# NTSB CHI99LA265: Cessna 310N, N310DE, Eden Prairie, MN, July 31, 1999 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: July 31, 1999, 11:00 local (16:00 UTC) - Place: Eden Prairie, MN - Coordinates: 44.860996, -93.430427 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=44.8610&lon=-93.4304&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report June 22, 2000 - Report: Approved by Office Director - NTSB case key (mKey): 46905 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI99LA265 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/46905/pdf - Page: https://openairdocs.org/ntsb/CHI99LA265 ## Probable cause maintenance personnel installed washers which were not large enough in diameter to prevent the retraction/extension scissors links from separating from each other. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Main gear collapsed, landing - flare/touchdown - miscellaneous,bolt/nut/fastener/clamp/spring - improper (cause) - maintenance,installation - improper, other maintenance personnel (cause) - landing gear,normal retraction/extension assembly - disconnected (cause) - Loss of control - on ground/water, landing - roll - directional control - not possible, pilot in command - On ground/water collision with object, landing - roll - object - airport sign/marker ## Analysis The pilot reported the flight was uneventful the left main landing gear 'broke' on touchdown. The airplane veered left where it contacted a taxiway information sign and the nose gear collapsed prior to the airplane coming to rest. The left main landing gear strut collapsed rearward damaging the left wing aft spar. Inspection of the left main gear revealed the upper and lower portions of the scissors link detached from each other allowing the lower portion of the strut to rotate within the upper portion of the strut. The bolt, washers, bushings, nut, and cotter pin remained attached to the upper link. There were three washers present near the head of the bolt. All three were painted white and had an outside diameter of 3/4 inch. There were four washer present at the castellated nut end of the bolt. None of these washers were painted and all of them had an outside diameter of 9/16 inch. This is the same outside diameter as the bushing and same inside diameter as the hole on the scissors link. ## Factual narrative On July 31, 1999, at 1100 central daylight time (cdt), a Cessna 310N, N310DE, experienced a left main gear collapse while landing on runway 27 at the Flying Cloud Airport, Eden Prairie, Minnesota. The pilot and passenger were not injured. The airplane was substantially damaged. The 14 CFR Part 91 personal flight was operating in visual meteorological conditions without a flight plan. The local flight originated from the Flying Cloud Airport, at 1000 cdt. The pilot reported that the flight was uneventful until the landing. He reported the airplane was lined up on the centerline of the runway in a 400 foot per minute descent during the approach. The pilot reported that the left main landing gear "broke" on touchdown. He stated the airplane "slowly drifted to the left" until the airplane came to a stop. The airplane contacted a taxiway information sign and the nose gear collapsed prior to the airplane coming to rest. Post accident inspection revealed the left main landing gear strut collapsed rearward damaging the left wing aft spar. Inspection of the left main gear revealed the upper and lower portions of the scissors link had become detached from each other allowing the lower portion of the strut to rotate within the upper portion of the strut. The bolt, washers, bushings, nut, and cotter pin remained attached to the upper link. There were three washers present near the head of the bolt. All three were painted white and had an outside diameter of 3/4 inch. There were four washer present at the castellated nut end of the bolt. None of these washers were painted and all of them had an outside diameter of 9/16 inch. This is the same outside diameter as the bushing and same inside diameter as the hole on the scissors link. ## Aircraft - Registration: [N310DE](https://openairdocs.org/deregistered/N310DE-2003-01-27), registration cancelled 2003-01-27, S/N 310N-0182, built 1968 (OpenAirDocs) - Reported make and model: Cessna 310N - Registry model: [Cessna 310N](https://openairdocs.org/model/cessna-310n) (registry code 2074234) (OpenAirDocs) - Registry engine: [Continental I0-470 series](https://openairdocs.org/engine/continental-i0-470-series) (registry code 17027, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 310N-0182 - Airframe hours: 5500 - Engines: Continental IO-470-VO 260 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Bahram Akradi - Registered owner: Windsor Aviation - Airworthiness certificate: Standard, Normal - Last inspection: Annual, July 1, 1998, 130 hours before - Departed: FCM - Destination: FCM - Airport: FCM, Flying Cloud, runway 27, 3,900 × 75 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 38; private; airplane ratings: multi-engine land, single-engine land; medical: class 2, valid medical--no waivers/lim.; seat: left; flight hours: 475 total, 170 in this make and model ## Weather - Conditions: Visual (VMC), Day - Wind: 320° at 11 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 79 °F, dew point 63 °F - Altimeter: 29.00 inHg - Observed at: FCM ## 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 19990731010209A](https://openairdocs.org/incident/19990731010209A), Jul 31, 1999: Cessna 310N, Minneapolis, MN, Substantial damage. Upon landing rw 27L, main gear collapsed. (.19) on July 31, 1999, at 1050 central daylight time (CDT), a Cessna 310N, N310DE, experienced a left main gear… 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.