Israel Aircraft Industries 1124A accident near Milwaukee, Wisconsin, December 26, 1999
On December 26, 1999 at about 1:15 pm local time, a Israel Aircraft Industries 1124A, registered N422BC, was substantially damaged in an accident near Milwaukee, Wisconsin (General Mitchell Intl airport). It was a business flight under general aviation rules (Part 91). 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 failure of the first stage pressure reducer in the oxygen regulator assembly.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- December 26, 1999 · about 1:15 pm local time
- Place
- Milwaukee, Wisconsin · General Mitchell Intl · map
- Type
- Accident
- Injuries
- No one was hurt; 6 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Israel Aircraft Industries 1124A · all 1124As on the register
- Registration
- N422BC · registry record · serial 302
- Damage
- Substantial damage
- Flight
- Business flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
During the activation of the crew oxygen system a fire erupted which consumed the entire pressure vessel. Representatives from the National Aeronautics and Space Administration's (NASA) Johnson Space Center (JSC), White Sands Testing Facility (WSTF), Las Cruces, New Mexico, examined the retained oxygen system components. Examination of these components revealed that the fire's initiation location was the first stage pressure reducer located in the oxygen regulator assembly.
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, commercial pilot
- Ratings: multi-engine land; single-engine land; instructor: airplane single-engine; instrument: airplane
- Flight time: 14,363 hours in all; 2,024 in this make and model; 125 in the last 90 days; 30 in the last 30 days; 10,408 as pilot in command
- Medical certificate: Class 1 (valid medical--no waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 7,975 hours
- Last inspection: continuous airworthiness programme, August 20, 1999; 116 hours since
- Maximum gross weight: 23,500 lb
- Seats: 0
- Landing gear: retractable
- Engine: Garrett TFE731-3-1G (turbofan); 0 hours total
- Fire on the ground
The flight
- Departed from: MKE at 1:15 pm
- Destination: UES Waukesha WI
- Flight plan: none
- Runway 0
- A second pilot was aboard
Weather at the time
- Light: dawn
- Wind: from 320° at 15 knots, gusting 31
- Visibility: 10 statute miles
- Sky: scat at 6,000 ft
- Temperature: 82°F (28°C), dew point 52°F (11°C)
- Altimeter: 29.00 inHg
- Observation at 1:27 pm from MKE
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 2 | |||
| Passengers | 4 |
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.