Cessna 525 and Cessna 172N mid-air collision near Marietta, Georgia, April 4, 1998
On April 4, 1998 at about 3:32 pm local time, 2 aircraft, Cessna 525 (N111LR) and Cessna 172N (N737WD), were involved in a mid-air collision near Marietta, Georgia. 5 people were killed. The weather was visual conditions (good weather).
Preview. This page is not yet listed for search engines.
The NTSB's probable cause their words, unchanged
The failure of both pilots to see and avoid conflicting traffic, and the failure of the 172 pilot to operate the transponder as required by current regulations. Factors were the controller's failure to observe the traffic conflict, the lack of radar conflict alert capability, and the training emphasis on maximum autopilot usage with the autopilot controller placed at the rear of the cockpit center mounted pedestal.
The failure of both pilots to see and avoid conflicting traffic, and the failure of the 172 pilot to operate the transponder as required by current regulations. Factors were the controller's failure to observe the traffic conflict, the lack of radar conflict capability, and the training emphasis on maximum autopilot usage with the autopilot controller placed at the rear of the cockpit center mounted pedestal.
Source: NTSB aviation accident database, copy made October 4, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- April 4, 1998 · about 3:32 pm local time
- Place
- Marietta, Georgia · map
- Type
- Accident · mid-air collision
- Injuries
- 5 people were killed.
- Weather
- visual conditions (good weather)
- Aircraft 1
- Cessna 525 · all 525s on the register
- Registration
- N111LR · registry record · serial 525-0222
- Damage
- Destroyed
- Flight
- Business flight · general aviation rules (Part 91)
- Aircraft 2
- Cessna 172N · all 172Ns on the register
- Registration
- N737WD · no longer on the register · serial 17269724
- Damage
- Destroyed
- Flight
- Business flight · general aviation rules (Part 91)
The NTSB's narrative for the Cessna 525 final · quoted from the NTSB record
A Cessna 525 and a Cessna 172 collided in flight about 3,400 feet mean sea level on converging courses, with the 525 heading north and the 172 heading southwest. The converging speed was about 300 knots. The 525 departed under instrument flight rules, received vectors, and was initiating a climb on course. Training in the 525 emphasizes maximum use of the autopilot to afford greater outside scanning by the single pilot. The 525 was in radio contact with terminal approach control and the pilot's acknowledgement of the climb clearance was interrupted by the collision. The 172 had departed a local airfield, located just outside the 30 mile Mode C veil airspace of a terminal airport, and proceeded southwest. The collision occurred as the 172 was approaching Class D airspace of a military tower, and the pilot was initiating radio contact with the military tower. The terminal approach controller in contact with the 525 stated he did not observe the primary target of the 172, and conflict alert software was not installed. The 172 did not display a transponder signal and the transponder switch was subsequently found in the 'off' position. A cockpit visibility study indicated that from a fixed eye position the 172 was essentially hidden behind aircraft structure of the 525 for the 125 seconds before impact. The 172 could be seen by shifting the pilot's eye position. The 525 was viewable in the left lower section of the 172's windscreen. Both airplanes were operating in visual flight conditions.
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 172N final · quoted from the NTSB record
A Cessna 525 and a Cessna 172 collided in flight about 3,400 feet mean sea level on converging courses, with the 525 heading north and the 172 heading southwest. The converging speed was about 300 knots. The 525 departed under instrument flight rules, received vectors, and was initiating a climb on course. Training in the 525 emphasizes maximum use of the autopilot to afford greater outside scanning by the single pilot. The 525 was in radio contact with terminal approach control and the pilot's acknowledgement of the climb clearance was interrupted by the collision. The 172 had departed a local airfield, located just outside the 30 mile Mode C veil airspace of a terminal airport, and proceeded southwest. The collision occurred as the 172 was approaching Class D airspace of a military tower, and the pilot was initiating radio contact with the military tower. The terminal approach controller in contact with the 525 stated he did not observe the primary target of the 172, and conflict alert software was not installed. The 172 did not display a transponder signal and the transponder switch was subsequently found in the 'off' position. A cockpit visibility study indicated that from a fixed eye position the 172 was essentially hidden behind aircraft structure of the 525 for the 125 seconds before impact. The 172 could be seen by shifting the pilot's eye position. The 525 was viewable in the left lower section of the 172's windscreen. Both airplanes were operating in visual flight conditions.
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 525 from the NTSB's investigation tables, in plain English
Pilot
- Certificate: airline transport pilot, private
- Ratings: multi-engine land; single-engine land; instrument: airplane
- Flight time: 1,824 hours in all; 86 in this make and model; 81 in the last 90 days; 4 in the last 30 days; 1,772 as pilot in command
- Medical certificate: Class 1 (valid medical--w/ waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 181 hours
- Last inspection: approved inspection programme, March 29, 1998
- Maximum gross weight: 10,500 lb
- Seats: 8
- Landing gear: retractable
- Engine: Williams Intl FJ44-1A (turbojet); 0 hours total
The flight
- Departed from: PDK Chamblee GA at 3:30 pm
- Destination: MDT Harrisburg PA
- Flight plan: IFR
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 320° at 12 knots, gusting 20
- Visibility: 10 statute miles
- Sky: overcast at 3,300 ft
- Temperature: 54°F (12°C), dew point 46°F (8°C)
- Altimeter: 29.00 inHg
- Observation at 2:53 pm from PDK, 9 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 | |||
| Passengers | 3 |
The factual record for the Cessna 172N 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: 13,958 hours in all; 67 in the last 90 days; 13 in the last 30 days
- Medical certificate: Class 2 (valid medical--no waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 13,744 hours
- Last inspection: annual inspection, March 28, 1998
- Maximum gross weight: 2,150 lb
- Seats: 4
- Landing gear: fixed
- Engine: Lycoming O-320-H2AD (piston); 0 hours total
- Fire on the ground
The flight
- Departed from: 84A Cumming GA at 10:25 am
- Flight plan: none
- Runway 0
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 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.
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 ATL98FA060.