Emergency Rocket Communications System
Emergency Rocket Communications System payload
Type	Intercontinental ballistic missile/Communications System
Place of origin	United States
Service history
In service	1963 (1963)–1968 (1968) (Blue Scout) 1968 (1968)–1991 (1991) (Minuteman II)
Used by	United States 510th Missile Squadron
Production history
Manufacturer	Boeing
Unit cost	US$7,000,000 (equivalent to $63,294,737 in 2024)
Specifications
Mass	78,000 pounds (35,000 kg)
Length	59 feet 9.5 inches (18.225 m)
Diameter	5 feet 6 inches (1.68 m) (1st stage)
Warhead	1 kW UHF Transmitter
Engine	Three solid-propellant rocket motors First stage –Thiokol TU-122 (M-55) Second stage –Aerojet-General SR-19-AJ-1 Third stage –Aerojet/Thiokol SR73-AJ/TC-1
Operational range	8,100 miles (13,000 km)
Flight altitude	700 miles (1,100 km)
Maximum speed	Approximately 15,000 miles per hour (Mach 20; 24,000 km/h; 6.7 km/s) (terminal phase)
Guidance system	Inertial
Launch platform	Silo

TheEmergency Rocket Communications System (ERCS) was designed to provide a reliable and survivable emergency communications method for theUnited States National Command Authority, using aUHF repeater placed atop aBlue Scout rocket orMinuteman IIintercontinental ballistic missile.^[1]: 34-37 ERCS was deactivated as a communication means whenPresident George H.W. Bush issued a message to stand downSIOP-committed bombers andMinuteman IIs on 27 September 1991. HeadquartersSAC was given approval by theJoint Chiefs of Staff to deactivate the 494L payloads beginning 1 October 1992.^[2] However, HeadquartersSAC believed it was inefficient and unnecessary to support ERCS past fiscal year 1991, and kept the accelerated deactivation schedule.

The mission of the Emergency Rocket Communications System was to provide assured communication toUnited States strategic forces in the event of a nuclear attack. ERCS was a rocket or missile that carried a UHF transmitter as a payload instead of a nuclear warhead. In the event of a nuclear attack, ERCS would launch the UHF transmitter intolow space to transmit anEmergency Action Message (EAM) toStrategic Air Command units.^[3][4][5][6]

The ERCS sorties had two possible trajectories, East and West, to inform SAC alert forces in the northern tier bases (i.e. Minot AFB, Fairchild AFB, Grand Forks AFB).^[7]

ERCS was deactivated and taken out of the inventory as other means of emergency communication (i.e. ISST andMilstar) came online.^[8]

ERCS was also known asProject 279 (Blue Scout version) andProject 494L (Minuteman version). Sources report that the Project 279 was also known as Project Beanstalk;^{[9][10]: 74-79} while the Minuteman system may have been designatedLEM-70A.^[11]

Using theDepartment of Defense'sJoint Electronics Type Designation System (JETDS), the system was designated asAN/DRC-8. Within JETDS, that designation represents the 8th design of an Army-Navy pilotless carrier two-way communications radio.

TheBlue Scout version of ERCS (Program 279) was deployed to three sites nearWisner,West Point, andTekamah, Nebraska. The Program 494L Minuteman version of ERCS was only deployed toWhiteman AFB,Missouri's351st Strategic Missile Wing, under the direct control of the510th Strategic Missile Squadron (later the510th Missile Squadron).

ERCS was a three part communications system composed of the following elements:

1. The five510th Strategic Missile SquadronLaunch Control Centers, which exercised primary control over the ERCS
2. TheMinuteman missiles configured with ERCS payloads that were capable of accepting a voice recorded message of up to 90 seconds in length
3. TheSACairborne command post (ABNCP)ALCC-equipped aircraft which served as an alternate ERCS control agency.^[7]

Interface with ERCS hardware was provided by three modes:

• A land line through ground grouping points (North Bend, Nebraska and Red Oak, Iowa) allowed the airborne command post interface with 494L equipment^[12]
• A UHF radio link through theLaunch Control Center to theLaunch Facility^[12]
• A direct radio interface to theLaunch Facility, through theAirborne Launch Control System^[12]

Headquarters Strategic Air Command had the ability to make inputs directly into the missile. The Numbered Air Forces could direct the missile crew to make the inputs. In the case of the airborne command post, inputs could be made directly into the missile and missile launch could be made from the aircraft.^[12]

Operational tests of the 494LMinuteman II ERCS were conducted byAir Force Systems Command andStrategic Air Command under the code nameGIANT MOON.Launch Control Facility Oscar-1A (LCF O-1A) and Launch Facility Zero Four (LF-04) atVandenberg AFB,California were modified in 1977 to perform ERCS-related test functions.

After the system was declassified, the ten ERCS sorties were powered down and removed from their launch facilities. During these power-down operations, the location of the sorties were:

TheOgden Air Materiel Area atHill AFB,Utah was made the Systems Support Manager in August 1963.^[15]

• 29 September 1961 – HQ USAF issues Specific Operational Requirement (SOR) 192, for ERCS (designated Program 279)
• 27 December 1961 – Interim configuration finalized of three rockets with 1 KW transmitters, stationed aroundOmaha,Nebraska; four sites with three rockets each
• 5 April 1962 – Amendment to SOR 192 to include two east coast ERCS complexes, based onCHROME DOME routes andSAC elements inEurope
• 21 September 1962 –SAC study recommends use ofMinuteman missile, to eliminate Program 279 and its proposed expansion
• 7 June 1962 –SAC proposes changes to SOR 192, such as using sixMinuteman missiles selected from among the flights of an operational wing; this was envisioned not to impair the alternative capability of substituting nuclear warheads should future circumstances warrant.
• 11 July 1962 – Program 279 attains Initial Operating Capability (IOC); UHF transmitter payloads attached to threeMER-6A Blue Scout rockets at three sites nearWisner,West Point, andTekamah,Nebraska
• 13 December 1966 – A Minuteman II launched from Vandenberg AFB, Calif. carried the first Minuteman ERCS payload into space for testing and evaluation^[16]
• 17 April 1967 – Third, and last, test of the ERCS using a Minuteman booster; Emergency Action Message was inserted into the transmitter from anALCS aircraft.
• 15 August 1967 – First Program 494L payload arrives atWhiteman AFB,Missouri^[17]
• 10 October 1967 – First two Program 494L ERCS payloads put on alert atWhiteman AFB,Missouri; IOC obtained for Program 494L ERCS^[16]
• 1 January 1968 – Full Operational Capability (FOC) obtained for Program 494L ERCS; Program 279 ERCS inactivated bySAC^[17]
• 23 October 1974 – ERCS test, designated GIANT MOON 6, launched from Vandenberg AFB. Test was monitored on two frequencies by ground facilities. PACOM at Hickam AFB maintained valid reception of the JCS WHITE DOT ONE message for 22 minutes and another message for 14 minutes^[18]: 341
• 27 September 1991 – PresidentGeorge H. W. Bush terminatedSAC's alert force operations, which included takingMinuteman II ICBMs (including ERCS sorties) off-alert.

^[5]

ERCS is mentioned inThe Dead Hand: The Untold Story of the Cold War Arms Race and its Dangerous Legacy by David Hoffman.^[19]

ERCS is mentioned inArc Light by Eric Harry.

• List of military electronics of the United States
• Dead Hand – Russia's version of ERCS, relaying launch codes instead of messages
• Post-Attack Command and Control System (PACCS)
• Airborne Launch Control System (ALCS)
• Ground Wave Emergency Network (GWEN)
• Minimum Essential Emergency Communications Network (MEECN)
• Survivable Low Frequency Communications System (SLFCS)
• Primary Alerting System (PAS)
• SAC Automated Command and Control System (SACCS)

• Media related toEmergency Rocket Communications System at Wikimedia Commons

• Nuclear warfare
• Telecommunications equipment of the Cold War
• United States nuclear command and control
• Military electronics of the United States
• Military radio systems of the United States

• Wikipedia articles incorporating text from the United States Air Force
• Articles with short description
• Short description is different from Wikidata
• Use dmy dates from December 2019
• Commons category link from Wikidata