On August 7, 2017, PenAir filed for Chapter 11 bankruptcy. PenAir made the decision to end all flights out of its Denver and Portland hubs. Routes in California and Oregon that were not funded by Essential Air Service subsidies were terminated within days. The terms of the Essential Air Service contract required that PenAir continue to operate those routes until a new airline could be awarded the contract, a process expected to be completed within 90 days. On August 30, 2017, PenAir announced it would cease all Denver operations effective after September 10, 2017 due to a mass resignation involving 17 crew members.