# NTSB FTW95FA004: Beech 1900D, N31YV, Denver, CO, October 2, 1994 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Field investigation · Final report - Date: October 1, 1994, 18:05 local (Oct 2, 1994, 00:05 UTC) - Place: Denver, CO - Coordinates: 39.760807, -104.920593 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=39.7608&lon=-104.9206&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: Minor injuries - Injuries: 1 minor, 17 uninjured - Status: Completed, report May 18, 1995 - Report: Approved by Office Director - NTSB case key (mKey): 19190 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=FTW95FA004 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/19190/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=19190 - Page: https://openairdocs.org/ntsb/FTW95FA004 ## Probable cause THE CAPTAIN'S INACCURATE EVALUATION OF WEATHER CONDITIONS, AND HIS DECISION TO FLY INTO KNOWN ADVERSE WEATHER. A FACTOR WAS THE HAIL. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - In flight encounter with weather, climb - to cruise - weather evaluation - inaccurate, pilot in command (cause) - flight into known adverse weather - initiated, pilot in command (cause) - weather condition - hail (contributing factor) - Airframe/component/system failure/malfunction, climb - to cruise - window,flight compartment window/windshield - disintegrated ## Analysis AS THE LEVEL 6 THUNDERSTORM PASSED OVER THE AIRPORT FROM NORTHWEST TO SOUTHEAST, THE CAPTAIN ELECTED NOT TO TAKE OFF BECAUSE OF THE FALLING HAIL. AFTER WAITING ABOUT 30 MINUTES, THE FLIGHT TOOK OFF ON RUNWAY 35L. THE CAPTAIN REQUESTED A RIGHT TURN, AND WAS ASSIGNED A HEADING OF 080 DEGREES AND CLEARED TO CLIMB TO 20,000 FEET. THE AIRPLANE ENTERED THE OVERCAST AND ENCOUNTERED 'LIGHT HAIL.' AS IT TURNED ONTO ITS ASSIGNED HEADING, THE AIRBORNE WEATHER RADAR INDICATED HEAVY PRECIPITATION AHEAD. A REQUEST WAS MADE FOR A TURN FURTHER RIGHT. SUDDENLY, THE RIGHT WINDSHIELD SHATTERED, SENDING GLASS PARTICLES INTO THE FIRST OFFICER'S EYES. THE AIRPLANE IMMEDIATELY DESCENDED TO VISUAL METEOROLOGICAL CONDITIONS, RETURNED TO THE AIRPORT, AND LANDED. ## Factual narrative HISTORY OF FLIGHT On October 1, 1994, approximately 1805 mountain daylight time, a Beech 1900D, N31YV, was substantially damaged during an inflight encounter with adverse weather near Denver, Colorado. There were no injuries to the captain and 16 passengers, but the first officer sustained minor injuries. Instrument meteorological conditions prevailed. The following is based on interviews with the captain and first officer, and the pilot/operator report. The airplane, flight 7658, operated by Mesa Airlines, Inc., d/b/a United Express, taxied to runway 35L at 1720, but was placed in the "penalty box" due to weather causing a traffic backlog. It began to rain heavily and several wind shear alerts were issued. When the flight was cleared to taxi onto the runway, the captain declined and decided to wait for better weather conditions. Hail began to fall and the right engine was shut down to conserve fuel. A Boeing 727, later identified as United Air Lines flight 898, took off at 1748 and turned to the left. Shortly thereafter, at 1750, the United pilot advised the control tower that traffic should avoid a westerly departure. The captain said the pilot sounded "thoroughly shaken." When weather conditions improved and the crew noted no precipitation echoes on the weather radar through various tilt angles, flight 7658 took off at 1759. Because of the previous pilot report, the captain requested a right turn after departure. The flight was assigned a heading of 080 degrees and an altitude of 20,000 feet. The airplane entered the overcast and it began to rain, followed by "light hail." As the airplane was approaching 10,000 feet, the airborne weather radar indicated heavy precipitation ahead, and the crew requested a turn further to the right. The airplane then encountered heavy hail and the right windshield "exploded," sending glass particles into the first officer's eyes and temporarily blinding him. After telling air traffic control what had happened, the flight was cleared to land on any runway. The captain descended into visual meteorological conditions and landed on runway 26R. METEOROLOGICAL INFORMATION The captain said that he personally obtained a weather briefing via computer prior to departure. The reports indicated that visual meteorological conditions prevailed in Denver, Amarillo, and along the route. He said the weather reports were not "real time," but were probably at least one hour or more old. Asked why his dispatcher did not provide him with more timely weather information, the captain replied that his company operated under Federal Aviation Regulations Part 135 and did not have a dispatch office. Obtaining weather reports and filing flight plans was done by the flight crew. Weather and air traffic control studies were made by the Safety Board's Operational Factors Division. These reports are attached as exhibits. FLIGHT RECORDERS Both cockpit voice and flight data recorders were removed from the airplane and were examined by the Safety Board's Engineering and Computer Services Division. No extraordinary data was retrieved from the flight data recorder. The ATC communications channel on the cockpit voice recorder was found to have been wired incorrectly when it was installed by the airplane manufacturer. No cockpit communications transcript was made. ## Aircraft - Registration: [N31YV](https://openairdocs.org/deregistered/N31YV-1999-08-02), registration cancelled 1999-08-02, S/N UE-31 (OpenAirDocs) - Reported make and model: BEECH 1900D - Registry model: [Beech 1900D](https://openairdocs.org/model/beech-1900d) (registry code 1154162) (OpenAirDocs) - Category: Airplane - Serial number: UE-31 - Airframe hours: 4723 - Engines: P&W PT6A-67D turbo prop - Damage: Substantial damage - Flight: Part 135 - Registered owner: Mesa Airlines, Inc. - Airworthiness certificate: Standard, Transport - Last inspection: Continuous airworthiness, September 26, 1994, 44 hours before - Departed: DEN, CO - Destination: AMA, AMARILLO, TX - Flight plan: IFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 35; commercial, airline transport; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; seat: left; flight hours: 6,921 total, 1,859 in this make and model, 4,786 as pilot in command, 266 in the last 90 days, 96 in the last 30 days, 8 in the last 24 hours ## Weather - Conditions: Instrument (IMC), Day - Wind: 310° at 23 knots, gusting 35 - Visibility: 1 statute miles - Lowest ceiling: 1,300 ft overcast - Temperature: 55 °F, dew point 54 °F - Altimeter: 29.00 inHg - Observed at: DEN, 9 nm away ## Docket (5 files) The files NTSB released with the investigation on June 6, 1995, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=19190. 3.5 MB in all. - Supplement E (item 1, .PDF, 97 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40386099&FileExtension=.PDF&FileName=Supplement%20E-Redacted.PDF - Supplement S (item 2, .PDF, 35 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40020819&FileExtension=.PDF&FileName=Supplement%20S-Master.PDF - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1/2 (item 3, .PDF, 2.6 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40386100&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1%2F2-Redacted.PDF - ATC Report (item 4, .PDF, 66 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40386101&FileExtension=.PDF&FileName=ATC%20Report-Redacted.PDF - Weather Report (item 5, .PDF, 740 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40386102&FileExtension=.PDF&FileName=Weather%20Report-Redacted.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.