72 Stock to Serve Until 2030's

How about just use train dispatch staff?

there is no need to check trains at every platform, if they are reported by dispatch staff as heard then that would be adequate checking.

I'm sure Network Rail have remote wheelset monitoring equipment. In the recent 'Paddington Station 24/7' TV fly on the wall, an HST was taken out of service for wheelset examination with potential flats as it had tripped a detector on its inbound working and if I recall a maximum speed restriction of 50 mph was applied to the set with immediate effect to complete the journey with a prohibition on further use until after examination.

Hmm that video inspires a light bulb moment.

As stock on the Bakerloo gets older I guess the risk of wheel flats will rise for any rolling stock which lacks any form of wheel slip detection.

That video suggests that you could quickly and easily implement a very cheap wheel flat detection system - assuming there are still signalling staff employed somewhere.

Basically as trains shuttle back and forth along the same route it would only take providing the signallers cabin with a simple video camera feed with sound from a nearby platform which all trains are expected to transit.

I suspect it would not take very long for the signalling staff to notice any train producing such a loud thump thump sound, and likewise will pretty much ignore the sound of any which don't. Sort of like most car drivers quickly get tuned to what sounds are normal.

As and when a train sounds weird, presumably the signallers are ideally placed to identify the affected unit and get the maintenance staff to intervene to swap it out with another train whilst the problem is resolved. For very little investment the Bakerloo could potentially achieve very rapid pay-back through reduced track damage.