Amateur-built TIERRA-2 accident near Prole, Iowa, August 26, 1994
On August 26, 1994, a amateur-built TIERRA-2, registered N6161Q, was destroyed in an accident near Prole, Iowa (Chandler Field). It was a personal flight under general aviation rules (Part 91). 2 people had minor injuries. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
the airplane's encounter with the outflow (gust front) from an approaching thunderstorm. Factors were the pilot's inaccurate evaluation of the gust front location, and the inability of the airplanes flight control system to compensate for the rolling moment.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- August 26, 1994
- Place
- Prole, Iowa · Chandler Field · map
- Type
- Accident
- Injuries
- 2 people had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft
- Amateur-built TIERRA-2
- Registration
- N6161Q · registry record · serial 1
- Damage
- Destroyed
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
DURING CRUISE FLIGHT, THE TWO-SEAT REGISTERED ULTRALIGHT AIRCRAFT ENCOUNTERED THE GUST FRONT FROM AN APPROACHING THUNDERSTORM WHICH WAS LOCATED 7 TO 15 MILES AWAY. THE ULTRALIGHT ENTERED AN UNCOMMANDED RIGHT DESCENDING BANK, WHICH THE PILOT COULD COULD NOT ARREST WITH FULL OPPOSITE AILERON INPUT. THE ULTRALIGHT IMPACTED TREES AND WAS DESTROYED.
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; rotorcraft: glider
- Flight time: 9,111 hours in all; 27 in this make and model; 97 in the last 90 days; 36 in the last 30 days; 8,904 as pilot in command; 657 on instruments
- Medical certificate: Class 2 (valid medical--no waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 97 hours
- Last inspection: annual inspection, January 4, 1995; 42 hours since
- Maximum gross weight: 800 lb
- Seats: 2
- Landing gear: fixed
- Engine: Rotax 532 (piston); 0 hours total
The flight
- Departed from: NONE Des Moines IA
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 88°F (31°C), dew point 0°F (-18°C)
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.
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.