Aircraft Factfile and Recognition Guide –
RC-135 Family
The
COBRA BALL is an Air Force airborne intelligence platform (RC-135)
which carries infrared telescopes for tracking ballistic-missile tests
at long range. The COBRA BALL aircraft, operating out of Eielson AFB
AK, allow the United States to monitor every reentry vehicle flown from
Russian test ranges, to determine the capabilities of each Russian
missile, new or old.
The Cobra Ball suite of Signals Intelligence (SIGINT) and Measurements
and Signatures Intelligence (MASINT) sensor systems designed to exploit
the enemy electromagnetic spectrum. The MASINT sensors are two linked
electro-optical sensors -- the Real Time Optics System (RTOS) and the
Large Aperture Tracker System (LATS). RTOS consists of an array of
staring sensors encompassing a wide field of regard for target
acquisition. LATS serves as an adjunct tracker. Due to its large
aperture, it has significantly greater sensitivity and resolving power
than the RTOS, but is otherwise similar. Connectivity includes JTIDS
and TIBS data links.
Variants have been proposed for the operational detection of theater
ballistic missile launches. In war, Cobra Ball could provide rapid
recognition of TBM launches following cloud-break and horizon
clearance. Within seconds of launch detection, estimates of launch
point, intercept point, and impact point are available for transmission
over a data link to theater C4I elements like AWACS, JSTARS, and the
AOC. Estimates of increasing accuracy are transmitted during the course
of the missile's flight until burnout has occurred.
The Big Safari program delivered A/C 61-2664 (Cobra Ball II) in March
of 1972. On 15 March 1981, aircraft 664 tragically crashed upon
approach to Shemya AFS, Alaska, taking with it a combined SAC and ESC
crew of 24 -- resulting in six fatalities.
E-Systems converted the COBRA EYE RC-135X (62-4128) into another COBRA
BALL, which was slated for delivery during 1997, allowing the Air Force
to have two aircraft constantly available for deployment. Previously,
the Air Force operated two aircraft, but this resulted in a shortfall
every three years when one of the aircraft underwent programmed depot
maintenance at Raytheon/E-Systems in Greenville, TX. Two COBRA BALLs
will constitute the primary assigned aircraft inventory, with the third
in backup status receiving system upgrades. The backup status will
rotate among the three aircraft as each plane undergoes depot work.
RC-135U Combat Sent
COMBAT SENT is an RC-135
aircraft employed as a Scientific and Technical ELINT Collection
System. Two COMBAT SENT RC-135Us are assigned to the 55th Wing at
Offutt AFB, and are flown by crews from the 45th RS along with the
343rd RS and 97 IS, also at Offutt AFB. USAF Rome Laboratory is using
computers and expert systems as enabling technology to re-engineer and
improve COMBAT SENT Mission Management.
Rome Lab's Expert Mission
Manager is a "rule-based" automated tool which enables quick ELINT
collection responses to short up-time or otherwise hard-to-collect
signals. ELINT databases such as the National Signal Databases, EWO
information sheets ("Raven Notes"), ELINT collection Concept of
Operations and ELINT collection quality metrics, and heuristic rules
are all embedded within the Expert Mission Manager to enable real-time
operation.
The Expert Mission Manager
operates in real-time on collected ELINT signals to
- Validate and
re-identifies Electronic Intelligence (ELINT) signals
- List ELINT collection priorities
- Recommend action based on location
and priority
- Identify best geolocation of
aircraft for optimum ELINT collection
- Recommend what assets to tune
for the collection.
This capability provides the
ELINT Mission Coordinator with the tools to effectively direct the
ELINT collection effort aboard the COMBAT SENT aircraft -- making sure
that high priority, new or unknown signals are properly collected for
detailed analysis.
Rome Lab's Expert Mission
Manager program is sponsored by the Air Force's Consolidated
Cryptologic Program for ELINT Analysis Techniques. The objective of
this Consolidated Cryptologic Program effort is to apply advanced
processing techniques to the COMBAT SENT aircraft in order to improve
COMBAT SENT mission collections by automatically processing all the
knowns and usuals -- leaving the more difficult signals and unknowns to
the on-board personnel.
The COMBAT SENT Operator
Workstation Upgrade procures and installs high resolution operator
displays to improve target detection and signal recognition. Wide band
fiber optic base audio distribution network to all operators. Wide
band, high capacity COTS audio recorders. High capacity, digital,
reprogrammable, wideband demodulators and processors. Current display
resolution is insufficient to allow accurate signal detection and
recognition of modern modulation target signals. Several current target
emitters exceed the bandwidth of the current audio distribution system,
resulting in unintelligible audio output. Several receiver outputs are
routed to specific operator positions, limiting flexibility in
responding to theater driven dynamic target environments. Bandwidth and
capacity of current recorders is exceeded by an emerging class of
wideband modern modulation target emitters. Bandwidth and capacity of
current signal demodulators is exceeded by an emerging class of
wideband modern modulation target emitters. Current demodulators are
not reprogrammable. It is expensive and time consuming to reconfigure
them to process different target emitters.
Re-engining of RC-135 aircraft
with CFM-56 engines modifies the airframes to support re-engining. This
effort decreases cost of ownership and increases operational capability
by installing new, fuel efficient engines. Reduces maintenance manpower
and logistics costs; the new is more reliable than the current engine,
and the engine is common with the AMC KC-135 fleet. Extends unrefueled
range and time-on-station, and permits operations at higher altitudes,
increasing airborne sensor field of view and effectiveness. Increased
altitude range provides flexibility to airspace planners integrating
aircraft into congested airspace just behind the FEBA. Decreases
dependency on tankers for air refueling. Provides capability to takeoff
on shorter runways at increased gross weights. Facilitates two-level
maintenance concept reducing costs by 32%. Supports improved aircraft
environmental system prolonging sensitive sensor life.
COMBAT SENT Cockpit
Modernization includes the COMBAT SENT in the Air Force PACER CRAG
initiative to upgrade the C-135 fleet cockpit, and installs the
GATM/FANS avionics required to operate in the evolving civil air
structure. PACER CRAG installs new compasses, radar, multi-function
displays, and global positioning system/flight management system. New
fuel panel, Mode S IFF, TCAS, precision altimeters, and DAMA compliant,
8.333 KHz channel radios are included in this upgrade. Provides COMBAT
SENT aircraft commonality with the C-135 fleet for training, logistics,
and parts. Eliminated "vanishing vendor" problems associated with
diverging from the KC-135 avionics. Permits aircraft to comply with
ICAO navigation and communication standards to operate in the
trans-oceanic and European portions of the commercial air structure.
Improves safety, reliability, and maintainability of aircraft. PACER
CRAG kits/generic installation funds provided by AMC. Aircraft will be
denied access to increasing portions of civil air space without proper
navigation/communications equipment. Current avionics systems will
become unsupportable as KC-135 migrates to newer equipment. Commonality
will be lost with the rest of the C-135 fleet. Common parts supply base
will not be available.
COMBAT SENT Calibration
Systems replaces obsolete and unsupportable components of the Emitter
Source Van (ESV) and the Portable Calibration Van (PCV) used to
generate test signals to calibrate aircraft antenna and RF distribution
system. Provides modern modulation capability and millimeter wave
frequency calibration. Returns aircraft system calibration accuracy to
required level. It replaces failing components of the ESV and PCV.
Modernizes computer assets which have become obsolete and
unsupportable. Provides modern modulation capability to enable test and
calibration of systems designed to exploit frequency agile, coded
pulse, and coherent radar weapon systems. Provides high frequency
millimeter wave calibration signals. COTS computer systems used in both
ESV and PCV will become unsupportable in the FY05-06 years. Sensors
designed to exploit modern weapon systems must be calibrated against
similar signals to ensure accurate measurements. Increasing use of
millimeter wave frequencies in direct threat systems makes calibration
critical for weapon system characterization.
COMBAT SENT Wideband
Acquisition/Frequency Hopping Receiver System (FHRS) provides wideband
acquisition and frequency hopping receiver system (FHRS) capability for
exploitation of frequency agile threat systems. Builds on previous
efforts to provide unique capability for precision measurement and
exploitation of modern, frequency agile radar. Uses shared antennas and
pooled computer assets with high speed, JASA compliant network to
integrate existing reconnaissance systems with wideband receiver and
de-hopping systems. Allows real-time acquisition and exploitation of
frequency-agile threats. Enhances probability of intercept for LPI
systems and increases tip-off capability. Will enhance the unique
capability to intercept and exploit radar transmission characteristics
to include modern frequency-agile threats. Enables collection of data
essential for electronic warfare system reprogramming and design.
Modern threats are increasingly using frequency agility to counter
fielded systems. These threat systems cannot be adequately
characterized by existing collection systems. This increases the margin
of error required to be used in mission and route planning, as well as
increasing the cost of LO, HARM, and electronic warfare system design
because of the inability to accurately characterize the threat system.
COMBAT SENT RF Distribution
System Improvement procures and installs antennas and RF distribution
system capable of intercepting frequency agile radars. Redesigns wing
RF distribution system to permit installation of new RC-135 engines.
Enhances power, beam pattern, and polarization (P3) collection on
narrowband signals. Expands collection system field of view, increases
sensitivity and implements standard data links for increased
cross-platform cueing, near-real-time reporting, and tactical support
capabilities. Installs industry standard ID-1 wideband recorders.
Implements common aperture RF distribution/fiber optics (CARF) to allow
re-engining and collection of frequency hopping radars. Enhances P3
collection by adding improved near-real-time processing and reporting
along with narrowband collection capability. Allows near-real-time
reporting and cross-platform cueing through common data links
(TADIL-J/TIBS). Increases training and collection capacity through
improved carry-on terminals. Increases ability to exploit wideband
threats through higher bandwidth recorders. Cannot reinstall P3
collection system after re-engine without common aperture RF
distribution/fiber optics (CARF). CARF allows 360° field-of-view
and exploitation of frequency hopping radars. Improved processing and
communication provides enhanced cross-platform tip-off, and P3
information in near-real-time for mission planning and threat
avoidance. Operator workload is reduced by enhanced P3 system
automation, data management, and reduced complexity allowing operation
in more complex, more diverse threat environments.
RC-135V/W Rivet Joint
The USAF RC-135V/W RIVET
JOINT surveillance aircraft are equipped
with an extensive array of sophisticated intelligence gathering
equipment enabling military specialists to monitor the electronic
activity of
adversaries. Also known as "RJ", the aircraft are sometimes called
"hogs" due to the extended "hog nose" and "hog cheeks". RIVET JOINT has
been widely used in the 1990's -- during Desert Storm, the occupation
of Haiti, and most recently over Bosnia. Using automated and manual
equipment, electronic and intelligence specialists can precisely
locate, record and analyze much of what is being done in the
electromagnetic spectrum. The fleet of 14 RIVET JOINT aircraft
increased to 15 in late 1999 with the addition of a converted C-135B.
The jet's conversion cost about $90 million.
Basic roles include:
- Providing indications about the location and intentions of
enemy forces and warnings of threatening activity.
- Broadcasting a variety of direct voice communications. Of
highest priority are combat advisory broadcasts and imminent threat
warnings that can be sent direct to aircraft in danger.
- Operating both data and voice links to provide target info
to US ground based air defenses.
The RIVET JOINT aircraft
are capable of conducting ELINT and COMINT
intercept operations against targets at ranges of up to 240 kilometers
[in contrast to the 280 kilometer intercept range of the higher-flying
U-2].
The RIVET JOINT aircraft operated by the 55th Wing, Offutt Air
Force Base, Neb., provide direct, near real-time reconnaissance
information and electronic warfare support to theater commanders and
combat forces. In support of the 55th, the 95th Reconnaissance Squadron
operates out of Mildenhall and provides pilots and navigators to fly
the aircraft. The 488th Intelligence Squadron provides the intelligence
personnel who work in the back of the plane. Since the beginning of
Operation Joint Endeavor
December 21, 1995 through May 1996 the 95th and 488th flew 625 hours
and 72 sorties together in support of the peacekeeping operation in
Bosnia-Herzegovina.
RIVET JOINT (RC-135V/W) is an air refuelable theater asset
with
a nationally tasked priority. It collects, analyzes, reports, and
exploits enemy BM/C4I. During most contingencies, it deploys to the
theater of operations with the airborne elements of TACS (AWACS, ABCCC,
Joint STARS, etc.) and is connected to the aircraft via data links and
voice as required. The aircraft has secure UHF, VHF, HF, and SATCOM
communications. Refined intelligence data can be transferred from Rivet
Joint to AWACS through the Tactical Digital Information Link TADIL/A or
into intelligence channels via satellite and the TACTICAL INFORMATION
BROADCAST SERVICE (TIBS), which is a nearly real-time theater
information broadcast.
Recognizing
the RC-135 Series
The RC-135 family resembles the
older Boeing 707s with several exceptions, which will be listed below
the main description. Here's
tips on how to identify one:
Wings: Low-mounted, swept-back, and
tapered with a positive slant. An electronics pod is mounted on the
each wing-tip.
Engines: Four large, round turbofans mounted on pylons
under the wings. Engines extend forward of the wings’ leading edges.
Fuselage: Round, cigar-shaped, tapers to the rear. Rounded
nose, stepped-up cockpit.
Tail: Swept-back, tapered fin with a square tip. Flats are
swept-back, tapered, and mid-mounted on the fuselage.
RC-135S Cobra Ball: In
addition to "thimble" noses, electronic receivers
mounted in cheek fairings and a teardrop-shaped fairing on the
aft fuselage, these also have large circular windows in the
fuselage for the photography of foreign ballistic-missile tests
at long range.
RC-135U Combat Sent: Cheek
fairings and additional fairings in the chin, boomer, wingtip,
tail cone and fin-top positions.
RC-135V/W Rivet Joint:
Extended "thimble" noses and large plate aerials under
the center-section. External differences between the two variants
are restricted to a lengthened cheek fairing on the W-model,
which also lacks auxiliary air intakes on its engine pods.
Specifications
RC-135U Combat Sent
Primary
function: Electronic intelligence reconnaissance and surveillance
Contractor:
Boeing Aerospace
Power
Plant: Four Pratt & Whitney TF33-P-9 turbofans
Thrust:
16,050 pounds per engine
Length:
140 feet, 1 inch (42.6 meters)
Height:
41 feet, 8 inches (12.7 meters)
Wingspan:
135 feet, 1 inch (41.4 meters)
Speed:
350 Knots Indicated Air Speed
Ceiling:
35,000+ feet (10,668+ meters).
Maximum
Takeoff Weight: 299,000 pounds (135,626.4 kilograms)
Range:
4,000 nautical air miles (Unlimited with air refueling)
Crew:
Two pilots, two navigators, two airborne systems engineers, and a
minimum
of 10 electronic warfare officers (flight crew from
45th RS) and six or more mission area specialists (mission crew from
97th IS)
Date
Deployed: Not available
RC-135V/W Rivet Joint
Primary
Function: Reconnaissance
Contractor:
L-3 Communications
Power
Plant: Four CFM International F108-CF-201 high bypass turbofan
engines
Thrust:
21,600 pounds each engine
Unrefueled
Range: 3,900 miles (6,500 kilometers)
Length:
135 feet (41.1 meters)
Height:
42 feet (12.8 meters)
Maximum
Takeoff Weight: 297,000 pounds (133,633 kilograms)
Wingspan:
131 feet (39.9 meters)
Speed:
500+ miles per hour (Mach.66)
Flight
Crew: Five (augmented) - three pilots, two navigators
Mission
flight crew: 21-27, depending on mission requirements, minimum
consisting
of three electronic warfare officers, 14
intelligence operators and four in-flight/airborne maintenance
technicians
Date
Deployed: Initial RC-135 conversions from 1964-1968; V/W
configurations, 1981
Sources: Federation
of American Sciences, GlobalSecurity.org
Combat Sent, USAF
RC-135U Factfile, USAF
RC-135V/W Factfile
© 2004-2007 Steven
Holzinger