Lancair LC41-550FG accident near Carbondale, Illinois, March 11, 2011
On March 11, 2011 at about 6:07 pm local time, a 2004 Lancair LC41-550FG, registered N521RT, was substantially damaged in an accident during enroute (cruise) near Carbondale, Illinois. It was a business flight under general aviation rules (Part 91). No one was hurt; 1 person was on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The fatigue fracture and subsequent failure of the No. 2 cylinder exhaust valve during cruise flight, which resulted in a 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
- March 11, 2011 · about 6:07 pm local time
- Place
- Carbondale, Illinois · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Lancair LC41-550FG, built 2004
- Registration
- N521RT · registry record · serial 41030
- Damage
- Substantial damage
- Flight
- Business flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The pilot reported that, during cruise flight, the airplane experienced a momentary loss of engine power. While diverting to the nearest airport and completing the emergency checklist items, the engine lost total power, and the pilot chose to make a forced landing to a nearby field. During the landing roll, the airplane's right wing struck a power utility pole before the airplane impacted a ditch and came to rest in a nose-low attitude. A postaccident engine examination revealed that the piston for the No. 2 cylinder had fractured into numerous pieces. Additionally, the exhaust valve head for the No. 2 cylinder had fractured perpendicular to the stem direction where the valve protrudes into the cylinder head during normal operation. The fracture surface of the exhaust valve stem exhibited a series of crack arrest marks consistent with a fatigue crack propagation. Oxidization of the fracture surface was consistent with prolonged exposure to a combustion environment. The fatigue fracture was likely due to extreme temperature gradients experienced along the exhaust valve in the area above the valve seat. A review of available flight data established that the engine had been operated in a manner consistent with the pilot operating handbook. However, without a complete historical flight data record, it was not possible to determine if the engine had been operated outside of its normal operating limits at some point since its original manufacture.
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
- Powerplant sys/comp malf/fail during enroute (cruise)
- Loss of engine power (total) during enroute (cruise) defining event
- Off-field or emergency landing during landing
- Collision with terrain or object (not controlled flight into terrain) during landing (landing roll)
The NTSB's findings
- cause Aircraft › Aircraft power plant › Engine (reciprocating) › Recip eng cyl section › Fatigue/wear/corrosion
- cause Aircraft › Aircraft power plant › Engine (reciprocating) › Recip eng cyl section › Failure
Pilot
- Certificate: private
- Ratings: single-engine land; instrument: airplane
- Flight time: 192 hours in all; 74 in this make and model; 11 in the last 90 days; 5 in the last 30 days; 147 as pilot in command; 0 on instruments
- Last flight review: June 24, 2010
- Medical certificate: Class 3 (without waivers/limitations)
- Seat: left
- Injury: no injuries
The aircraft
- Airframe total time: 501 hours
- Last inspection: annual inspection, March 1, 2010; 241 hours since
- Maximum gross weight: 3,600 lb
- Seats: 4
- Landing gear: fixed
- Engine: Teledyne Continental Motors TSIO-550-C (piston); 501 hours total
- Operator: Robertson Contractors, Inc.
The flight
- Departed from: EYE Indianapolis IN at 4:49 pm
- Destination: POF Poplar Bluff MO
- Flight plan: IFR
Weather at the time
- Light: daylight
- Wind: at 6 knots
- Visibility: 10 statute miles
- Sky: scat at 25,000 ft
- Temperature: 50°F (10°C), dew point 30°F (-1°C)
- Altimeter: 30.19 inHg
- Observation at 5:52 pm from MDH, 5 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 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.