February 02, 2015: The visit of U.S. President Barack Obama definitely provided a push to pending Indo-US defence deals, but time may be of essence for two crucial contracts of the Indian Air Force. Deals for 15 Boeing CH-47F Chinook heavy lift helicopters and 22 Boeing AH-64D Apache Block III (some Longbow) attack helicopters could rise in cost after March 31, with the validity of bids coming into play. The Chinook and Apache defeated the Russian Mi-26T and Mi-28NE respectively in extended competitions that finally saw the American machines emerge on top. Negotiations on both deals have been largely complete for two years, with final tweaking underway to ready signable agreements between the Indian MoD and Boeing Defense. The IAF has been waiting anxiously for both deals. Its heavylift helicopter capability is whittled down to just three choppers, currently being deployed for logistical work in the upper reaches of flood devastated Uttarakhand, specifically Kedarnath. While the IAF's Mi-35 attack helicopters were displayed at this year's Republic Day Parade, those choppers also suffer from availability issues.