Few aircraft in history are as feared, loved, and debated as the A-10 Warthog. The A-10 Thunderbolt II—better known as the “Warthog”—was built to survive and to save lives on the ground. Originally conceived as a Cold War tank destroyer, it went under appreciated for years, only to become a sensation on the battlefields of Iraq and Afghanistan. Once derided in the 1980s as an “ugly duckling,” it ultimately emerged as a guardian angel for thousands of American soldiers on the ground. Why did the GAU-8 Avenger’s unmistakable “BRRRT” strike fear into enemies? How could the Warthog keep flying through damage that would destroy other jets? And why did the Air Force recently retire the Warthog, despite its cult status and fierce opposition from the Army?