Amateur-built TKD BATHTUB accident near Carlisle, Minnesota, August 21, 1989
On August 21, 1989 at about 1:00 am local time, a amateur-built TKD BATHTUB, registered N812SS, was substantially damaged in an accident near Carlisle, Minnesota. It was a personal flight under general aviation rules (Part 91). 1 person had minor injuries. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
FAILURE OF THE MIXTURE CONTROL CABLE AND INADEQUATE MAINTENANCE (REPAIR) BY THE PILOT. THE TERRAIN CONDITIONS WERE CONSIDERED TO BE CONTRIBUTING FACTORS.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- August 21, 1989 · about 1:00 am local time
- Place
- Carlisle, Minnesota · map
- Type
- Accident
- Injuries
- 1 person had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft
- Amateur-built TKD BATHTUB TKD BATHTU
- Registration
- N812SS · no longer on the register · serial 1
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
THE PLT SAID THAT DURING FLT, THE ENG OF THE HOME BUILT ACFT LOST POWER OVER ROUGH TERRAIN. DURING AN EMERGENCY LANDING, THE ACFT ENCOUNTERED TALL GRASS, ROCKS, GOPHER MOUNDS & DOWNWARD SLOPING TERRAIN, AND WAS DAMAGED. AN INVESTIGATION REVEALED THE MIXTURE CONTROL CABLE (PIANO WIRE) HAD FAILED AT A BOLT WHERE IT ATTACHED TO THE MIXTURE CONTROL LEVER. THIS WAS THE 2ND FAILURE DURING THE FLT FROM FARGO, ND TO FERGUS FALLS, MN. THE 1ST FAILURE OCCURRED ABOUT 15 TO 20 MIN INTO THE FLT. THE PLT MADE A SUCCESSFUL FORCED LANDING AFTER THE 1ST FAILURE, THEN BORROWED SOME TOOLS & REPAIRED THE CABLE. THE 2ND FAILURE OCCURRED ABOUT 10 TO 15 MIN AFTER HE TOOK OFF TO CONTINUE THE FLT.
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: commercial pilot
- Ratings: single-engine land; instrument: airplane; rotorcraft: balloon
- Flight time: 2,400 hours in all; 122 in this make and model
- Medical certificate: Class 2 (valid medical--no waivers/lim.)
- Seat: ctr
The aircraft
- Airframe total time: 122 hours
- Last inspection: annual inspection, June 23, 1989; 12 hours since
- Seats: 1
- Landing gear: fixed
- Engine: Franklin 2A-120-B (piston); 0 hours total
The flight
- Departed from: FAR Fargo ND
- Destination: FFM Fergus Falls MN
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 020° at 7 knots
- Visibility: 15 statute miles
- Sky: scat at 25,000 ft
- Temperature: 68°F (20°C), dew point 55°F (13°C)
- Altimeter: 29.00 inHg
- Observation at 10:51 pm from FFM, 10 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.
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.