Guam - United Airlines vice president of safety who reports directly to the chief operating officer is flying in to participate in a roundtable discussion at the Guam Legislature on the topic of safety.  The roundtable meeting follows incidents over the past two weeks involving United Airlines. This past week another flight was delayed due to mechanical issues. The incident followed another one the week before week when hundreds of passengers who were heading to Hawaii on a United Airlines flight were delayed several times due to a seal issue in the cockpit window.   Senator Michael San Nicolas who chairs the Legislature's Committee on Aviation has scheduled a roundtable discussion for Wednesday at 6pm in the Legislature's Public Hearing Room.