437th AMXS Airman enjoys cool job Published March 21, 2013 By Senior Airman Dennis Sloan Joint Base Charleston Public Affairs JOINT BASE CHARLESTON, S.C. -- Airman 1st Class Nicholas McCracken, 437th Aircraft Maintenance Squadron crew chief, performs several maintenance tasks on the C-17 Globemaster III, including liquid oxygen transfers. Liquid oxygen is used as a means of distributing breathable air to aircrew members and passengers above 10,000 feet above sea level. The C-17 can hold approximately 155 gallons of LOX. Click here for full slideshow