USAF Mobile Water Supply (MWS) Fire Practice Test

Maximizing intake flow comes from giving water multiple parallel paths to reach the fill point. The best setup uses a manifold that splits the source into several hoses, so the flow isn’t forced through a single line and its friction losses. In this configuration, water is fed through one large-diameter hose and two medium-diameter hoses via a manifold, creating three parallel paths. This increases the total cross-sectional area available for flow and reduces the overall resistance seen by the fill connection, allowing a higher combined flow rate into the 4-inch direct fill. Adding an inline gate valve would introduce unnecessary resistance, decreasing flow. A single large hose or just two large hoses in parallel still limits flow to the capacity of those paths and doesn’t make use of the additional parallel routes a manifold provides. The manifold arrangement blends the strengths of multiple hoses to deliver the greatest possible intake rate for the 4-inch fill connection.