U.S. Air Force Staff Sgt. Brandon Serena and military working dog, Waldo, perform a working dog demonstration for a group of cadets from the Royal Canadian Air Force at Joint Base Charleston, S.C., March 16, 2010. The demonstration consisted of numerous scenarios, all of which ended with Waldo's teeth locking onto Sergeant Serena's protected arm. Throughout their one-day tour of Joint Base Charleston, the cadets toured multiple squadrons and a static C-17. Sergeant Serena is a military working dog handler with the 628th Security Forces Squadron. (U.S. Air Force photo/Airman 1st Class Lauren Main)

U.S. Air Force Staff Sgt. Christopher Simmons and Tech. Sgt. Leslie Bell speak to a group of Royal Canadian Air Force Cadets at the Field Training Detachment on Joint Base Charleston, S.C., March 16, 2010. The FTD is used to train pipeline-Airmen how to work on C-17s. During their tour, the cadets visited the training areas for the C-17 engine, tail and cockpit. Sergeant Simmons and Sergeant Bell are aircraft maintenance instructors with the 373rd Training Squadron based out of Sheppard AFB, Texas. (U.S. Air Force photo/Airman 1st Class Lauren Main)

U.S. Air Force Staff Sgt. Ramon Alexander, Staff Sgt. Brandon Serena and military working dog, Waldo, perform a working dog demonstration for a group of cadets from the Royal Canadian Air Force on Joint Base Charleston, S.C., March 16. The demonstration consisted of numerous scenarios, all of which ended with Waldo's teeth locking onto Sergeant Serena's protected arm. Throughout their one-day tour of Joint Base Charleston, the cadets toured multiple squadrons and a static C-17. Sergeant Serena is a military working dog handler with the 628th Security Forces Squadron. (U.S. Air Force photo/Airman 1st Class Lauren Main)

Royal Canadian Air Force Cadets look on as U.S. Air Force Staff Sgt. Brandon Serena and military working dog, Waldo, perform a working dog demonstration on Joint Base Charleston, S.C., March 16, 2010. The demonstration consisted of numerous scenarios, all of which ended with Waldo's teeth locking onto Sergeant Serena's protected arm. Throughout their one-day tour of Joint Base Charleston, the cadets toured multiple squadrons and a static C-17. Sergeant Serena is a military working dog handler with the 628th Security Forces Squadron. (U.S. Air Force photo/Airman 1st Class Lauren Main)

U.S. Air Force Tech. Sgt. Benjamin Massarelli speaks to a group of Royal Canadian Air Force Cadets at the Field Training Detachment on Joint Base Charleston, S.C., March 16, 2010. Sergeant Massarelli educated the cadets on the in's and out's of the C-17 “Globemaster III” engine during their one-day tour. Throughout their tour, the cadets stopped at many squadrons and had the opportunity to see a static C-17. Sergeant Massarelli is an aircraft maintenance instructor with the 373rd Training Squadron based out of Sheppard AFB, Texas. (U.S. Air Force photo/Airman 1st Class Lauren Main)

Royal Canadian Air Force Cadets board a static C-17 during a tour at Joint Base Charleston, S.C., March 16, 2010. The cadets drove 22 hours from London, Ontario, Canada, to learn about American military operations. During their tour of Joint Base Charleston, the cadets visited numerous base facilities and watched a demonstration of the military working dogs. (U.S. Air Force Photo/Airman 1st Class Lauren Main)

Royal Canadian Air Force cadets look on as U.S. Air Force Senior Airman Ken Connor demonstrates the modifiable capabilities of the C-17 cargo bay at Joint Base Charleston, S.C., March 16, 2010. The cadets drove 22 hours from London, Ontario, Canada, to learn about American military operations. During their tour of Joint Base Charleston, the cadets toured numerous base facilities and watched a demonstration of the military working dogs. Airman Connor is a load master with the 16th Airlift Squadron. (U.S. Air Force Photo/Airman 1st Class Lauren Main)