I was on a train that hit a bicycle that had been left on the track. One air hose got disconnected, so they had to stop the train and have the conductor get off and reattach the hose. The train was fine. The conductor's shirt might have been ruined (grease stains). The bicycle was probably ruined too. Once the hose was reconnected, the train was able to continue and seemed to be fine. I think we lost about 10 minutes, maybe 20.
I was also on a train that hit a person. I'm not sure if that damage the train at all, but the delay was much greater. First, they kept us on the train while the police investigated the death. The crew was driven away in a car for drug testing, even though it obviously wasn't their fault. The passengers had to get off the train and get on another one. We were about 3 hours late.