With the development of large diameter unmanned underwater vehicles, designers have optimized internal volumes and arrangeable area by departing from the traditional body of revolution submersible hull forms. Further, mission flexibility and cost efficiency may be enhanced through the use of reconfigurable payload/mission packages stored external to the platform envelope. In this study, we examine the impact to deep water performance of the submersible hullform when appended with several large (2.3% of the total platform envelope volume, each) longitudinal pods. Following a design study, three different pod stern geometries (blunt parabolic, elongated parabolic, and 1-D taper or “flat tail”) are evaluated in each of two different appended configurations (two pods, and four pods). A final pod design (with the most streamlined stern profile) is selected based on resistance performance through tow tank model testing at 1/8th scale. Measurements of the form drag coefficient in the different configurations of the several pod designs are then used in a Froude Expansion to estimate the total powering and resistance for the platform at depth. Additional performance analyses are conducted using wind tunnel model testing at 1/16th scale including the impact of pod appendages on resistance, static pitch moment, and the effectiveness of bow control surfaces. Of particular interest is the impact to estimates of the maneuvering matrix coefficients and the dynamic stability and maneuverability of the platform.