# NTSB ERA18LA176: Cessna 337, N86507, Atlanta, GA, May 29, 2018 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: May 29, 2018, 13:45 local (17:45 UTC) - Place: Atlanta, GA - Coordinates: 33.875556, -84.30194 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=33.8756&lon=-84.3019&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing: Sys/Comp malf/fail (non-power)](https://openairdocs.org/ntsb-events/330) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report November 6, 2019 - Report: Approved by Office Director - NTSB office: Eastern Region Aviation - Parties: FAA/FSDO - NTSB case key (mKey): 97557 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA18LA176 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/97557/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=97557 - Page: https://openairdocs.org/ntsb/ERA18LA176 ## Probable cause An area of pitting and corrosion on the surface of the aluminum hydraulic line connecting the emergency handle/pump to the electric hydraulic pump, which resulted in a loss of hydraulic pressure and the pilot’s inability to extend the landing gear. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Fluids: hydraulic fluid](https://openairdocs.org/ntsb-findings/01071015): Aircraft › Fluids/misc hardware · Fluid level (probable cause); cases with it: [Cessna 337E, 1 case](https://openairdocs.org/ntsb-findings/01071015/cases.md?model=2075721), [All aircraft, 33 cases](https://openairdocs.org/ntsb-findings/01071015/cases.md) - [Landing gear system: main landing gear](https://openairdocs.org/ntsb-findings/01023210): Aircraft › Aircraft systems · Failure (probable cause); cases with it: [Cessna 337E, 1 case](https://openairdocs.org/ntsb-findings/01023210/cases.md?model=2075721), [All aircraft, 241 cases](https://openairdocs.org/ntsb-findings/01023210/cases.md) - [Landing gear system: main landing gear](https://openairdocs.org/ntsb-findings/01023210): Aircraft › Aircraft systems · Fatigue/wear/corrosion (probable cause); cases with it: [Cessna 337E, 1 case](https://openairdocs.org/ntsb-findings/01023210/cases.md?model=2075721), [All aircraft, 241 cases](https://openairdocs.org/ntsb-findings/01023210/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Approach: Miscellaneous/other](https://openairdocs.org/ntsb-events/900); cases with it: [Cessna 337E, 1 case](https://openairdocs.org/ntsb-events/900/sequence.md?model=2075721), [All aircraft, 1,556 cases](https://openairdocs.org/ntsb-events/900/sequence.md) - [Landing: Sys/Comp malf/fail (non-power)](https://openairdocs.org/ntsb-events/330) (defining event); cases with it: [Cessna 337E, 1 case](https://openairdocs.org/ntsb-events/330/sequence.md?model=2075721), [All aircraft, 994 cases](https://openairdocs.org/ntsb-events/330/sequence.md) ## Analysis The private pilot was conducting a cross-country, personal flight. He stated that, while on approach to the destination airport, he was unable to extend the landing gear. He declared an emergency and attempted to pump the landing gear down via the emergency gear-extension handle to no avail. He then observed a large puddle of red hydraulic fluid on the floorboards near the hydraulic pump. The pilot realized that he would not be able to extend the gear and conducted a gear-up landing, which resulted in substantial damage to the lower fuselage. Postaccident examination of the airplane revealed that the hydraulic reservoir was nearly empty. When the emergency handle was activated, a stream of hydraulic fluid sprayed from the surface of the aluminum hydraulic line connecting the emergency handle/pump to the electric hydraulic pump that was mounted under and behind the pilot's instrument panel. Magnified visual examination of the leaking hydraulic line revealed an area of corrosion and pitting on the aluminum surface, which likely resulted in a loss of hydraulic pressure and the pilot's inability to extend the landing gear. ## Factual narrative On May 29, 2018, about 1345 eastern daylight time, a Cessna 337E, N86507, was substantially damaged during a gear-up landing at the DeKalb-Peachtree Airport (PDK), Atlanta, Georgia. The private pilot and the passenger were not injured. The airplane was co-owned and operated by the pilot as a Title 14 Code of Federal Regulations Part 91 personal flight. Visual meteorological conditions prevailed, and no flight plan was filed for the flight that departed North Perry Airport (HWO), Hollywood, Florida, about 0945.The pilot stated that he was unable to extend the landing gear while on approach to the airport. He declared an emergency and flew north of the airport where he attempted to pump the landing gear down via the emergency gear-extension handle. The pilot was unable to pump the gear down and observed a large puddle of red hydraulic fluid on the floorboards near the hydraulic pump. The pilot realized that he would not be able to extend the gear and made a gear-up landing on runway 21R, which resulted in substantial damage to the lower fuselage. A postaccident examination of the airplane revealed that when the emergency hydraulic pump actuator, located between the cockpit seats, was activated very little hydraulic resistance was noted when the emergency gear-extension handle was pumped. The hydraulic reservoir was nearly depleted. Further examination revealed that, as the emergency handle was activated, a stream of hydraulic fluid sprayed from the surface of the aluminum line connecting the emergency handle/pump to the electric hydraulic pump that was mounted under and behind the instrument panel of the pilot's side. The line was about 23 inches long. The plastic sheathing protecting the line was intact and removed to facilitate examination of the leaking area. There were no areas of line chafing noted on the line and no adjacent structure where chafing would occur. The leaking hydraulic line was removed and examined. A visual examination using 10x magnification revealed an area of corrosion and pitting on the aluminum surface. The affected area was about 0.75 inches long and covered about half the circumference of the tube. The pilot held a private pilot certificate with a rating for airplane single-engine land. His last Federal Aviation Administration (FAA) second-class medical was issued on December 12, 2017. Weather reported at the airport at 1359 included wind from 140° at 9 knots, visibility 10 miles, few clouds at 3,800 ft, scattered clouds at 4,900 ft, broken clouds at 6,000 ft, temperature 26° C, dew point 22° C, and an altimeter setting of 29.82 inHg. ## Aircraft - Registration: [N86507](https://openairdocs.org/deregistered/N86507-2021-04-05), registration cancelled 2021-04-05, S/N 33701212 (OpenAirDocs) - Reported make and model: CESSNA 337 (E) - Registry model: [Cessna 337E](https://openairdocs.org/model/cessna-337e) (registry code 2075721) (OpenAirDocs) - Registry engine: [Continental IO-360 series](https://openairdocs.org/engine/continental-io-360-series) (registry code 17025, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 33701212 - Year built: 1969 - Airframe hours: 1925.2 - Engines: CONT MOTOR IO-360 SER 210 horsepower reciprocating; CONT MOTOR IO-360 SER 210 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Annual, June 1, 2016 - Departed: PDK, Atlanta, GA - Destination: PDK, Atlanta, GA - Airport: PDK, Dekalb-Peachtree, runway 21R, 3,746 × 150 ft, asphalt - Equipment: Unknown ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 45; injuries: none; private; airplane ratings: single-engine land; medical: class 2, without waivers/limitations; last flight review May 29, 2018; seat: left; restraint: 3-point; flight hours: 3,087 total, 387 in this make and model ## Weather - Conditions: Visual (VMC), Day - Wind: 140° at 9 knots - Visibility: 10 statute miles - Lowest ceiling: 6,000 ft broken - Temperature: 79 °F, dew point 72 °F - Altimeter: 29.81 inHg - Observed at: PDK ## 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 20180529015099A](https://openairdocs.org/incident/20180529015099A), May 29, 2018: Cessna 337E, Atlanta, GA, Substantial damage. Pilot approached airport from south east, tower gave instructions to do left base to runway 21L. On final approach pilot followed through landing procedures… ## Docket (3 files) The files NTSB released with the investigation on April 1, 2019, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=97557. 1.3 MB in all. - Written Statement - Pilot (item 1, .PDF, 53 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40471507&FileExtension=.PDF&FileName=Written%20Statement%20-%20Pilot-Master.PDF - Photographs (item 2, .PDF, 2 photos, 486 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40471508&FileExtension=.PDF&FileName=Photographs-Master.PDF - Memorandum of Record - Hydraulics Exam (item 3, .PDF, 2 photos, 794 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40471509&FileExtension=.PDF&FileName=Memorandum%20of%20Record%20-%20Hydraulics%20Exam-Master.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.