Tubeworker has already reported on London Underground's attempts to cut the frequency of essential fleet safety checks with its daft and reckless 'maintenance optimisation' policy. Now the company has come up with another daft scheme to save money with scant regard to safety - this time, on the Metropolitan line.
At present, if a train wheel develops a pit (ie. a dent) wider than 15mm, the wheel is unfit to continue in service. Then, suddenly, management decided that it was safe to continue with pits up to 30mm, and then got so carried away with themselves that they increased it again, to 45mm. That's the United Nations standard for the size of a satsuma! (Really, it is: check here.) You can imagine the risk to the wheel's stability, as well as the fact that wheels with pits and flats cause a lot of noise and vibration.
So, management reckon that it is safe to keep Met line train wheels in use when they have pits up to the size of a satsuma! Hands up who agrees with them. No, didn't think so.