Air India is seeing a gain in rail minister Suresh Prabhu 's surge-pricing pain. The national carrier on Saturday brought out full page ads , selling unsold seats on its metro flights at Rajdhani II fares four hours before departure time.The ad, featuring the legendary Maharaja, claimed cheaper Air India spot fares than Rajdhani flexi fares, taking potshot at Prabhu's pricing move panned by train travellers.Air India, in its website, offered the spot fares till September 30 on all Rajdhani Express routes on the price of the train’s first and second class AC ticket.As per Prabhu's surge pricing model, the base fare will go up by 10% for every 10% seats sold, with a cap of 1.5 times the base fare. The airline will follow regular Rajdhani AC II fares.For instance, the airline will charge Rs 2,870, Rs 2,990 and Rs 4,090 for last-minute unsold seats on flights from Delhi to Mumbai Kolkata and Bengaluru respectively. “The new Rajdhani AC II fares on these routes can be as high as Rs 4,054; Rs 4,090 and Rs 5,626 respectively. The difference is stark,“ an AI official told TOI.Rajdhani AC II fares are available on AI flights on 11 important metro routes, including Delhi to Mumbai, Chennai , Bengaluru, Kolkata and Ahmedabad . While AI fares are subject to availability, almost all Indian carriers are offering hefty discounts due to the entry of new players and all airlines, old and new, are ordering and inducting aircraft by the dozen. On Thursday night, travel portals were showing fares starting from Rs 2,800 for a Delhi-Mumbai flight on Friday -the start of a long festive weekend.The travel industry believes this could be the start of a major boost for airlines. “The recent surge pricing announcement in railway fares will change the perception of the average traveller. Our data suggests that there is a minor difference between railway and air fare. This development will boost air travel as the air fare is now competitive and cheaper than AC II and is almost the same as AC III,“ travel portal Yatra president Sharat Dhall said. “For travellers making advance bookings, this is a favourable time to book as airfares are highly unlikely to increase.“A senior AI official said, “The government wants flying to be as affordable as viable. That is the reason why we decided to offer our unsold seats on metro routes at Rajdhani AC II fares within four hours of departure of these flights. AI chairman Ashwani Lohani (who has come from railways) has decided not to opt for surge pricing and stick to the lowest AC II fares on the routes as originally planned.“