Boeing 737-3B7 incident near Indianapolis, Indiana, September 21, 1993
On September 21, 1993 at about 3:17 pm local time, a Boeing 737-3B7, registered N527AU, was involved in an incident near Indianapolis, Indiana. It was a flight of an unrecorded kind under scheduled airline rules (Part 121). No one was hurt; 88 people were on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
an undetermined problem which resulted in the physical impairment of flight attendants, passengers and the first officer.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- September 21, 1993 · about 3:17 pm local time
- Place
- Indianapolis, Indiana · map
- Type
- Incident
- Injuries
- No one was hurt; 88 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Boeing 737-3B7 · all 737-3B7s on the register
- Registration
- N527AU · no longer on the register · serial 23842
- Damage
- Not recorded
- Flight
- Flight of an unrecorded kind · scheduled airline rules (Part 121)
The NTSB's narrative final · quoted from the NTSB record
DURING FLIGHT THE FLIGHT ATTENDANTS COMPLAINED OF HYPOXIA SYMPTOMS. THE FIRST OFFICER INVESTIGATED THE AIRPLANE'S CABIN WITH NEGATIVE RESULTS. THE FLIGHT ATTENDANTS REPORTED THEY HAD HYPOXIA SYMPTOMS TO THE FLIGHT CREW A SECOND TIME AND THIS TIME THEIR FINGERNAILS HAD TURNED BLUE. THE CAPTAIN REQUESTED, AND RECEIVED, AN ATC CLEARANCE TO DIVERT TO AND LAND AT INDIANAPOLIS. HOSPITAL EXAMINATION OF THE FLIGHT ATTENDANTS AND FOUR PASSENGERS REVEALED NO CARBON MONOXIDE POISONING. THE HOSPITAL REPORTS STATED THERE WAS 'POSSIBLE TOXIC INHALATIONAL EXPOSURE.' THE AIRPLANE WAS CHECKED FOR CARBON MONOXIDE AND ORGANIC VAPORS DURING GROUND RUNUP AND FERRY FLIGHT TO THE COMPANY'S MAINTENANCE CENTER WITH NEGATIVE RESULTS.
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
- Ratings: multi-engine land; instrument: airplane
- Flight time: 20,029 hours in all; 2,983 in this make and model; 131 in the last 90 days
- Medical certificate: Unknown
- Seat: left
The aircraft
- Airframe total time: 18,151 hours
- Last inspection: annual inspection, September 17, 1993
- Maximum gross weight: 220,000 lb
- Seats: 2
- Landing gear: retractable
- Engine: Ge CF-56-3B2 (turbofan); 0 hours total
The flight
- Departed from: PHI Philadelphia PA
- Destination: MCI Kansas City MO
- Flight plan: IFR
- Runway 0
- A second pilot was aboard
Weather at the time
- Light: daylight
- Visibility: 7 statute miles
- Sky: overcast at 1,600 ft; not recorded at 1,600 ft
- Temperature: 0°F (-18°C), dew point 0°F (-18°C)
- Altimeter: 30.00 inHg
- Observation at 1:52 pm from IND
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 6 | |||
| Passengers | 82 |
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.
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.