# NTSB ERA19LA137: Pilatus PC12, N944BT, Fort Lauderdale, FL, March 24, 2019 - Type: NTSB accident investigation - Classification: Accident · No injuries · Class 3 · Limited · Final report - Date: March 24, 2019, 11:01 local (15:01 UTC) - Place: Fort Lauderdale, FL - Coordinates: 26.071388, -80.14167 - Nearby events: https://openairdocs.org/map.md?lat=26.0714&lon=-80.1417&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Defining event: [Enroute-climb to cruise: Aircraft structural failure](https://openairdocs.org/ntsb-events/337) - Highest injury: No injuries - Injuries: 3 uninjured - Status: Completed - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Eastern Region Aviation - Parties: FAA, PPG - NTSB case key (mKey): 99173 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA19LA137 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/99173/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=99173 - Page: https://openairdocs.org/ntsb/ERA19LA137 ## Probable cause Improper maintenance of the windshield, which resulted in delamination and in-flight depressurization. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Windows-windshield system: flight compartment windows](https://openairdocs.org/ntsb-findings/01035610): Aircraft › Aircraft structures · Malfunction (probable cause); cases with it: [Pilatus PC-12/45, 1 case](https://openairdocs.org/ntsb-findings/01035610/cases.md?model=7090551), [All aircraft, 42 cases](https://openairdocs.org/ntsb-findings/01035610/cases.md) - [Maintenance: repair](https://openairdocs.org/ntsb-findings/02062015): Personnel issues › Task performance · Maintenance personnel (probable cause); cases with it: [Pilatus PC-12/45, 1 case](https://openairdocs.org/ntsb-findings/02062015/cases.md?model=7090551), [All aircraft, 99 cases](https://openairdocs.org/ntsb-findings/02062015/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Enroute-climb to cruise: Aircraft structural failure](https://openairdocs.org/ntsb-events/337) (defining event); cases with it: [Pilatus PC-12/45, 1 case](https://openairdocs.org/ntsb-events/337/sequence.md?model=7090551), [All aircraft, 290 cases](https://openairdocs.org/ntsb-events/337/sequence.md) ## Analysis During the climb to cruise altitude on a cross-country flight, the pilot heard a loud bang and the pilot's side windshield shattered and the cabin began depressurizing. The pilot returned to the departure airport and landed uneventfully, where he noticed that the seal was extruded in two places around the outer pane. The windshield was sent to the manufacturer for a detailed examination, which revealed that 80% of the fiberglass straps were missing, and they were likely removed by maintenance personnel. A combination of missing straps and heavy delamination caused the outboard ply to become detached from the edge attachment. Moisture ingress at the bottom aft edge caused delamination and arcing. There was no record in the airframe logbook of the straps’ removal. ## Factual narrative On March 24, 2019, about 1101 eastern daylight time, a Pilatus PC-12/45, N944BT, was substantially damaged when the pilot's windshield shattered while flying near Fort Lauderdale, Florida. The commercial pilot and two passengers were not injured. Visual meteorological conditions prevailed, and an instrument flight plan was filed for the flight that originated from the Fort Lauderdale Executive Airport (FXE), Fort Lauderdale, Florida, and was destined for Moore-Murrell Airport (MOR), Morristown, Tennessee. The personal flight was conducted under the provisions of Title 14 Code of Federal Regulations Part 91. According to the pilot, he was climbing through 20,000 ft when he heard a loud bang and the pilot-side windshield shattered. He immediately notified air traffic control that he was returning to FXE and needed to descend. After landing uneventfully, he examined the windshield and noticed that the seal was extruded in two places around the outer pane. Examination of the airplane by a Federal Aviation Administration (FAA) inspector revealed that the pilot-side windshield was shattered but was still attached to the airplane. The bottom left corner and upper corner of the windshield were pushed outward, and the seal around the windshield was torn. The lower left heating element was burnt. The windshield was sent to the manufacturer for further examination. The examination revealed that about 80% of the fiberglass straps were missing and had been removed by maintenance personnel. The missing straps caused the outboard ply to become detached from the edge attachment. Moisture was then able to ingress the bottom aft edge causing delamination and then allowing arcing to occur. Investigators were unable to determine when these straps were removed, as there was no record of this maintenance in the airframe logbooks. The Pilatus Windows Inspection Check referred to the PPG service information letter which states specifically the straps should not be removed, rather repaired following their prescribed maintenance plan. The pilot held a commercial pilot certificate with ratings for airplane single-engine land, single-engine sea, and multi-engine land. His most recent FAA third-class medical certificate was issued on November 15, 2017. He reported 9,000 total hours of flight experience, of which 2,600 hours were in the PC-12. The airplane was manufactured in 2002. It was powered by a Pratt and Whitney PT6A-67, 1,250-horsepower engine, equipped with a four-bladed Hartzell propeller. Its most recent annual inspection was completed on January 15, 2019. ## Aircraft - Registration: [N944BT](https://openairdocs.org/aircraft/N944BT), registered now, S/N 468, built 2002 (OpenAirDocs) - Reported make and model: Pilatus PC12 (45) - Registry model: [Pilatus PC-12/45](https://openairdocs.org/model/pilatus-pc-12-45) (registry code 7090551) (OpenAirDocs) - Registry engine: [Pratt & Whitney Canada PT6A-67B](https://openairdocs.org/engine/pratt-whitney-canada-pt6a-67b) (registry code 52158, turbo-prop) (OpenAirDocs) - Category: Airplane - Serial number: 468 - Year built: 2002 - Airframe hours: 2558 - Engines: Pratt & Whitney Canada PT6A-67B 1250 horsepower turbo prop - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Annual, January 15, 2019, 10 hours before - Departed: FXE, Fort Lauderdale, FL - Destination: KMOR, Morristown, TN - Flight plan: IFR - Equipment: Onboard weather, Stall warning system, ADS-B, Angle of attack indicator, Electronic multifunction display, Electronic primary flight display ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 73; injuries: none; commercial, flight instructor; airplane ratings: single-engine sea, multi-engine land, single-engine land; instrument ratings: airplane; medical: class 3, without waivers/limitations; last flight review May 23, 2018; seat: left; restraint: 3-point; flight hours: 9,000 total, 2,600 in this make and model, 9,000 as pilot in command, 30 in the last 90 days, 30 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 10 statute miles - Temperature: 75 °F, dew point 61 °F - Altimeter: 30.10 inHg - Observed at: FXE, 8 nm away ## 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 20190324001959A](https://openairdocs.org/incident/20190324001959A), Mar 24, 2019: Pilatus PC-12/45, Fort Lauderdale, FL, Minor damage. Aircraft departed fxe on 02/24/2019 enroute to morristown, TN (mor). Pilot started climb to 26,000 feet. At or about 20,000 feet, pilot heard loud noise. The… ## Docket (8 files) The files NTSB released with the investigation on October 15, 2019, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=99173. 6.6 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 1.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40476758&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Pilot's Statement (item 2, .PDF, 70 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40476759&FileExtension=.PDF&FileName=Pilot%27s%20Statement-Master.PDF - FAA Inspector's Statement (item 3, .PDF, 182 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40476760&FileExtension=.PDF&FileName=FAA%20Inspector%27s%20Statement-Master.PDF - Manufacturer's Report (item 4, .PDF, 1.0 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40476761&FileExtension=.PDF&FileName=Manufacturer%27s%20Report-Master.PDF - Pilatus AMM (item 5, .PDF, 1.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40476762&FileExtension=.PDF&FileName=Pilatus%20AMM-Master.PDF - Ppg sil (item 6, .PDF, 1.7 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40476763&FileExtension=.PDF&FileName=PPG%20SIL-Master.PDF - Investigative Photos (item 7, .PDF, 3 photos, 893 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40476764&FileExtension=.PDF&FileName=Investigative%20Photos-Master.PDF - Statement of Party Representatives to NTSB Investigation (item 8, .PDF, 98 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40476765&FileExtension=.PDF&FileName=Statement%20of%20Party%20Representatives%20to%20NTSB%20Investigation-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.