Kovai for a long time was probably the fastest non premium Intercity super fast trains in India. The train was faster than the much famed Karnavati, Gomti, DQ and even SR's own Vaigai and Brindavan. Lalbagh when introduced was the only train matching Kovai's speed of over 66Kmph. The train took less than 7.30mts between MAS and CBE and return. Infact back then there were talks that Kovai will be faster after the Irugur section of the line becomes a double line.
But what we have seen is a drastic deterioration of speed primarily due to poor handling of this train by SR. Just like how they destroyed Brindavan and force fed the highly uncomfortable Double Decker in MAS...
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SBC route, they are spoiling the speed and punctuality of Kovai to force in Shatabdi.
Southern Railway off late have slowed down many trains including Shatabdi, Rajdhani and Duronto to show off punctuality. This is indeed a very cunning and ill advised game played by SR at the expense of the common Man.
Because of the archaic 55kmph rule, 90% of trains qualify for SF status through which Railways is making money, added to that are Tatkal, premium tatkal, suvidha, premium etc etc categories. Common people are spending more money but has comfort increased? Has speed increased? No!
What is the point in introducing 1 fast train somewhere in India while many trains run slower than what they used to Run many years back. We blame ot on increased traffic, population increase etc. But if railways is able to maintain priority and run trains at much higher speeds in some of the busiest corridors in India, why not in SR.