AIR-CONDITIONED COACHES IN INDIAN RAILWAYS
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When was air-conditioning introduced in IR?
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The North-Western Railway introduced air-conditioned stock in the late 1930's (the earliest was probably the Frontier Mail in 1936 or...
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1937). BBCI Railways also experimented with air-conditioning at about the same time. By the early 1950's, air-conditioning was available on several long-distance trains. For example, in 1952-53 there were air-conditioned services between Bombay and Howrah, Delhi and Madras (Grand Trunk Exp.), Bombay and Delhi, Bombay-Amritsar (Frontier Mail), Bombay-Viramgam (Saurashtra Mail), and Bombay-Ahmedabad (Gujarat Mail).
These all used AC units that were mounted beneath the coach body (underslung), interconnected by pipes. Self-contained roof-mounted units appeared much later (1980's?).
The first fully air-conditioned train was introduced in 1956 between Howrah and Delhi. Popularly known as the AC Express, it ran on the Grand Chord; later there were two, one running on the Grand Chord and the other on the Main Line. Another train popularly known as the AC Express was the Dakshin Exp. between Madras and New Delhi in the 1960s.
AC Chair Car stock was introduced around 1955. Until about 1979, air-conditioning was available only in these and in AC First Class cars. Around 1979 the first two-tier AC coaches were introduced. The first 3-tier AC coaches were introduced in 1993 (RCF) and used on the Howrah Rajdhani via Patna. (The first such coach was ER 2301A, later changed to ER 94101A.) The first 60 or so of the three-tier AC coaches had 67 berths each, while all later ones have 64 berths. The LHB coaches introduced in recent years has a capacity of 72 berths
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