Boeing Co submitted its bid today to build the next generation of US Air Force tankers, joining the European firm EADS in the competition to win the the lucrative contract, according to dpa. Boeing turned over its 8,000 page-proposal to the Pentagon, one day after EADS, the Paris- and Munich-based parent company of Airbus, sent in its bid of an equal length. The aerospace giants are in a bitter competition for the 35-billion-dollar contract to build 179 aerial refuellers dubbed the KC-X. Both firms proclaimed their proposals meet all of the requirements outlined by the Air Force and say their respective bids offer a better deal to the US taxpayer and will create tens of thousands of jobs. "As the only company in this competition with rich experience in developing and manufacturing derivative aircraft for the warfighter, Boeing brings the talent and resources of our existing team and facilities to fully meet the requirements of the US Air Force," Jim Albaugh, president and CEO of Boeing Commercial Airplanes, said. Boeing's proposal is based on its 767 passenger plane built near Seattle, Washington, and EADS is proposing to build an assembly plant in Mobile, Alabama. "We're proud of our offering, which is the only one in this competition that is flying and refuelling today," said Ralph Crosby, the chairman of EADS North America. He added his firm's plane provides "superior capabilities." Friday was the due date for the firms to submit their bids. The Pentagon extended by 60 days at the request of EADS, which needed more time after its US-based partner, Northrop Grumman, dropped out. The Pentagon wanted to avoid having Boeing as the sole bidder for the contract. Boeing and EADS, which stands for the European Aeronautic Defence and Space Company, have been sparring over the contract for years. The Northrop-EADS partnership had originally won the bid, but Boeing lodged a protest with a congressional agency that determined in June 2008 that errors were made in the process, prompting the Pentagon to cancel the award and reopen the bidding earlier this year. The contract to replace the ageing fleet of KC-135s has been a sensitive issue internationally and in the United States. Boeing supporters in Congress have said that awarding the contract to a foreign-based firm would cost Americans jobs. The tanker programme could reach more than 100 billion dollars in contracts in later stages of the programme to replace the KC-135s. The Air Force has been plagued with problems in its long-standing effort to procure the next generation of tankers.