1991 2001- 2003-2011 aeronautics afghanwar airlift airpilots airplanes airtankers(militaryscience) coldwar costeffectiveness costs designandconstruction equipment equipmentandsupplies evaluation history iraqwar jettransports kc-10(tankeraircraft) kc-135(tankeraircraft) maintenanceandrepair military officers operationalreadiness operationalreadiness(militaryscience) persiangulfwar procurement transportation unitedstates