Nicholas Lewis
Established Member
Back in 1952 the Harrow enquiry took place using information provided by British Railways staff thus there was no on site investigations by the railway inspectorate.Also possibly (and this is a guess) less information to collect by investigators?
It may be only at the instigation of RAIB that formal site investigations by staff independent of the railway industry personnel took place. Thus at Wickford or any other incident you have to wait until RAIB on call inspector attends attends site they will then have to call upon other specialists potentially. Thus depending on complexity of investigation requirements a period of time elapses before the site is handed over to NR.
By comparison, the Willesden breakdown crane was on site at Harrow 30 minutes after the accident took place, but it was a vastly different railway back then of course.