Beech E-90 accident near Des Moines, Iowa, February 15, 2011
On February 15, 2011 at about 3:30 pm local time, a Beech E-90, registered N51DN, was substantially damaged in an accident during enroute (climb to cruise) near Des Moines, Iowa. It was a flight test under general aviation rules (Part 91). 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 improper installation of the right aileron by maintenance personnel.
Source: NTSB aviation accident database, copy made November 2, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- February 15, 2011 · about 3:30 pm local time · cases in 2011
- Place
- Des Moines, Iowa · map
- Type
- Accident
- Injuries
- No one was hurt; 2 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Beech E-90 · all E-90s on the register
- Registration
- N51DN · registry record · serial LW-7
- Damage
- Substantial damage
- Flight
- Flight test · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The airplane had recently undergone maintenance, which included an inspection of the ailerons requiring removal, reinstallation, and a functional check. Prior to the test flight, the pilot performed a pre-flight inspection of the airplane and a flight control free and correct check with no anomalies noted. While executing a turn at flight level 180, the right aileron departed the airplane. The airplane landed without further incident. Examination of the airplane revealed the inboard and middle airframe aileron hinge brackets were attached to the aft spar, intact, and showed no visible damage. The outboard airframe aileron hinge bracket was pulled and separated from the aft spar. The aileron was not located. Based on the condition of the hinge brackets, the evidence indicated the aileron bolts were not properly engaged in the aileron nut plates which caused the bolts to fall out and the aileron to depart the airplane.
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
- Part(s) separation from AC during enroute (climb to cruise) defining event
The NTSB's findings
- cause Personnel issues › Task performance › Maintenance › Installation › Maintenance personnel
- cause Aircraft › Aircraft structures › Wing structure › Ailerons › Incorrect service/maintenance other cases naming the airframe structure
Pilot
- Certificate: airline transport pilot, flight instructor, commercial pilot
- Ratings: multi-engine land; single-engine land; instructor: airplane multi-engine; instructor: airplane single-engine; instrument: airplane
- Flight time: 15,449 hours in all; 329 in this make and model; 60 in the last 90 days; 49 in the last 30 days; 13,037 as pilot in command; 1,045 on instruments
- Last flight review: January 26, 2011
- Medical certificate: Class 2 (with waivers/limitations)
- Seat: left
- Injury: no injuries
The aircraft
- Airframe total time: 9,353 hours
- Last inspection: continuous airworthiness programme, February 14, 2011; 0 hours since
- Maximum gross weight: 10,100 lb
- Seats: 8
- Landing gear: retractable
- Engine 1: P&W Canada PT6A-27-28 (turboprop); 0 hours total
- Engine 2: U/A Canada PT6A-27-28 (turboprop); 0 hours total
- Operator: D-W Corporation
The flight
- Departed from: DSM Des Moines IA at 3:00 pm
- Destination: DSM Des Moines IA
- Flight plan: IFR
Weather at the time
- Light: daylight
- Wind: from 170° at 13 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 41°F (5°C), dew point 32°F (0°C)
- Altimeter: 30.03 inHg
- Observation at 2:50 pm from DSM, 45 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 2 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
7 documents, released by the NTSB on May 27, 2011. View them here, or download them; the NTSB redacts some personal details before release, and this site shows the NTSB's own titles rather than its file names.
| # | Document | What it is | |
|---|---|---|---|
| 1 | Pilot/operator Aircraft Accident Report, NTSB Form 6120.1 | PDF, 9 pages | View Download |
| 2 | Pilot Statement | PDF, 5 pages | View Download |
| 3 | Airframe Logbook Entry | PDF, 1 page | View Download |
| 4 | King Air Maintenance Manual Excerpt | PDF, 1 page | View Download |
| 5 | View of Outboard Aileron Hinge | PDF, 1 page | View Download |
| 6 | View of Inboard Aileron Hinge | PDF, 1 page | View Download |
| 7 | View of Aft Right Wing | PDF, 1 page | View Download |
The same docket at the NTSB · documents without a copy here are fetched from the NTSB when you open them.
Connections how this case links to the rest of the register
- N51DN on the register today · the tail number may have moved to another aircraft since
- Beechcraft E-90 King Air E90 146 registered today · the model family and its accident history
- Beechcraft 6 aircraft on the register
- Engine: P&W Canada PT6A-27-28 75 aircraft carry this series today · as the NTSB recorded it
- Engine: U/A Canada PT6A-27-28 75 aircraft carry this series today · as the NTSB recorded it
- Des Moines International · departed from
- Accidents and incidents in Iowa 871 since 1982 · 131 in the last ten years
- Iowa 4,513 aircraft registered
The whole map of how records connect · these connections as data: /graph/accident/CEN11LA192.json.
The bigger picture in Aviation Analytics: accidents over time since 1982, by model, by phase of flight and conditions, by place and on the map.
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 does not name anyone involved, its policy at this time. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.