Cessna 172M and amateur-built DHC-1B-2-S5 accident near Bethany, Oklahoma, August 30, 1984
On August 30, 1984 at about 7:25 pm local time, 2 aircraft, Cessna 172M (N9646H) and amateur-built DHC-1B-2-S5 (N1PN), were involved in the same accident near Bethany, Oklahoma (Wiley Post Airport). No one was hurt; 4 people were on board or involved. 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
- August 30, 1984 · about 7:25 pm local time
- Place
- Bethany, Oklahoma · Wiley Post Airport · map
- Type
- Accident · collision on the ground
- Injuries
- No one was hurt; 4 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft 1
- Cessna 172M · all 172Ms on the register
- Registration
- N9646H · no longer on the register · serial 17266293
- Damage
- Substantial damage
- Flight
- Instructional flight · general aviation rules (Part 91)
- Aircraft 2
- Amateur-built DHC-1B-2-S5 DHC-1B-2-S
- Registration
- N1PN · registry record · serial 231
- Damage
- Minor damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative for the Cessna 172M final · quoted from the NTSB record
ACCORDING TO THE PLT OF N9646H, WHILE HE WAS TAXIING UNDER THE DIRECTION OF GROUND CONTROL THE ACFT WAS STRUCK FROM BEHIND BY N1PN. THE PLT OF N1PN STATED THAT HE WAS CLEARED TO TAXI AND DID NOT SEE ANY OTHER ACFT AS HE ENTERED THE TAXIWAY. SEATED IN THE REAR SEAT OF THE TANDEM SEAT ACFT THE PLT OF N1PN WAS PERFORMING 'S' TURNS IN AN EFFORT TO MAINTAIN VISUAL CLEARANCE WHEN THE WING OF N9646H WAS SEEN ALMOST SIMULTANEOUS WITH THE COLLISION. INITIAL CONTACT OCCURRED BETWEEN THE PROP OF THE OVERTAKING ACFT AND THE EMPENNAGE OF THE LEADING ACFT.
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 amateur-built DHC-1B-2-S5 final · quoted from the NTSB record
ACCORDING TO THE PLT OF N9646H, WHILE HE WAS TAXIING UNDER THE DIRECTION OF GROUND CONTROL THE ACFT WAS STRUCK FROM BEHIND BY N1PN. THE PLT OF N1PN STATED THAT HE WAS CLEARED TO TAXI AND DID NOT SEE ANY OTHER ACFT AS HE ENTERED THE TAXIWAY. SEATED IN THE REAR SEAT OF THE TANDEM SEAT ACFT THE PLT OF N1PN WAS PERFORMING 'S' TURNS IN AN EFFORT TO MAINTAIN VISUAL CLEARANCE WHEN THE WING OF N9646H WAS SEEN ALMOST SIMULTANEOUS WITH THE COLLISION. INITIAL CONTACT OCCURRED BETWEEN THE PROP OF THE OVERTAKING ACFT AND THE EMPENNAGE OF THE LEADING ACFT.
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 Cessna 172M 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: 4,034 hours in all; 482 in this make and model; 56 in the last 90 days; 3,793 as pilot in command
- Medical certificate: Class 2 (valid medical--no waivers/lim.)
- Seat: rgt
The aircraft
- Airframe total time: 3,121 hours
- Last inspection: 100-hour inspection, August 23, 1984
- Maximum gross weight: 2,300 lb
- Seats: 4
- Landing gear: fixed
- Engine: Lycoming O-320-E2D (piston); 0 hours total
The flight
- Flight plan: none
- Runway 0
- A second pilot was aboard
Weather at the time
- Light: daylight
- Wind: from 230° at 5 knots
- Visibility: 25 statute miles
- Sky: clear
- Temperature: 0°F (-18°C), dew point 0°F (-18°C)
- Altimeter: 30.00 inHg
- Observation at 6:50 pm from PWA
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 2 |
The factual record for the amateur-built DHC-1B-2-S5 from the NTSB's investigation tables, in plain English
Pilot
- Certificate: private
- Ratings: single-engine land; instrument: airplane
- Flight time: 1,031 hours in all; 5 in this make and model; 25 in the last 90 days; 810 as pilot in command
- Medical certificate: Class 3 (valid medical--w/ waivers/lim.)
- Seat: rear
The aircraft
- Airframe total time: 3,290 hours
- Last inspection: annual inspection, June 8, 1984; 0 hours since
- Maximum gross weight: 1,930 lb
- Seats: 2
- Landing gear: fixed
- Engine: Lycoming O-540 (piston); 0 hours total
- Operator: Thunderbird Park INC
The flight
- Flight plan: none
- Runway 0
- A second pilot was aboard
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 N9646H 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.