Extra Flugzeugbau 300S accident near Dow, Illinois, March 24, 1999
On March 24, 1999 at about 7:00 pm local time, a Extra Flugzeugbau 300S, registered N9K, was substantially damaged in an accident near Dow, 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
a fatigue failure of the upper left longeron and adjacent diagonal cross member near the horizontal stabilizer attach point. A factor related to the accident was that the manufacturer informed the operator that they were already in compliance with the latest revision of a service bulletin because they had complied with a previous revision.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- March 24, 1999 · about 7:00 pm local time
- Place
- Dow, Illinois · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Extra Flugzeugbau 300S
- Registration
- N9K · no longer on the register · serial 022
- Damage
- Substantial damage
- Flight
- Business flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The pilot reported hearing a 'bang' as he initiated a left roll at the beginning of an airshow routine practice flight. The pilot landed the airplane uneventfully. Inspection revealed that the upper left longeron and a diagonal cross member in the empennage had failed. Metallurgical examination of the failed components revealed they failed due to fatigue. The aircraft manufacturer (Extra) had issued 3 Service Bulletins 300-2-95, Revision 'A' 'B' and 'C' regarding cracks in this area. Revision 'A' called for inspections of the area. Cracks were found on N9K in 1997 and repairs were made in accordance with Extra instructions. Revision 'B' was then issued calling for the same repairs that the operator had already made if cracks were found. When Revision 'C' was issued it called for the same type of repair, but the gusset to be used was shaped differently and was larger. The operator was told by Extra that if they were in compliance with Revision 'B' they were also considered to be in compliance with Revision 'C.'
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: airline transport pilot, flight instructor
- Ratings: multi-engine land; single-engine land; instructor: airplane multi-engine; instructor: airplane single-engine; instructor: instrument airplane; instrument: airplane
- Flight time: 3,450 hours in all; 682 in this make and model; 82 in the last 90 days; 26 in the last 30 days; 3,390 as pilot in command
- Medical certificate: Class 1 (valid medical--no waivers/lim.)
- Seat: ctr
The aircraft
- Airframe total time: 1,055 hours
- Last inspection: annual inspection, March 15, 1999; 16 hours since
- Maximum gross weight: 1,800 lb
- Seats: 1
- Landing gear: fixed
- Engine: Lycoming AEIO-540 (piston); 0 hours total
The flight
- Departed from: H59 Dow IL at 6:55 pm
- Destination: H59
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 360° at 9 knots
- Visibility: 10 statute miles
- Sky: scat at 4,500 ft
- Temperature: 55°F (13°C), dew point 37°F (3°C)
- Altimeter: 29.00 inHg
- Observation at 6:53 pm from STL, 21 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| 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.
Other NTSB records under N9K the same tail number, which may have belonged to a different aircraft at the time
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.