Underway Replenishment Group (UNREP) Ships — Asbestos in Navy Combat Logistics Force Vessels

The US Navy’s combat logistics force (CLF) — the underway replenishment (UNREP) ships that sustained carrier battle groups at sea — included fleet oilers (AO/T-AO), ammunition ships (AE), stores ships (AF), combat stores ships (AFS), and fast combat support ships (AOE/AOR). These vessels sailed with carrier battle groups and conducted continuous underway replenishment operations transferring fuel, ammunition, aviation fuel, and provisions to battle group ships while both vessels were underway at sea. CLF ships built before the mid-1970s asbestos phase-down — the Neosho class AOs, Sacramento class AOEs, Suribachi and Kilauea class AEs, Mars class AFS vessels — carried asbestos insulation in their engineering plants and throughout their interior construction.

Steam Engineering Plants in CLF Vessels

CLF vessels from the WWII and Cold War era used steam propulsion with asbestos-insulated engineering plants:

• Fleet oiler fire rooms — AO class fleet oilers (Neosho class, Cimarron class) used steam propulsion with asbestos-insulated boilers and steam piping in their fire rooms consistent with their 1950s-1970s construction eras
• Fast combat support ships — the Sacramento class (AOE-1) fast combat support ships used steam propulsion with large-scale engineering plants to sustain their high-speed capability of following carrier battle groups at carrier speeds — with asbestos insulation in the Sacramento class 1960s-era engineering plant construction
• Ammunition ship engineering spaces — Suribachi and Kilauea class AE ammunition ships used steam propulsion with asbestos-insulated fire rooms and engine rooms in their 1956-1968 construction eras

Cargo Handling and Replenishment Systems

CLF ship cargo handling systems also contained asbestos-associated components:

• Cargo pump rooms — fuel transfer pump rooms aboard fleet oilers used asbestos-insulated steam-driven pump machinery and associated piping throughout the cargo pump system
• Cargo winch and UNREP gear machinery — the machinery driving UNREP transfer rigs and cargo handling equipment used steam or hydraulic power with asbestos-containing components in older machinery spaces

Continuous Operations During Battle Group Deployments

CLF ship engineering ratings stood continuous watch rotations throughout extended battle group deployments:

• UNREP operations were conducted repeatedly throughout each deployment — a carrier battle group might take on fuel every 2-3 days underway. CLF ship engineering departments maintained continuous steam plant operation at the power levels required to match carrier battle group speeds during approach and station-keeping throughout each UNREP operation
• Engineering ratings aboard CLF ships accumulated extended watch-standing hours in asbestos-insulated engineering spaces across sustained battle group deployments

VA Claims for CLF Ship Veterans

VA presumptive service connection under 38 CFR § 3.309(d) covers asbestos exposure aboard Navy auxiliary vessels. Engineering ratings who served in engineering billets aboard combat logistics force ships built before the mid-1970s asbestos phase-down and have since been diagnosed with mesothelioma, asbestosis, or asbestos-related lung cancer may qualify for VA disability benefits.

Source notes: equipment-manifest entries (where shown) are sourced from public-record BUSHIPS (Bureau of Ships) documentation, NARA archives, and the public asbestos litigation record. Manufacturer attributions link to documented asbestos-product histories on AsbestosIndex.com where available. Nothing on this page constitutes medical or legal advice.