TKD WDP-4B "प्रतीक" - रंग ऐसा कि हर किसी को प्यार हो जाए - Anubhav Kashyap

In order to maintain dignity of particular variants and ensure optimum occupancy of a particular category of train, there should be some speed criteria, without satisfying which that particular category of train can't be run ( exception to geographic/administrative constraints be allowed)
Vande Bharat : 80km/h avg speed and at least 1 tier1- tier2 city en route
Shatabdi/Tejas : 65+ avg speed.
Jan...
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shatabdi : 55+ avg speed.
Rajdhani : 60+ avg speed/ capital to capital
Duronto/Sampark kranti : 55+ avg speed
As given above, some exceptions be allowed owing to altitude/soil/terrain constraints.
The likes of bsp ngp VB be converted to jan shatabdi
dli kgm/rmr sk and shatabdi converted to Intercity