Cessna 340A accident near Middleton, Wisconsin, May 30, 2007
On May 30, 2007 at about 8:50 pm local time, a Cessna 340A, registered N17MH, was substantially damaged in an accident near Middleton, Wisconsin (Middleton Municipal Airport). It was an instructional flight 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
Failure of the right main landing gear extension and retraction linkage, which allowed the gear assembly to collapse during landing rollout. An additional cause was the improper adjustment procedure(s) by undetermined mechanic(s). The runway lights struck during the accident sequence were contributing factors.
Source: NTSB aviation accident database, copy made October 4, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- May 30, 2007 · about 8:50 pm local time
- Place
- Middleton, Wisconsin · Middleton Municipal Airport
- Type
- Accident
- Injuries
- No one was hurt; 2 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Cessna 340A · all 340As on the register
- Registration
- N17MH · registry record · serial 340A-0797
- Damage
- Substantial damage
- Flight
- Instructional flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The pilot stated that multiple approaches and landings had been conducted during the dual proficiency flight. Prior to the accident landing, he observed three green lights indicating that the landing gear was properly extended. The landing touchdown was "light." A "few seconds" after touchdown the aircraft began to "shudder" and the gear horn started to sound. The airplane began to drift right and the right wing began to settle. As the right main gear collapsed, the aircraft departed the runway pavement, striking two runway lights in the process. The aircraft came to rest in a grass area adjacent to the runway. The nose and left main landing gear remained extended during the accident. A post accident examination of the aircraft revealed that the forward bellcrank attachment flange on the landing gear strut failed. In addition, the lower flange on the bellcrank had also failed. According to the airplane manufacturer, the location of the failures was consistent with the cumulative effect of improper adjustment of the downlock mechanism over time. However, any improper adjustment procedure could not be attributed to any specific maintenance action or to a particular mechanic. Additionally, the maintenance log entry related to the adjustments made during the most recent annual inspection indicated that the airplane maintenance manual instructions regarding landing gear adjustments were complied with properly.
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
Pilot
- Certificate: private
- Ratings: multi-engine land; single-engine land; instrument: airplane
- Flight time: 500 hours in all; 88 in this make and model; 6 in the last 90 days; 2 in the last 30 days; 389 as pilot in command
- Last flight review: August 1, 2007
- Medical certificate: Class 3 (with waivers/limitations)
- Seat: left
- Injury: no injuries
Flight instructor
- Certificate: flight instructor, commercial pilot
- Ratings: multi-engine land; single-engine land; instructor: airplane multi-engine; instructor: airplane single-engine; instructor: instrument airplane; instrument: airplane; rotorcraft: glider
- Flight time: 9,950 hours in all; 400 in this make and model; 161 in the last 90 days; 65 in the last 30 days; 9,680 as pilot in command; 7,692 on instruments
- Last flight review: January 1, 2007
- Medical certificate: Class 2 (with waivers/limitations)
- Seat: rgt
- Injury: no injuries
The aircraft
- Airframe total time: 4,575 hours
- Last inspection: annual inspection, January 1, 2007
- Maximum gross weight: 6,430 lb
- Seats: 6
- Landing gear: retractable
- Engine 1: Teledyne Continental TSIO-520-NB (piston); 0 hours total
- Engine 2: Teledyne Continental TSIO-520-NB (piston); 0 hours total
The flight
- Departed from: MSN Madison WI at 8:40 pm
- Destination: C29 Middleton WI
- Flight plan: none
- Runway 28, 4,000 ft by 150 ft
- A second pilot was aboard
Weather at the time
- Light: daylight
- Wind: from 180° at 11 knots, gusting 17
- Visibility: 6 statute miles
- Sky: broken clouds at 4,500 ft
- Temperature: 81°F (27°C), dew point 57°F (14°C)
- Altimeter: 30.01 inHg
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 2 |
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.
About this page
Everything above comes from the NTSB's public accident database: the narrative, probable cause and findings are the NTSB's own words, and the coded tables behind its report (pilot, aircraft, flight, weather, injuries, sequence of events) are written out in plain English. Pilots' ages, home towns and medical details are left out on purpose. The documents and photographs are the NTSB's docket, the folder of records gathered during the investigation, shown as the NTSB released them (the NTSB redacts some personal details first) and listed under the NTSB's own titles. This site's own text never names pilots, passengers or anyone else involved. A preliminary report describes what is known soon after the event and can change; the final report, with the probable cause, usually follows one to two years later and this page is refreshed when it does. Case number CHI07LA159.