The major aerodynamic wind-tunnel tests that span the time frame from the early Titan I vehicle developed in 1955 to the most recent Titan-family vehicle, the Titan IV solid rocket motor upgrade, last tested in 1996, are summarized. These tests cover all aspects of single- and multibodied aerodynamics including nozzle hinge moments, staging, vehicle forces and moments, dynamic and static pressure distributions, and launch facility impingement pressures. Angle of attack/side slip covers the range primarily from 0 to 10 deg and, in select cases, from 50 to 90 deg. Principal emphasis is placed on the ground tests affecting the predicted aerodynamic environment of the Titan IV launch vehicle. Significant conclusions drawn from various three-body wind-tunnel tests are presented. Nomenclature C A = drag coefficient Cl = rolling moment coefficient Cm = bending moment coefficient in the pitch plane C N = normal force coefficient in the pitch plane Cn = bending moment coefficient in the yaw plane CY = side force coefficient in the yaw plane α = pitch plane angle of attack β = yaw plane angle of side slip I. Introduction A HISTORY of the major aerodynamic wind-tunnel tests that were conducted for the Titan family of launch vehicles is contained herein. Particular emphasis is given to those tests used to describe the aerodynamic environment of the most recent configuration, the Titan IV (TIV) type 1 [with solid rocket motor (SRM)] and type 2 [with solid rocket motor upgrade (SRMU)] launch vehicles. The description of the external aerodynamic environment acting on