# NTSB ERA23LA248: Raytheon B300, N680CB, Melbourne, FL, May 26, 2023 - Type: NTSB accident investigation - Classification: Accident · No injuries · Class 4 · Limited · Final report - Date: May 26, 2023, 09:58 local (13:58 UTC) - Place: Melbourne, FL - Coordinates: 28.104631, -80.643145 - Nearby events: https://openairdocs.org/map.md?lat=28.1046&lon=-80.6431&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Defining event: [Enroute-cruise: Part(s) separation from AC](https://openairdocs.org/ntsb-events/338) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed - Report: Approved by Office Director - Investigation class: Class 4 - Basic report with no Prelim publish - NTSB office: Eastern Region Aviation - Parties: FAA/FSDO - NTSB case key (mKey): 192247 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA23LA248 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/192247/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=192247 - Page: https://openairdocs.org/ntsb/ERA23LA248 ## Probable cause An inflight separation of the airplane’s airstair door for undetermined reasons. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Not determined](https://openairdocs.org/ntsb-findings/05000000): Not determined › Not determined · Unknown/Not determined (probable cause); cases with it: [All aircraft, 2,247 cases](https://openairdocs.org/ntsb-findings/05000000/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Enroute-cruise: Part(s) separation from AC](https://openairdocs.org/ntsb-events/338) (defining event); cases with it: [All aircraft, 563 cases](https://openairdocs.org/ntsb-events/338/sequence.md) ## Analysis The pilot of the multiengine turboprop airplane was flying over the ocean at FL340 when he heard an “explosion.” He quickly donned his oxygen mask, declared an emergency with air traffic control, and descended to 12,000 ft. The pilot subsequently diverted the flight and landed the airplane uneventfully. After landing he observed that the airstair door had completely separated from the fuselage. The inflight separation of the airstair door and resulting depressurization of the airplane’s cabin constituted substantial damage to the airframe. Post accident examination of the airplane revealed that portions of the airstair door hinges remained attached to the fuselage, the airstair door handle anchor had failed, and the door damper support was bent and its upper bolt sheared. The six door plate strikers on the fuselage were undamaged. The airstair door was not recovered and the condition of its securing mechanisms could not be examined. Given this information, the reason for the inflight separation of the door could not be determined. ## Aircraft - Registration: N680CB (not matched to a registry record) - Reported make and model: RAYTHEON AIRCRAFT COMPANY B300 - Category: Airplane - Serial number: FL-499 - Year built: 2006 - Airframe hours: 3604 - Engines: P&W PT6A-67A 1200 horsepower turbo prop; P&W PT6A-67A 1200 horsepower turbo prop - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Dalks Leasing Inc - Registered owner: Dalks Leasing Inc - Airworthiness certificate: Standard, Normal - Last inspection: Annual, February 28, 2023 - Departed: MYAT, Treasure Cay, OF - Destination: GSP, Greer, SC - Flight plan: IFR - Equipment: Angle of attack indicator, Auto-pilot, Data recorder, Electronic flight bag or handheld device, Electronic multifunction display, Electronic primary flight display, ADS-B, Onboard weather, Satellite tracking device, Stall warning system ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 74; injuries: none; airline transport; airplane ratings: single-engine land, multi-engine land, multi-engine sea, single-engine sea; instrument ratings: airplane; medical: class 3, without waivers/limitations; last flight review November 14, 2022; seat: left; restraint: 3-point; flight hours: 11,127 total, 835 in this make and model, 11,127 as pilot in command, 61 in the last 90 days, 42 in the last 30 days, 7.5 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 310° at 5 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 79 °F, dew point 70 °F - Altimeter: 29.83 inHg - Observed at: MLB - METAR: KMLB 261353Z 31005KT 10SM CLR 26/21 A2983 RMK AO2 SLP100 T02560211 ## 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 20230526005889A](https://openairdocs.org/incident/20230526005889A), May 26, 2023: Raytheon Aircraft Company B300, Melbourne, FL, Substantial damage. [privacy data omitted] Departed myat original destination kgsp diverted to kmlb. [privacy data omitted] Leveled at FL340 near MLB108098 being work by zma R2… ## Docket (4 files) The files NTSB released with the investigation on August 10, 2023, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=192247. 7.5 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 10 pages, 5.0 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=15719572&FileExtension=pdf&FileName=6120.1_Redacted-Rel.pdf - Pilot's written statement (item 2, PDF, 1 page, 1.7 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=15720826&FileExtension=pdf&FileName=PIlot%20statement_Redacted-Rel.pdf - Investigative photos (item 3, PDF, 2 pages, 660 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=15720530&FileExtension=pdf&FileName=Investigative%20Photo%27s-Rel.pdf - Memorandum for record a�� airframe examination by FAA (item 4, PDF, 1 page, 127 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=15804868&FileExtension=pdf&FileName=Memorandom-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.