Beech B36TC accident near Billings, Montana, January 5, 1985
On January 5, 1985 at about 1:25 am local time, a Beech B36TC, registered N6750C, was substantially damaged in an accident near Billings, Montana (Logan airport). It was a business flight under general aviation rules (Part 91). 1 person had minor injuries; 1 other was unhurt. 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
- January 5, 1985 · about 1:25 am local time
- Place
- Billings, Montana · Logan
- Type
- Accident
- Injuries
- 1 person had minor injuries; 1 other was unhurt.
- Weather
- visual conditions (good weather)
- Aircraft
- Beech B36TC · all B36TCs on the register
- Registration
- N6750C · registry record · serial 393
- Damage
- Substantial damage
- Flight
- Business flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
PLT USED CANNULA CONNECTED TO PORTABLE OXYGEN SYSTEM DURING CLIMB STARTING AT 11,000 FT MSL. AT FL 170 PLT SWITCHED TO A MASK CONNECTED TO ACFT OXYGEN STSTEM. AT FL 250, PLT COMPLAINED OF STOMACH PAINS FOR APRX 1/2 HR. PLT THEN STATED TO HIS SON THAT HIS OXYGEN SMELT BAD, THE MASK WAS AWKWARD TO USE AND IT FIT POORLY. AT THIS TIME THE PLT USED THE MASK AND CANNULA TOGETHER. THE ACFT OXYGEN SYSTEM WAS CHECKED AND INDICATED A POSITIVE FLOW WITH A BOTTLE PRESSURE OF 1500 PSI. PLT THEN BEGAN SHOWING SIGNS OF HYPOXIA AND SUBSEQUENTLY DRIFTED IN AND OUT OF CONSIOUSNESS. PLTS SON TOOK OVER CONTROLS, DECLARED AN EMERGENCY AND FLEW THE ACFT UNTIL FINAL APCH WHEN THE PLT TOOK CONTROL OF ACFT. PLT DIVED ACFT ON SHORT FINAL AND SON PULLED BACK ON YOKE. ACFT CONTACTED GROUND SHORT OF THE RWY. INSPECTION OF THE ACFT OXYGEN SYSTEM REVEALED NO MECHANICAL MALFUNCTION, HOWEVER, THE OXYGEN BOTTLE REPORTEDLY HAD AN APRX DEW POINT OF -35 DEG F. OXYGEN USED FOR AVIATION IS REQUIRED TO HAVE A DEW POINT OF -83 DEG F OR LESS.
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: multi-engine land; single-engine land; instrument: airplane
- Medical certificate: Class 2 (valid medical--no waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 218 hours
- Last inspection: 100-hour inspection, September 20, 1984; 20 hours since
- Maximum gross weight: 2,338 lb
- Seats: 6
- Landing gear: retractable
- Engine: Continental TSIO-520-UB (piston); 0 hours total
The flight
- Departed from: Seattle WA at 10:20 pm
- Destination: BIL Billings MT
- Flight plan: IFR
- Runway 22, 5,704 ft by 150 ft
Weather at the time
- Light: night, bright
- Wind: from 220° at 17 knots
- Visibility: 20 statute miles
- Sky: clear
- Temperature: 50°F (10°C), dew point 0°F (-18°C)
- Altimeter: 30.00 inHg
- Observation at 1:30 am from BIL
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 N6750C 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.