Moravan Zlin 50LX accident near Modesto, California, May 10, 2008
On May 10, 2008 at about 8:00 pm local time, a Moravan Zlin 50LX, registered N6660K, was substantially damaged in an accident during maneuvering (low-alt flying) near Modesto, California (Modesto City-Cty Airport). It was an air show or air race flight under general aviation rules (Part 91). 1 person was seriously injured. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The pilot failed to maintain clearance from terrain during a low-altitude maneuver at an airshow. Contributing to the accident was the task overload in the increased frequency congestion.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- May 10, 2008 · about 8:00 pm local time
- Place
- Modesto, California · Modesto City-Cty Airport · map
- Type
- Accident
- Injuries
- 1 person was seriously injured.
- Weather
- visual conditions (good weather)
- Aircraft
- Moravan Zlin 50LX
- Registration
- N6660K · no longer on the register · serial 075
- Damage
- Substantial damage
- Flight
- Air show or air race flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The pilot was performing in an airshow that was conducted at a controlled airport serviced by airlines. Two Federal Aviation Administration (FAA) inspectors acting as the FAA monitors, witnessed the accident. Performances, as a rule, are timed so that they do not conflict with inbound and landing airline traffic. If there is a timing conflict, normally the show is temporarily stopped so as not to delay the airline traffic. During the accident pilot's performance, the pilot was transmitting directly to the crowd, as well as communicating with an on ground safety observer, the airshow waiver holder, and an air traffic control tower controller. The air traffic control tower controller advised the pilot to stop the performance due to an inbound arriving airliner and make a right base entry for landing. The pilot had completed a normal sequence and then requested to make one more pass and the tower controller approved the request. The pilot then added the additional maneuver as his final routine before exiting the performance box. The FAA inspector indicated that during the added maneuver, the right wing impacted the ground. The pilot stated that during the airshow briefing, he had requested a sterile frequency for maintaining communication with airshow and ground support staff, which he indicated was standard operating procedures at other airshows. The air traffic control tower personnel elected to have the airshow pilots monitoring and communicating on the same frequency as the tower controllers. The pilot stated that during the flight, he was interrupted numerous times by tower personnel and incoming aircraft, which prevented his ground safety observer from communicating with him and not only added to his workload, but affected his concentration during the maneuver.
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
- Low altitude operation/event during maneuvering (aerobatics)
- Collision with terrain or object (not controlled flight into terrain) during maneuvering (low-alt flying) defining event
The NTSB's findings
- cause Aircraft › Aircraft oper/perf/capability › Performance/control parameters › (general) › Not attained/maintained
- factor Personnel issues › Task performance › Workload management › Task overload › Pilot
- cause Personnel issues › Action/decision › Action › Incorrect action performance › Pilot
Pilot
- Certificate: commercial pilot
- Ratings: single-engine land; instrument: airplane
- Flight time: 4,000 hours in all; 1,500 in this make and model; 30 in the last 90 days; 15 in the last 30 days
- Last flight review: September 4, 2007
- Medical certificate: Class 2 (without waivers/limitations)
- Seat: sngl
- Injury: serious injuries
The aircraft
- Airframe total time: 1,111 hours
- Last inspection: condition inspection, April 12, 2008; 8 hours since
- Maximum gross weight: 1,675 lb
- Seats: 1
- Landing gear: fixed
- Engine: Textron Lycoming IO-540 (piston); 0 hours total
The flight
- Departed from: KMOD Modesto CA at 7:45 pm
- Destination: KMOD Modesto CA
- Flight plan: none
- Runway 28R, 5,911 ft by 150 ft
Weather at the time
- Light: daylight
- Wind: from 310° at 3 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 81°F (27°C), dew point 43°F (6°C)
- Altimeter: 29.97 inHg
- Observation at 9:11 pm from MOD
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.