Beech E90 incident near Eau Claire, Wisconsin, December 11, 2013
On December 11, 2013 at about 4:08 pm local time, a 1993 Beech E90, registered N60BA, suffered minor damage in an incident during enroute (cruise) near Eau Claire, Wisconsin. It was flown under charter and air-taxi rules (Part 135). No one was hurt; 2 people were on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The failure of the copilot’s windshield inner layer due to a peel chip that developed as a result of mechanical and thermal expansion stresses.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- December 11, 2013 · about 4:08 pm local time
- Place
- Eau Claire, Wisconsin · map
- Type
- Incident
- Injuries
- No one was hurt; 2 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Beech E90 NO SERIES, built 1993 · all E90s on the register
- Registration
- N60BA · registry record · serial LW-79
- Damage
- Minor damage
- Flight
- Flight · charter and air-taxi rules (Part 135)
The NTSB's narrative final · quoted from the NTSB record
The operator reported that, while in cruise flight at flight level 190, the copilot's inner layer windshield cracked. Windshield heat was not being used at the time, and pressurization was not compromised. The pilot conducted a precautionary landing without incident. Examinations of the windshield revealed that the inner glass ply had fractured due to a peel adhesion chip at the windshield's lower forward corner. The peel chip developed as a result of the differences in coefficient of expansion between the inboard glass ply and vinyl interlayer and had propagated due to mechanical and thermal expansion stresses until the center tension of the thermally tempered glass was penetrated, which caused a spontaneous fracture. The windshield was redesigned in 2001 to reduce the thermal expansion stresses.
The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.
The factual record from the NTSB's investigation tables, in plain English
What happened, in order
- Aircraft structural failure during enroute (cruise) defining event
The NTSB's findings
- cause Aircraft › Aircraft structures › Windows › windshield system › Flight compartment windows › Failure
Pilot
- Certificate: airline transport pilot, commercial pilot
- Ratings: multi-engine land; single-engine land; instrument: airplane
- Flight time: 7,418 hours in all; 2,200 in this make and model
- Last flight review: September 17, 2013
- Medical certificate: Class 2 (with waivers/limitations)
- Seat: left
- Injury: no injuries
The aircraft
- Airframe total time: 9,283 hours
- Last inspection: continuous airworthiness programme, April 20, 2013; 158 hours since
- Maximum gross weight: 10,099 lb
- Landing gear: retractable
- Engine 1: Pratt & Whitney Canada PT6A-28 (turboprop); 9,286 hours total
- Engine 2: Pratt & Whitney Canada PT6A-28 (turboprop); 8,741 hours total
- Operator: Bemidji Aviation Services, Inc.
The flight
- Departed from: KPKD Park Rapids MN
- Destination: KPWK Wheeling IL
- Flight plan: IFR
Weather at the time
- Light: daylight
- Wind: from 280° at 7 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: -9°F (-23°C), dew point -15°F (-26°C)
- Altimeter: 30.44 inHg
- Observation at 3:56 pm from KEAU
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 | |||
| Passengers | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
The docket, the folder of records gathered during an investigation (maintenance records, photographs, witness statements, examinations), has not been read from the NTSB for this case yet; the list appears here once it has. Open the docket at the NTSB.
Everything on this page comes from the NTSB's public records. The narrative, probable cause and findings are the NTSB's own words; the coded tables behind the report are written out in plain English, with pilots' ages, home towns and medical details left out. The documents and photographs are the NTSB's docket, shown as the NTSB released them. This site's own text never names anyone involved. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.