Cessna 172K and Cessna 172D mid-air collision near Greeneville, Tennessee, September 15, 1991
On September 15, 1991, 2 aircraft, Cessna 172K (N78239) and Cessna 172D (N73L), were involved in a mid-air collision near Greeneville, Tennessee. No one was hurt; 6 people were on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
THE INADEQUATE VISUAL LOOKOUT BY THE PILOT OF N78239, AND HIS FAILURE TO ACCURATELY JUDGE THE DISTANCE BETWEEN THE TWO AIRCRAFT. FACTORS IN THE ACCIDENT WERE THE DARK NIGHT CONDITIONS AND THE RESULTING VISUAL PERCEPTION OF AIRCRAFT LIGHTING IN DARK CONDITIONS.
THE INADEQUATE VISUAL LOOKOUT BY THE PILOT OF N78239, AND HIS FAILURE TO ACCURATELY JUDGE THE DISTANCE BETWEEN THE TWO AIRCRAFT. FACTORS IN THE ACCIDENT WERE THE DARK NIGHT CONDITIONS AND THE RESULTING VISUAL PERCEPTION OF AIRCRAFT LIGHTING IN DARK CONDITIONS.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- September 15, 1991
- Place
- Greeneville, Tennessee · map
- Type
- Accident · mid-air collision
- Injuries
- No one was hurt; 6 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft 1
- Cessna 172K · all 172Ks on the register
- Registration
- N78239 · registry record · serial 17257540
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
- Aircraft 2
- Cessna 172D · all 172Ds on the register
- Registration
- N73L · registry record · serial 17250283
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative for the Cessna 172K final · quoted from the NTSB record
BOTH PILOTS HAD PLANNED LOCAL SIGHTSEEING NIGHT FLIGHTS. BOTH AIRCRAFT WERE ON AN EASTERLY HEADING, WITH N78239 (A C172K) IN FRONT OF N73L (A C172D). THE AIRCRAFT WERE IN RADIO CONTACT WITH EACH OTHER AND ATC WAS NOT INVOLVED. N78239 INITIATED A 360-DEGREE TURN, AND VISUALLY ACQUIRED THE LIGHTS OF N73L AFTER RESUMING AN EASTERLY HEADING. THE PILOT OF N78239 STATED THAT 'SUDDENLY WE HIT'! ALTHOUGH AT THE TIME HE THOUGHT THE SPACING BETWEEN AIRCRAFT WAS ABOUT 2 MILES. N78239 LANDED WITHOUT FURTHER INCIDENT DESPITE FLIGHT CONTROL PROBLEMS. N73L LOST DIRECTIONAL CONTROL UPON LANDING AND COLLIDED WITH A PARKED AIRPLANE. INSPECTION OF BOTH AIRCRAFT REVEALED THAT N78239 STRUCK N73L FROM THE REAR, THE RIGHT WING LEADING EDGE OF N78239 CONTACTING THE LEFT MAIN LANDING GEAR OF N73L. THE IMPACT BROKE THE WING SPAR OF N78239 AND SEPARATED THE LEFT MAIN GEAR FROM N73L.
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 Cessna 172D final · quoted from the NTSB record
BOTH PILOTS HAD PLANNED LOCAL SIGHTSEEING NIGHT FLIGHTS. BOTH AIRCRAFT WERE ON AN EASTERLY HEADING, WITH N78239 (A C172K) IN FRONT OF N73L (A C172D). THE AIRCRAFT WERE IN RADIO CONTACT WITH EACH OTHER AND ATC WAS NOT INVOLVED. N78239 INITIATED A 360-DEGREE TURN, AND VISUALLY ACQUIRED THE LIGHTS OF N73L AFTER RESUMING AN EASTERLY HEADING. THE PILOT OF N78239 STATED THAT 'SUDDENLY WE HIT!' ALTHOUGH AT THE TIME HE THOUGHT THE SPACING BETWEEN AIRCRAFT WAS ABOUT 2 MILES. N78239 LANDED WITHOUT FURTHER INCIDENT DESPITE FLIGHT CONTROL PROBLEMS. N73L LOST DIRECTIONAL CONTROL UPON LANDING AND COLLIDED WITH A PARKED AIRPLANE. INSPECTION OF BOTH AIRCRAFT REVEALED THAT N78239 STRUCK N73L FROM THE REAR, THE RIGHT WING LEADING EDGE OF N78239 CONTACTING THE LEFT MAIN LANDING GEAR OF N73L. THE IMPACT BROKE THE WING SPAR OF N78239 AND SEPARATED THE LEFT MAIN GEAR FROM N73L.
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 172K from the NTSB's investigation tables, in plain English
Pilot
- Certificate: private
- Ratings: single-engine land
- Flight time: 2,200 hours in all; 125 in this make and model; 38 in the last 90 days; 18 in the last 30 days; 2,200 as pilot in command
- Medical certificate: Class 3 (valid medical--w/ waivers/lim.)
- Seat: unk
The aircraft
- Last inspection: inspection type not recorded; 0 hours since
- 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
Weather at the time
- Light: night, dark
- Wind: from 060° at 3 knots
- Visibility: 5 statute miles
- Sky: clear
- Temperature: 81°F (27°C), dew point 73°F (23°C)
- Altimeter: 30.00 inHg
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 | |||
| Passengers | 1 |
The factual record for the Cessna 172D from the NTSB's investigation tables, in plain English
Pilot
- Certificate: private
- Ratings: single-engine land
- Flight time: 220 hours in all; 92 in this make and model; 35 in the last 90 days; 5 in the last 30 days; 192 as pilot in command
- Medical certificate: Class 3 (valid medical--w/ waivers/lim.)
- Seat: unk
The aircraft
- Last inspection: inspection type not recorded; 0 hours since
- Maximum gross weight: 2,300 lb
- Seats: 4
- Landing gear: fixed
- Engine: Continental O-300-D (piston); 0 hours total
The flight
- Flight plan: none
- Runway 0
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 | |||
| Passengers | 3 |
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 N78239 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.