ACIII economy could be a great concept, a big milestone and game changer for IR, if implemented properly.
(1) Economy ACIII should use layout of SL coaches to accommodate 80 paxs in LHB coach without the dreaded SMB.
(2) No concession of any kind should be permitted on these trains and in return the fare should be kept very low (about 1.5 times SL fare-without bedding & catering) at no profit no loss so that AC travel comes within the reach of common man. IR should ask for exemption from service...
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tax on AC economy class to keep fares low. The loss giving SL paxs should be tempted to travel in no-profit-no-loss economy AC class, so that the loss in pax segment shall be reduced substantially for IR. Once SL class paxs migrate to ACEcon, IR can operate large number of 160kmph+ Semi High Speed Trains on several routes in future.
(3) All Rajdhanis like BCT/HWH/PNBE etc should be followed by a JanRajdhani with large number of AC economy coaches. Large number of paxs shall avail the Raj prority and speed. Other routes for such trains are hot destinations like Mumbai-HWH/ADI/SC/SBC/MAS/LKO/JP/Jammu/ASR/TVC etc Kolkata-MAS/SC/ADI/GHY etc. In fact poorly performing Durontos should be replaced with such trains.
(4)24-25 degree C temp. is cool enough, lower temperature is uncomfortable. But the blower has to be strong enough to make paxs feel the cooling of AC.