Boeing 747-123 incident near Minneapolis, Minnesota, May 18, 1998
On May 18, 1998 at about 7:15 am local time, a Boeing 747-123, registered N675UP, was involved in an incident near Minneapolis, Minnesota. It was a flight of an unrecorded kind under scheduled airline rules (Part 121). No one was hurt; 3 people were on board or involved. The weather was conditions the NTSB did not record.
The NTSB's probable cause their words, unchanged
the open shielding on the #2 VHF transceiver coax connector which resulted in electromagnetic interference with the yaw damper system.
Source: NTSB aviation accident database, copy made November 2, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- May 18, 1998 · about 7:15 am local time · cases in 1998
- Place
- Minneapolis, Minnesota · map
- Type
- Incident
- Injuries
- No one was hurt; 3 people were on board or involved.
- Weather
- conditions the NTSB did not record
- Aircraft
- Boeing 747-123 · all 747-123s on the register
- Registration
- N675UP · registry record · serial 20390
- Damage
- Not recorded
- Flight
- Flight of an unrecorded kind · scheduled airline rules (Part 121)
The NTSB's narrative final · quoted from the NTSB record
While troubleshooting a fire warning indication with company maintenance control using the #2 VHF transceiver, the crew experienced several uncommanded 'kicks' of the yaw damper. The crew turned off the upper yaw damper, but not the lower. They continued to experience 'kicks' although not as severe. The flight departed to Minneapolis where it landed uneventfully. Inspection of the airplane after the incident revealed an open shield at the #2 VHF coax connector which is located near the yaw damper control box. The connector was replaced and the airplane was returned to service.
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 engineer
- Ratings: multi-engine land; single-engine land; instrument: airplane
- Flight time: 14,500 hours in all; 595 in this make and model
- Medical certificate: Class 1 (valid medical--no waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 58,165 hours
- Last inspection: continuous airworthiness programme, May 11, 1998
- Maximum gross weight: 734,000 lb
- Seats: 9
- Landing gear: fixed
- Engine: P&W JT9D-7AH (turbofan); 0 hours total
The flight
- Departed from: LOU Louisville KY
- Destination: ANC Anchorage AK
- Flight plan: IFR
- Runway 0
- A second pilot was aboard
Weather at the time
- Light: night, dark
- Sky: not recorded; not recorded
- Temperature: 0°F (-18°C), dew point 0°F (-18°C)
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 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.
Connections how this case links to the rest of the register
- N675UP on the register today · the tail number may have moved to another aircraft since
- Boeing 747 192 registered today · the model family and its accident history
- Boeing 6,677 aircraft on the register
- Engine: P&W JT9D-7AH 13 aircraft carry this series today · as the NTSB recorded it
- Bowman Field · departed from
- Ted Stevens Anchorage International · bound for
- Accidents and incidents in Minnesota 1,544 since 1982 · 209 in the last ten years
- Minnesota 6,953 aircraft registered
The whole map of how records connect · these connections as data: /graph/accident/CHI98IA164.json.
The bigger picture in Aviation Analytics: accidents over time since 1982, by model, by phase of flight and conditions, by place and on the map.
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 does not name anyone involved, its policy at this time. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.