	Introduction

The fleet of manned aircraft that accomplishes the Department of Defense's (DOD's) Command and Control (C2) and Intelligence, Surveillance, and Reconnaissance (ISR) missions for the joint military community (E-8, E-3, RC-135, WC-135, OC-135, and E-6) is primarily based on Boeing 707 aircraft procured from the 1960s to the early 1990s. As the age of these legacy C2ISR aircraft increases, understanding the Air Force and Navy modernization and recapitalization plans is likely important for Congress. This report examines the Air Force's and Navy's current sustainment, modernization, and recapitalization efforts for these Boeing 707-based aircraft. This report addresses potential congressional oversight and appropriations concerns for the sustainment, modernization, and recapitalization of the DOD's Boeing 707-based legacy C2ISR aircraft fleet. It does not address options for recapitalization currently being offered by industry to other countries. Congress has the authority to approve, reject, or modify Air Force and Navy funding requests for C2ISR aircraft sustainment, modernization, and recapitalization, as well as maintain oversight of the nation's C2ISR requirements and capabilities. Congress's decisions on appropriations for the C2ISR force could impact the nation's C2ISR capabilities and have additional consequences for the U.S. aerospace industry. Another issue for Congress is DOD, Air Force, and Navy priorities for sustainment, modernization, and recapitalization efforts. Additionally, potentially shifting some of the legacy C2ISR missions to remotely piloted aircraft may affect recapitalization efforts. E-8C Joint Surveillance Targeting Attack Radar System (Joint STARS or JSTARS)

The E-8C JSTARS is an airborne battle management, command and control, intelligence, surveillance, and reconnaissance platform. E-3 Sentry (AWACS)35

The E-3 Sentry is an airborne warning and control system (AWACS) aircraft with integrated command and control battle management (C2BM), surveillance, target detection, and tracking. RC-135V/W RIVET JOINT43

The RC-135V/W RIVET JOINT reconnaissance aircraft supports theater and national level leaders with near real time on-scene intelligence collection, analysis, and dissemination capabilities. The COMBAT SENT locates, identifies, collects, and examines foreign military land, naval, and airborne radar signals, providing strategic analysis. Information garnered from the data helps determine detailed operating characteristics and capabilities of foreign systems. WC-135 Constant Phoenix50

The WC-135 Constant Phoenix atmospheric collection aircraft supports national leaders by collecting particulate and gaseous effluents and debris to detect nuclear weapons testing and detonations from accessible regions of the atmosphere. OC-135B Open Skies53

The OC-135B Open Skies Observation Aircraft supports the Open Skies Treaty. The aircraft flies unarmed observation flights over participating parties of the treaty. E-6B Mercury57

The E-6B Mercury is communications relay and strategic airborne command post aircraft. Issues for Congress63

		Potential for Shortfall in C2ISR Capabilities

As the current C2ISR force continues to age and shrink, and development of replacements for some aircraft begins, a potential oversight issue for Congress is whether current DOD plans to sustain, modernize, and/or recapitalize the Boeing 707-based C2ISR fleet may result in a shortfall in the nation's C2ISR capabilities. Will modernization efforts allow for delayed recapitalization efforts? Implications of Modernization and Recapitalization on Basing

Another potential oversight issue is the possible implications of reduced legacy C2ISR aircraft sustainment and modernization, and subsequent diminishing numbers of airframes, on any future rounds of base realignment and closure (BRAC). Industrial Base Concerns Associated with C2ISR Sustainment

Another potential oversight issue is the ability of the nation's industrial base to sustain the legacy C2ISR aircraft force. The central issue is how much Congress should consider appropriating for the continued sustainment and modernization of these aircraft compared to funding for recapitalization of these missions to new aircraft. Pertinent to the discussion is the potential for a shortfall in the nation's C2ISR capabilities if Congress or the DOD chooses to minimize funding for sustainment and upgrades that would keep the weapon systems viable until they are recapitalized.
The fleet of manned aircraft accomplishing the Department of Defense's (DOD's) Command and Control (C2) and Intelligence, Surveillance, and Reconnaissance (ISR) missions for the joint military community (E-8, E-3, RC-135, WC-135, OC-135, and E-6) is primarily based on Boeing 707 aircraft procured from the 1960s to the early 1990s. As the age of these legacy C2ISR aircraft increases, understanding the Air Force and Navy modernization and recapitalization plans is likely important for Congress. This report examines the Air Force's and Navy's current sustainment, modernization, and recapitalization efforts for these Boeing 707-based aircraft, and issues Congress may take into account when considering appropriating funds for continued sustainment and modernization of these aircraft versus funding for recapitalization of these missions to new aircraft.
This report addresses potential congressional oversight and appropriations concerns for the sustainment, modernization, and recapitalization of the DOD's Boeing 707-based legacy C2ISR aircraft fleet. It does not address options for recapitalization currently being offered by industry to other countries. Congress has the authority to approve, reject, or modify Air Force and Navy funding requests for C2ISR aircraft sustainment, modernization, and recapitalization, as well as oversight of the nation's C2ISR requirements and capabilities. Congress's decisions on appropriations for the C2ISR force could impact the nation's C2ISR capabilities and have additional consequences for the U.S. aerospace industry.
The starting point for Congress's debate on legacy C2ISR sustainment, modernization, and recapitalization is the existing Boeing 707-based C2ISR fleet consisting of 89 operational aircraft, which includes
16 E-8C Joint Surveillance Targeting Attack Radar System (JSTARS) aircraft providing airborne battle management, command and control, intelligence, surveillance, and reconnaissance; 31 E-3 Sentry Airborne Warning and Control (AWACS) aircraft with integrated command and control battle management (C2BM), surveillance, target detection, and tracking; 17 RC-135V/W RIVET JOINT aircraft supporting theater and national level forces with near real time on-scene intelligence collection, analysis, and dissemination capabilities; 2 RC-135U COMBAT SENT aircraft that locate and identify foreign military land, naval, and airborne radar signals to determine detailed operating characteristics and capabilities of those systems; 3 RC-135S COBRA BALL aircraft that collect optical and electronic data on ballistic missile targets; 2 WC-135 Constant Phoenix atmospheric collection aircraft that collect particulate and gaseous effluents and debris from accessible regions of the atmosphere supporting the Limited Nuclear Test Ban Treaty of 1963; 2 OC-135B Open Skies aircraft that perform unarmed observation flights over participating parties of the Open Skies Treaty, and 16 E-6B Mercury communications relay and strategic airborne command post aircraft.
Potential congressional oversight and appropriations concerns for the sustainment, modernization, and/or recapitalization of the DOD's Boeing 707-based legacy C2ISR aircraft fleet include
a potential shortfall in C2ISR capabilities if there is a funding gap for sustainment and upgrades that would keep the weapon systems viable until they are recapitalized; ascertaining DOD, Air Force, and Navy priorities for sustainment, modernization, and recapitalization; determining if modernization efforts allow for delayed recapitalization efforts; consideration of shifting some of the legacy C2ISR missions to remotely piloted aircraft; the potential implications of reduced legacy C2ISR aircraft sustainment and modernization, and subsequent diminishing numbers of airframes on any future rounds of base realignment and closure efforts; and the ability of the nation's industrial base to sustain the legacy C2ISR aircraft force.