Aero Commander 690A accident near Bishop, California, August 26, 1993
On August 26, 1993 at about 9:30 pm local time, a Aero Commander 690A, registered N706KC, was substantially damaged in an accident near Bishop, California. It was a flight of an unrecorded kind under general aviation rules (Part 91). 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
a loss of control and upset due to an inadequate adjustment of the ailerons and aileron trim tab by company maintenance personnel that resulted in a partial failure of the right horizontal stabilizer.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- August 26, 1993 · about 9:30 pm local time
- Place
- Bishop, California · map
- Type
- Accident
- Injuries
- No one was hurt; 2 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Aero Commander 690A · all 690As on the register
- Registration
- N706KC · no longer on the register · serial 11343
- Damage
- Substantial damage
- Flight
- Flight of an unrecorded kind · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
A TWIN ENGINE TURBOPROP AIRPLANE WAS DESCENDING THROUGH 16,500 FEET AT 205 KNOTS WHEN THE AIRPLANE BEGAN AN UNCOMMANDED 360- DEGREE RIGHT ROLL. THE PILOT REGAINED CONTROL OF THE AIRPLANE AND CONTINUED HIS DESCENT AND LANDED. AFTER LANDING, THE PILOT FOUND THAT THE OUTBOARD HALF OF THE RIGHT HORIZONTAL STABILIZER HAD BROKEN, FOLDING UP AND AFT 180 DEGREES OVER THE UPPER SURFACE OF THE STABILIZER. THE FAILURE OF THE STABILIZER WAS ATTRIBUTED TO OVERLOAD. METEOROLOGICAL CONDITIONS WERE DESCRIBED AS A LIGHT-TO-MODERATE CHOP. EXAMINATION OF THE AIRPLANE REVEALED OVERTRAVEL OF THE ELEVATORS AND AILERONS. NO OTHER STRUCTURAL DAMAGE WAS FOUND. THE AILERONS AND AILERON TRIM TAB WERE OUT OF ADJUSTMENT.
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, commercial pilot, flight engineer
- Ratings: multi-engine land; single-engine land; instructor: airplane single-engine; instructor: instrument airplane; instrument: airplane
- Flight time: 8,595 hours in all; 2,364 in this make and model; 150 in the last 90 days; 50 in the last 30 days; 7,860 as pilot in command; 28 on instruments
- Medical certificate: Class 1 (valid medical--no waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 4,037 hours
- Last inspection: approved inspection programme, August 25, 1993; 3 hours since
- Maximum gross weight: 10,325 lb
- Seats: 3
- Landing gear: retractable
- Engine: Garrett 331-5-251K (turboprop); 0 hours total
- Operator: Medic Air INC.
The flight
- Departed from: RNO Reno NV at 9:00 pm
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 180° at 10 knots
- Visibility: 50 statute miles
- Sky: clear
- Temperature: 90°F (32°C), dew point 39°F (4°C)
- Altimeter: 30.00 inHg
- Observation at 8:50 pm from BIH, 39 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 2 |
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.