i guess in retroexpect, was there some way -- retrospect, was there some way we could know these trains -- how old are these? >> 20 years old. >> supervisor mandelman: so 20 years ago, did someone screw up, and when we spent hundreds of millions of dollars acquiring a fleet, that we're acquiring a fleet that's going to last us not 20 years, but 30 years. >> yeah. i think there were a number of contributing factors. the first is that the bredas were designed in what i would call an overly prescriptive way. when we acquired the l.r.v. 4's, we did a request for information from the industry, and we said these are the -- our challenges, this is what we're struggling with. what's the state of the industry, and then, we developed a performance-based spec. so for example, in the bredas, we said exactly how we wanted the doors and steps are designed, which ended up with a model that have about 100 mechanical levers, all of which have to be perfectly aligned to work. second, we said the doors and steps aren't going to breakdown except maybe once a year. how do you want to design them to meet tha