SHEPPARD AIR FORCE BASE, Texas (AFNS) -- More than 50 years of dependable service is a lot to ask, especially from a tool used to train thousands of people in a critical and sometimes dangerous business. But as men and women in the U.S. Air Force said farewell to the T-37 Tweet July 31, they did so knowing they got all they asked for and more from the venerable training aircraft. Among those who came to Sheppard to usher out the end of an era and welcome in a new technological advancement in undergraduate pilot training was Gen. Donald J....