Witnessed an interesting and eye opening situation at MKE a few days ago.

I was flying MKE-PHL-BOS on 1/4, the MKE-PHL being operated by an Air Wisconsin CRJ200 (Never again ). Got to the airport at 1.5 hours before departure, got to gate about 45 mins prior to boarding. The inbound flight was just pulling into the gate ready for a quick turnaround back to Philly. Pulled in, crew came off and new crew came on; the leaving crew told the new crew that there was a small issue with the thrust reverser and that everything should be fine and a repair can be done in Philly. A few mins passed and we were about ready to board, and got a notification on my phone that my 11:30am on-time flight was now delayed until 1pm. Started getting concerned. I go up to the gate agent and show her the notification, she checks her computer, and is surprised to see that the flight now leaves at 1pm due to MX. She had absolutely no idea. I overheard some conversations between the flight crew and the agent, and even the flight crew was not aware that the flight would be delayed. So agent finally calls dispatch and asks what happened, dispatch tells her that they decided to do the repair in MKE since it is an Air Wisconsin MX base since the crew reported the issue on the flight in. Agents rebook connecting flights and since there are no AA flights after 11:30, the agents' shift ends and they leave. Meanwhile a bunch of pax are just sitting there doing nothing and I oversee MX fixing the engine, and they leave the plane at around 12:15.

Agent comes back at around 12:45, sees that no one is around the plane, and is now complaining that no one called her to say that the plane is fixed and she can board everyone. No one called the flight crew either, which was sitting in a nearby gate area the whole time wishing they could get out of there faster. Agent goes up to the crew, asks them whats up, no one told them anything, she then calls MX, they said they left the plane a while ago (and didn't tell anyone). So the agent simply says "Let's do this then" and tell crew to go on the plane and simply starts boarding. Plane boarded in only a few minutes and we were ready to go, departing 1.5 hours late. Also, agent was extremely friendly, helpful, and understanding to the Pax during the delay which is good.

To me this whole situation wasn't that big of a deal since I had a long layover anyway, but this certainly raises questions about the communication here. If everything was properly communicated, we could have gotten out maybe 45 minutes earlier and the aircraft's next flight wouldn't have been delayed either. Never seen this kind of lack of communication at an airline before, it should really be improved.