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Accidents · NTSB CHI98IA164 · Final report

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 October 5, 2026. Docket and reports at the NTSB.

What the record shows

Date
May 18, 1998 · about 7:15 am local time
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

FatalSeriousMinorNone
Crew3

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.