Boeing 737-200 incident near Chicago, Illinois, October 4, 1997
On October 4, 1997 at about 1:10 pm local time, a Boeing 737-200, registered N129SW, suffered minor damage in an incident near Chicago, Illinois (Midway airport). It was a flight of an unrecorded kind under scheduled airline rules (Part 121). No one was hurt; 50 people were on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
an improper repair to a crack in a brake flange hole on the left main landing gear outboard axle, and subsequent fatigue failure of the axle.
Source: NTSB aviation accident database, copy made October 4, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- October 4, 1997 · about 1:10 pm local time
- Place
- Chicago, Illinois · Midway · map
- Type
- Incident
- Injuries
- No one was hurt; 50 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Boeing 737-200 · all 737-200s on the register
- Registration
- N129SW · registry record · serial 22340
- Damage
- Minor damage
- Flight
- Flight of an unrecorded kind · scheduled airline rules (Part 121)
The NTSB's narrative final · quoted from the NTSB record
The left main landing gear outboard wheel/brake assembly separated from the airplane during a landing roll. The Captain did not report any difficulties in controlling the airplane. Inspection of the failed axle revealed a crack which originated at the surface of one of the brake flange holes. This crack had previously been repaired. Detailed metallurgical examination of the crack revealed properties consistent with the surface having been heated to an excessive temperature during the repair process.
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: airline transport pilot, flight instructor
- Ratings: multi-engine land; single-engine land; instrument: airplane
- Flight time: 16,100 hours in all; 5,600 in this make and model; 226 in the last 90 days; 85 in the last 30 days; 7,250 as pilot in command
- Medical certificate: Class 1 (valid medical--w/ waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 49,400 hours
- Last inspection: continuous airworthiness programme, August 20, 1997; 386 hours since
- Maximum gross weight: 115,500 lb
- Seats: 130
- Landing gear: retractable
- Engine: P&W JT8D-9 (turbofan); 0 hours total
- Operator: Southwest Airlines
The flight
- Departed from: MCI Kansas City MO at 12:10 pm
- Destination: MDW
- Flight plan: IFR
- Runway 31C, 6,522 ft by 150 ft
- A second pilot was aboard
Weather at the time
- Light: daylight
- Wind: from 240° at 10 knots
- Visibility: 6 statute miles
- Sky: overcast at 8,500 ft; scat at 6,000 ft
- Temperature: 70°F (21°C), dew point 64°F (18°C)
- Altimeter: 29.00 inHg
- Observation at 12:53 pm from MDW
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 5 | |||
| Passengers | 45 |
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 CHI98IA007.