Sunday, April 19, 2020

Powerplant System/Component Malfunction/Failure: Zenith STOL CH750, N328SK; accident occurred August 11, 2018 near Napa County Airport (KAPC), California




















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

Additional Participating Entity:

Federal Aviation Administration / Flight Standards District Office; Sacramento, California

Aviation Accident Factual 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/N328SK

Location: Napa, CA
Accident Number: WPR18TA223
Date & Time: 08/11/2018, 1056 PDT
Registration: N328SK
Aircraft: Zenair ZENITH STOL CH750
Aircraft Damage:Substantial 
Defining Event: Powerplant sys/comp malf/fail
Injuries: 2 None
Flight Conducted Under: Part 91: General Aviation - Personal 

On August 11, 2018, about 1056 Pacific daylight time, an experimental, amateur-built Zenith CH-750 airplane, N328SK, was substantially damaged during a forced landing near Napa County Airport (APC), Napa, California. The commercial pilot/owner and his pilot-rated passenger were not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. Visual meteorological conditions existed at APC about the time of the accident. The local flight had originated from APC about 25 minutes earlier.

According to the pilot, who was also the builder of the airplane, the airplane was for sale, and the accident flight was a demonstration/familiarization flight for a potential buyer. The pilot reported that they flew in the local area for about 20 minutes, and then he handed airplane control to the potential buyer, who was in the right seat. The buyer wanted to see how slowly the airplane could fly, and decelerated to about 30 knots, which resulted in a significant airplane-nose-up pitch attitude. The airplane began "sinking," so the pilot/owner took back control and pushed the nose over to regain airspeed. Almost immediately smoke entered the cockpit. The pilot declared an emergency and headed towards APC. Within a minute or two, the engine lost all oil pressure, and then ceased developing power.

The pilot initially attempted to glide to the airport, but then realized that the airport was too distant. He then decided to land on a road atop a nearby levee. The airplane touched down on the road, and the initial rollout was satisfactory. However, due to wind, the left wingtip struck the ground, and spun the airplane around. Due to the narrow width of the road and levee, the airplane then veered off the levee, and damaged the wing and fuselage. The airplane came to rest below the top of the levee, about 0.6 miles west of the APC runway 6 threshold.

According to Federal Aviation Administration (FAA) information, about 1050 the pilot reported to the APC air traffic control tower (ATCT) local controller (LC) that he had an "oil pressure issue." The LC asked the pilot if he required any assistance, and the pilot replied in the negative. At 1055 the pilot re-contacted the LC, advising that he was having "more issues," but did not elaborate. The ATCT controller in charge (CiC) declared an emergency for the pilot. The pilot then radioed that he had lost all engine power and was attempting to reach runway 6. At 1056 the pilot advised the LC that he could not make the runway and was landing on a levee about 1/2 mile short of the runway. After the airplane came to rest, the pilot notified the LC of their situation.

Pilot Information

Certificate: Commercial
Age: 67, Male
Airplane Rating(s): Single-engine Land
Seat Occupied: Left
Other Aircraft Rating(s): Helicopter
Restraint Used:
Instrument Rating(s): Airplane
Second Pilot Present: Yes
Instructor Rating(s): None
Toxicology Performed: No
Medical Certification: BasicMed
Last FAA Medical Exam: 04/03/2017
Occupational Pilot: No
Last Flight Review or Equivalent: 09/21/2017
Flight Time:  7700 hours (Total, all aircraft), 200 hours (Total, this make and model), 7500 hours (Pilot In Command, all aircraft), 15 hours (Last 90 days, all aircraft), 5 hours (Last 30 days, all aircraft) 

FAA records indicated that the pilot held a commercial pilot certificate with airplane single-engine land, rotorcraft-helicopter, and instrument airplane ratings. He also held a repairman experimental aircraft builder certificate valid for the accident airplane. According to information provided by the pilot, he had approximately 7,700 total hours of flight experience, including about 200 hours in the accident airplane make and model. His most recent flight review was completed in September 2017, and his most recent medical certificate was issued under the Basic Med program in April 2017.

Aircraft and Owner/Operator Information

Aircraft Make: Zenair
Registration:N328SK 
Model/Series: ZENITH STOL CH750 No Series
Aircraft Category: Airplane
Year of Manufacture:2014 
Amateur Built: Yes
Airworthiness Certificate: Experimental
Serial Number: 75-8975
Landing Gear Type: Tricycle
Seats: 2
Date/Type of Last Inspection: 04/01/2017, 100 Hour
Certified Max Gross Wt.:
Time Since Last Inspection:
Engines: 1 Reciprocating
Airframe Total Time: 200 Hours as of last inspection
Engine Manufacturer: ULPower
ELT: Installed, not activated
Engine Model/Series: 350iS
Registered Owner: On file
Rated Power: 130 hp
Operator: On file
Operating Certificate(s) Held: None

General

FAA records indicated that the airplane was built by the pilot, and received its initial airworthiness approval in 2014. The airplane was equipped with a Belgian ULPower brand 350iS series piston engine that was rated at 130 horsepower.

Engine Fuel

The ULPower Operating Manual (OM) for the engine stated that "regular unleaded automotive fuel…should be used to operate" the engine. The OM specified minimum octane rating values of 98 RON, 90 MON, or 94 AKI. "RON" and "MON" are two different methods and indices for determining the octane value. "AKI" stands for anti-knock index, and is the arithmetic mean of RON and MON. In the United States, the octane ratings posted by automotive fuel vendors are AKI values. Predominant US AKI values range from 87 to 93. A ULPower representative stated that the 93 AKI fuel in the US is acceptable for use in the engine. Finally, the OM also stated that "AVGAS 100 LL and/ or AVGAS UL91 may be used if regular fuel is not available." The pilot did not specifically report the fuel(s), or the octane rating(s) of those fuel(s), that he used in the engine.

Logbook Information

The pilot-provided maintenance records were neither current nor in compliance with applicable FAA regulations. The records lacked the FAA-required documentation that certified the completion of the FAA-required Phase 1 flight test period. The airframe log only contained a single entry, dated 2014, which appeared to be the original post-build airworthiness signoff for the airplane. Although the pilot reported that he had an engine logbook, he did not provide one to the investigation. The records that were provided by the pilot did not include any entries that documented any maintenance activities.

Maintenance Information

According to pilot-provided information, the most recent "100 hour" inspection was completed on April 1, 2017, and that at that time both the airplane and engine total time in service was 200.5 hours. The pilot reported to an FAA inspector that he had previously had "low compression problems" with the engine, and that he had sent the engine back to the manufacturer for replacement of several components, including all four cylinder heads, one cylinder, and all piston rings. The pilot did not provide any documentation or other substantiation of that assertion. The incomplete maintenance records precluded evaluation of the maintenance history of the engine.

Engine Oil Changes

Regular oil changes that include examination of the oil filter and oil sample analyses are common practices that are proven to provide early detection of unusual engine wear or deterioration. The pilot-provided records did not include any entries that documented any oil changes, oil filter examinations, or oil sample analyses.

Pilot's Accident Accounts

In his initial communications with the NTSB about the accident, the pilot reported that he believed that the high pitch attitude during the demonstration flight had caused the oil to be vented overboard via the oil breather assembly. In his subsequent written accident report to the NTSB, the pilot reported that "something broke in the engine and dumped oil into the muffler from the no.1 exhaust."

Meteorological Information and Flight Plan

Conditions at Accident Site: Visual Conditions
Condition of Light: Day
Observation Facility, Elevation: APC, 36 ft msl
Distance from Accident Site: 1 Nautical Miles
Observation Time: 1054 PDT
Direction from Accident Site: 90°
Lowest Cloud Condition: Clear
Visibility:  10 Miles
Lowest Ceiling: None
Visibility (RVR):
Wind Speed/Gusts: 11 knots /
Turbulence Type Forecast/Actual:
Wind Direction: 220°
Turbulence Severity Forecast/Actual:
Altimeter Setting: 29.98 inches Hg
Temperature/Dew Point: 23°C / 14°C
Precipitation and Obscuration: Freezing - No Obscuration; No Precipitation
Departure Point: Napa, CA (APC)
Type of Flight Plan Filed: None
Destination: Napa, CA (APC)
Type of Clearance: VFR
Departure Time: 1030 PDT
Type of Airspace: Class D

The 1054 APC automated weather observation included winds from 220° at 11 knots, visibility 10 miles, clear skies, temperature 23°C, dew point 14°C, and an altimeter setting of 29.98 inches of mercury.

Airport Information

Airport: Napa County (APC)
Runway Surface Type: Dirt; Grass/turf; Gravel
Airport Elevation: 36 ft
Runway Surface Condition: Dry; Rough
Runway Used: N/A
IFR Approach: None
Runway Length/Width:
VFR Approach/Landing: Forced Landing

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: 38.200000, -122.291667 (est) 

Examination of the airplane by an FAA inspector revealed that the wings and fuselage had sustained crush or buckling damage from the impact. The engine exhibited some impact-related damage, but it did not exhibit any visual evidence of any external non-impact related damage. The engine was found to be devoid of lubricating oil. Significant oil residue was observed on the muffler, and all along the lower fuselage. The source of the oil appeared to be in the region of the starter ring gear and its drive penetration of the engine case. The muffler was situated below the ring gear drive case penetration.

The hour meter registered a total time of 200.8 hours.

The engine was removed and shipped to the manufacturer's service facility in the US, where it was disassembled and examined in detail. All four pistons displayed evidence of significant erosion damage, consistent with detonation. At least one piston was eroded to the point that it could no longer seal against the cylinder wall. The engine manufacturer's representative attributed this level of damage to the use of 87 octane (AKI) fuel.

This piston damage would allow cylinder combustion gasses to enter and pressurize the engine crankcase, which in turn could force oil past any flexible seals and out of the crankcase. Specifically, pressurization of the crankcase could also force oil past the starter ring gear seal, out of the engine.

The engine control unit (ECU) was removed and shipped to the engine manufacturer's facility in Belgium. The ECU internal programming was validated, and then the ECU was installed on a testbed engine. That engine operated normally with the accident ECU installed.

Separately, and contrary to the pilot's unsubstantiated assertions that he had previously sent the engine back to the manufacturer for "low compression" problems, the manufacturer's records indicated no such event. Despite the fact that the engine was no longer under warranty, the engine manufacturer did provide the pilot with some replacement components at no charge. In addition, the sole US-based engine manufacturer's service center indicated that there were no records of that service center conducting any repair actions on that engine.

Additional Information

Detonation

Chapter 7 of the FAA publication Pilot's Handbook of Aeronautical Knowledge (PHAK) presented the following information regarding detonation:

Detonation is an uncontrolled, explosive ignition of the fuel-air mixture within the cylinder's combustion chamber. It causes excessive temperatures and pressures which, if not corrected, can quickly lead to failure of the piston, cylinder, or valves. In less severe cases, detonation causes engine overheating, roughness, or loss of power.

Detonation is characterized by high cylinder head temperatures and is most likely to occur when operating at high power settings. Common operational causes of detonation are:
- Use of a lower fuel grade than that specified by the aircraft manufacturer
- Operation of the engine with extremely high manifold pressures in conjunction with low rpm
- Operation of the engine at high power settings with an excessively lean mixture
- Maintaining extended ground operations or steep climbs in which cylinder cooling is reduced

Detonation may be avoided by following these basic guidelines during the various phases of ground and flight operations:
- Ensure that the proper grade of fuel is used.
- Use an enriched fuel mixture, as well as a shallow climb angle, to increase cylinder cooling during takeoff and initial climb.
- Avoid extended, high power, steep climbs.
- Develop the habit of monitoring the engine instruments to verify proper operation according to procedures established by the manufacturer.

System/Component Malfunction/Failure (Non-Power): Cessna T337G, N255; accident occurred August 08, 2018 at Lewiston-Nez Perce County Regional Airport (KLWS), Idaho









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

Additional Participating Entities: 

Federal Aviation Administration / Flight Standards District Office; Helena, Montana
Textron Aviation; Wichita, Kansas

Aviation Accident Factual 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/N255

Location: Lewiston, ID
Accident Number: WPR18LA215
Date & Time: 08/08/2018, 1828 PDT
Registration: N255
Aircraft: Cessna T337
Aircraft Damage: Substantial
Defining Event: Sys/Comp malf/fail (non-power)
Injuries: 2 None
Flight Conducted Under: Part 91: General Aviation - Aerial Observation

On August 8, 2018, about 1828 Pacific daylight time, a Cessna T337G airplane, N255, was substantially damaged to the lower fuselage during landing at Lewiston Perce Nez Airport (LWS) Lewiston, Idaho. The commercial pilot and his passenger were not injured. The airplane was registered to Northern Air Inc, and was under contract to and being operated by the United States Forest Service as a Title 14 Code of Federal Regulations Part 91 aerial survey flight. Visual meteorological conditions existed at the time of the accident and no flight plan was filed. The flight had originated from LWS about 5 hours before the accident.

According to the pilot, the airplane operated normally for the mission, and for most of the landing approach. However, when the pilot selected the landing gear to the extended position, the gear doors opened, the electric motor that pressurized the hydraulic extension system continued to run, but the landing gear failed to extend. The pilot reported that the airplane was at a speed about 20 mph below the maximum landing gear operating speed when he selected the gear down. The pilot pulled the circuit breaker for the pump motor and abandoned the approach. He then flew a short distance away from LWS so that he could attempt to troubleshoot and rectify the problem.

The pilot cycled the landing gear control five or six times, but all efforts to operate the landing gear were unsuccessful. He then employed his passenger to assist him with running the checklists and other troubleshooting activities. The pilot and passenger determined that the landing gear system hydraulic fluid reservoir that was accessible to them in the cabin was empty. The pilot contacted his maintenance personnel by radio, and they assisted in additional attempts to correct the situation; these attempts included replenishing the reservoir with oil and water. Despite those efforts, the landing gear could not be successfully extended. The pilot decided to burn off extra fuel before returning to conduct a gear-up landing.

During the return approach, the pilot secured the front engine, and "bumped" the propeller with the starter to position the blades horizontally, in order to prevent damaging them by runway contact. The occupants unlatched a cabin door in order to enable assured opening after landing. The pilot landed the airplane gear up on runway 30, and the airplane slid to a stop within a few feet of the runway centerline.

Pilot Information

Certificate: Commercial
Age: 33, Male
Airplane Rating(s): Multi-engine Land; Single-engine Land; Single-engine Sea
Seat Occupied: Left
Other Aircraft Rating(s): None
Restraint Used:
Instrument Rating(s): Airplane
Second Pilot Present: No
Instructor Rating(s): None
Toxicology Performed: No
Medical Certification: Class 2 Without Waivers/Limitations
Last FAA Medical Exam: 05/09/2018
Occupational Pilot: Yes
Last Flight Review or Equivalent: 05/23/2018
Flight Time:   4460 hours (Total, all aircraft), 632 hours (Total, this make and model), 3445 hours (Pilot In Command, all aircraft), 82 hours (Last 90 days, all aircraft), 82 hours (Last 30 days, all aircraft), 6 hours (Last 24 hours, all aircraft) 

Federal Aviation Administration (FAA) records indicated that the pilot held a commercial pilot certificate with a airplane single engine, multiengine, and instrument ratings. According to information provided by the pilot, he had approximately 4,460 total hours of flight experience, including approximately 632 hours in the accident airplane make and model. His most recent flight review was completed in May 2018, and his most recent FAA second-class medical certificate was issued in May 2018.

Aircraft and Owner/Operator Information

Aircraft Make: Cessna
Registration: N255
Model/Series: T337 G
Aircraft Category: Airplane
Year of Manufacture: 1975
Amateur Built: No
Airworthiness Certificate: Normal
Serial Number: P3370213
Landing Gear Type: Retractable - Tricycle
Seats: 4
Date/Type of Last Inspection: 07/09/2018, Annual
Certified Max Gross Wt.: 4700 lbs
Time Since Last Inspection: 93 Hours
Engines: 2 Reciprocating
Airframe Total Time: 2848 Hours at time of accident
Engine Manufacturer: Continental Motors
ELT: C126 installed, not activated
Engine Model/Series: TSIO-360C
Registered Owner: Northern Air Inc
Rated Power: 225 hp
Operator: Northern Air Inc
Operating Certificate(s) Held: None 

The airplane was manufactured in 1975, as serial number P3370213. Operator information indicated that the airplane was equipped with two Continental Motors TSIO-360 series engines. The airplane was a centerline thrust configuration, and was equipped with retractable, tricycle-configuration landing gear. The airframe and both engines had each accumulated a total time (TT) in service of about 2,848 hrs. The engines had each accumulated about 880 hours TT since the most recent overhaul. The most recent annual inspection was completed on July 9, 2018.

The airplane manufacturer's published normal operating speed range for the airplane was 80 to 190 mph, and the caution speed range was from 190 to 230 mph. The maximum landing gear extension speed was 160 mph, and the maximum landing gear extended operating speed was 230 mph.

The landing gear was arranged in a tricycle configuration. All 3 landing gear retracted into the fuselage, and were aerodynamically faired by multiple doors for each wheel well. The aftmost and largest door for each of the two main landing gear wells extended from the fuselage bottom and partially up its respective fuselage side, resulting in an "L"- or bowl-like shape for the door. Due to their shape, these main landing gear doors are sometimes referred to as the "parachute" or "clamshell" doors.

Each main door was opened and closed by a dedicated hydraulic actuator attached to the door and the fuselage. Each actuator was equipped with an internal snap ring (sometimes referred to as a "circlip") that nested in a groove inside the actuator cylinder, functioned as a travel-limiting and retaining stop for the actuator rod in the actuator cylinder.

Each main door was hinged longitudinally along its upper (outboard) edge. The forward and aft door edges were oriented parallel to the airplane lateral axis. The inboard door edges were closest to the airplane centerline. During the landing gear extension cycle, each main door would swing down and then outboard, with a maximum travel of about 90°. When the doors were in transit or fully open, their shape and operating configuration resulted in significant airloads on the doors, and resultant aerodynamic drag on the airplane. These doors return to the closed position when the landing gear extension cycle is complete.

The airplane manufacturer's maintenance manual (MM) specified that after disassembly, the landing gear door actuator should be inspected for "cracks, chips, scoring, wear or surface irregularities which might affect…the overall function of the actuator." In the MM section for actuator re-assembly, the guidance specified to "Install all new packings and retainers." The internal snap rings qualified as retainers, and therefore were to be replaced during re-assembly of the actuators.

According to the airplane maintenance records "all three MG [main landing gear] door cylinders [actuators]" were "rebuilt" with "new O-rings" in July 2014, when the airplane had a TT of about 1,968 hrs. That entry was the most recent entry concerning the landing gear. The entry did not cite any additional details about the rebuilds, including whether new internal snap rings were installed. Discussions with the operator's Director of Maintenance indicated that the snap rings likely were not replaced during the actuator rebuild. The airplane accumulated more than 750 hours of operation between the actuator rebuild and the failure.

Meteorological Information and Flight Plan

Conditions at Accident Site: Visual Conditions
Condition of Light: Day
Observation Facility, Elevation: LWS, 1442 ft msl
Distance from Accident Site: 0 Nautical Miles
Observation Time: 1842 MDT
Direction from Accident Site: 0°
Lowest Cloud Condition: Clear
Visibility:  10 Miles
Lowest Ceiling: None
Visibility (RVR):
Wind Speed/Gusts: 5 knots /
Turbulence Type Forecast/Actual:
Wind Direction: 90°
Turbulence Severity Forecast/Actual:
Altimeter Setting: 29.85 inches Hg
Temperature/Dew Point: 39°C / 5°C
Precipitation and Obscuration: No Obscuration; No Precipitation
Departure Point: Lewiston, ID (LWS)
Type of Flight Plan Filed: Unknown
Destination: Lewiston, ID (LWS)
Type of Clearance: None
Departure Time: 1300 PDT
Type of Airspace: Class D

The 1842 automated weather observation at LWS included winds from 090° at 5 knots, visibility 10 miles, clear skies, temperature 39°C, dew point 5°C, and an altimeter setting of 29.85 inches of mercury.

Airport Information

Airport: Lewiston Nez Perce County (LWS)
Runway Surface Type: Asphalt
Airport Elevation: 1442 ft
Runway Surface Condition: Dry
Runway Used: 30
IFR Approach: None
Runway Length/Width: 5000 ft / 100 ft
VFR Approach/Landing: Unknown

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: 46.375000, -117.010000 (est) 

The airplane came to rest near the runway 30 centerline, about 100 ft prior to taxiway F. All three landing gear were retracted in their wells, but the landing gear doors were in varying positions of transit. All airframe damage was confined to the airplane belly skins and structure, and the landing gear doors. The tips of the rear propeller blades displayed minor grinding damage consistent with runway contact with the engine operating. Post accident examination revealed that the runway slide had ground through several of the lower skin panels and structural members, substantially damaging the airplane.

Examination of the landing gear system revealed that the same failure had occurred in both the left and right main landing gear door actuators, but for different reasons. In each case, the single internal snap ring that functioned as the travel stop and retaining device for the actuator rod in each actuator cylinder had been liberated from its retention groove in the cylinder, but remained captive on the actuator rod. Liberation of the snap ring enables hyper-extension (overtravel) of the actuator rod, which then permits most or all of the hydraulic fluid to exit the hydraulic system via the actuator. The landing gear hydraulic system was not equipped with any hydraulic fuses, and the reservoir was found to be empty. Loss of most or all of the hydraulic fluid renders the landing gear system inoperative in both the normal and emergency modes. No damage to the snap rings or the actuator cylinders from either door was observed.

Both main doors were found open about 90°, so that their inboard free edges, which were closest to the airplane centerline when the doors were closed, had translated outboard and down. Because the MLG remained in their respective wheel wells, these door edges contacted the runway on touchdown. The inboard edge of the right door was only slightly damaged by runway contact, but according to a technician who examined the airplane shortly after the accident, the left door was "missing about 3-4 inches of material" along its inboard edge, due to abrasion by runway contact. This door-damage evidence was consistent with the liberation of the snap ring from the right actuator occurring first, followed by significant loss of hydraulic fluid, and subsequent disabling of the landing gear system. The left actuator was hyperextended (and its snap ring liberated) by door loading due to runway contact.

Subsequent to the examination, the actuator rods and internal snap rings were re-inserted into their respective actuators, and the hydraulic system was replenished with fluid. The landing gear system was operationally tested while the airplane was supported by jacks. The system performed normally; the landing gear was able to be retracted and extended multiple times with no anomalies or failures. No other mechanical deficiencies with the landing gear system were detected.

Additional Information

Snap Ring Problems and Alternatives

The operator reported that a Canadian operator with 18 Cessna 337 airplanes had 3 occurrences of snap ring liberation and landing gear failure since 1980. A search of FAA Service Difficulty Reports (SDRs) revealed additional snap ring liberation occurrences.

The airplane manufacturer offered an alternate-design actuator that could be installed as a direct replacement (no other changes) on the accident model airplane. The alternate design actuator replaced the snap ring with a threaded cap on the end of the actuator cylinder; this design afforded a more secure retention system for the actuator rod.

At least one aftermarket company, RT Aerospace, developed an alternative for the airplane manufacturer's main landing gear doors. This alternative was approved via an FAA supplemental type certificate (STC). This design replaced the moving doors and their actuation systems with fixed panels that had cutouts for the landing gear. The company website stated that this hardware reduced the "high drag" due to the original door configuration, and improved reliability and safety by eliminating 2 actuators and 4 hydraulic lines. This STC modification was not installed on the accident airplane at the time of the event, but the operator reported that they installed it when the airplane was repaired after the accident.

Cessna 152, N6306P: Accident occurred April 19, 2020 near Corona Municipal Airport (KAJO), Riverside County, California -and- Accident occurred July 02, 2019 at Tracy Municipal Airport (KTCY), San Joaquin County, California

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. 

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

Additional Participating Entity: 
Federal Aviation Administration / Flight Standards District Office; Riverside, California


Location: Corona, CA 
Accident Number: WPR20LA126
Date & Time: April 19, 2020, 10:40 Local
Registration: N6306P
Aircraft: Cessna 152 
Injuries: 2 Serious
Flight Conducted
Under: Part 91: General aviation - Personal

On April 19, 2020, about 1040 Pacific daylight time, a Cessna 152 airplane N6306P, was substantially damaged when it was involved in an accident near Corona, California. The private pilot and passenger were seriously injured. The airplane was operated as a Title 14 Code of Federal Regulations (CFR) Part 91 personal flight.

The passenger reported that he was managing ForeFlight on his iPad while the pilot was flying the airplane. The pilot started and taxied uneventfully; a runup was conducted and no anomalies were noted. The pilot departed and completed one circuit in the pattern and a touch and go. Shortly after, while turning onto the crosswind leg of the traffic pattern, the pilot stated, "oh we are going down". The passenger looked up confused and within about 10 seconds they impacted something and came to rest upside down on a roadway. Due to noise cancelling headphones, he did not hear the engine quit, nor did he hear it make any abnormal noise.

The airplane has been recovered to a secure location for further examination.

Aircraft and Owner/Operator Information

Aircraft Make: Cessna 
Registration: N6306P
Model/Series: 152 
Aircraft Category: Airplane
Amateur Built: No
Operator: On file
Operating Certificate(s) Held: None
Operator Designator Code:

Meteorological Information and Flight Plan

Conditions at Accident Site: VMC
Condition of Light: Day
Observation Facility, Elevation: AJO,533 ft msl
Observation Time: 10:56 Local
Distance from Accident Site: 1 Nautical Miles
Temperature/Dew Point: 17°C /10°C
Lowest Cloud Condition: Clear
Wind Speed/Gusts, Direction: 6 knots / , 320°
Lowest Ceiling: Overcast / 4200 ft AGL 
Visibility: 10 miles
Altimeter Setting: 30.09 inches Hg 
Type of Flight Plan Filed: None
Departure Point: Corona, CA (AJO)
Destination: Riverside, CA (RIR)

Wreckage and Impact Information

Crew Injuries: 1 Serious 
Aircraft Damage: Substantial
Passenger Injuries: 1 Serious 
Aircraft Fire: None
Ground Injuries: N/A 
Aircraft Explosion: None
Total Injuries: 2 Serious 
Latitude, Longitude: 33.891944,-117.601387 (est)

April 19, 2020


A pilot and passenger were injured Sunday, April 19, when the single-engine plane they were in crashed and flipped over a short distance from Corona Municipal Airport, firefighters said.

There was no fire from the 10:48 a.m. crash on a service road southwest of the airport. The pilot had moderate injuries and the passenger, who was walking outside the aircraft after the crash, had minor injuries, said Corona Fire Department spokesman John DeYoe.

Pilot and passenger, whom DeYoe described as men in their upper 50s, were hospitalized. The airport remained in operation, DeYoe said.

The plane was engaged in a training exercise, DeYoe said. “They were doing two touchdowns (landing-and-takeoffs) and on the second touchdown they came around and they lost power and nosed into a service road … the plane then flipped over onto its top,” he said.

Because there was no fire, the first fire engine at the scene had trouble finding the downed aircraft, which was outside the airport property, DeYoe said.

A drone from the Corona Police Department was sent airborne, and its camera spotted the downed craft, DeYoe said. “There’s a lot of things you can utilize those things for,” he said.

The plane’s registration with the FAA said it is a Cessna 152 based in Corona, with the notation “sale reported” in place of an owner’s name.

DeYoe said the National Transportation and Safety Board was not sending an investigator to the site because of coronavirus contagion restrictions. Instead, the NTSB requested that police take specific photos of the wreckage, he said.

“From the sounds of it, they are not going to be out at all,” DeYoe said, due to the travel restrictions, and also because of the type of crash — the plane was still intact, and there were no serious injuries

DeYoe said he did not know Sunday afternoon whether it was an instructor-and-student flight or just two men aboard the plane with one practicing the touchdowns.

In January, four people died in a fiery single-engine plane crash during takeoff at Corona Municipal Airport.

https://www.pe.com

July 02, 2019
View of damaged left wing.

Additional Participating Entity:
Federal Aviation Administration / Flight Standards District Office; Oakland, California 

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


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


Location: Tracy, CA
Accident Number: GAA19CA390
Date & Time: 07/02/2019, 1000 PDT
Registration: N6306P
Aircraft: Cessna 152
Aircraft Damage: Substantial
Defining Event: Loss of control on ground
Injuries: 1 None
Flight Conducted Under: Part 91: General Aviation - Instructional 

The operator reported that during the solo student pilot's landing, the airplane immediately veered left, exited the runway and the left wing struck a paving vehicle on the adjacent taxiway.

The airplane sustained substantial damage to the left wing.

The operator reported that there was no preimpact mechanical malfunctions or failures that would have precluded normal operations.

The operator and the student pilot did not submit the National Transportation Safety Board Pilot/Operator Aircraft Accident/Incident Report Form 6120.1.

Student Pilot Information

Certificate: Student 
Age: 40, Male
Airplane Rating(s): None
Seat Occupied: Left
Other Aircraft Rating(s): None
Restraint Used:
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: 04/12/2019
Occupational Pilot: No
Last Flight Review or Equivalent:
Flight Time:  (Estimated) 90 hours (Total, all aircraft), 38 hours (Total, this make and model)

Aircraft and Owner/Operator Information

Aircraft Make: Cessna
Registration: N6306P
Model/Series: 152 No Series
Aircraft Category: Airplane
Year of Manufacture: 1981
Amateur Built: No
Airworthiness Certificate: Normal; Utility
Serial Number: 15284997
Landing Gear Type: Tricycle
Seats: 2
Date/Type of Last Inspection: 05/03/2019, 100 Hour
Certified Max Gross Wt.: 1669 lbs
Time Since Last Inspection:
Engines: 1 Reciprocating
Airframe Total Time: 7926.3 Hours as of last inspection
Engine Manufacturer: Lycoming
ELT:
Engine Model/Series: O-235 SERIES
Registered Owner: CC Aviation Inc
Rated Power:
Operator: CC Aviation Inc
Operating Certificate(s) Held: None
Operator Does Business As: Skyview Aviation
Operator Designator Code:

Meteorological Information and Flight Plan

Conditions at Accident Site: Visual Conditions
Condition of Light: Day
Observation Facility, Elevation: KSCK, 27 ft msl
Distance from Accident Site: 16 Nautical Miles
Observation Time: 1655 UTC
Direction from Accident Site: 40°
Lowest Cloud Condition: Clear
Visibility:  9 Miles
Lowest Ceiling: None
Visibility (RVR):
Wind Speed/Gusts: Light and Variable /
Turbulence Type Forecast/Actual: None / None
Wind Direction: Variable
Turbulence Severity Forecast/Actual: N/A / N/A
Altimeter Setting: 29.95 inches Hg
Temperature/Dew Point: 24°C / 8°C
Precipitation and Obscuration: No Obscuration; No Precipitation
Departure Point: Tracy, CA (TCY)
Type of Flight Plan Filed: None
Destination:  Tracy, CA (TCY)
Type of Clearance: None
Departure Time:  PDT
Type of Airspace: Class G

Airport Information

Airport: Tracy Muni (TCY)
Runway Surface Type: Asphalt
Airport Elevation: 193 ft
Runway Surface Condition:Dry 
Runway Used: 30
IFR Approach:None 
Runway Length/Width: 4001 ft / 75 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: 37.688889, -121.441667 (est)

Loss of Engine Power (Partial): Ryan Navion B, N5329K; fatal accident occurred July 17, 2018 near Truckee-Tahoe Airport (KTRK), Nevada County, California

View of fuel selector and position observed at accident site.




Top spark plugs.




Bottom spark plugs.





































Kenneth Reynolds "Ken" Whittall-Scherfee (pilot) 

Peter Jackson (passenger)

The National Transportation Safety Board traveled to the scene of this accident.

Additional Participating Entities: 

Federal Aviation Administration / Flight Standards District Office; Reno, Nevada
Lycoming Engines; Williamsport, Pennsylvania

Aviation Accident Factual 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/N5329K

Location: Truckee, CA
Accident Number: WPR18FA198
Date & Time: 07/17/2018, 0739 PDT
Registration: N5329K
Aircraft: Ryan NAVION
Aircraft Damage: Substantial
Defining Event: Loss of engine power (partial)
Injuries: 2 Fatal, 1 Serious
Flight Conducted Under: Part 91: General Aviation - Personal 

On July 17, 2018, about 0739 Pacific daylight time, a Ryan Navion B, N5329K, was substantially damaged when it impacted terrain shortly after takeoff from Truckee-Tahoe Airport (TRK), Truckee, California. The private pilot and one passenger were fatally injured; the second passenger was seriously injured. The airplane was registered to and operated by the pilot as a Title 14 Code of Federal Regulations Part 91 personal flight. Visual meteorological conditions prevailed in the area and no flight plan was filed for the local flight, which was originating at the time of the accident.

According to the fueler on duty and fuel records provided by the airport's fixed base operator, about 20 minutes before departure, the pilot purchased 15 gallons of 100 low lead (100LL) aviation fuel, all of which was added to the right wing tank. According to local air traffic control transcripts and an audio recording provided by the Federal Aviation Administration (FAA), about 2 minutes 24 seconds after takeoff, the pilot reported to the tower controller that he had experienced a "power failure" and would be returning to the airport. The controller cleared the pilot to land on any runway, then asked if he needed any assistance; the pilot did not respond, and there were no further communications from the pilot. The airplane impacted terrain about 1 nautical mile southeast of the departure end of runway 11.

The local fire department incident commander stated that a witness reported that he witnessed the plane [flying] low and trying to make a sharp turn back towards the airport, and that the engine seemed like it was "sputtering". He said that it then lost altitude and glided into the creek.

The surviving passenger reported that on the morning of the accident, after the fueling was complete and having watched the pilot do his preflight, they boarded the airplane with the pilot occupying the left front seat, he the right front seat, and his husband the left rear seat. He stated that he remembered taxiing out to the run-up area prior to takeoff, however, does not remember anything after that.

An airport operations maintenance supervisor who witnessed the airplane take off stated that it "was climbing at an unusually steep angle." Its rate of climb decreased, and he saw the landing gear partially extend, then retract again. He heard the pilot report the loss of power to the tower controller and lost sight of the airplane shortly thereafter.

Pilot Information

Certificate: Private
Age: 60, Male
Airplane Rating(s): Single-engine Land
Seat Occupied: Left
Other Aircraft Rating(s): None
Restraint Used:
Instrument Rating(s): Airplane
Second Pilot Present: No
Instructor Rating(s): None
Toxicology Performed: Yes
Medical Certification: Class 3 With Waivers/Limitations
Last FAA Medical Exam: 05/18/2017
Occupational Pilot: No
Last Flight Review or Equivalent:
Flight Time:  943 hours (Total, all aircraft), 1 hours (Total, this make and model)

The pilot, age 70, held a private pilot certificate with ratings for airplane single-engine land and instrument airplane. The pilot's personal flight records were not located and his total flight experience, recency of experience, and experience in the accident airplane could not be determined.

The pilot held a third-class FAA airman medical certificate with a limitation that he must have glasses available for near vision. On the application for that certificate, dated May 18, 2017, the pilot reported 973 total hours of flight experience, with 8 hours during the previous 6 months. 

Aircraft and Owner/Operator Information

Aircraft Make: Ryan
Registration: N5329K
Model/Series: NAVION B
Aircraft Category: Airplane
Year of Manufacture: 1951
Amateur Built: No
Airworthiness Certificate: Normal
Serial Number: NAV-4-2229-B
Landing Gear Type: Retractable - Tricycle
Seats: 4
Date/Type of Last Inspection: 04/06/2017, Annual
Certified Max Gross Wt.: 2750 lbs
Time Since Last Inspection:
Engines: 1 Reciprocating
Airframe Total Time:
Engine Manufacturer: Lycoming
ELT: Installed, not activated
Engine Model/Series: GO-480-G1D6
Registered Owner: On file
Rated Power: 280 hp
Operator: On file
Operating Certificate(s) Held: None

The airplane, serial number NAV-4-2229-B, was a single-engine, all-metal airplane of semi-monocoque design equipped with retractable landing gear, wing flaps, and a constant-speed propeller.

The airplane's most recent annual inspection was performed on April 6, 2017, at a tachometer time of 569.99 hours, a total airframe time of 3,461.92 hours, and 564.72 hours since the engine's last overhaul.

Maintenance records indicated that the carburetor was overhauled on September 1, 2004. Further, on February 2, 2008, at a tachometer time of 516.5 hours, the fuel selector was replaced with a new-style fuel selector, part number 147-30013-203, in accordance with (IAW) Navion Service Bulletin No. 101A.

On February 1, 2009, at a tachometer time of 594.8 hours, Airworthiness Directive 2008-05-14 was completed IAW Navion Service Bulletin No. 106A, a one-time compliance inspection. The Bulletin stated in part, "If within the last 5 years or at any time after April 16, 2008 (the effective date of this AD) you have replaced the fuel selector valve with any of the valves specified in paragraphs (e)(3)(i) and (e)(3)(ii) of this AD, you may terminate the repetitive inspections and functional tests of the fuel selector valve required in paragraph (e)(2) of this AD.

The airplane was powered by a Lycoming GO-480-G1D6 six-cylinder, air-cooled, geared-drive, carburetor-equipped engine rated at 280 horsepower, which was not original to the airplane.

A review of FAA airworthiness records and partial airplane maintenance records revealed no information regarding the installation of the engine. A search of the FAA Supplemental Type Certificate database found no STC's related to the Navion B aircraft model applicable to the accident airplane.

Meteorological Information and Flight Plan

Conditions at Accident Site: Visual Conditions
Condition of Light: Day
Observation Facility, Elevation: TRK, 5901 ft msl
Distance from Accident Site: 1 Nautical Miles
Observation Time: 0745 PDT
Direction from Accident Site:345° 
Lowest Cloud Condition: Clear
Visibility:  10 Miles
Lowest Ceiling: None
Visibility (RVR):
Wind Speed/Gusts: Calm /
Turbulence Type Forecast/Actual: None / None
Wind Direction:
Turbulence Severity Forecast/Actual: N/A / N/A
Altimeter Setting: 30.34 inches Hg
Temperature/Dew Point: 12°C / 6°C
Precipitation and Obscuration: No Obscuration; No Precipitation
Departure Point: Truckee, CA (TRK)
Type of Flight Plan Filed: None
Destination: Truckee, CA (TRK)
Type of Clearance: None
Departure Time: 0736 PDT
Type of Airspace: Class D

At 0745, the weather reporting facility located at TRK reported calm wind, 10 miles visibility, light haze, clear sky, temperature 12°C, dew point 6°C, and an altimeter setting of 30.34 inches of mercury. The calculated density altitude about the time of the accident was 6,400 ft.

Airport Information

Airport: Truckee-Tahoe Airport (KTRK)
Runway Surface Type: Asphalt
Airport Elevation: 5901 ft
Runway Surface Condition: Dry
Runway Used:11 
IFR Approach: None
Runway Length/Width: 7000 ft / 100 ft
VFR Approach/Landing: Forced Landing 

Wreckage and Impact Information

Crew Injuries: 1 Fatal
Aircraft Damage: Substantial
Passenger Injuries: 1 Fatal, 1 Serious
Aircraft Fire: None
Ground Injuries: N/A
Aircraft Explosion: None
Total Injuries: 2 Fatal, 1 Serious
Latitude, Longitude: 39.301944, -120.125278 (est) 

The airplane impacted terrain about 0.98 mile southeast (160° magnetic) of the departure end of runway 11. The airplane came to rest upright adjacent to a creek on a heading of about 315° magnetic at an elevation of 5,825 ft mean sea level. Debris was contained within about 5 ft of the main wreckage, which included a separated propeller blade. There was no visible debris path or impact marks surrounding the main wreckage.

Both wings remained attached to the fuselage. The right wing exhibited leading edge crushing from the wingtip to about 30 inches inboard. Upward crushing on the bottom of the leading edge was observed near the wing root and in various areas throughout the span of the right wing. The aileron and flap remained attached to their respective mounts. The flap appeared to be in the retracted position. The right main landing gear appeared to be in the retracted position.

The left wing appeared to be mostly undamaged. The aileron and flap remained attached to their respective mounts. The flap and landing gear were in the retracted position.

The fuselage was mostly intact. The structure just aft of the cabin area was buckled and bent to the right. The empennage was intact and undamaged. The rudder, vertical stabilizer, horizontal stabilizers, and elevators remained attached to their respective attach points. Control continuity was established from the cockpit area to all flight control surfaces.

The engine was partially attached to the airframe and bent downward at an approximate 10-15° angle. When the top cowling was removed, oil residue was observed covering the front of the engine. The propeller hub remained attached. One of the three propeller blades was separated from the hub. Chordwise scratches were observed on all three blades.

The engine, which had been removed from the airframe by retrieval personnel during the recovery process, sustained moderate impact damage to the underside, including the carburetor and exhaust system. Visual examination of the engine revealed no evidence of pre-impact catastrophic mechanical malfunction or fire.

The wreckage was removed from the site to a secure storage facility for further examination.

Both the engine-driven fuel pump and the electric fuel boost pump were removed. Subsequent bench testing revealed that both components operated normally.

The fuel selector, located on the cockpit floor between the two front seats, was observed in the OFF position. Two local fire department incident commanders provided instruction to their first responder staff to turn the fuel off, which was consistent with their operational procedures. It was not determined during the investigation what position the fuel selector was in prior to it being turned to the OFF position. When rotated by hand, the selector functioned normally; all detents were identified when the handle was rotated. The fuel selector could not be removed due to impact damage to the airframe.

Two samples of residual fuel tested negative for water contamination.

The engine crankshaft, which was rotated by hand using the propeller, was free to rotate in both directions. Thumb compression was obtained in proper order on all six cylinders. Mechanical continuity was established throughout the rotating group, valve train, and accessory section.

The top spark plugs were removed. The spark plugs electrodes remained mechanically undamaged. When compared to the Champion Spark Plugs Check-A-Plug chart AV-27, the spark plug electrodes displayed coloration consistent with normal operation.

Normal lifting action was observed at each rocker assembly. Clean, uncontaminated oil was observed at all six rocker box areas. The bottom spark plugs were removed. Borescope inspection of each cylinder combustion chamber revealed no anomalies.

The left and right magnetos remained securely attached at their respective mounting pads. The ignition harness was secure at each magneto. The magneto to engine timing was observed at 25° before top dead center of cylinder No. 1.

The magnetos were removed for examination. Each magneto produced spark at the end of the respective spark plug lead during hand rotation of the drive. The drives of each magneto remained intact and undamaged.

The carburetor was displaced from the engine due to impact forces. The portion that remained attached at the mounting pad was secure. The fracture surface signatures were consistent with overload. The throttle/mixture controls were found securely attached at their respective control arms. The castellated nut and cotter pin remained secure and the serrated interface at the throttle arm remained securely mated.

The carburetor was disassembled for further examination. The carburetor fuel inlet filter screen was free of visible contaminants. The outer regulator diaphragm (fuel), inner regulator diaphragm (air), and power enrichment rubber diaphragms were ruptured/torn. Microscopic examination of the fracture surfaces of the carburetor inner regulator, outer regulator, and the enrichment valve diaphragms revealed features consistent with shear and tension fractures likely sustained during the impact.

The engine-driven fuel pump was attached to the engine at the mounting pad. The input fuel line had been removed at the firewall by the retriever. The fuel pump output hose had been removed at the fuel pump by the retriever. The fuel pump was removed for examination. The drive was free to rotate.

Fluid consistent with the appearance and odor of aviation fuel was found within the carburetor during disassembly; testing of the fuel revealed no water contamination.

Due to the extreme impact damage to the airframe, the fuel system, gascolator screen, vent lines, and fuel lines were not examined.

The examinations of the engine and the airframe did not reveal any mechanical malfunctions that would have precluded normal operation.

Medical And Pathological Information

On July 18, 2018, the Placer County Office of the Sheriff-Coroner, Auburn, California, performed an autopsy on the pilot. The cause of death was attributed to multiple blunt injuries.

Toxicology testing performed by the FAA Forensic Sciences Laboratory was negative for all substances tested.