WASHINGTON, Jan 24 (Reuters) - The U.S. military's chief medical officer for Iraq was among a group of 12 high-ranking soldiers killed on Saturday in a helicopter crash outside Baghdad, the Pentagon said on Wednesday. Col. Brian Allgood, 46, was an orthopedic surgeon serving as command surgeon in Iraq. He and 11 other officers, mostly combat support personnel, were on what defense officials said was likely an "orientation flight" ahead of the arrival of other soldiers. Defense officials, however, declined discuss the group's specific mission at the time of the crash. Army officials also declined to say why a dozen...