Amateur-built CHALLENGER II accident near Princeton, Illinois, September 20, 1994
On September 20, 1994 at about 3:00 pm local time, a amateur-built CHALLENGER II (ultralight), registered UNREG, was substantially damaged in an accident near Princeton, Illinois. It was a personal flight under ultralight rules (Part 103). 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
INADEQUATE DIRECTIONAL STABILITY OF THE AIRCRAFT (DUE TO INSTALLATION OF LEXAN COCKPIT ENCLOSURE DOORS), WHICH PRECIPITATED A LOSS OF DIRECTIONAL CONTROL.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- September 20, 1994 · about 3:00 pm local time
- Place
- Princeton, Illinois · map
- Type
- Accident
- Injuries
- No one was hurt; 2 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Amateur-built CHALLENGER II CHALLENGER
- Registration
- UNREG · no longer on the register
- Damage
- Substantial damage
- Flight
- Personal flight · ultralight rules (Part 103)
The NTSB's narrative final · quoted from the NTSB record
THE STUDENT PILOT REPORTED THAT AT ABOUT 1100 FEET ABOVE THE GROUND, THE AIRPLANE JOLTED, SHUDDERED, AND BEGAN TO TURN LEFT. THE BANK ANGLE BECAME PROGRESSIVELY STEEPER AND THE TURN PROGRESSIVELY TIGHTER. THE STUDENT PILOT SAID THAT IN AN ATTEMPT TO MAINTAIN CONTROL, HE APPLIED RIGHT RUDDER AND RIGHT AILERON, BUT THE AIRPLANE DID NOT RESPOND. THE AIRPLANE ENTERED INTO A DIVE TO THE LEFT AND IMPACTED A BEAN FIELD. THE STUDENT PILOT'S FIRST FLIGHT IN THE CHALLENGER, WITHOUT THE OPTIONAL KIT DOORS, WAS TAKEN THE DAY BEFORE THE ACCIDENT. HOWEVER, THE DOORS WERE INSTALLED AT THE TIME OF THE ACCIDENT.
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: student
- Medical certificate: Class 3 (valid medical--no waivers/lim.)
- Seat: frt
The aircraft
- Last inspection: inspection type not recorded
- Landing gear: fixed
- Engine: Rotax (piston); 0 hours total
The flight
- Departed from: C94 Erie IL
- Destination: NONE Argos IN
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 240° at 7 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 72°F (22°C), dew point 50°F (10°C)
- Altimeter: 30.00 inHg
- Observation at 2:45 pm from VYS
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 | |||
| Passengers | 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 UNREG 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.