Executive Summary

Heritage assesses with high confidence that U.S. aircraft and surface naval platforms can be divided into four operational availability zones during a high-intensity Taiwan conflict scenario, with approximately two-thirds of the force available for deployment within the first 15 days of conflict onset. This assessment is based on structured extrapolation from historical surge timelines, current strategic mobility doctrine, and maintenance readiness data.

Forward-based forces located in Japan, Guam, and aboard Indo-Pacific-deployed vessels are very likely to be combat-ready between days 0–5, while surge-ready forces from Hawaii and the U.S. West Coast are likely to arrive between days 6–15. CONUS-based tactical aircraft and ships, requiring staging, refueling, and coordination, are assessed to become available between days 13–30 under moderate-to-high operational tempo.

Heritage judges that approximately 15–20 percent of U.S. aircraft and surface combatants are likely to remain non-deployable for extended periods throughout a 365-day high-intensity conflict. This estimate is logically inferred from GAO and RAND reporting on depot-level maintenance cycles, refueling constraints, and systemic readiness limitations observed during peacetime surge operations. This inference is key because if the non-deployable fraction is significantly lower due to accelerated wartime maintenance adaptation, total force availability in-theater would increase, especially in the second and third quarters of the conflict.

These assessments are derived from historical surge timelines and planning assumptions and do not reflect empirical wartime performance or results from validated simulation testing. As such, these estimates are subject to variation based on refueling lane availability, basing access, and diplomatic clearance outcomes.

Methodology

This assessment is structured using a four-part methodology framework designed to support simulation modeling of U.S. force deployment timelines in a high-intensity Taiwan conflict scenario.

Role. This analysis models the availability and deployment timing of U.S. Air Force, Navy, and joint force aircraft and surface combatants over a 365-day conflict timeline. The objective is to categorize deployable platforms into distinct operational availability zones—based on location, readiness, and transit capability—and estimate when they are likely to become combat-effective in-theater. The central aim is to derive scenario-specific force flow benchmarks that reflect logistical constraints, basing posture, and surge doctrine rather than assuming full-force presence at day 0.

Identifier. Platform availability across zones is tracked using:

• Platform location at conflict onset (e.g., Japan, Guam, Hawaii, CONUS).
• Transit time based on vessel steaming speeds, aircraft tanker ferry timelines, and mobility doctrine.
• Readiness state including forward-deployment status, refueling cycles, and depot-level maintenance constraints.
• Operational tempo assumptions, typically moderate-to-high surge.
• Non-deployable fraction, assumed at 15–20 percent due to depot-level constraints and systemic readiness limitations.

These indicators allow the model to project phased platform availability by theater entry date, simulating delays from staging, clearance, tanker capacity, and canal or basing bottlenecks.

Process. The model assigns each aircraft and ship to one of the four deployment zones based on its starting location and assumed readiness. Using historical data and strategic mobility doctrine, it estimates likely arrival windows:

• Zone 1: Forward-deployed assets available days 0–5.
• Zone 2: Surge-ready assets available days 6–15.
• Zone 3A: CONUS-based assets deployable by days 13–30.
• Zone 3B: Non-deployable platforms unavailable throughout the conflict.

Data. This modeling effort draws on a broad range of open-source, government, and think tank material including:

• Mobility Capabilities and Requirements Study (MCRS-18) and Joint Staff allocation manuals for deployment timelines and mobility constraints.
• GAO and RAND readiness studies on depot-level maintenance and surge shortfalls.
• CRS reports on shipbuilding and deployment cycles from U.S. ports.
• Official Navy and Air Force fact sheets on forward-deployment readiness, including 7th Fleet posture and Pacific Air Forces (PACAF) Agile Combat Employment (ACE) doctrine.

Primary Purpose of the Document

This report provides a structured methodology to model when and how much of the U.S. military force (aircraft and surface ships) would realistically become available for combat operations across a 365-day high-intensity conflict over Taiwan.

Key Judgments

Zone 1: Forward-Based (33 percent)

• Aircraft: Heritage judges that forward-deployed U.S. aircraft stationed in Japan, Guam, or aboard Indo-Pacific aircraft carriers are very likely to be combat-ready and available between day 0 and day 5 of conflict onset.
  • According to official U.S. Air Force documentation, PACAF units based in Japan and Guam routinely employ Agile Combat Employment (ACE), explicitly designed to enable rapid sortie generation and sustainment under high-threat conditions, thereby supporting rapid response timelines.1
  • Similarly, the U.S. Navy confirms that forward-deployed Carrier Air Wing 5 (CVW-5), operating from USS Ronald Reagan (CVN-76) at Yokosuka, maintains continuous high readiness levels, explicitly positioned to promptly execute combat operations when directed.2
• Ships: Naval vessels forward-stationed within the Indo-Pacific theater, predominantly within the 7th Fleet’s operational footprint. Heritage judges these vessels are very likely combat-ready and available between day 0 and day 5, based on documented forward-deployment practices.
  • According to official U.S. Navy documentation, the 7th Fleet maintains continuous forward-deployed naval forces in strategic locations such as Yokosuka and Sasebo, Japan. This posture significantly reduces response times by approximately 17 days compared to continental U.S.-based forces, enabling rapid operational deployment immediately upon crisis onset.3
  • Regularly conducted operational assessments, such as the “Ready for Sea Assessments,” ensure persistent readiness of these forward-deployed vessels, explicitly verifying their ability to quickly undertake combat operations.4

Zone 2: Intermediate Surge-Ready (33 percent)

• Aircraft: Assets located in Hawaii, Alaska, Diego Garcia, or the U.S. West Coast (NAS Lemoore, Travis AFB). Heritage assesses these platforms would likely enter the theater between day 6 and day 12 following conflict initiation, based on strategic mobility capabilities and documented logistical constraints.
  • Heritage assesses that fighter aircraft relying on tanker-supported ferry operations can typically cover long-range transits across the Indo-Pacific within 6–10 days, based on operational planning factors and the logistical constraints documented in the Department of Defense’s 2018 Mobility Capabilities and Requirements Study (MCRS-18). While the MCRS-18 does not publish specific transit timelines, it underscores the stress on the tanker fleet and the complexity of coordinating aerial refueling across global distances.5
  • Real-world deployments would likely experience delays due to refueling lane congestion, diplomatic clearances, and base availability. The Stimson Center’s analysis of Indo-Pacific logistics constraints notes that obtaining “overflight rights and transit passage from neutral countries” can add significant time, and that without Southeast Asian basing access, “the United States would have to fly combat missions out of a relatively small number of military runways.”⁶ RAND’s air base defense research further documents that Chinese missile threats to forward bases compound these logistics challenges.6
• Ships: Positioned in Hawaii, U.S. West Coast ports, or intermediate staging locations capable of accelerated deployment. Heritage assesses these vessels would likely enter the theater between day 6 and day 15 after conflict initiation, based on documented transit speeds and historical mobility data.
  • Heritage estimates surge deployments from Hawaii or West Coast ports would require approximately one to two weeks to reach the Western Pacific, based on standard naval transit speeds and historical deployment patterns. The Congressional Research Service’s analysis of Navy force structure addresses “warfighting response timelines” and “employment cycles” as key planning factors.7
  • The Stimson Center’s analysis of DOW mobility requirements notes that naval vessels transiting to the Indo-Pacific face the “tyranny of distance,” with transit times of “about a week” for carriers and submarines crossing the Pacific, and “15-to-30 days to move troops, equipment, and supplies by sea from the U.S. West Coast to ports in Australia, Diego Garcia, Guam, or Japan.” Exact timelines vary based on operational tempo, environmental conditions, and threat posture.8

Zone 3A: CONUS-Based, Deployable within 30 Days (17 percent)

• Aircraft: Continental U.S. installations hosting deployable aircraft requiring logistical coordination, staging, and tanker allocation. Heritage assesses these aircraft would likely arrive in-theater between day 13 and day 24 following conflict initiation. These timelines reflect ideal-case mobility assumptions and could shift substantially based on weather, basing access, or adversary interference. Naval vessels departing from East Coast or Gulf Coast ports are assessed to require 16–30 days, depending on transit route, Panama Canal availability, and underway replenishment support.
  • Heritage estimates tactical aircraft deployments from CONUS would require approximately two to three weeks under surge conditions, based on standard ferry operation planning factors including tanker scheduling, diplomatic clearance lead times, and intermediate staging requirements. Publicly available operational accounts document the complexity of such deployments: diplomatic clearances “are difficult to obtain, require long lead times, and are time-limited,” while competing requirements for ground refueling and maximum-on-ground constraints at staging bases further complicate rapid theater entry.9
  • Heritage assesses combatant commanders should anticipate aircraft force package arrivals from CONUS surge pools within approximately 12 to 24 days, based on planning factors including tanker availability, staging base capacity, and diplomatic clearance processing times. Air Force doctrine confirms that aerial refueling “extends the range and expedites the arrival of self-deploying aircraft, precluding the need for intermediate staging bases,” though actual transit times depend on operational circumstances and en route infrastructure availability.10
• Ships: East Coast-based or Gulf Coast-based naval vessels requiring Panama Canal transit or global circumnavigation. Heritage assesses these vessels would likely arrive in-theater between day 16 and day 30 following conflict initiation.11
  • Heritage estimates transit durations from East Coast or Gulf Coast naval bases to the Western Pacific theater would require between two to four weeks under optimal conditions, based on standard cruising speeds and routing factors. The Stimson Center’s analysis of Indo-Pacific logistics notes that sealift from “the U.S. West Coast to ports in Australia, Diego Garcia, Guam, or Japan” requires “15-to-30 days,” while vessels from Atlantic ports face additional routing considerations including Panama Canal availability or Suez transit. CRS reporting confirms that “employment cycles, crewing constructs, or operational tempo limits... affect peacetime presence or warfighting response timelines.”12
  • Heritage notes that actual transit times would vary based on underway replenishment availability, weather conditions, and canal throughput constraints. GAO assessments of Navy Combat Logistics Force capabilities confirm that underway replenishment “enables combatant ships to operate at sea almost indefinitely” but that escort vessels have limited unrefueled range—for example, DDG-51 destroyers have approximately 10 days endurance at 18 knots before requiring refueling. Recent analysis suggests that if the Panama Canal is unavailable, “up to 30 percent of [the] fleet could be delayed,” and forces in contested waters “may need to persist for 30-60 days without significant support as the fleet musters its assets.”13

Zone 3B: CONUS-Based, Non-Deployable (17 percent)

• Aircraft: Aircraft and naval vessels undergoing depot-level maintenance, institutional training, or force regeneration cycles. Heritage assesses these platforms would almost certainly remain non-deployable throughout the entire 365-day simulation period due to structural readiness constraints and maintenance timelines.14
  • Based on RAND Corporation’s analysis on force readiness, Heritage assesses approximately 15–20 percent of aircraft consistently remain unavailable for deployment due to depot-level maintenance, component shortages, and institutional training requirements, even under wartime surge conditions.15
  • GAO reporting documents systemic maintenance challenges affecting fleet readiness, though it does not quantify a specific percentage of vessels consistently unavailable. GAO found that from fiscal years 2014-2019, “the Navy was unable to complete scheduled ship maintenance on time for about 75 percent of the maintenance periods,” resulting in “over 33,700 more days in maintenance than expected.” The Navy’s deferred depot maintenance backlog totals nearly $1.8 billion, with surface ships accounting for the majority of deferrals. These persistent delays reduce the number of ships available for training or operations at any given time.16
• Ships: Platforms undergoing extended overhaul, depot-level maintenance, or nuclear refueling cycles. Heritage assesses these vessels would almost certainly remain structurally unavailable throughout the entire 365-day simulation period due to prolonged maintenance cycles and regeneration timelines.
  • Heritage assesses approximately 15–20 percent of the Navy’s surface vessels would remain structurally unavailable throughout a 365-day conflict period due to depot-level maintenance cycles and backlog constraints. GAO reporting documents that maintenance delays “are trending upwards,” with the Navy losing tens of thousands of operational days to delayed maintenance periods. GAO notes that “fewer than 40 percent of Navy ships completed availability repairs on time,” and that shipyard capacity constraints—including workforce shortages and aging infrastructure—limit the Navy’s ability to accelerate maintenance completion even under surge conditions.17
  • Nuclear-powered vessels face particularly lengthy unavailability periods during refueling and overhaul cycles. Refueling and Overhaul (ROH) typically requires one to two years for submarines, while Refueling and Complex Overhaul (RCOH) for aircraft carriers can take four to six years—with recent RCOHs (such as USS George Washington’s 2,117-day overhaul) exceeding planned timelines due to workforce constraints, supply chain disruptions, and unexpected repair requirements. CRS and RAND reporting confirm these cycles are scheduled at ship mid-life, meaning a portion of the nuclear fleet is consistently unavailable for operational deployment.18