Consolidated Aeronautics INC LAKE MODEL 250 accident near Middle Grove, New York, August 27, 2013
On August 27, 2013 at about 7:19 pm local time, a Consolidated Aeronautics INC LAKE MODEL 250, registered N522WB, was substantially damaged in an accident during initial climb near Middle Grove, New York. It was a personal flight under general aviation rules (Part 91). 1 person had minor injuries. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
Maintenance personnel’s application of insufficient torque to the No. 6 cylinder connecting rod bolts during overhaul, which resulted in the fatigue fracture of the connecting rod and a subsequent total loss of engine power.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- August 27, 2013 · about 7:19 pm local time
- Place
- Middle Grove, New York · map
- Type
- Accident
- Injuries
- 1 person had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft
- Consolidated Aeronautics INC LAKE MODEL 250
- Registration
- N522WB · no longer on the register · serial 56
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The pilot stated that, shortly after takeoff, the engine experienced uncommanded rpm changes, so he turned the airplane to return to the departure airport. He then heard a "loud bang" and the engine running roughly, and it subsequently lost power. When the pilot realized that he would be unable to land at the airport, he maneuvered the airplane for a gear-up forced landing in a field. With only 1/4 of the length of the field remaining, he intentionally yawed the airplane right to avoid obstructions ahead; the airplane came to rest upright with the engine displaced to the left. Oil was covering the engine pylon, the top portion of the empennage, and the leading edges of the vertical and horizontal stabilizers. Postaccident examination of the engine revealed a hole in the crankcase adjacent to the No. 6 cylinder. The No. 6 cylinder connecting rod was fractured and separated from the crankshaft, and one nut from the No. 6 cylinder connecting rod bolt was not present and was found inside the oil sump. Metallurgical examination of the components of the No. 6 cylinder connecting rod revealed that the connecting rod was fractured through one side of the strap at the crankshaft end of the connecting rod and that the strap segment on the other side of the connecting rod was deformed inward. The fractured strap exhibited fatigue cracks from multiple origins, and the split line face on the deformed segment of the strap exhibited fretting damage. The connecting rod likely fractured due to insufficient clamping force across the split line at the crankshaft end of the connecting rod. Although the No. 6 cylinder had been removed about 110 hours before the accident flight, the work performed at that time was not associated with the No. 6 cylinder connecting rod. Therefore, given that the engine was overhauled only about 153 hours before the accident flight, it is likely that insufficient torque was applied to the connecting rod nut during the overhaul.
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
- Loss of engine power (total) during initial climb defining event
- Off-field or emergency landing during emergency descent
- Hard landing during landing (flare/touchdown)
The NTSB's findings
- cause Aircraft › Aircraft power plant › Engine (reciprocating) › Recip engine power section › Fatigue/wear/corrosion
- cause Aircraft › Aircraft power plant › Engine (reciprocating) › Recip engine power section › Incorrect service/maintenance
- cause Personnel issues › Task performance › Maintenance › (general) › Maintenance personnel
Pilot
- Certificate: private
- Ratings: multi-engine sea; single-engine land; single-engine sea; instrument: airplane
- Flight time: 3,585 hours in all; 585 in this make and model; 27.7 in the last 90 days; 14.8 in the last 30 days; 3,500 as pilot in command
- Last flight review: March 20, 2012
- Medical certificate: Class 3 (with waivers/limitations)
- Seat: left
- Injury: minor injuries
The aircraft
- Airframe total time: 2,812 hours
- Last inspection: annual inspection, June 21, 2013; 12 hours since
- Maximum gross weight: 3,140 lb
- Seats: 4
- Landing gear: fixed
- Engine: Lycoming IO-540-C4B5 (piston); 0 hours total
The flight
- Departed from: 5B2 Saratoga Spring NY at 7:12 pm
- Destination: None Indian Lake NY
- Flight plan: none
Weather at the time
- Light: daylight
- Wind: from 310° at 4 knots
- Visibility: 10 statute miles
- Sky: broken clouds at 5,000 ft; scat at 4,400 ft
- Temperature: 81°F (27°C), dew point 64°F (18°C)
- Altimeter: 29.88 inHg
- Observation at 7:50 pm from SCH, 14 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
17 documents, released by the NTSB on November 26, 2014. 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.
The same docket at the NTSB · documents without a copy here are fetched from the NTSB when you open them.
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.