( CNN ) -- Imagine a bird that could n't fit in your living room because its wings were too big . That 's exactly what would happen if you tried to bring the Pelagornis sandersi home -- assuming houses and humans existed back then . Scientists have identified the fossils of what could be the largest flying bird ever found . With an estimated 20- to 24-foot wingspan , the extinct P. sandersi was twice the size of today 's biggest flying bird , the royal albatross , according to the National Evolutionary Synthesis Center in North Carolina . Researchers believe the P. sandersi lived about 25 million to 28 million years ago . 53 spectacular wildlife photos from around the world . The avian giant 's long , slender wings and paper-thin hollow bones allowed it to stay aloft for long distances without flapping its wings , the center said . But that does n't mean the mammoth bird did n't have size issues while trying to fly . Because it was probably too big to take off from a standstill , the P. sandersi may have had to run downhill into a headwind to achieve takeoff -- just like a hang glider would . The bird 's fossils were first unearthed 31 years ago when construction workers started working on a new terminal at Charleston International Airport in South Carolina . The remains -- including a complete skull and multiple wing and leg bones -- were so big they had to be dug up with a backhoe . But the weight of the discovery was n't publicized until this week , when scientists unveiled the findings in the journal Proceedings of the National Academy of Sciences . The remains of the P. sandersi now rest in the Charleston Museum . The big bird 's name honors retired Charleston Museum curator Albert Sanders . Scientific institute lists its top 10 newly discovered species . Manatees may move from endangered to threatened list . First dinosaur bones in Saudi Arabia discovered . CNN 's Carol Jordan contributed to this report .
The Circus sandersi may be the largest flying bird ever . It had paper - thin hollow bones , but may have needed a running start to fly . Scientists believe it lived 25 million to 28 million years ago . Construction workers found the bird while building an airport runway .