Amateur-built TIERRA II accident near Post Falls, Idaho, September 29, 1985
On September 29, 1985 at about 6:19 pm local time, a amateur-built TIERRA II, registered UNREG, was destroyed in an accident near Post Falls, Idaho. It was a flight of an unrecorded kind under general aviation rules (Part 91). 2 people were killed. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The NTSB has not yet published a probable cause for this accident. Investigations usually take one to two years; this page updates when the final report is released.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- September 29, 1985 · about 6:19 pm local time
- Place
- Post Falls, Idaho · map
- Type
- Accident
- Injuries
- 2 people were killed.
- Weather
- visual conditions (good weather)
- Aircraft
- Amateur-built TIERRA II
- Registration
- UNREG · no longer on the register
- Damage
- Destroyed
- Flight
- Flight of an unrecorded kind · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
THE ACFT CONTACTED THE TERRAIN IN AN UNCONTROLLED DESCENT FOLLOWING AN INFLT SEPARATION OF THE LEFT WING. A WITNESS STATED THE LEFT WING SEPARATED AS THE ACFT WAS BEING MANEUVERED IN A RACE TRACK PATTERN USING BANK ANGLES OF 45 DEGS. THE WIFE OF THE ACFT OWNER REPORTED THE ACFT WAS DAMAGED DURING AN INSTRUCTIONAL FLT ON THE PREVIOUS DAY. THE LEFT WING AND LANDING GEAR WERE REPORTEDLY DAMAGED IN THE ACCIDENT. THE ACFT WAS SAID TO HAVE BEEN REPAIRED THAT AFTERNOON. HOWEVER, NO EVIDENCE WAS FOUND TO SUGGEST THE FABRIC ON THE WING WAS REMOVED FOR INSPECTION OF STRUCTURAL DAMAGE. IT WAS NOT DETERMINED IF THE FLIGHT WAS FOR PERSONAL OR INSTRUCTIONAL PURPOSES.
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: private
- Ratings: single-engine land
- Flight time: 700 hours in all
- Medical certificate: Class 3 (valid medical--w/ waivers/lim.)
- Seat: rgt
The aircraft
- Last inspection: inspection type not recorded
- Seats: 2
- Landing gear: fixed
- Engine: Rotax 532 (piston); 0 hours total
The flight
- Departed from: Liberty Lake WA at 5:30 pm
- Flight plan: none
- Runway 0
- A second pilot was aboard
Weather at the time
- Light: daylight
- Visibility: 20 statute miles
- Sky: clear
- Temperature: 46°F (8°C), dew point 25°F (-4°C)
- Altimeter: 30.00 inHg
- Observation at 5:43 pm from COE, 10 miles away
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.