Present Talgo Train trails are indeed of great importance to Indian Railways, but real trial will be the one when the following lacunae are taken care of :
(1) the original Talgo Electric Locos at ends of train sets are to be used to haul the train rather then our WDP4 loco. Then only we can ensure that our overhead Electrification catenary wires could sustain such high speeds and are compatible with Talgo pantograph.
(2) the speed is 170+kmph i.e. above Gatiman Express Operational Speed. Below that it does not make much...
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sense. We have extrapolated the lower limit of Semi High Speed of a train to 160kmph in Indian context, but globally SHS range is around 200-250kmph.
(3) Also theTalgo train length is only 210m where as Rajdhani Express with 21 LHB coaches and a loco is about 525M. Successful Talgo trial of 210M rake does not guarantee success run for 525M long full length Talgo rake.
Mumbai Rajdhani could achieve 85kmph average speed with booked speed of 130kmph thru most of its run due to fact that it has been accorded extremely high priority over other trains. For Talgo train to achieve 125kmph avg speed in Delhi- Mumbai run, the operational speed has to be well above 200kmph. Giving it a priority like Mum Rajdhani will take a heavy toll on timings of regular express trains. How much incremental speed its tilting mechanism permit on the curves falling in the route is still not clear. Hence the ongoing trials are still full of suspense but definitely are of paramount importance, as far as future of SHS train operation in IRly is concerned.
It would be nice if the video of inside and outside views of the talgo trial train with meaningful commentary is made and posted for the enrichment of persons working in railway field and railway enthusiasts.