The need for a survivable SAC Command Post as a key component of adequate US deterrence and security meshed well with the change in US nuclear policy. The policy changed from massive retaliation to flexible response upon control of America's nuclear strike force. This during the trans and early post Single Integrated Operational Plan (SIOP) periods. The one likely survivable candidate was an airborne platform. Plans had been under consideration by SAC since late 1958 to test an airborne command post variant of the KC-135, with a desired operational capability by 1960.
Like its sibling, the commercial Boeing 707 jet airliner, the KC-135 was derived from the Boeing 367-80 jet transport "proof of concept" demonstrator, which was commonly called the "Dash-80". The KC-135 is similar in appearance to the 707, but has a narrower fuselage and is shorter than the 707. The KC-135 predates the 707, and is structurally quite different from the civilian airliner. Boeing gave the future KC-135 tanker the initial designation Model 717.
On 26 May 1960, the first KC-135A (58-0022) began modification to an Airborne Command Post (ABNCP) configuration, and operational tests started two months later at Offutt AFB, Nebraska. Five modified KC-135As assigned to the 34th AREFS (Air Refueling Squadron) were placed on ground alert and periodically tested to determine their ability to take off within 15 minutes. Once airborne, they would serve as an alternate CP, assuming primary control over the SAC combat force if an enemy attack destroyed the underground SAC facility at Offutt AFB and the other Numbered Air Force (NAF) CP's. On board each flight was a senior SAC officer (initially a Colonel and eventually a Brigadier General as a minimum) known as the Airborne Emergency Action Officer (AEAO). The AEAO would take over command of the SIOP forces in the event communications were lost with the National Command Authority (NCA) and SAC headquarters.
After six months, the testing was deemed successful. CINCSAC General Thomas S. Power hailed the testing as "conclusive proof" of the effectiveness of an ABNCP. The decision was then made to expand the program. Additional KC-135As were converted into ABNCP's for use as back-ups to the primary ABNCP.
While the nuclear threat was even more concerning throughout Europe, the 7120th ACCS was activated in 1960 at Châteauroux-Déols Air Base at the Chateauoux-Centre Airport, Indre, France. Equipped with modified C-118G's (Douglas DC-6 piston-powered transports) this operation was named Silk Purse. In early 1961 along with the Silk Purse Control Group, Operation Silk Purse began flying airborne nuclear command and control for the European theater of operations. This to assume authority if the US European Command (EUCOM) Headquarters at the French Army base Camp des Loges, west of Paris, France was destroyed or rendered inoperative.
In January of 1961 shortly after his inauguration, President Kennedy directed that one of SAC's new ABNCP's begin flying continuous operations. On 3 February 1961, the KC-135A Airborne Command Post (ABNCP) began flying continuous airborne operations, with additional back-up aircraft on 15-minute ground alert. The KC-135A ABNCP sortie, dubbed "Looking Glass", was airborne safely and continuously from 3 February 1961 to 24 July 1990.
During 1962 the PACCS network underwent several major reorganizations, expanding to include three KC-135A Auxiliary Airborne Command Post (AUXCP) units and four support squadrons. Beginning in April 1962 AUXCPs were assigned to Air Refueling Squadrons based at NAF Headquarters (HQ's) AFB's. The Central AUXCP (CENTAUXCP) 2nd AF HQ's at Barksdale AFB, Louisiana was assigned to the 913th AREFS, the Eastern AUXCP (EASTAUXCP) 8th AF HQ's at Westover AFB, Massachusetts was assigned to the 99th AFRES and the Western AUXCP (WESTAUXCP) 15th AF HQ's at March AFB, California was assigned to the 22nd AREFS. The AUXCPs were configured the same as the primary ABNCP and could replace it, if needed.
Also in 1962, 35 obsolescent B-47E's were modified as electronic communications aircraft under the designation EB-47L. The EB-47L's, equipped with AN/ARC-89 (V) UHF transmitters and receivers, were operated by four newly formed PACCS Squadrons. These aircraft served as airborne radio-relay stations between other PACCS aircraft or ground stations during and after a nuclear attack. EB-47L's could have relayed SAC "go-code" messages via UHF "Line-of-Sight" communications should other methods be disabled or destroyed.
On 20 July 1962, shortly before the Cuban Missile Crisis, SAC activated the EB-47L radio-relay operation "Pipe Cleaner" at the secretive 4362nd PACCS Squadron, assigned to the 307th Bomb Wing at Lincoln AFB, Nebraska. Ten aircraft flew the operation "Pipe Cleaner" mission from Lincoln AFB starting in August 1962. Three other newly formed PACCS squadrons based out of Mountain Home AFB, Idaho, Lockborne AFB, Ohio and Plattsburgh AFB, New York, EB-47Ls also began flying operation "Pipe Cleaner" radio-relay missions. The operation "Pipe Cleaner" mission ended in December 1964 at Lincoln AFB.
Effective 1 January 1965 all KC-135A and KC-135B used in the PACCS were re-designated as EC-135A and EC-135C, respectively. This re-designation properly identified the "Electronic" mission of the ABNCP's and to distinguish them from other KC-135 tankers.
PACCS underwent another major reorganization on 25 March 1965. The EB-47L mission "Pipe Cleaner" and their respective units at Lockbourne AFB and Mountain Home AFB were de-activated (EB-47L units at Lincoln AFB and Plattsburgh AFB had already been de-activated). Their radio-relay missions were absorbed by EC-135A's assigned to the 32nd AREFS, 301st AREFW at Lockbourne AFB, Ohio and the 28th AREFS, 28th BW at Ellsworth AFB, South Dakota, respectively.
On 1 November 1965 and shortly after being converted to the jet-powered EC-135A ABNCP, the 7120th ACCS moved to RAF Mildenhall, England.
In the mid 1960's, three EC-135J (modified from KC-135B aircraft) were based at Andrews AFB, MD and became Operation Nightwatch. These aircraft provided the US President and the NCA a safe way out of Washington in the event of a nuclear attack.
The PACCS was now exclusively EC-135A and EC-135C aircraft. The SAC ABNCP and AUXCPs missions became exclusively EC-135C aircraft while the radio-relay mission was exclusively the EC-135A aircraft.
The Western Auxiliary Command Post (WESTAUXCP) 15th AF March AFB, California "Step Mother", the Eastern Auxiliary Command Post (EASTAUXCP) 8th AF Westover AFB, Massachusetts "Achieve" and the Central Auxiliary Command Post (CENTAUXCP) 2nd AF Barksdale AFB, Louisiana "Greyson" were all EC-135C aircraft and finally the Radio Relay aircraft EC-135L at Grissom AFB, Indiana "Cover All". The CINC European Forces (CINCEUR) based at RAF Mildenhall, England "Silk Purse".
The value of the EC-135 ABNCP, as a survivable platform capable of directing retaliatory strikes against the Soviet Union, was powerfully demonstrated on 17 April 1967. An airborne battle staff successfully launched a Minuteman II ICBM from Vandenberg AFB after receiving "the necessary launch signal". Only SAC airborne launch platforms "Looking Glass" and AUXCP EC-135Cs and the newly modified Airborne Launch Control Center (ALCC) EC-135A's and EC-135G's, had an Airborne Launch Control System (ALCS) installed. The ALCS, which achieved its initial operational capability on 31 May 1967, was operated by a SAC missile crew flying aboard the airplane and incorporated the same safeguards against accidental launch as in ground control centers.
On 1 January 1970, the 10th ACCS at RAF Mildenhall, England acquired the resources and mission of the 7120th ACCS. The 10th ACCS provided a pilot, co-pilot, navigator, boom operator, and radio operator for the re-designated EC-135H CINCEUR ABNCP on alert for the United States CINCEUR. A battle staff, representing all four services, came from another organization to operate the ABNCP during exercises. Out of RAF Mildenhall the squadron flew varied flight plans to Southern England, Scotland or swap with another ABNCP from Lajes Field, Azores. They carried out air to air and air to ground communications tests. They also performed air to air refueling and training exercises. Flights were made to Rota AB, Spain for the aircraft to be washed down.
On 1 April 1970, SAC underwent a major reorganization that completely altered the PACCS structure but not its mission. The SAC ABNCP continued its 24-hour airborne alert and the AUXCPs, ALCCs, and Radio Relay aircraft remained on 15 minute ground alert. Air Refueling and Strategic Reconnaissance Squadrons that had operated PACCS aircraft were relieved of this responsibility.
The aircraft and crews were assigned to newly formed Airborne Command and Control Squadrons (ACCS). The 38th SRS, 55th SRW at Offutt AFB, Nebraska, the 305th AREFS, 305 AREFW at Grissom AFB, Indiana and the 28th AREFS, 28th BW at Ellsworth AFB, South Dakota transferred their EC-135s and crews to the 2nd ACCS, 55th SRW at Offutt AFB, the 3rd ACCS, 305th AREFW at Grissom AFB, Indiana and the 4th ACCS, 28th BW at Ellsworth AFB, South Dakota, respectively.
The 2nd ACCS was responsible for both the EC-135C SAC ABNCP "Looking Glass" and the the MIDAUXCP or CINCAC Support (24 hour ground alert). This provided a survivable battle staff suite for the CINCSAC, provided there was sufficient warning time for him to arrive at the aircraft prior to its alert launch.
The 3rd ACCS supported EC-135C EASTAUXCP and EC-135L Radio Relay platforms. In addition to its role as a back-up to "Looking Glass", the EASTAUXCP provided a secondary source of secure communications with the NCA to the east of Offutt AFB and "Looking Glass". Both the EASTAUXCP and Radio Relays sat 24 hour ground alert at Grissom AFB and at Lockbourne AFB (later renamed Rickenbacker ANGB).
The 4th ACCS operated the WESTAUXCP and the ALCCs. The WESTAUXCP, typically an EC-135C but occasionally an EC-135G with an approved mission degrade, provided a secure radio link between "Looking Glass" and the two or three airborne ALCCs, which orbited above the Minuteman "missile fields" in the Dakotas, Wyoming, Nebraska, Colorado, and Montana. One ALCC sat alert alongside the WESTAUXCP at Ellsworth, and the other two ALCCs sat alert at Minot AFB, North Dakota.
The PACCS reorganized again in 1974, seeing the stand-up of the 6th ACCS at Langley AFB, Virginia. Operation "Scope Light" provided EC-135P ABNCP support to the Commander in Chief, U.S. Atlantic Command (CINCLANT).
During the 1970's, plans were made to replace the Nightwatch EC-135J model aircraft with a modified Boeing 747, called the E-4A. The aircraft, initially called the Advanced Airborne Command Post (AABNCP), was soon deemed appropriate for the National Emergency Airborne Command Post (NEACP) or Nightwatch mission. In 1974 all 3 EC-135J ABNCP's were transferred to the 9th ACCS at Hickam AFB, Hawaii and Operation "Blue Eagle" was stood up and began providing the Commander in Chief, U.S. Pacific Command (USCINCPAC) a survivable ABNCP.
When the first E-4B (75-0125) entered the inventory, it was used to support both the NEACP and Looking Glass missions on a trial basis. This first E-4B Looking Glass mission occurred on 4 March 1980 and was deemed a provisional success. The E-4B was equipped with the Airborne Launch Control System (ALCS) and the first ICBM launch conducted from this platform occurred on 1 April 1981. The 2nd ACCS crew, flying aboard the E-4B, launched a Minuteman missile from Vandenberg AFB, CA as part of the Operational Test and Evaluation (OT&E) program. Although the Looking Glass capability remained for a while, the use of the E-4B was infrequent and the decision was made to revert it back to its primary role, which was providing a survivable ABNCP for the National Command Authority (NCA).
The 3rd ACCS was de-activated on 31 December 1975. Its Radio Relay operation was assumed by the 70th AREFS at Grissom AFB, Indiana and its EASTAUXCP operation duties by the 2nd ACCS at Offutt AFB, Nebraska.
For the next 15 years, SAC's ABNCP fleet remained constant in numbers, mission, and organization. Centered around a EC-135C "Looking Glass" operated by the 2nd ACCS, the PACCS fleet included two AUXCPs (one from the 2nd ACCS , the EASTAUXCP and one from the 4th ACCS the WESTAUXCP) on 15 minute ground alert. The 4th ACCS provided ALCCs No. 1, 2 and 3, and the 70th AREFS supported Radio Relays No. 1 and 2. The ALCCs and the WESTAUXCP were on satellite alert at Minot AFB, and Radio Relay No. 2 was on alert at Rickenbacker ANGB, Ohio (formerly Lockbourne AFB).
In the event of a national emergency, "Looking Glass" and the two AUXCPs would orbit above the Minuteman missile fields in the central US, the three ALCCs would orbit above the Minuteman missile fields in the north central and northwest US, and the two Radio Relay platforms would orbit over the Midwest, establishing and maintaining communications links with the Nightwatch ABNCP over the east coast.
In the summer of 1984, Lajes Field in the Azores undertook Operation Silk Purse as the EC-135H's began operating out of Lajes Field as an ABNCP for the USCINCEUR. Along with the aircraft came the USEURCOM battle staff and flight crews from United States Air Forces in Europe. This mission was ended in late August 1991.
EC-135 Looking Glass aircraft were airborne 24 hours a day for over 29 years until 24 July 1990, when "The Glass" ceased continuous airborne alert, but remained on ground or airborne alert 24 hours a day.
KC-135B tail number 62-3581, as an early Looking Glass aircraft later designated as an EC-135C.
Early 60's video documentary of Looking Glass