Amateur-built RV-4 and amateur-built VANS RV-8 mid-air collision near Madera, California, October 11, 2011
On October 11, 2011 at about 6:15 pm local time, 2 aircraft, amateur-built RV-4 (N506DC) and amateur-built VANS RV-8 (N427EF), were involved in a mid-air collision near Madera, California (Fresno airport). 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 third airplane pilot’s failure to maintain visual contact with the second airplane during the formation flight.
The third airplane pilot’s failure to maintain visual contact with the second airplane during the formation flight.
Source: NTSB aviation accident database, copy made November 2, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- October 11, 2011 · about 6:15 pm local time · cases in 2011
- Place
- Madera, California · Fresno · cases near this airport · map
- Type
- Accident · mid-air collision
- Injuries
- No one was hurt; 2 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft 1
- Amateur-built RV-4
- Registration
- N506DC · registry record · serial 001
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
- Aircraft 2
- Amateur-built VANS RV-8
- Registration
- N427EF · registry record · serial 80200
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative for the amateur-built RV-4 final · quoted from the NTSB record
The two accident airplanes were part of a three-airplane formation flight comprised of an RV-8 airplane in the lead position, an RV-8 in the second position, and an RV-4 in the third position. The group performed a formation flight briefing prior to flight. Three uneventful formation maneuvers were performed after departure; for the fourth maneuver, the lead pilot made a radio call commanding the group to begin a climbing left turn. All members of the group responded in the affirmative, and the lead pilot pitched his airplane up and began the turn. After a 2-second interval, the second RV-8 pilot began the maneuver, following the first airplane. The RV-4 pilot then began the maneuver and momentarily lost visual contact with the second RV-8. He then made visual contact with the lead airplane but misidentified it as the second RV-8. He then realized he was in error, but, just as he was about to perform evasive maneuvers, his airplane struck the second RV-8. The RV-4 sustained substantial damage to the aft fuselage, and the left wing tip and aileron partially separated from the airplane after making contact with the propeller of the RV-8. The pilot reported that the airplane began a 4,000-foot-per-minute spiraling descent and did not respond to aileron control inputs. He regained control of the airplane utilizing rudder, elevator, and throttle control, and subsequently performed a forced landing into a field. The RV-8 sustained substantial damage to the outboard section of the right wing leading edge and returned to the departure airport uneventfully. Both pilots reported no preimpact mechanical malfunctions or failures with the airframe or engine that would have precluded normal operation.
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 NTSB's narrative for the amateur-built VANS RV-8 final · quoted from the NTSB record
The two accident airplanes were part of a three-airplane formation flight comprised of an RV-8 airplane in the lead position, an RV-8 in the second position, and an RV-4 in the third position. The group performed a formation flight briefing prior to flight. Three uneventful formation maneuvers were performed after departure; for the fourth maneuver, the lead pilot made a radio call commanding the group to begin a climbing left turn. All members of the group responded in the affirmative, and the lead pilot pitched his airplane up and began the turn. After a 2-second interval, the second RV-8 pilot began the maneuver, following the first airplane. The RV-4 pilot then began the maneuver and momentarily lost visual contact with the second RV-8. He then made visual contact with the lead airplane but misidentified it as the second RV-8. He then realized he was in error, but, just as he was about to perform evasive maneuvers, his airplane struck the second RV-8. The RV-4 sustained substantial damage to the aft fuselage, and the left wing tip and aileron partially separated from the airplane after making contact with the propeller of the RV-8. The pilot reported that the airplane began a 4,000-foot-per-minute spiraling descent and did not respond to aileron control inputs. He regained control of the airplane utilizing rudder, elevator, and throttle control, and subsequently performed a forced landing into a field. The RV-8 sustained substantial damage to the outboard section of the right wing leading edge and returned to the departure airport uneventfully. Both pilots reported no preimpact mechanical malfunctions or failures with the airframe or engine that would have precluded normal operation.
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 for the amateur-built RV-4 from the NTSB's investigation tables, in plain English
What happened, in order
- Midair collision during maneuvering defining event
The NTSB's findings
- cause Personnel issues › Psychological › Attention/monitoring › Monitoring other aircraft › Pilot
- cause Personnel issues › Psychological › Attention/monitoring › Monitoring other aircraft › Pilot of other aircraft
Pilot
- Certificate: commercial pilot
- Ratings: multi-engine land; single-engine land; instructor: airplane single-engine; instrument: airplane
- Flight time: 5,000 hours in all; 600 in this make and model; 35 in the last 90 days
- Last flight review: August 4, 2011
- Medical certificate: Class 2 (with waivers/limitations)
- Seat: frt
- Injury: no injuries
The aircraft
- Airframe total time: 580 hours
- Last inspection: condition inspection, May 6, 2011; 30 hours since
- Maximum gross weight: 1,500 lb
- Seats: 1
- Landing gear: fixed
- Engine: Superior IO 360 (piston); 0 hours total
The flight
- Departed from: E79 Fresno CA at 6:00 pm
- Destination: E79 Fresno CA
- Flight plan: none
Weather at the time
- Light: daylight
- Wind: from 210° at 6 knots
- Visibility: 10 statute miles
- Sky: broken clouds at 11,000 ft; a few clouds at 6,000 ft
- Temperature: 63°F (17°C), dew point 36°F (2°C)
- Altimeter: 29.87 inHg
- Observation at 5:53 pm from KFAT, 20 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 |
The factual record for the amateur-built VANS RV-8 from the NTSB's investigation tables, in plain English
What happened, in order
- Midair collision during maneuvering defining event
The NTSB's findings
- cause Personnel issues › Psychological › Attention/monitoring › Monitoring other aircraft › Pilot of other aircraft
- cause Personnel issues › Psychological › Attention/monitoring › Monitoring other person › Pilot
Pilot
- Certificate: private
- Ratings: single-engine land; instrument: airplane
- Flight time: 4,000 hours in all; 400 in this make and model; 30 in the last 90 days; 15 in the last 30 days
- Last flight review: January 3, 2010
- Medical certificate: Class 3 (without waivers/limitations)
- Seat: frt
- Injury: no injuries
The aircraft
- Airframe total time: 400 hours
- Last inspection: condition inspection, October 5, 2010; 5 hours since
- Maximum gross weight: 1,600 lb
- Seats: 2
- Landing gear: fixed
- Engine: Lycoming IO 360 (piston); 0 hours total
The flight
- Departed from: E79 Fresno CA at 6:00 pm
- Destination: E79 Madera CA
- Flight plan: none
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
The NTSB has not released the docket for this case yet. The docket, the folder of records gathered during an investigation (maintenance records, photographs, witness statements, examinations), is usually released when the investigation is nearly complete, and the list here is refreshed when it appears. Check at the NTSB.
Connections how this case links to the rest of the register
Aircraft
- N506DC on the register today · the tail number may have moved to another aircraft since
- N427EF on the register today · the tail number may have moved to another aircraft since
- Engine: Superior IO 360 202 aircraft carry this series today · as the NTSB recorded it
- Engine: Lycoming IO 360 8,559 aircraft carry this series today · as the NTSB recorded it
Place
- Sierra Sky Park Airport · nearest airport
- Accidents and incidents in California 9,080 since 1982 · 1,098 in the last ten years
- California 27,686 aircraft registered
The whole map of how records connect · these connections as data: /graph/accident/WPR12CA005.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.