Casualties unknown

Passenger Dies After Rapid Decompression, Coroner Rules Natural Causes (N217US)

Dayton, OH, US

On March 9, 1989, a Boeing 737-201 (registration N217US) was involved in an aviation accident near Dayton, OH. Investigators recorded the probable cause as: Uncontrollable outflow valve resulting in rapid decompression. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive; 2 related events involving the same aircraft type or operator are linked below.

Sourcesthe U.S. National Transportation Safety Board (NTSB) historical archivePrimary reportUpdated 2026-06-10Data APIEditorial standards
Aircraft registered N217US
Aircraft registered N217US. Photo: Aero Icarus from Zürich, Switzerland / CC BY-SA 2.0, via Wikimedia Commons

A passenger died after an uncontrollable outflow valve caused rapid decompression at FL310. No other occupants were injured, and the aircraft was undamaged. The coroner ruled the death due to natural causes.

Incident

A rapid decompression occurred at flight level 310 when an uncontrollable outflow valve malfunctioned. The oxygen masks deployed automatically, and the captain initiated an emergency descent to 10,000 feet. The flight continued to Dayton, landing at 1740 local time.

Investigation

Investigation revealed that the uncontrollable outflow valve was the direct cause of the rapid decompression. There was no damage to the airplane, and no injuries were reported among the remaining occupants.

Aftermath

The affected passenger was transported to a Dayton hospital, where they died approximately 6 hours and 50 minutes later. The Montgomery County Coroner determined that death was due to natural causes, not directly from the decompression incident.

Probable cause

Uncontrollable outflow valve resulting in rapid decompression

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001213X27829. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.