Monday, November 14, 2016

Cessna A185F Skywagon, N4918Q: Incident occurred June 05, 2021 and Accident occurred November 12, 2016

Federal Aviation Administration / Flight Standards District Office; Anchorage, Alaska

June 05, 2021:  Aircraft experienced engine issue and landed on the beach. 


Date: 05-JUN-21
Time: 15:50:00Z
Regis#: N4918Q
Aircraft Make: CESSNA
Aircraft Model: 185
Event Type: INCIDENT
Highest Injury: NONE
Aircraft Missing: No
Damage: NONE
Activity: PERSONAL
Flight Phase: EN ROUTE (ENR)
Operation: 91
City: HOMER
State: ALASKA








Aviation Accident Final Report - National Transportation Safety Board

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

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

Investigation Docket - National Transportation Safety Board:


Location: Ninilchik, Alaska
Accident Number: ANC17LA005
Date & Time: November 12, 2016, 12:15 Local 
Registration: N4918Q
Aircraft: Cessna A185
Aircraft Damage: Substantial
Defining Event: Sys/Comp malf/fail (non-power) 
Injuries: 2 None
Flight Conducted Under: Part 91: General aviation - Personal

Analysis

The airline transport pilot of the tailwheel-equipped airplane reported that the previous landing, which was flown by the pilot-rated passenger, was uneventful. The pilot then conducted the second landing, during which he reported that the right brake was not operating correctly, which resulted in asymmetrical braking. The airplane ground looped and sustained substantial damage.

Postaccident testing of the brake system revealed that the right brake had a small leak from both o-rings only while pressurized. Both o-rings on both calipers were replaced, the brake system was pressurized, and no further leaks were found.

Probable Cause and Findings

The National Transportation Safety Board determines the probable cause(s) of this accident to be:
A loss of brake system fluid due to leaks in the o-rings, which resulted in asymmetrical braking and a subsequent loss of directional control during the landing roll. 

Findings

Aircraft Hydraulic fluid - Fluid level
Aircraft Brake - Malfunction
Aircraft Braking capability - Attain/maintain not possible
Aircraft Master cylinder/brake valve - Malfunction
Aircraft Master cylinder/brake valve - Damaged/degraded

Factual Information

On November 12, 2016, about 1215 Alaska standard time, a tailwheel-equipped Cessna A185F airplane, N4918Q, sustained substantial damage during the landing roll at the Ninilchik Airport, Ninilchik, Alaska. The certificated airline transport pilot and the pilot-rated passenger sustained no injuries. The airplane was registered to, and operated by, the pilot as a visual flight rules (VFR) flight under the provisions of 14 Code of Federal Regulations (CFR) Part 91. Visual meteorological conditions prevailed at the time of the accident, and a VFR flight plan had been filed. The flight originated from the Soldotna Airport, Soldotna, Alaska, about 1200.

During a telephone interview with the National Transportation Safety Board (NTSB) investigator-incharge on November 13, the flying pilot, who was seated in the right seat at the time of the accident, stated that after an uneventful touchdown on the slightly wet and gravel surface of runway 10, the rightside brake system did not function as designed, which resulted in an asymmetrical braking condition. As the airplane continued the landing roll, the airplane ground looped to the left and the right wing and right horizontal stabilizer impacted the runway surface. The airplane came to rest on the runway without further incident.

The accident pilot stated that the previous landing was accomplished by the pilot-rated passenger and she reported no issues with the brake system during that landing sequence. The pilot further stated at the time of the accident, the wind condition originated from the north, about 10 to 15 knots. The airplane sustained substantial damage to the right wing and the right horizontal stabilizer.

In a written statement from a Federal Aviation Administration (FAA) aviation safety inspector (ASI) on November 16, he reported that he conducted an onsite examination of the airplane's brake system. He reported that he attempted to actuate the right brake, but the brake just went to the full travel stop. The right brake master cylinder filler plug was removed and a small tie wrap was utilized as a dip stick, and no fluid was observed on the tie wrap. The bottom of the fuselage and the right brake caliper were visually examined, and no signs of fluid leaks were observed. The accident pilot was asked if he previously observed the ground under the brake calipers at his parking space for evidence of any fluid leaks and the pilot reported he did look and did not observe any signs of fluid. The ASI additionally reported that the runway utilized by the accident pilot was in a useable condition, and that ice patches on the side of the runway were not a factor with the accident sequence.

In the recommendation section of the NTSB Accident/Incident Reporting Form 6120.1, the pilot stated that the accident may have been avoided if he depressed the brakes prior to landing to confirm both were functioning.

METEOROLOGICAL INFORMATION

The closest weather reporting facility was the Homer Airport, Homer, Alaska. At 1153, an Aviation Routine Weather Report (METAR) was reporting in part: wind from 080 degrees at 17 knots, gusting 24 knots; visibility 6 statute miles; sky condition broken 3,600 feet; temperature 45 degrees F; dew point 37 degrees F; altimeter 29.11 inHg.

TESTS AND RESEARCH

In a written statement from the accident pilot on December 20, he reported that the entire brake system was tested. The testing revealed that the right brake had an "extremely small leak (one drop)" from both o-rings at 500 pounds per square inch. The rest of the brake system appeared normal and no signs of brake fluid were found on the underside of the fuselage. He reported he assumed the leak was small and that only under pressure would it show signs of leaking, that is why no evidence of leaking was observed on any preflight activity prior to the accident. He further reported the o-rings on both calipers were replaced, the brake system was pressurized, and no further leaks were found.

In a written statement from the pilot on April 4, he reported that after replacing the brake lines, the right brake did not readily take fluid when pumped from the caliper. The right brake master cylinder was disassembled, and the spring was observed to be deformed. He reported that in certain positions, the spring would block the flow of fluid in or out.

ADDITIONAL INFORMATION

The FAA has published the Aviation Maintenance Technician Handbook – Airframe FAA-H-8083-31 (2012). This document discusses airplane brake systems and states in part:

Brake seals are very important. Without properly functioning seals, brake operation will be compromised or the brakes will fail. Over time, heat and pressure mold a seal into the seal groove and harden the material. Eventually, resilience is reduced and the seal leaks. New seals should be used to replace all seals in the brake assembly. Acquire seals by part number in a sealed package from a
reputable supplier to avoid bogus seals and ensure the correct seals for the brake assembly in question. Check to ensure the new seals have not exceeded their shelf life, which is typically three years from the cure date.

History of Flight

Landing-landing roll Sys/Comp malf/fail (non-power) (Defining event)
Landing-landing roll Miscellaneous/other
Landing-landing roll Loss of control on ground
Landing-landing roll Collision with terr/obj (non-CFIT)

Pilot Information

Certificate: Airline transport 
Age: 68, Male
Airplane Rating(s): Single-engine land; Single-engine sea; Multi-engine land
Seat Occupied: Right
Other Aircraft Rating(s): None
Restraint Used: 3-point
Instrument Rating(s): Airplane 
Second Pilot Present: Yes
Instructor Rating(s): None 
Toxicology Performed: No
Medical Certification: Class 2 Waiver time limited special
Last FAA Medical Exam: January 28, 2016
Occupational Pilot: No 
Last Flight Review or Equivalent: June 1, 2016
Flight Time: (Estimated) 8000 hours (Total, all aircraft), 3000 hours (Total, this make and model), 7700 hours (Pilot In Command, all aircraft), 150 hours (Last 90 days, all aircraft), 10 hours (Last 30 days, all aircraft), 0.5 hours (Last 24 hours, all aircraft)

Pilot-rated passenger Information

Certificate: Private
Age: Female
Airplane Rating(s): Single-engine land; Single-engine sea
Seat Occupied: Left
Other Aircraft Rating(s): None
Restraint Used: 3-point
Instrument Rating(s): Airplane 
Second Pilot Present: Yes
Instructor Rating(s): None
Toxicology Performed: No
Medical Certification: Class 3 Unknown 
Last FAA Medical Exam: February 1, 2017
Occupational Pilot: No
Last Flight Review or Equivalent:
Flight Time: (Estimated) 0 hours (Total, all aircraft), 0 hours (Total, this make and model)

Aircraft and Owner/Operator Information

Aircraft Make: Cessna 
Registration: N4918Q
Model/Series: A185 F 
Aircraft Category: Airplane
Year of Manufacture: 1978
Amateur Built: No
Airworthiness Certificate: Normal 
Serial Number: 18503575
Landing Gear Type: Tailwheel 
Seats: 2
Date/Type of Last Inspection: April 1, 2016 
Annual Certified Max Gross Wt.: 3350 lbs
Time Since Last Inspection: 
Engines: 1 Reciprocating
Airframe Total Time: 4587.3 Hrs as of last inspection
Engine Manufacturer: Continental Motors
ELT: C126 installed, not activated
Engine Model/Series: IO-520D
Registered Owner:
Rated Power: 300 Horsepower
Operator: On file 
Operating Certificate(s) Held: None

Meteorological Information and Flight Plan

Conditions at Accident Site: Visual (VMC)
Condition of Light: Day
Observation Facility, Elevation: PAHO,73 ft msl
Distance from Accident Site: 23 Nautical Miles
Observation Time: 20:53 Local
Direction from Accident Site: 173°
Lowest Cloud Condition:
Visibility: 6 miles
Lowest Ceiling: Broken / 3600 ft AGL 
Visibility (RVR):
Wind Speed/Gusts: 17 knots / 24 knots
Turbulence Type Forecast/Actual:  / None
Wind Direction: 80° 
Turbulence Severity Forecast/Actual:  / N/A
Altimeter Setting: 29.11 inches Hg 
Temperature/Dew Point: 7°C / 3°C
Precipitation and Obscuration: Moderate - None - Rain
Departure Point: SOLDOTNA, AK (SXQ)
Type of Flight Plan Filed: VFR
Destination: Ninilchik, AK (NIN)
Type of Clearance: None
Departure Time:
Type of Airspace: Class G

Airport Information

Airport: NINILCHIK NIN
Runway Surface Type: Gravel
Airport Elevation: 276 ft msl 
Runway Surface Condition: Wet
Runway Used: 10 IFR 
Approach: None 
Runway Length/Width: 2400 ft / 60 ft VFR 
Approach/Landing: Stop and go; Traffic pattern

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: 60.02,-151.589172(est)

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