The Lost Command — Vaughn Heppner

Earth needs a miracle. Out of the Beyond invade the New Men, stronger, faster and smarter than the old. Star Watch sends a massed battle fleet to stop them. It's a disaster. Admiral Fletcher barely escapes annihilation by heading at sub-light speed for a nearby star system. His battered ships are running out of food, fuel and missiles. He knows the New Men will use jump gates, waiting for him six months from now at his destination. Star Watch Command frantically searches for a way to rescue the vessels. Earth has an ancient alien starship in the Oort cloud, with a suspicious AI refusing to cooperate with the scientists. The vessel has powerful weapons -- if anyone could figure out how to make them work after ten thousand years. Star Watch summons Captain Maddox, an unorthodox Intelligence officer who makes things happen. He is given command of Victory and told to fix the ancient weapons, rescue Fletcher's ships and help them battle home again.