# NTSB FTW94IA139: Beech 1900C, N141UE, Cheyenne, WY, April 27, 1994 - Type: NTSB incident investigation - Classification: Incident · No injuries · Incident investigation · Final report - Date: April 27, 1994, 08:00 local (14:00 UTC) - Place: Cheyenne, WY - Location: 41.1400° N, 104.8202° W: Placed by OpenAirDocs: center of Cheyenne, WY, within about 6 miles (OpenAirDocs) - Nearby events: https://openairdocs.org/map.md?lat=41.1400&lon=-104.8202&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 21 uninjured - Status: Completed, report December 7, 1994 - Report: Approved by Office Director - NTSB case key (mKey): 18939 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=FTW94IA139 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/18939/pdf - Page: https://openairdocs.org/ntsb/FTW94IA139 ## Probable cause A PARTIAL FAILURE OF THE LEADING EDGE TIP PORTION OF ONE OF THE LEFT ENGINE PROPELLER BLADES DUE TO PREVIOUS IMPACT DAMAGE FROM AN UNKNOWN SOURCE. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Airframe/component/system failure/malfunction, cruise - propeller system/accessories,blade - failure,partial (cause) - reason for occurrence undetermined (cause) ## Analysis WHILE ON A SCHEDULED PASSENGER FLIGHT AT 15,000 FEET MSL, AND WHILE PASSING OVER CHEYENNE, WYOMING, THE AIRCRAFT LOST PART OF A PROPELLER BLADE FROM THE LEFT ENGINE. THE ENGINE WAS SECURED, AND DUE TO INCLEMENT WEATHER IN THE CHEYENNE AREA, THE FLIGHT PROCEEDED TO ITS SCHEDULED DESTINATION IN DENVER, COLORADO, WHERE IT LANDED WITHOUT INCIDENT. THE PROPELLER BLADE WAS REMOVED AND TESTED AT BOTH THE MANUFACTURER'S FACILITIES AND AT THE MATERIALS LABORATORY AT WRIGHT PATTERSON AIR FORCE BASE. THE WRIGHT PATTERSON LABORATORY PROVIDED INFORMATION THAT THERE WAS A PROBABLE NICK OR GOUGE IN THE LEADING EDGE OF THE BLADE AT THE FAILURE POINT. THE SOURCE OF THAT DAMAGE WAS NOT DISCOVERED DURING THE COURSE OF THE INVESTIGATION. ## Factual narrative On April 27, 1994, at 0800 mountain daylight time, a Beech 1900C, N141UE, operating as United Express Flight 5840, sustained minor damage while in cruise flight when a portion of a propeller blade separated from the number one engine. The 2 crew members and 19 passengers were not injured. The flight was on an IFR flight plan and was operating under 14 CFR Part 135 when the incident occurred. The flight departed Bismarck, North Dakota, at 0555 and was in the vicinity of Cheyenne, Wyoming, en route to Denver, Colorado. According to the crew, the flight was at 15,000 feet msl in clear air when the propeller failure occurred. Following the loss, the crew stated they secured the engine and proceeded to Denver due to unfavorable weather for an emergency landing in Cheyenne. The propeller was a Hartzell HC-B4MP-3A/MI0877K. It was removed and shipped to Hartzell for examination. The Hartzell report is attached and provides information that the leading edge tip end of the number three blade separated in a jagged manner and the tip was not recovered. The trailing edge of the blade remained intact almost to the tip; however, the outer shin laminates had separated. No other discrepancies were noted. Following the examination by Hartzell, the failed blade was sent to Wright Patterson Air Force Base for further examination by the composite section of their materials laboratory. The Wright Patterson report is attached and provides information that the blade failed due to apparent impact damage on the leading edge. The source of the impact damage was not discovered. ## Aircraft - Registration: [N141UE](https://openairdocs.org/deregistered/N141UE-2009-04-02), registration cancelled 2009-04-02, S/N UC-141, built 1991 (OpenAirDocs) - Reported make and model: BEECH 1900C - Registry model: [Beech 1900C](https://openairdocs.org/model/beech-1900c) (registry code 1154161) (OpenAirDocs) - Registry engine: [Pratt & Whitney PT6A series](https://openairdocs.org/engine/pratt-whitney-pt6a-series) (registry code 52032, turbo-prop) (OpenAirDocs) - Category: Airplane - Serial number: UC141 - Airframe hours: 6430 - Engines: P&W PT6A-65-B 1100 horsepower turbo prop - Damage: Minor damage - Flight: Part 135 - Registered owner: Great Lakes Aviation, Ltd. - Airworthiness certificate: Standard, Normal - Last inspection: Continuous airworthiness, April 23, 1994, 36 hours before - Departed: BIS, BISMARCK, ND - Destination: DEN, DENVER, CO - Flight plan: IFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 34; flight instructor, airline transport; airplane ratings: multi-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; seat: left; flight hours: 7,718 total, 5,600 in this make and model, 6,903 as pilot in command, 283 in the last 90 days, 100 in the last 30 days, 6 in the last 24 hours ## Weather - Conditions: Instrument (IMC), Day - Wind: 60° at 4 knots - Visibility: 2 statute miles - Lowest ceiling: 1,000 ft overcast - Temperature: 25 °F, dew point 25 °F - Altimeter: 30.00 inHg - Observed at: CYS ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Incident 19940427016589I](https://openairdocs.org/incident/19940427016589I), Apr 27, 1994: Beech 1900C, Denver, CO, Minor damage. Lost part of left propeller in flight. Shut engine down. Diverted to Denver. 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.