My Terminal Tower Story:
About 1994, before the Terminal Tower interlocking was rebuilt by Metrolink, the switches were air-operated. One of the MOW guys working for me drove his truck over an above-ground air pipe and broke it which caused a tremendous hissing sound. The Terminal Tower operator called out the air pressure drop on the radio like he was counting down for a rocket launch. When he got to to some low number like zero, he said '..and we're out of service!' I was having a good morning until then, but fortunately it was after the morning rush and the maintainers were able to patch up the pipe in a short time and I don't think any trains were delayed.
The track and signals in that area was overdue for replacement and Metrolink was gearing up for a total rebuilding of the area. In the meantime, we put a welder there full-time to 'repair' (i.e. 'patch') the frogs and switch points. Was always fun when the FRA inspector walked the terminal area with us although the only violation I recall was a BS compromise joint bar issue for rails that had the same cross section!