Beech C-99 and Rockwell 112TC mid-air collision near San Luis Obispo, California, August 24, 1984
On August 24, 1984 at about 6:18 pm local time, 2 aircraft, Beech C-99 (N6399U) and Rockwell 112TC (N112SM), were involved in a mid-air collision near San Luis Obispo, California (San Loui Obispo airport). 17 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 4, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- August 24, 1984 · about 6:18 pm local time
- Place
- San Luis Obispo, California · San Loui Obispo · map
- Type
- Accident · mid-air collision
- Injuries
- 17 people were killed.
- Weather
- visual conditions (good weather)
- Aircraft 1
- Beech C-99 · all C-99s on the register
- Registration
- N6399U · registry record · serial U-187
- Damage
- Destroyed
- Flight
- Flight of an unrecorded kind · charter and air-taxi rules (Part 135)
- Aircraft 2
- Rockwell 112TC
- Registration
- N112SM · registry record · serial 13020
- Damage
- Destroyed
- Flight
- Instructional flight · general aviation rules (Part 91)
The NTSB's narrative for the Beech C-99 final · quoted from the NTSB record
AT ABOUT 1118, A BEECH C-99 (WINGS WEST FLT 628), N6399U, & A ROCKWELL 112TC, N112SM, COLLIDED IN MIDAIR ABOUT 8 MI WEST-NORTHWEST OF THE SAN LOUI OBISPO COUNTY ARPT. THE ROCKWELL 112TC HAD DEPARTED PASO ROBLES, CA & WAS DESCENDING TOWARD THE SAN LOUI OBISPO COUNTY ARPT. THE BEECH C-99 HAD DEPARTED SAN LOUI OBISPO & WAS CLIMBING ON A FLT TO SAN FRANCISCO. THEY COLLIDED HEAD-ON AT ABOUT 3400 FT MSL IN CLEAR WX. THE C-99 CREW HAD JUST CONTACTED LOS ANGELES ARTCC. AT THAT TIME, THE AIRCREWS OF BOTH ACFT WERE GOVERNED BY THE 'SEE-AND-AVOID' CONCEPT WITH REGARD TO EACH OTHER. AN INVESTIGATION REVEALED THAT THE STANDARD DEPARTURE & INSTRUMENT APCH PROCEDURES SHARED A COMMON TRACK. THE C-99 WAS DEPARTING ALONG THE DEPARTURE TRACK. JUST PRIOR TO THE COLLISION, THE 112TC CREW HAD CONTACTED UNICOM & REPORTED AT THE DOBRA INTERSECTION WHICH WAS ON THE ILS APCH COURSE. AFTER COLLIDING, BOTH ACFT CRASHED ON OPEN TERRAIN & BURNED. THE CONTROLLER HAD ONLY SECONDS TO APPRAISE RADAR DATA & ISSUE A SAFETY ADVISORY. WINGS WEST REQD 1 RADIO ON COMPANY FREQ.
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 NTSB's narrative for the Rockwell 112TC final · quoted from the NTSB record
AT ABOUT 1118, A BEECH C-99 (WINGS WEST FLT 628), N6399U, & A ROCKWELL 112TC, N112SM, COLLIDED IN MIDAIR APRX 8 MI WEST-NORTHWEST OF THE SAN LOUI OBISPO COUNTY ARPT. THE ROCKWELL 112TC HAD DEPARTED PASO ROBLES, CA & WAS DESCENDING TOWARD THE SAN LOUI OBISPO COUNTY ARPT. THE BEECH C-99 HAD DEPARTED SAN LOUI OBISPO & WAS CLIMBING ON A FLT TO SAN FRANCISCO. THEY COLLIDED HEAD-ON AT ABOUT 3400 FT MSL IN CLEAR WX. THE C-99 CREW HAD JUST CONTACTED LOS ANGELES ARTCC. AT THAT TIME, THE AIRCREWS OF BOTH ACFT WERE GOVERNED BY THE 'SEE-AND-AVOID' CONCEPT WITH REGARD TO EACH OTHER. AN INVESTIGATIONREVEALED THAT THE STANDARD DEPARTURE & INSTRUMENT APCH PROCEDURES SHARED A COMMON TRACK. THE C-99 WAS DEPARTING ALONG THE DEPARTURE TRACK. JUST PRIOR TO THE COLLISION, THE 112TC CREW HAD CONTACTED UNICOM & REPORTED AT THE DOBRA INTER- SECTION WHICH WAS ON THE ILS APCH COURSE. AFTER COLLIDING, BOTH ACFT CRASHED ON OPEN TERRAIN & BURNED. THE CONTROLLER HAD ONLY SECONDS TO APPRAISE RADAR DATA & ISSUE A SAFETY ADVISORY. WINGS WEST REQD 1 RADIO TO BE TUNED TO COMPANY FREQ.
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 for the Beech C-99 from the NTSB's investigation tables, in plain English
Pilot
- Certificate: airline transport pilot, commercial pilot
- Ratings: multi-engine land; single-engine land; instrument: airplane
- Flight time: 4,110 hours in all; 873 in this make and model; 271 in the last 90 days; 91 in the last 30 days
- Medical certificate: Class 1 (valid medical--no waivers/lim.)
- Seat: unk
The aircraft
- Last inspection: inspection type not recorded; 0 hours since
- Maximum gross weight: 11,300 lb
- Seats: 17
- Landing gear: retractable
- Engine: P&W PT6A (turboprop); 0 hours total
- Fire on the ground
- Operator: Wings West Airlines, INC.
The flight
- Departed from: San Luis Obispo CA at 7:00 am
- Destination: San Francisco CA
- Flight plan: IFR
- Runway 0
- A second pilot was aboard
Weather at the time
- Light: daylight
- Wind: from 240° at 3 knots
- Visibility: 15 statute miles
- Sky: clear
- Temperature: 75°F (24°C), dew point 0°F (-18°C)
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 2 | |||
| Passengers | 13 |
The factual record for the Rockwell 112TC from the NTSB's investigation tables, in plain English
Pilot
- Certificate: commercial pilot
- Ratings: multi-engine land; single-engine land; instructor: airplane multi-engine; instructor: airplane single-engine; instrument: airplane
- Flight time: 4,858 hours in all; 73 in this make and model; 251 in the last 90 days; 93 in the last 30 days
- Medical certificate: Class 2 (valid medical--w/ waivers/lim.)
- Seat: unk
The aircraft
- Last inspection: inspection type not recorded; 0 hours since
- Maximum gross weight: 2,850 lb
- Seats: 4
- Landing gear: retractable
- Engine: Lycoming TO-360 (piston); 0 hours total
- Fire on the ground
The flight
- Departed from: Paso Robles CA at 7:00 am
- Flight plan: none
- Runway 0
- A second pilot was aboard
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.
About this page
Everything above comes from the NTSB's public accident database: the narrative, probable cause and findings are the NTSB's own words, and the coded tables behind its report (pilot, aircraft, flight, weather, injuries, sequence of events) are written out in plain English. Pilots' ages, home towns and medical details are left out on purpose. The documents and photographs are the NTSB's docket, the folder of records gathered during the investigation, shown as the NTSB released them (the NTSB redacts some personal details first) and listed under the NTSB's own titles. This site's own text never names pilots, passengers or anyone else involved. A preliminary report describes what is known soon after the event and can change; the final report, with the probable cause, usually follows one to two years later and this page is refreshed when it does. Case number DCA84AA034.