IndiGo, India's biggest airline, will buy 20 Airbus A321neo jets instead of smaller A320neos as planned, as carriers increasingly opt for medium-sized planes that can transport more passengers and fly longer distances."IndiGo has converted 20 A320neo aircraft into A321neo," the company said, without providing further details.The carrier's previous deliveries of A320neos were delayed due to glitches found in engines built by Pratt & Whitney. IndiGo has ordered a total of 430 A320neos, with the first aircraft handed over in March. The Airbus spokesman Justin Dubon would not comment on specific orders, but saidthe France-based company works with customers "continually" to "meet their evolving fleet needs."Carriers in markets with limited infrastructure are buying bigger planes to improve their profitability, especially on local routes where airlines are struggling to find enough landing and parking slots. While bigger planes are more expensive, large orders come with a discount. At current list prices, 20 Airbus A321neo jets would cost about $2.5bn, compared with $2.1bn for the A320neo.The A320neo accommodates as many as 189 passengers, while the A321neo carries as many as 240. Both are single-aisle planes."The market is clearly upsizing and in 2016 some 45 per cent of our single-aisle deliveries will be A321," Mr Dubon said. "This trend is set to continue."IndiGo's order switch is not yet reflected in the Airbus order book that's published on its website. The airline is operated by InterGlobe [email protected] The National's Business section on TwitterThe post India's largest carrier to upgrade 20-plane Airbus order appeared first on UAE Business Directory - TotalUAE.com.