Question: United Express Flight 3411 incident occurred on April 9, 2017, O'Hare International Airport police violently and forcibly ejected passenger David Dao from United Express Flight 3411 after he refused to depart the airplane upon the demand of management, which airline subsidiary operated the scheduled passenger flight, on behalf of United Express?
Sentence (from "United Express Flight 6291"): It was a service operated by Atlantic Coast Airlines on behalf of United Express.
Relevant evidence: No