KC-135A Reconnaissance Platforms At least four KC-135A tankers were converted into makeshift reconnaissance platforms with no change of Mission Design Series (MDS) designation. KC-135As 55–3121, 55–3127, 59–1465, and 59-1514 were modified beginning in 1961. That year the Soviet Union announced its intention to detonate a 100 megaton
thermonuclear device on
Novaya Zemlya, the so-called
Tsar Bomba. A testbed KC-135A (55–3127) was modified under the
Big Safari program to the SPEED LIGHT BRAVO configuration in order to obtain intelligence information on the test. The success of the mission prompted conversion of additional aircraft for intelligence gathering duties.
KC-135R Rivet Stand / Rivet Quick Not to be confused with the CFM F108-powered KC-135R tanker, the KC-135R MDS was applied in 1963 to the three KC-135A reconnaissance aircraft under the
Rivet Stand program. The three aircraft were 55–3121, 59–1465, and 59–1514. A fourth, serial no. 58–0126, was converted in 1969 to replace 1465, which crashed in 1967. Externally the aircraft had varied configurations throughout their careers, but generally they were distinguished by five "towel bar" antennas along the spine of the upper fuselage and a radome below the forward fuselage. The first three aircraft retained the standard tanker nose radome, while 58-0126 was fitted with the 'hog nose' radome commonly associated with an RC-135. A trapeze-like structure in place of the refueling boom which was used to trail an aerodynamic shape housing a specialized receiver array, colloquially known as a "blivet", on a wire was installed. This was reported to be used for "Briar Patch" and "Combat Lion" missions. There were four small optically flat windows on each side of the forward fuselage. On some missions, a small wing-like structure housing sensors was fitted to each side of the forward fuselage, with a diagonal brace below it. With the loss of 59–1465, KC-135A 58-0126 was modified to this standard under the
Rivet Quick operational name. All four aircraft were lost in accidents or converted to KC-135R tanker configurations. They are among the few KC-135 tankers equipped with an aerial refueling receptacle above the cockpit, a remnant of their service as intelligence gathering platforms.
KC-135T Cobra Jaw In 1969, KC-135R 55-3121 was modified by Lockheed Air Services to the unique KC-135T configuration, under the Cobra Jaw program name. Externally distinguished by the 'hog nose' radome, the aircraft featured spinning "fang" receiver antennas below the nose radome, a large blade antenna above the forward fuselage, a single 'towel bar' antenna on the spine, teardrop antennas forward of the horizontal stabilizers on each side, and the trapeze-like structure in place of the refueling boom. The aircraft briefly carried nose art consisting of the Ford Cobra Jet cartoon cobra. It was later modified into an RC-135T Rivet Dandy.
RC-135A Four RC-135As (63-8058 to 8061) were photo mapping platforms used briefly by the Air Photographic & Charting Service, based at
Turner Air Force Base,
Georgia and later at
Forbes Air Force Base,
Kansas as part of the 1370th Photographic Mapping Wing. The mission was soon assumed by satellites, and the RC-135As were de-modified and used in various other roles, such as staff transport and crew training. The primary Rivet Brass mission flew along the northern border of the Soviet Union, often as a shuttle mission between Eielson and
RAF Upper Heyford, Oxfordshire, and later
RAF Mildenhall, Suffolk, UK. The RC-135D was also used in Southeast Asia during periods when the RC-135M (see below) was unavailable. In the late 1970s, with the expansion of the RC-135 fleet powered by TF33 turbofan engines, the RC-135Ds were converted into tankers, and remain in service as receiver-capable
KC-135Rs. Originally delivered as a C-135B, 62-4137 operated from
Shemya Air Force Station,
Alaska from 1966 to 1969. Its operations were performed in concert with the RC-135S Rivet Ball aircraft (see below). The radar system alone weighed over 35,000 pounds and cost over US$35 million (1960 dollars), making Rivet Amber both the heaviest C-135 derivative aircraft flying and the most expensive Air Force aircraft for its time. This prevented the forward and aft crew areas from having direct contact after boarding the aircraft. On the opposite wing, in the same location, was a podded heat exchanger to permit cooling of the massive electronic components on board the aircraft. This configuration has led to the mistaken impression that the aircraft had six engines. On 5 June 1969, Rivet Amber was lost at sea on a
ferry flight from Shemya to Eielson AFB for maintenance. No trace of the aircraft or its crew was ever found.
RC-135M Rivet Card The RC-135M was an interim type, with more limited ELINT capability than the RC-135C, but with extensive additional COMINT capability. They were converted from
Military Airlift Command C-135B transports, and operated by the
82d Reconnaissance Squadron during the
Vietnam War from
Kadena Air Base, gathering
signals intelligence over the
Gulf of Tonkin and Laos with the program name Combat Apple, originally Burning Candy. There were six RC-135M aircraft, 62–4131, 62–4132, 62–4134, 62–4135, 62–4138 and 62–4139. All were later modified to and continue in active service as RC-135W Rivet Joints by the early 1980s.
RC-135S Nancy Rae / Wanda Belle / Rivet Ball Rivet Ball was the predecessor program to Cobra Ball and was initiated with a single RC-135S (serial 59–1491, formerly a JKC-135A) on 31 December 1961. The aircraft first operated under the Nancy Rae project as an asset of
Air Force Systems Command, and later as an RC-135S reconnaissance platform with Strategic Air Command under project Wanda Belle. The name Rivet Ball was assigned in January 1967. The aircraft operated from Shemya AFB, Alaska. Along with most other RC-135 variants, the RC-135S had an elongated nose radome, housing an
S band receiving antenna. The aircraft had ten large optically flat quartz windows for tracking cameras on the right side of the fuselage. Unlike any other RC-135S, Rivet Ball had a plexiglass dome mounted top-center on its fuselage for the Manual Tracker position. It obtained the first photographic documentation of Soviet
Multiple Reentry vehicle (MRV) testing on 4 October 1968. On 13 January 1969, Rivet Ball was destroyed when it overran the runway when landing at Shemya, with no fatalities. The Cobra Ball monitors missile-associated signals and tracks missiles during boost and re-entry phases to provide reconnaissance for treaty verification and
theater ballistic missile proliferation. The aircraft are extensively modified C-135Bs. There are three aircraft in service, assigned to the
55th Wing,
45th Reconnaissance Squadron based at
Offutt Air Force Base, Nebraska. Cobra Ball aircraft were originally assigned to Shemya and used to observe ballistic missile tests on the
Kamchatka peninsula in conjunction with
Cobra Dane and
Cobra Judy. In 1969, two aircraft were converted for Cobra Ball. Following the loss of an aircraft in 1981, another aircraft was converted in 1983. In 1995, the sole RC-135X was converted into an RC-135S to supplement the other aircraft.
RC-135T Rivet Dandy In 1971, KC-135T 55-3121 was modified to a RC-135T Rivet Dandy configuration. It was used to supplement the RC-135C/D/M fleet, then in short supply due to ongoing upgrades requiring airframes to be out of service. It operated under the Burning Candy operational order. In 1973, the aircraft's SIGINT gear was removed and transferred to KC-135R 58–0126, resulting in 55-3121 assuming the role of trainer, a role which it fulfilled for the remainder of its operational existence. Externally the aircraft retained the 'hog nose' radome and some other external modifications. The aerial refueling boom and trapeze below the tail were removed, and it had no operational reconnaissance role.
RC-135U Combat Sent The RC-135U Combat Sent is designed to collect technical intelligence on adversary radar emitter systems. Combat Sent data is collected to develop new or upgraded
radar warning receivers,
radar jammers, decoys,
anti-radiation missiles, and training simulators.
RC-135V/W Rivet Joint The RC-135V/W is the USAF's standard airborne
SIGINT platform. Missions flown by the RC-135s are designated either
Burning Wind or
Misty Wind. Its sensor suite allows the mission crew to detect, identify and
geolocate signals throughout the
electromagnetic spectrum. They have flown from
Eielson AFB,
Alaska;
Howard AB,
Panama;
Hellenikon Air Base,
Greece;
Kadena Air Base,
Okinawa,
Japan; and
RAF Mildenhall, Suffolk, and
RAF Upper Heyford, Oxfordshire, in the
United Kingdom. For many years, the RC-135V/W could be identified by the four large disc-capped Multiple Communications Emitter Location System (MUCELS) antennas forward, four somewhat smaller blade antennae aft and myriad of smaller underside antennas. Baseline 8 Rivet Joints, in the 2000s, introduced the first major change to the external RC-135V/W configuration, replacing the MUCELS antennas with plain blade antennas. The configuration of smaller underside antennas was also changed significantly.
RC-135W Rivet Joint (Project Airseeker) The United Kingdom bought three KC-135R aircraft for conversion to RC-135W Rivet Joint standard Acquisition of the three aircraft was budgeted at £634m, with entry into service in October 2014. The aircraft formed
No. 51 Squadron RAF, based at
RAF Waddington along with the RAF's other ISTAR assets. They are expected to remain in service until 2045. Previously, the Royal Air Force had gathered signals intelligence with three
Nimrod R1 aircraft. In 2008, the option of switching to Rivet Joint was added to Helix, As of September 2010 the aircraft had approximately 23,200 flying hours, 22,200 hours and 23,200 hours. In January 2011, 51 Sqn personnel began training at Offutt for conversion to the RC-135. The first RC-135W (ZZ664) was delivered ahead of schedule to the Royal Air Force on 12 November 2013, for final approval and testing by the Defence Equipment and Support team prior to its release to service from the
UK MAA. The second (ZZ665) was delivered in September 2015 and the third (ZZ666) in June 2017. The latter entered operational service in December 2017.
RC-135X Cobra Eye The sole
RC-135X Cobra Eye was converted during the mid-to-late-1980s from a C-135B Telemetry/Range Instrumented Aircraft, serial number 62–4128, with the mission of tracking ICBM
reentry vehicles. In 1993, it was converted into an additional RC-135S Cobra Ball.
TC-135 Three aircraft are in service for crew training, and lack fully functional mission equipment. One TC-135S (62–4133) provides training capability for the Cobra Ball mission, and is distinguishable from combat-ready aircraft by the lack of cheeks on the forward fuselage. It was converted from an EC-135B in 1985 following the crash of the former RC-135T 55–3121, which had been used as a trainer up to that point. Two TC-135Ws (62-4127 and 4129) serve as training aircraft, primarily for the Rivet Joint mission, but can provide some training capability for RC-135U Combat Sent crews. They carry considerably fewer antennas than the fully equipped aircraft, but are otherwise similar in appearance to other Rivet Joint aircraft. ==Operators==