The E-3 Sentry is an airborne warning and control system (AWACS) aircraft that provides all-weather surveillance, command, control and communications needed by commanders of U.S. and NATO air defense forces. As proven in Desert Storm, it is the premier air-battle command and control aircraft in the world today.
The E-3 Sentry is a modified Boeing 707/320 commercial airframe with a rotating radar dome. The dome is 30 feet in diameter, six feet thick, and is held 11 feet above the fuselage by two struts. It contains a radar subsystem and an identification friend or foe (IFF) subsystem that permits surveillance from the Earth's surface up into the stratisphere, over land or water. The radar has a range of more than 200 miles (320 kilometers) for low-flying targets, and farther for aerospace vehicles flying at medium to high altitudes. It can look down to detect, identify and track enemy and friendly low-flying aircraft by eliminating ground cluster returns that confuse other radar systems.
The entire E-3 fleet is going through the single largest upgrade in history. The upgrade, known as the Block 30/35 Modification Program, includes four enhancements.
- Electronic Support Measure: Passive detection, an electronic surveillance capability to detect and identify air and surface-based emitters. ESM will augment present on-board sensors.
- Joint Tactical Information Distribution System: Upgrade provides secure, anti-jam communication for information distribution, position location and identification capabilities.
- Computer Upgrade: Increases the memory capability; the computer will accommodate JTIDS, ESM improvements and future enhancements.
- Global Positioning System: Satellite-based positioning will provide precise global navigation capability. The first aircraft upgrade was completed in October 1995. The estimated completion for the entire fleet of 32 aircraft is 2001.
Other major subsystems in the E-3 are navigation, communications and computers (data processing). Console operators perform surveillance, identification, weapons control, battle management and communications functions.
The radar and computer subsystems on the E-3 Sentry can gather and present broad and detailed battlefield information. Data is collected as events occur. This includes position and tracking information on enemy aircraft and ships, and location and status of friendly aircraft, naval vessels and ground troops. The information can be sent to major command and control centers in rear areas or aboard ships. In time of crisis, this data can be forwarded to the National Command Authorities in the United States.
In support of air-to-ground operations, the E-3 Sentry can provide direct information needed for interdiction, reconnaisance, airlift and close-air support for friendly ground forces. It can also provide information for commanders of air operations to gain and maintain control of the air battle.
As an air defense system, E-3's can detect, identify and track airborne enemy forces far from the boundaries of the United States or NATO countries. It can direct fighter-interceptor aircraft to these enemy targets.
Experience has proven the E-3 Sentry can respond quickly and effectively to a crisis and support worldwide military deployment operations. Its jam-resistant systems have performed missions while experiencing heavy electronic countermeasures.
With its mobility as an airborne warning control system, the Sentry has a greater chance of surviving in warfare than a fixed, ground-based radar system. Among other things, the E-3's flight path can quickly be changed according to mission and survival requirements.
The E-3 Sentry can fly a mission profile for more than 11 hours without refueling. Its range and on-station time can be increased through inflight refueling and the use of an on-board crew rest area.
The aircraft can be used as a surveillance asset in support of other government agencies during counterdrug operations. U.S. Customs Service officers may fly aboard the E-3 Sentry on precoordinated missions to detect smuggling activities.
Engineering, test and evaluation began on the first E-3 Sentry in October 1975. The Airborne Warning and Control Wing (now Air Control Wing, Tinker Air Force Base, Okla.) received the first E-3's in March 1977.
Pacific Air Forces has four E-3 Sentries assigned to the 961st AWAC Squadron, Kadena Air Base, Japan, and the 962nd AWAC Squadron, Elmendorf Air Force Base, Alaska. The remaining aircraft are assigned to the 552nd Air Control Wing.
E-3 Sentry aircraft were among the first to deploy during Operation Desert Shield where they immediately established an around-the-clock radar screen to defend against Iraqi aggression. During Desert Storm, E-3s flew more than 400 missions and logged more than 5,000 hours of on-station time. They provided radar surveillance and control to more than 120,000 coalition sorties. In addition to providing senior leadership with time-critical information on the actions of enemy forces, E-3 controllers assisted in 38 of the 40 air-to-air kills recorded during the conflict.
For the first time in the history of aerial warfare, an entire air war has been recorded. This was due to the data collection capability of the E-3 radar and computer subsystems.
Primary Function: Airborne surveillance, command, control and communications
Builder: Boeing Aerospace Co.
Power Plant: Four Pratt and Whitney TF-33-PW-100A turbofan engines
Thrust: 21,000 pounds (9,450 kilograms) each engine
Length: 145 feet, 6 inches (44 meters)
Wingspan: 130 feet, 10 inches (39.7 meters)
Height: 41 feet, 4 inches (12.5 meters)
Rotodome: 30 feet in diameter (9.1 meters), 6 feet thick (1.8 meters), mounted 11 feet (3.33 meters) above fuselage.
Speed: Optimum cruise, 360 mph (Mach 0.48)
Ceiling: Above 29,000 feet (8,788 meters)
Maximum Takeoff Weight: 347,000 pounds (156,150 kilograms)
Endurance: More than 11 hours (unrefueled)
Unit Cost: Approximately $270 million
Crew: Flight crew of four plus mission crew of 13-19 specialists (varies according to mission)
Date Deployed: March 1977
Airframe: Modified Boeing 707-320B
Flight time: 8.5 hours unrefueled/22.0 hours refueled
System operational 1.0 hours after take off
Operating Altitude: 29,000 to 31,000 feet
Standard crew size: 19 to 25 members
Radar: Pulse Doppler with 200+ NM detection
360 degree coverage
Comm: VHF, UHF, HF, SATCOM, Datalink