# NTSB ERA18LA154: Cessna 421, N427JM, Sandersville, GA, May 21, 2018 - Type: NTSB accident investigation - Classification: Accident · No injuries · Class 3 · Limited · Final report - Date: May 21, 2018, 13:10 local (17:10 UTC) - Place: Sandersville, GA - Coordinates: 32.966667, -82.838058 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=32.9667&lon=-82.8381&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing-landing roll: Landing gear collapse](https://openairdocs.org/ntsb-events/094) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Eastern Region Aviation - Parties: FAA FSDO - NTSB case key (mKey): 97353 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA18LA154 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/97353/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=97353 - Page: https://openairdocs.org/ntsb/ERA18LA154 ## Probable cause A nose landing gear collapse for reasons that could not be determined based on the available information. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Landing gear system: nose/tail landing gear](https://openairdocs.org/ntsb-findings/01023220): Aircraft › Aircraft systems · Malfunction (probable cause); cases with it: [Cessna 421C, 1 case](https://openairdocs.org/ntsb-findings/01023220/cases.md?model=2076016), [All aircraft, 185 cases](https://openairdocs.org/ntsb-findings/01023220/cases.md) - [Landing gear system: gear position and warning](https://openairdocs.org/ntsb-findings/01023260): Aircraft › Aircraft systems · Malfunction; cases with it: [Cessna 421C, 2 cases](https://openairdocs.org/ntsb-findings/01023260/cases.md?model=2076016), [All aircraft, 37 cases](https://openairdocs.org/ntsb-findings/01023260/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Landing-landing roll: Landing gear collapse](https://openairdocs.org/ntsb-events/094) (defining event); cases with it: [Cessna 421C, 7 cases](https://openairdocs.org/ntsb-events/094/sequence.md?model=2076016), [All aircraft, 1,787 cases](https://openairdocs.org/ntsb-events/094/sequence.md) ## Analysis The pilot reported that the flight was uneventful and during the approach for landing, he placed the landing gear handle in the down position and observed three green landing gear lights, indicating that the gear was down and locked. Shortly after touchdown, the nose landing gear collapsed into the retracted position. The airplane’s nose impacted the runway and the airplane skidded to a stop, resulting in substantial damage to the airframe. After the airplane stopped, the landing gear position lights indicated that all of the landing gear were extended and locked into position. A mechanic who saw the landing and assisted in removing the airplane from the runway after the accident reported that, during the attempt to move the airplane, they lifted the nose off the ground and tried unsuccessfully to move the nose landing gear into the down and locked position. Postaccident testing of the nose landing gear actuator revealed no discrepancies. Although the green safe switch remained illuminated during the entire testing cycle, indicating a defective switch, this did not directly contribute to the collapse of the nose landing gear. Review of maintenance records showed no nose gear discrepancies over the previous 18 months. The reason for the nose landing gear collapse could not be determined based on the available information. ## Factual narrative On May 21, 2018, about 1310 eastern daylight time, a Cessna 421-C, N427JM, was substantially damaged when it was involved in an accident near Sandersville, Georgia. The commercial pilot was not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The pilot reported that the flight was uneventful; during the landing approach, he placed the landing gear handle in the down position and received three green landing gear lights, indicating that the gear was down and locked. He stated that, after the main landing gear touched down, “he didn’t feel any resistance from the nose nosewheel” when it settled onto the runway. The airplane continued to settle, and the nose impacted the runway. The pilot maintained directional control and attempted to maneuver the airplane off the runway onto a taxiway with differential braking as it skidded to a stop. After the airplane stopped, the landing gear position lights indicated that all gear were down and locked. A mechanic saw the landing and reported that the airplane looked “normal” on final approach. He heard the main landing gear touch down, followed by “something dragging.” After the airplane came to rest, he checked on the condition of the pilot, then attempted to remove the airplane from the runway. During the attempt to move the airplane from the runway, they lifted the nose off the ground, tried unsuccessfully to get the nose landing gear into the down and locked position, and ultimately strapped the landing gear in place to move the airplane. Examination of the airplane by a Federal Aviation Administration maintenance inspector revealed substantial damage, including buckling of the airframe on both sides of the nose landing gear well, and abrasion through to the airframe on the bottom of the nose and fuselage. The nose landing gear actuator was removed for detailed examination. The actuator was tested in the locked and unlocked position at the correct pressures with no leaks or discrepancies noted.; however, the green safe switch remained illuminated during the entire test, indicating a defective switch. The switch was brittle and appeared “very old.” A review of the airframe maintenance logbook revealed that, during the most recent annual inspection on July 10, 2017, a landing gear retraction test was conducted per the manufacturer’s service manual with no defects noted. On April 27, 2018, a logbook entry showed a main landing gear irregularity that was corrected. The landing gear was cycled 10 times with no defects noted with the nose landing gear. ## Aircraft - Registration: [N427JM](https://openairdocs.org/aircraft/N427JM), registered now, S/N 421C0103 (OpenAirDocs) - Reported make and model: CESSNA 421 (C) - Registry model: [Cessna 421C](https://openairdocs.org/model/cessna-421c) (registry code 2076016) (OpenAirDocs) - Category: Airplane - Serial number: 421C0103 - Year built: 1976 - Airframe hours: 4437.2 - Engines: Continental GTSIO520L4B 375 horsepower reciprocating; Continental GTISO520L4B 375 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Mabb Transport LLC - Registered owner: Mabb Transport LLC - Airworthiness certificate: Standard, Normal - Last inspection: Annual, July 11, 2017 - Departed: CTJ, Carrollton, GA - Destination: OKZ, Sandersville, GA - Flight plan: IFR - Airport: OKZ, Kaolin Field, runway 13, 5,016 × 75 ft, asphalt - Equipment: Stall warning system, Auto-pilot, Electronic multifunction display, Onboard weather, Satellite tracking device ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 64; injuries: none; commercial; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 2; last flight review January 15, 2018; seat: left; restraint: lap only; flight hours: 22,697 total, 948 in this make and model, 22,690 as pilot in command, 141 in the last 90 days, 44 in the last 30 days, 3 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 10 statute miles - Lowest ceiling: 3,700 ft broken - Temperature: 73 °F, dew point 70 °F - Altimeter: 29.70 inHg - Observed at: OKZ ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 20180521005709A](https://openairdocs.org/incident/20180521005709A), May 21, 2018: Cessna 421C, Sandersville, GA, Substantial damage. On 05/21/2018 aircraft N427JM was on final approach to kokz, enroute from kctj, and at 2 miles out the pilot selected gear down, approach flaps and saw that he… ## Docket (6 files) The files NTSB released with the investigation on November 3, 2021, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=97353. 22.8 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 11 pages, 2.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12427088&FileExtension=pdf&FileName=6120%20Accident%20Report_Redacted-Rel.pdf - Pilot statement (item 2, PDF, 1 page, 57 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12428061&FileExtension=pdf&FileName=Pilot%20Statement_Redacted-Rel.pdf - Eyewitness statement (item 3, PDF, 1 page, 417 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12427175&FileExtension=pdf&FileName=Eyewitness%20Statement_Redacted-Rel.pdf - Maintenance logbook excerpt (item 4, PDF, 10 pages, 18.7 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12427703&FileExtension=pdf&FileName=MX%20Logbook%20Excerpt_Redacted-Rel.pdf - Nose landing gear actuator bench test e-mail (item 5, PDF, 1 page, 93 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12428081&FileExtension=pdf&FileName=Actuator%20Test%20Result%20e-mail_Redacted-Rel.pdf - Photo array_airplane damage (item 6, PDF, 6 pages, 1.4 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12432414&FileExtension=pdf&FileName=Accident%20Site%20and%20Damage%20Photographs-Rel.pdf From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.