जिंदगी में शादी के अलावा ट्रेन में RAC ही एक ऐसी स्थिति है,जिसमें दो अजनबी साथ निभाने को मजबूर होते है। - Junaid

** ACC and AC3 are the only profitable class for IR. Rest all are giving losses.
** When ACDD was introduced, IR did the mistake of not passing any benefit of the economies of scale (120 seats per coach instead of conventional 68-75) by keeping the fares same as normal ACC. As a result ACDD turned out to be a failure.
** Had the benefits been passed on to passengers by keeping profit per coach of ACDD & ACC same, fares would have been substantially lower and a number of severe loss giving...
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non-AC seating paxs would have moved on to ACDD and given modest profits to IR. But IRwant huge profit in the name of AC travel.
** In that case a number of full length ACDD trains would have been operating across IR network and ACDD coaches could have been a part of standard intercity rake composition.