore
Aircraft: CESSNA 350, registration: N1222G
Injuries: 2 Uninjured.

The foreign authority was the source of this information.

On December 8, 2016, about 1743 local time, a Cessna 350, N1222G, had the brakes catch fire during taxi following an aborted takeoff at Seletar Airport, Singapore. The owner/pilot was operating the airplane under the provisions of the Singapore Civil Aviation Regulations.

Preliminary information received from the government of Singapore indicated that the pilot had rejected the takeoff above 70 knots, and was taxiing back to the parking bay. During the taxi, the pilot felt as though he had lost brake authority. The airplane departed the taxiway center line, and started veering to the left. The pilot then applied the left brake as he was heading towards a parked Cessna 172. The airplane turned 180 degrees, and ended up taxiing towards another jet aircraft that was being towed into a parking bay opposite the Cessna 172. The pilot applied the left brake again, and came to a halt in the middle of Taxiway WB5. The main landing gears caught fire; the fire was subsequently extinguished. There was significant heat damage at the belly and the main landing gears of the airplane.

The accident is under the jurisdiction of and is being investigated by the Transport Safety Investigation Bureau (TSIB) of Singapore. As the State of Manufacture of the airplane and engines, the NTSB has designated a U.S. accredited representative to assist the TSIB in its investigation.

All inquiries concerning this accident should be directed to the TSIB of Singapore:

Transport Safety Investigation Bureau (TSIB)
#048-058 Passenger Terminal Building 2
Singapore Changi Airport
Singapore 819634

This report is for information purposes only, and contains only information obtained for, or released by, the government of Singapore.

Cessna 195 Businessliner, N4426C: Incident occurred July 21, 2018 in Lexington, Lafayette County, Missouri and Incident occurred January 10, 2017 at Field's Field Airport (7TA0), Tomball, Harris County, Texas

Federal Aviation Administration / Flight Standards District Office; Kansas

July 21, 2018:  Attempted emergency landing, overshot the runway and landed in a field.

http://registry.faa.gov/N4426C

Date: 21-JUL-18
Time: 19:45:00Z
Regis#: N4426C
Aircraft Make: CESSNA
Aircraft Model: 195
Event Type: INCIDENT
Highest Injury: NONE
Aircraft Missing: No
Damage: UNKNOWN
Activity: UNKNOWN
Flight Phase: EMERGENCY DESCENT (EMG)
Operation: 91
City: LEXINGTON
State: MISSOURI
Country: UNITED STATES

January 10, 2017: Aircraft on landing, went off the runway into a ditch.

Federal Aviation Administration / Flight Standards District Office; Denver

Date: 10-JAN-17
Time: 19:07:00Z
Regis#: N4426C
Aircraft Make: CESSNA
Aircraft Model: C195
Event Type: INCIDENT
Highest Injury: NONE
Aircraft Missing: No
Damage: MINOR
Activity: UNKNOWN
Flight Phase: LANDING (LDG)
City: TOMBALL
State: TEXAS

Maule MX-7-235 Star Rocket, N56681, Barry L. Stanley/Kirsten E. Stanley dba Denali Flying Service: Accident occurred December 15, 2016 in Willow, Alaska

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

Investigation Docket  - National Transportation Safety Board: https://dms.ntsb.gov/pubdms

Aviation Accident Data Summary - National Transportation Safety Board:  https://app.ntsb.gov/pdf


Additional Participating Entity:
Federal Aviation Administration / Flight Standards District Office; Anchorage, Alaska

http://registry.faa.gov/N56681

NTSB Identification: GAA17CA101
Nonscheduled 14 CFR Part 135: Air Taxi & Commuter
Accident occurred Thursday, December 15, 2016 in Willow, AK
Probable Cause Approval Date: 06/07/2017
Aircraft: MAULE MX 7, registration: N56681
Injuries: 1 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 of the tailwheel-equipped airplane reported that, during takeoff from a remote airstrip, the airplane impacted a snowdrift and was “launched” into the air. Subsequently, he heard something break. He added that the airplane appeared to be fine with no indications of a problem other than the left tire “looked a little off.” The pilot returned to his original departure airport without further incident. 

During a postaccident examination, his mechanic discovered that the tubing in the bottom of the fuselage where the oleo strut attached to the main landing gear was broken. 

The pilot reported no preaccident mechanical malfunctions or failures with the airplane that would have precluded normal operation.
As a safety recommendation, the pilot added that walking the runway before takeoff might have revealed the snowdrift.

The National Transportation Safety Board determines the probable cause(s) of this accident as follows:
The pilot’s failure to ensure that the runway was clear of any obstacles before departure, which resulted in the airplane impacting a snowdrift.

The pilot of a tailwheel-equipped airplane reported that during takeoff from a remote airstrip, the airplane impacted a snowdrift and was "launched" into the air. Subsequently, he heard something break. He added that the airplane appeared to be fine with no indications of a problem other than the left tire "looked a little off". The pilot returned to his original departure airport without further incident. 

During a post-accident examination, his mechanic discovered that the tubing in the bottom of the fuselage where the olio strut attached to the main landing gear was broken. 

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

As a safety recommendation, the pilot added that walking the runway prior to takeoff might have revealed the snowdrift.

Robinson R22 BETA, N7095A: Accident occurred February 18, 2017 in Holbrook, Navajo County, Arizona (and) Incident occurred December 27, 2016 in Snowflake, Navajo County, Arizona

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

NTSB Identification: WPR17LA068
14 CFR Part 91: General Aviation
Accident occurred Saturday, February 18, 2017 in Holbrook, AZ
Probable Cause Approval Date: 05/25/2017
Aircraft: ROBINSON HELICOPTER R22 BETA, registration: N7095A
Injuries: 2 Uninjured.

NTSB investigators may not have traveled in support of this investigation and used data provided by various sources to prepare this aircraft accident report.

The private pilot was conducting a personal local flight in the helicopter. The pilot stated that he was flying at a low altitude over a cow pasture and descended to look at the cows. The helicopter was operating at 10 knots with a 7-knot headwind when the pilot initiated a 180° turn, which resulted in a tailwind condition and a subsequent uncommanded descent. The pilot took remedial actions, but the helicopter landed hard, and the main rotor blades severed the tailboom. The pilot stated that there were no mechanical anomalies with the helicopter that would have precluded normal operation. It is likely that the helicopter lost effective translational lift during the turn from a headwind to a tailwind condition and that the pilot failed to compensate for the loss of translational lift, which resulted in the uncontrolled descent. 

The National Transportation Safety Board determines the probable cause(s) of this accident as follows:
The pilot’s failure to compensate for a loss of effective translational lift while turning from an upwind to a downwind condition at a low altitude and low airspeed, which resulted in a loss of helicopter control.

On February 18, 2017, about 0800 mountain standard time, the pilot of a Robinson R22 Beta, N7095A, experienced a loss of helicopter control while maneuvering in a turn and landed hard in an open field near Holbrook, Arizona. The private pilot/owner operated the helicopter under the provisions of 14 Code of Federal Regulations Part 91, as a personal flight. The pilot and one passenger were not injured. The helicopter was substantially damaged. Visual meteorological conditions prevailed for the local area flight and no flight plan had been filed. The flight departed from a private residence about 0715 the morning of the accident.

According to the pilot's written statement, he departed from his brother's residence about 0715 with the intent of flying around Holbrook on a personal flight. They over flew a cow pasture, and descended to look at the cows. The pilot reported his airspeed was about 10 knots with a 7-knot headwind. He maneuvered the helicopter in a 180-degree turn and the helicopter started an un-commanded descent. He pulled cyclic control, which responded by lowering engine and main rotor blade rpm; he tried to lower and increase throttle, and flared to land; however, the helicopter landed hard. The main rotor blades contacted and subsequently severed the tail boom.

The pilot stated that there were no mechanical anomalies that would have precluded normal operation of the helicopter.

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

NTSB Identification: WPR17LA068 
14 CFR Part 91: General Aviation
Accident occurred Saturday, February 18, 2017 in Holbrook, AZ
Aircraft: ROBINSON HELICOPTER R22 BETA, registration: N7095A
Injuries: 2 Uninjured.

NTSB investigators may not have traveled in support of this investigation and used data provided by various sources to prepare this aircraft accident report.

On February 18, 2017, about 0800 mountain standard time, the pilot of a Robinson R22 Beta, N7095A, experienced a loss of helicopter control while maneuvering in a turn and landed hard in an open field near Holbrook, Arizona. The private pilot/owner operated the helicopter under the provisions of 14 Code of Federal Regulations Part 91, as a personal flight. The pilot and one passenger were not injured. The helicopter was substantially damaged. Visual meteorological conditions prevailed for the local area flight and no flight plan had been filed. The flight departed from a private residence about 0715 the morning of the accident.

According to the pilot's written statement, he departed from his brother's residence about 0715 with the intent of flying around Holbrook on a personal flight. They over flew a cow pasture, and descended to look at the cows. The pilot reported his airspeed was about 10 knots with a 7-knot headwind. He maneuvered the helicopter in a 180-degree turn and the helicopter started an un-commanded descent. He pulled cyclic control, which responded by lowering engine and main rotor blade rpm; he tried to lower and increase throttle, and flared to land; however, the helicopter landed hard. The main rotor blades contacted and subsequently severed the tail boom.

The pilot stated that there were no mechanical anomalies that would have precluded normal operation of the helicopter.

The National Transportation Safety Board did not travel to the scene of this accident. 

Additional Participating Entity:
Federal Aviation Administration / Flight Standards District Office: Scottsdale, Arizona 

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

http://registry.faa.gov/N7095A

NTSB Identification: WPR17LA068

14 CFR Part 91: General Aviation
Accident occurred Saturday, February 18, 2017 in Holbrook, AZ
Aircraft: ROBINSON HELICOPTER R22 BETA, registration: N7095A
Injuries: 2 Uninjured.

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 may not have traveled in support of this investigation and used data provided by various sources to prepare this aircraft accident report.

On February 18, 2017, about 0800 mountain standard time, a Robinson R22 Beta, N7095A, landed hard in an open field near Holbrook, Arizona, after the pilot experienced a loss of helicopter control while maneuvering. The private pilot/owner operated the helicopter as a 14 Code of Federal Regulations Part 91 personal flight. The pilot and one passenger were not injured. The helicopter was substantially damaged. Visual meteorological conditions prevailed for the local area flight and no flight plan had been filed. The flight departed from a private residence about 0715 the morning of the accident.

According to the pilot's written statement, he departed from his brothers residence about 0715 with the intent of flying around Holbrook on a personal flight. They overflew and descended over a cow pasture to look at the cows. The pilot reported his airspeed was about 10 knots with a 7 knot headwind. He maneuvered the helicopter in a 180-degree turn and the helicopter lost lift. He pulled cyclic, which responded by lowering engine and main rotor blade rpm; he tried to lower and increase throttle, and flared to land; however, the helicopter landed hard. The main rotor blades contacted and subsequently severed the tail boom.

The pilot stated that there were no mechanical problems that would have precluded normal operation of the helicopter.

While landing on a flatbed, the rotor struck the head of a person on the ground.

Date: 27-DEC-16
Time: 23:41:00Z
Regis#: N7095A
Aircraft Make: ROBINSON
Aircraft Model: R22
Event Type: INCIDENT
Highest Injury: MINOR
Aircraft Missing: No
Damage: NONE
Activity: UNKNOWN
Flight Phase: LANDING (LDG)
City: SNOWFLAKE
State: ARIZONA

Rotorcraft landed in a pasture and was powering down when the ground crew was to refuel the rotorcraft was struck in the back of the head by a rotor blade, requiring transport to a hospital and at least two (2) stitches.   

Date: 27-DEC-16
Time: 23:41:00Z
Regis#: N709FA
Aircraft Make: ROBINSON
Aircraft Model: R22
Event Type: INCIDENT
Highest Injury: MINOR
Aircraft Missing: No
Damage: UNKNOWN
Activity: PERSONAL
Flight Phase: STANDING (STD)
Operation: 91
City: SNOWFLAKE
State: ARIZONA

Air Tractor AT-602, N602L: Accident occurred December 27, 2016 at Willows-Glenn County Airport (KWLW), California

The National Transportation Safety Board did not travel to the scene of this accident.

Additional Participating Entities:
Federal Aviation Administration / Flight Standards District Office; Sacramento, California
Air Tractor, Inc.; Olney, Texas
Pratt and Whitney Canada; Montreal

Analysis 

The commercial pilot of the turboprop-equipped airplane departed from the maintenance facility airport following the completion of a 100-hour inspection, which included a compressor bleed valve overhaul. He did not perform an engine run-up or a post maintenance performance check as recommended by the engine manufacturer but noticed that the engine was "sluggish" during takeoff. Near the conclusion of the 25-minute flight, the pilot initiated a straight-in approach to his destination airport and slightly reduced engine power. Immediately, he heard a "pop" noise and observed a reduction in airspeed. When the pilot advanced the throttle to full power, the engine power and airspeed did not change, and the airplane began to sink. The pilot conducted an off-airport forced landing and the airplane nosed over and came to rest inverted.

Postaccident examination of the engine revealed that the valve seat had not been installed on the overhauled compressor bleed valve. The maintenance manual overhaul procedure requires that the bleed valve seat remain with the engine, which requires that the seat be removed from the old core unit and installed on the replacement or overhauled bleed valve before installing that component on the engine. At the time of the inspection, the inspection facility's director of maintenance encountered trouble retrieving the maintenance manual for this model engine from the manufacturer's website and decided to continue the service under the assumption that the bleed valve replacement was similar to another engine model with which he was familiar. The inspection facility submitted the core unit without removing the bleed valve seat, and the valve overhaul facility did not install any seat on the overhauled bleed valve, which was in compliance with the overhaul procedure. The inspection facility then installed the overhauled unit on the engine without the necessary valve seat. Additionally, the inspection facility failed to complete the bleed valve closing check procedure required by the engine manufacturer, which likely would have revealed a malfunctioning bleed valve. Further, the inspection facility reported that they performed an engine run up after completing maintenance, but contrary to required procedures did not record any power settings. Without the power setting data, the investigation was unable to positively determine whether the bleed valve closed properly during the ground test. Additionally, neither the maintenance facility nor the pilot completed the engine manufacturer's recommended engine performance check after the service was completed.

The airplane was sluggish during takeoff because the engine was not able to achieve full power due to the absence of the bleed valve seat and consequent malfunctioning of the bleed valve. The "pop" sound heard by the pilot when he attempted to increase power during his approach was likely a compressor stall caused by the malfunctioning bleed valve. The malfunctioning bleed valve would have prevented the engine from responding to any additional power demand at this critical moment, and once the engine failed to respond, the pilot likely determined that the airplane would not reach the runway and completed a forced off-airport landing.

Probable Cause and Findings

The National Transportation Safety Board determines the probable cause(s) of this accident to be: 
The decision of the maintenance facility mechanic to conduct maintenance without reference to the applicable manufacturer's guidance, which resulted in the improper reassembly and subsequent failure of the engine compressor bleed valve, which in turn prevented the engine from responding to further power demand at a critical phase of flight. Contributing to the accident was the failure of the maintenance facility's director of maintenance to ensure that the overhaul was conducted properly and that the required post-maintenance test procedures were accomplished. 

Findings

Aircraft
Compressor bleed valve - Incorrect service/maintenance (Cause)

Personnel issues
Decision making/judgment - Maintenance personnel (Cause)
Installation - Maintenance personnel (Cause)

Factual Information

History of Flight

Approach-VFR pattern final
Powerplant sys/comp malf/fail
Loss of engine power (partial) (Defining event)

Emergency descent
Off-field or emergency landing

Landing-flare/touchdown

Nose over/nose down

Location: Willows, CA
Accident Number: WPR17LA042
Date & Time: 12/27/2016, 1553 PST
Registration: N602L
Aircraft: AIR TRACTOR INC AT 602
Aircraft Damage: Substantial
Defining Event: Loss of engine power (partial)
Injuries: 1 None
Flight Conducted Under:  Part 91: General Aviation - Positioning 

On December 27, 2016, about 1553 Pacific standard time, an Air Tractor AT-602, N602L, was substantially damaged when the airplane landed short at Willows-Glenn County Airport (WLW), Willows, California. The commercial pilot was not injured. The airplane was owned and operated by the pilot under the provisions of Title 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed and no flight plan was filed for the cross-country flight that departed Medlock Field Airport (69CL), Davis, California at approximately 1527. The personal flight was destined for WLW. 

According to the pilot, he was returning the airplane to WLW after a recent 100-hour inspection with 160 gallons of JET A fuel onboard. The airplane seemed sluggish during takeoff and the engine did not produce more than 97% power, but the pilot did not observe an exceedance of the engine's turbine inlet temperature or any further abnormal instrument indications. At the conclusion of the 25-minute flight, the pilot initiated a straight-in approach to runway 31 and slightly reduced the throttle. Immediately, he heard a "pop" noise, and observed a reduction in airspeed. When the pilot advanced the throttle to full power the engine power and airspeed did not change, and the airplane began to sink rapidly. Further attempts at recycling the throttle were unsuccessful in restoring engine power. As the airplane approached the south end of the airport, the pilot deployed the wing flaps, and the main landing gear touched down on a gravel road beyond a ditch. The tailwheel impacted the ditch and bounced, and the airplane nosed over and came to rest inverted. 

The pilot later reported that he did not complete an engine run-up or power assurance check before the accident flight, which is not a required item by the airplane manufacturer. The pilot also reported that the "pop" sound may have been from a hunting party that was in the area at the time of the accident.

Postaccident examination by a Federal Aviation Administration (FAA) inspector revealed substantial damage to the rudder and left wing spar. Additionally the inspector reported an unknown quantity of fuel in the left main fuel tank. The fuel and fuel filter did not appear to be contaminated, and the fuel lines and fuel strainer did not appear to be obstructed.

Pilot Information

Certificate: Commercial
Age: 30, Male
Airplane Rating(s): Single-engine Land
Seat Occupied: Single
Other Aircraft Rating(s): Helicopter
Restraint Used: 5-point
Instrument Rating(s): None
Second Pilot Present: No
Instructor Rating(s): None
Toxicology Performed: No
Medical Certification: Class 2 Without Waivers/Limitations
Last FAA Medical Exam: 02/22/2016
Occupational Pilot: Yes
Last Flight Review or Equivalent: 02/01/2016
Flight Time:  4147 hours (Total, all aircraft), 2085 hours (Total, this make and model), 4055 hours (Pilot In Command, all aircraft), 35 hours (Last 90 days, all aircraft), 16 hours (Last 30 days, all aircraft), 0 hours (Last 24 hours, all aircraft) 

Aircraft and Owner/Operator Information


Aircraft Make: AIR TRACTOR INC
Registration: N602L
Model/Series: AT 602 NO SERIES
Aircraft Category: Airplane
Year of Manufacture: 1999
Amateur Built: No
Airworthiness Certificate: Restricted; Utility
Serial Number: 602-0526
Landing Gear Type: Tailwheel
Seats: 1
Date/Type of Last Inspection: 12/26/2016, Annual
Certified Max Gross Wt.:
Time Since Last Inspection: 0 Hours
Engines: Turbo Prop
Airframe Total Time: 6537 Hours at time of accident
Engine Manufacturer: Pratt & Whitney
ELT: Not installed
Engine Model/Series: PT6A-65ag
Registered Owner: On file
Rated Power: 1300 hp
Operator: On file
Operating Certificate(s) Held: Agricultural Aircraft (137) 

According to FAA records, the airplane was manufactured in 1999, and registered to the pilot's family in 2010. The airplane was powered by a Pratt and Whitney PT6A-65AG, 1,300 shaft horsepower turboprop engine. The aircraft logbooks showed that the airplane's most recent 100 hour inspection was completed on December 22, 2016 at which time the airframe had accumulated 6,537 total flight hours and the engine had accumulated 4,974.5 total flight hours. The airplane accumulated 0.4 hours between that inspection and the accident. The engine's previous hot section inspection was completed on May 1, 2014 at a total time of 4,078 flight hours. 

Meteorological Information and Flight Plan

Conditions at Accident Site: Visual Conditions
Condition of Light: Day
Observation Facility, Elevation: OVE, 194 ft msl
Distance from Accident Site: 27 Nautical Miles
Observation Time: 1553 PST
Direction from Accident Site: 90°
Lowest Cloud Condition: Clear
Visibility:  10 Miles
Lowest Ceiling: None
Visibility (RVR):
Wind Speed/Gusts: Calm /
Turbulence Type Forecast/Actual: / None
Wind Direction:
Turbulence Severity Forecast/Actual: / N/A
Altimeter Setting: 30.32 inches Hg
Temperature/Dew Point: 11°C / 1°C
Precipitation and Obscuration: No Obscuration; No Precipitation
Departure Point: DAVIS, CA (69CL)
Type of Flight Plan Filed: None
Destination: WILLOWS, CA (WLW)
Type of Clearance: None
Departure Time: 1527 PST
Type of Airspace: Class G 

Airport Information

Airport: WILLOWS-GLENN COUNTY (WLW)
Runway Surface Type: Asphalt
Airport Elevation: 141 ft
Runway Surface Condition: Unknown
Runway Used: 31
IFR Approach: None
Runway Length/Width: 3788 ft / 60 ft
VFR Approach/Landing: Straight-in

Wreckage and Impact Information

Crew Injuries: 1 None
Aircraft Damage: Substantial
Passenger Injuries: N/A
Aircraft Fire: None
Ground Injuries: N/A
Aircraft Explosion: None
Total Injuries: 1 None
Latitude, Longitude: 39.509444, -122.216944 (est) 

Tests And Research

An initial examination of the airplane was completed under the supervision of the NTSB Investigator-in-Charge by a representative of Pratt and Whitney Canada who was an airframe and powerplant mechanic. The oil filter, fuel filter, and filter to the high pressure fuel pump were inspected. The oil filter displayed some carbon debris, while both the fuel filter and filter to the fuel pump were free of contamination. A clear liquid was observed in the fuel bowl that exhibited an odor and appearance that resembled JET A fuel.

Compressor Bleed Valve

The purpose of the compressor bleed valve is to prevent a compressor stall at low gas generator speeds. The unit is comprised of a piston that is pushed into the closed position by P3 air and moved to the open position using P2.5 air from the inter-stage compressor area. At low power settings, P3 pressure is lower than the P2.5 pressure, which causes the bleed valve to position itself to the open condition. As compressor speed increases, P3 pressure rises faster than the P2.5 pressure, which causes the bleed valve to move towards the closed condition.

The speed at which the valve closes is both a function of P3 pressure and surface area on which P2.5 pressure is pushing on the piston. P3 pressure is dependent on the restriction at the outlet of the cavity where it is drawn. The surface area on which P2.5 air pushes depends on the inside diameter of the bleed valve seat.

According to the engine manufacturer, the piston will normally extend to the closed position against the valve seat in response to a power demand from the operator. The piston is equipped with a carbon ring that is normally compressed between the piston and the piston guide collar. If the valve seat is not installed, the piston can travel beyond its normal range, which allows the carbon ring to expand and come out of its groove. This will then prevent the valve piston from moving within its guide collar. The absence of the valve seat will cause a permanent air leak around the piston, which will allow P2.5 pressure to escape the engine. This condition can prevent the engine from accommodating any additional power demand and/or result in significantly slower accelerations.

At the time of the accident airplane's recent 100 hour inspection, the bleed valve was replaced with an overhauled unit from the bleed valve overhaul facility, Prime Turbines. The original bleed valve had been submitted to Prime Turbines a few weeks earlier as a core unit.

During the post accident examination, when the bleed valve was removed from the engine, its internal piston fell out, indicating that it was not secured within the valve body, as it was supposed to have been. An inspection of the bleed valve showed that the valve filter was intact and free of contamination. A comparison of the accident bleed valve with the manufacturer's illustrated parts catalogue revealed that the valve seat was absent and the two screws that normally secure the seat to the valve body were installed finger tight and protruded from the flange of the valve body, preventing proper seating when the valve was installed on the engine. In response to a query by the investigation, a representative of bleed valve overhaul facility discovered the valve seat among the components that comprised the previously submitted core unit.

According to the section of the engine maintenance manual entitled "Compressor Bleed Valve – Maintenance Practices," the bleed valve seat must be removed from the core unit and remain with the gas generator assembly after the bleed valve has been removed. Once the overhauled bleed valve arrives, the previously retained seat should be installed on the replacement bleed valve and tightened to 5 to 6 inch lbs before the unit is installed on the engine.

Maintenance Facility

The Director of Maintenance (DOM) to Grower's Air Service, the service facility, who also signed off the airplane's most recent 100 hour inspection, reported that his facility started working on PT6A-65AG engines about 2 years ago. During this time period, the company only serviced 2 PT6A-65AG model engines, including the engine from the accident airplane. Initially, the DOM stated that they completed the engine inspection in accordance with the manufacturer's maintenance manual (MM), which was revised in March 2016. Normally, the maintenance facility DOM will review the applicable service manuals prior to engaging in a particular maintenance activity. However, the DOM had trouble accessing the manuals through the manufacturer's website, and decided not to review the bleed valve guidance prior to the maintenance on the accident engine because he assumed that the procedures were similar to those prescribed for the PT6A-34A and PT6A-60 engines, which the facility regularly services. According to a PT6A-34A diagram, the bleed air valve is not equipped with a calibrated seat similar to the bleed valve assembly on the PT6A-65AG engine as it contains a metering orifice in the P3 air inlet.

The DOM stated that he removed the old bleed valve from the engine, and that another mechanic installed the overhauled unit. When asked about the valve seat by the investigative team, the DOM stated that he was not aware that the bleed valve on the PT6A-65AG had a removable valve seat, and was certain that the mechanic who installed the overhauled bleed valve on the engine was not aware of that removable valve seat either.

At the conclusion of the inspection, the line mechanic completed two engine runs to dynamically balance the propeller; however, the run-up power settings were not recorded by the maintenance facility. According to the maintenance manual, a bleed valve closing check procedure is required after the unit is installed to verify the gas generator speed at which the valve closes. This value is charted using the gas generator speed and plenum pressure. This procedure was not completed by the maintenance facility.

The engine maintenance manual includes guidance for completing an engine performance check to measure engine torque, fuel flow, gas generator and gas generator speed at various temperatures and specified power settings. This check is only recommended by the engine manufacturer at regular intervals and after major service. The maintenance facility did not conduct an engine performance check following the service that included the bleed valve replacement.

Engine and Component Examinations

A subsequent examination of the engine was completed at the engine manufacturer's facility under the supervision of the NTSB. The accessory gearbox section gears and shafts rotated freely when actuated by hand. The compressor was not displaced and did not exhibit any impact damage signatures. The N1 rotated freely through the tach generator. A small corner piece to one of the 2nd stage compressor blades had separated and several 3rd and 4th stage compressor blades exhibited trailing edge damage. The prop flange, reduction gearbox, and power turbine blades rotated freely when actuated by hand at the main drive shaft. The turbine blades and stator vanes did not display any abnormal wear. Some rotational scoring was observed along the power turbine shroud, but the turbine blades did not display any visible damage. The left side exhaust case was damaged.

All 14 fuel nozzles tested within normal limits with the exception of the nozzles at position nos. 5, 9, 10, and 12. The spray angles produced by fuel nozzle No. 5 were uneven and a subsequent microscope inspection revealed the presence of varnish along the circumference of the tip. Fuel nozzle no. 9 displayed a small leak during the pressure test, a pencil streakiness was observed from nozzle no. 10 and the flow rate of nozzle no. 12 was below the minimum specification. Further, the tab washer tangs to nozzle nos. 2, 3 and 10 were wider than the manufacturer's production part. The flow divider tested normally and produced results within the manufacturer's limitations. According to the manufacturer, the condition of the fuel nozzles would not have had an influence on the engine's ability to make power.

The fuel control unit (FCU) low and high idle fuel flow values were above the manufacturer's limitations. However, those limits are the manufacturer's pre-delivery/production values, and the manufacturer assumes that the operator will make some adjustments to FCU flow values in service. Additionally, the recorded results for power lever speed (rpm) were higher than manufacturer limitations, which is also a factory requirement. This indicates that the operator and/or the maintenance facility adjusted the low idle, high idle, and max forward and reverse compressor speed positions.

The FCU was run on a test stand at a simulated cruise power setting, with a fixed speed, fixed P3, and power lever angle. The unit was allowed to run for 16 minutes and did not yield any change in the fuel flow, consistent with normal operation. Fuel flow values were normal when the unit was operated at lower RPM speeds, but exceeded the limits by a few pounds per hour at simulated cruise speeds. The FCU was then adjusted to meet production standards. A subsequent test revealed that the FCU produced similar results to its pre-calibration settings.

The fuel pump was placed on a test stand and a pump calibration test was conducted, which tested for leakage at various shaft speeds; the results were within the acceptable range. A subsequent seal drain leakage test was performed with the discharge valve closed. An inlet pressure of 50 psig was selected and maintained for about 5 minutes and no leaks were observed. The filter bypass valve pressure drop was computed by subtracting the discharge pressure from the filter inlet pressure and the results were within the manufacturer's prescribed limitations.

The fuel to oil heat exchanger was tested for core matrix internal leakage and to test the travel of the unit's thermal element. No leaks were observed in the exchanger and the thermal element showed wear. A full description of the fuel to oil heat exchanger test is included as a record of conversation with the engine manufacturer in the NTSB public docket.

Engine Surge

According to the engine manufacturer, a "pop" sound is characteristic of an engine surge. As designed, the compressor assembly draws in too much air at low speeds, which can lead to a compressor stall. The compressor bleed valve opens at low speeds to bleed this excess air and prevent the stall. If the bleed valve setting is improper, the valve will not close correctly and an engine surge can occur, which can lead to a compressor stall. As discussed above, the missing bleed valve seat would result in improper bleed valve function, which in turn could result in compressor stalls.
  
NTSB Identification: WPR17LA042
14 CFR Part 91: General Aviation
Accident occurred Tuesday, December 27, 2016 in Willows, CA
Aircraft: AIR TRACTOR INC AT 602, registration: N602L
Injuries: 1 Uninjured.

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 may not have traveled in support of this investigation and used data provided by various sources to prepare this aircraft accident report.

On December 27, 2016, about 1553 Pacific standard time, an Air Tractor AT-602, N602L, was substantially damaged during a forced landing at Willows-Glenn County Airport (WLW), Willows, California. The commercial pilot was not injured. The airplane was owned and operated by the pilot under the provisions of Title 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed and no flight plan was filed for the cross-country flight that departed Medlock Field Airport (69CL), Davis, California at approximately 1527. The personal flight was destined for WLW. 

According to the pilot, he was returning the airplane to his home airport after a recent annual inspection. At the conclusion of the 25 minute flight, the pilot initiated a straight-in approach to runway 31 and slightly reduced the throttle. Immediately, he heard a "pop" noise, and observed a reduction in airspeed. When the pilot advanced the throttle to full power the engine power and airspeed did not change and the airplane began to sink rapidly. Further attempts to recycle the throttle were unsuccessful. As the airplane approached a canal on the south end of the airport, the pilot deployed the wing flaps and the main landing gear touched down on a gravel road beyond a ditch. The tailwheel impacted the ditch and the airplane flipped over and came to rest inverted. 

Postaccident examination by a Federal Aviation Administration inspector revealed substantial damage to the rudder and left wing spar. 

The wreckage was retained for further examination.