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Editor's Note July 2007:
this technical profile of the Tu-95/142 was compiled from the best then
available materials. Since the collapse of the Soviet Union in 1991,
significantly more detail was become available on the early history of
the Bear and the detailed configuration of the wide range of variants
employed. A more recent Bear analysis is now available [More...].
Of all of the descendants of
the Boeing B-29, the Tupolev Bear is the most remarkable. The Bear is a
mainstay of Russia's strategic aviation forces and a key element in
Russian naval strategy, being currently in production to support at
least one of these roles. The new Bear H is Russia's first cruise
missile carrier and as such has led the United States to deploy an
immense network of Over-The Horizon (OTH) radars, quite a feat for a
design of the Bear's age.
The origin of the Bear may be traced back to 1945, when
several USAAF B-29 aircraft, severely damaged by Japanese defences,
landed in Russian territory. While the crews were repatriated, the
B-29s never left Siberia. Engineers from the Tupolev and Shvetsov
bureaus, despatched from their plants, proceeded to strip the aircraft
down to the last component, analysing and documenting all.
In 1945, Russian bomber design was at its worst for decades,
the only production four engined bomber being of prewar design and
hopelessly inadequate in comparison with the USAF's B-29 fleet. Russia
needed a capable bomber to project its newly acqui red nuclear
capability and copying the B-29 was the least painful way of getting
one. It is to the credit of the robust B-29 that it could be
successfully produced in an industrial infrastructure as obsolete as
that of the USSR in 1949.
Hailed as a fully Soviet design, the Tu-4 Bull first flew in
1947 and entered series production in 1949, 1200 were eventually built.
The Russians copied the airframe, powerplants, systems and the unique
fire control system which remotely controlled the four gun turrets. The
notable difference between the aircraft was in the Russian installation
of NS-23 cannon in preference to the 50 calibre guns of the B-29.
While the Tu-4 provided Russia with a credible nuclear strike
force, the US deployment of the B-50, B-36 and B-47 made it quite
apparent that a more capable aircraft was required. The Tupolev bureau
developed the Tu-4 design into the larger Tu-80 and Tu-85, eventually
adopting the characteristic glazed nose and stepped forward fuselage
used to this date.
Neither of these aircraft was considered successful and the
Russians turned to their newly developed turbojets and turboprops, thus
spawning two major families of aircraft - the Badger and the Bear.
The Tupolev Tu-95
The Badger and the Bear were both evolutionary and
revolutionary in Russian aircraft design. The evolutionary aspect was
in the design of the fuselage and systems, which directly illustrated
their Boeing heritage. The revolutionary aspect was in the application
of a swept wing and turbine powerplants.
The Tu-95 was designed in 1951/52 and first flew in 1955. The
fuselage of the Tu-95 resembles that of the B-29 in many respects, it
is circular in cross-section, with a pressurised shell fore of the
wings, has substantial structure to support the thick wing roots below
and behind which is situated a weapon bay. The fuselage behind the wing
retains the general configuration of its ancestor, although it appears
that only a single pressurised shell is used in most versions, below
the vertical stabiliser; this contains the aft gunner/operators'
stations. The tailplane is raised somewhat above the fuselage and a
tail gunner's station is situated at the end of the fuselage. Unlike
the B-29 with gunners stationed just aft of the wing, the Tu-95
gunner(s) have two large observation blisters below the tailplane. The
Tu-95 did however retain part of the remotely controlled gun turret
system of the Tu-4, with a retractable dorsal and a ventral barbette
each containing a pair of 23mm NR-23 cannon.
The glazed nose of the aircraft housed the
navigator/bombardier's station and is followed by a conventional flight
deck with dual controls. The forward fuselage almost certainly houses
additional stations for systems operators (eg. attack radar in later
derivatives), a gunner and possibly a mission commander or political
officer (this would not be a unique strategy, Japanese bombers such as
the Betty carried a commanders' seat just aft and slightly above the
pilots' stations and in view of the high degree of KGB control over
nuclear systems during the 1950s and 1960s would almost seem the
natural solution). The fuselage weapon bay is situated below and aft of
the wing roots, it could fit several high yield nuclear devices. It is
not clear whether the fuselage tunnel connecting the forward and rear
pressurised areas as used in the Tu-4 was retained, although it would
have made some sense given the expected duration of sorties.
Access to the rear pressurised area is almost certainly via a
ventral hatch (cf Badger), visible on some photographs.
The Tu-95's wing and powerplant were a radical departure from
its predecessors. The large swept wing with four pairs of fences
carried four large engine nacelles inboard and outboard Fowler flaps
and conventional ailerons. Its thickness and area provided considerable
volume for fuel, the noticeable anhedral on the ground disappears under
flight loading. The inboard nacelles end in large trailing edge pods
which conceal the main undercarriage. This arrangement offers a wide
track for stability, frees fuselage/centre section area for payload and
doesn't penalise the wing structure with the need for undercarriage
wells.
These attributes were so important to the Tupolev bureau that
this configuration became its trademark.
The powerplants, four huge 12,000 shp Kuznyetzov NK-12
turboprops driving counter-rotating four bladed AV-60 propellers,
typify Russian design philosophy - simplicity, size and attain ment of
performance through brute force. At the Tu-95's dash speed of 0.87 Mach
these props are supersonic well before the tips and certainly are not
operating at peak efficiency. Nevertheless this configuration offered
superior payload/range to the turbojets of the day without an
unreasonable penalty in cruise speed and this view no doubt prevails to
this day. In 1955 the speed and strike radius were adequate to defeat
many Western all weather air defence fighters.
One of the interesting side effects of the Tu-95's powerplant
arrangement is an incredible prop noise level, even at cruise speed the
blade tips are mildly supersonic in spite of the low speed on the 750
rpm props. One can have no doubt that prop harmonics must exact a solid
penalty in vibration induced failures of onboard electronic systems.
Image
Photographed off the Cocos islands by an RAAF P-3C is a
long-range maritime patrol and ASW aircraft. The AV-MF is believed to
operate about four dozen of these aircraft.
Another side effect of considerable importance today is the
tremendous radar cross-section of the whirling props, particularly from
the frontal aspect. Not only increasing the detection range of the
aircraft, the props also modulate the return and thus can betray the
aircraft's identity to an appropriately built radar system.
The Tu-95, often designated Tu-20, entered service with the
Dal'naya Aviatsia (DA - Long Range Aviation) of the Soviet VVS (Air
Force) in 1955, making its public debut in the 1955 Aviation Day
flypast. While many Western analysts didn't consider the Tu-95 a
serious competitor to the turbojet powered Myasishchev M-4, unveiled a
year earlier, Soviet air strategists clearly preferred the Tupolev for
its superior range and more adaptable configuration. The Myasishchev
M-4 Bison today serves primarily as a tanker.
While early derivatives of the Tu-95 designated by NATO as
Bear served as strategic nuclear strike aircraft, the airframe was
further developed as a passenger transport. The fuselage of the new
Tu-114 Cleat had a larger diameter than that of the Bear and employed a
low wing rather than mid wing configuration.
It achieved little success as an airliner but did provide an
airframe design for the Tu-126 Moss Airborne Early Warning system. The
Moss attained IOC in 1970, with a single aircraft deployed to India in
1971 in support of Indian air operations against Pakistan in the war
over Bangladesh. The Flat Jack AEW radar of the Moss has been credited
with very poor overland lookdown performance and this limitation in
capability may well be the reason for the Russians having only ever
deployed about a dozen of this type. It is now being replaced with the
new Il-76 Mainstay system.
Ultimately, the deployment of the missile armed century
series
fighters and the new Surface-to-Air-Missile (SAM) systems led to the
demise of the Bear as a strategic penetrator. It also marked the
beginning of an evolutionary path perhaps unique in aviation history, a
front line strategic combat aircraft maintained in production for over
three decades. No less than nine distinct versions of this aircraft
exist with many further subtypes of which at least one may still be in
series production.
Bear A
The Bear A was the initial nuclear strike version of the
Tu-95, with a glazed nose, chin mounted nav/attack radar and internally
carried free fall nuclear bombs. Given the state of Soviet electronic
warfare capability in the mid fifties, this aircraft relied heavily on
its six NR-23 cannon if threatened by interceptors in the aft
hemisphere. Given the fundamental limitations of this weapon system it
was soon supplanted by the Bear B.
Bear B
The Bear B was a dedicated long-range missile carrier, armed
with the massive AS-3 Kangaroo strategic nuclear standoff missile. The
Kangaroo was a substantial weapon and was derived from the Su-7 Fitter
airframe. As such it weighed about 25,000 lb at launch, of which 5,000
lb was a large thermonuclear device.
The Kangaroo was probably powered by an Al-7F afterburning
turbojet like the Fitter, with which it shares wing and fuselage
structure. The Bear B carried its Kangaroo recessed in a ventral bay. A
fairing covered the Kangaroo's inlet and almost certainly covered the
high pressure air starter system which would have been used for the
turbojet. Bear B located its targets with a large Crown Drum I-band
nav/attack radar which occupied most of the spacious nose. After
launching the Kangaroo the Bear provided guidance for the missile.
Some sources suggest the initial use of beam riding guidance
followed by datalink midcourse updates, although given the mission
profile it is very likely that the Kangaroo carried a simple beacon
transponder and was steered onto its target by an operator, a simple
autopilot maintaining heading and attitude. An A-336Z or 346Z datalink
was attributed to the Kangaroo midcourse guidance system. The Kangaroo
would be launched at about 40,000 ft from where it would climb to about
60,000 ft at 1.6 Mach and then enter a shallow 1.8 Mach dive onto its
target, which it would obliterate with its large thermonuclear warhead.
Maximum range was estimated as of the order of 350 nm.
The Bear B carried a tail warning and gunlaying radar below
the rudder, this may have been a Bee Hind although the Box Tail is
usually attributed to later versions of the type. The six NR-23 guns
were also retained. At a later stage these aircraft acquired the Sirena
II and III Radar Homing and Warning (RHAW) equipments and the standard
SRO-2 Identification Friend Foe (IFF) systems. Navaids included the
A322Z Doppler system and the RSBN-2 short-range navigation system.
The Bear B entered service in the early sixties, the DA
eventu
ally acquiring about 50 aircraft. Some have apparently been used in the
Maritime Reconnaissance role, with inflight refuelling probes fitted
and a large fairing on the aft starboard fuselage.
A Bear D photographed by RAF Phantoms over the North Sea
in 1973. The D version was primarily used as an intermediate launch
station monitoring aircraft which provided accurate guidance data for
anti-ship cruise missiles.
Bear C
The Bear C was first seen in 1964 shadowing Allied shipping.
This aircraft was a Kangaroo capable strike version with additional
blister fairings on the aft fuselage, almost certainly housing
Electronic Support Measures (ESM) antennas.
Some Bear C aircraft had their tail turrets deleted and
replaced with a streamlined tailcone fairing, also housing electronic
hardware.
Bear C retained the Crown Drum attack radar and was often
designated together with the Bear B as the Bear B/C in view of their
similarity.
Bear D
First sighted in 1967, the Bear D is a major version and one
of the most important types in the Russian Aviatsia Voenno Morskovo
Flota (AVMF-Soviet Fleet Air Arm) MR force. While it retains the glazed
nose of the Bear A it also carries the small chin radome of the I-band
Puff Ball nav/attack radar, an inflight refuel ling probe and its
distinguishing feature, the huge ventral radome associated with the
powerful I/J-band Big Bulge surface search and targeting radar. The
Bear D retains the fuselage antenna blisters of the MR/Strike Bear C
but has additional ESM fairings on the tips of its tailplane.
The defensive suite includes the Box Tail fire control radar
with the ventral barbette and tail turret retained as in earlier
aircraft. In some later aircraft the tail gunner's station is replaced
with a tailcone similar to that on some Bear C aircraft.
Bear D carries no offensive weapons but serves as an Over
The-Horizon (OTH) targeting platform for ship/sub launched
Surface-Surface Missiles (SSM), certainly relaying target positions and
very likely also providing midcourse guidance for SSMs such as the
200nm class SS-N-3A/B Shaddock and possibly the newer sub launched
300nm class SS-N-12.
The AV-MF employ 45 of this aircraft which has been reported
as being based at the Cam Ranh Bay airbase in Vietnam.
Bear E
The Bear E is a long-range recce version of which few were
apparently built. Its airframe is that of a Bear A with an inflight
refuelling probe, rear fuselage blisters and a sensor pallet in the
bomb bay.
Tu-142 Bear F
The Tu-142 is another AV-MF version. It entered service
around
1970 and is tasked with long-range Anti Submarine War fare (ASW) patrol
and Maritime Reconnaissance (MR). Bear F is also a major version and
its production was resumed as late as in the 1980s, while the basic
type has been through various system upgrades.
The fuselage of the late model (mod 2, 3, 4) Tu-142M Bear F
is
mission oriented with an A style but lengthened forward fuselage with a
glazed nose and chin radome as on some Bear Ds, inflight refuelling
probe, increased windscreen depth and bulged nose wheel doors. The
ventral radome of the surface search radar (possibly a derivative of
the Big Bulge) was shifted forward to allow stores carriage in the main
weapon bay, these include torpedoes and depth charges of various types.
The ventral and dorsal barbettes were removed from the aircraft to
provide space for a sonobuoy dispenser bay. Many Bear F aircraft also
carry a Magnetic Anomaly Detector (MAD) boom at the top of the vertical
stabiliser. Many earlier aircraft also had enlarged inboard engine
nacelles but this was later abandoned.
The Tu-142 like all later versions of the Bear is fitted with
the 14,795 shp NK-12MV turboprop which offers a dash speed of about
500kt at 40,000 ft and an unrefuelled combat radius of 4,475nm.
Approximately 55 of this version are in AV-MF service and the type is
apparently stationed at Cam Ranh Bay.
Bear G
The Bear G is the designation of a recent retrofit to older
Bear B/C aircraft. Like its predecessors the Bear G is a long-range
missile carrier, it is armed with a pair of very potent AS-4 Kitchen
missiles. The Bear G carries an inflight refuelling probe and retains
the distinctive radome of the Crown Drum attack radar, housing a new
Down Beat nav/attack radar common to the Backfire/AS-4. This suggests
the use of the Backfire's fire control and nav/attack systems.
An additional small radome is situated just beneath the
refuelling probe, its purpose is unclear although it could belong to
weather/nav radar or a high power ECM antenna (cf B-52G). Bear G is
fitted with a tailcone fairing similar to some Bear Ds but retains the
ventral barbette and its associated observation blisters. The rear
fuselage ESM blisters are further supplemented with additional radomes
above and below the new tail section, these are very probably
associated with ECM systems.
One analyst is quoted as having associated the tailcone with
a
large trailing VLF antenna (cf Tacamo) but this seems inconsistent with
the aircraft's strike role.
Image
The Tu-126 Moss is essentially a Tu-114 Cleat airframe,
developed in turn from the Bear and fitted with an airborne early
warning radar system. The Moss proved a failure in service and only
about a dozen were ever built, its role nowadays being taken over by
the more capable Mainstay derivative of the 11-76 Candid.
Table
This table was compiled from various sources and items such
as weights, performance and equipment fit should be treated with
caution. Many sources attribute the Bee Hind fire control radar to Bear
Bee Hind was carried by early versions but was superceded by the larger
Box Tail equipment. Late model Bear F and Bear H may carry newer
generation systems although at this stage nothing has been published in
the open literature (Author).
Bear G is tasked with long-range strike and can carry both
anti-shipping and nuclear versions of the AS-4 Kitchen on its two wing
root and one fuselage stations. The 14,3301b liquid propellant rocket
powered Kitchen was first deployed in the sixties and was carried on
Blinder and Backfire aircraft much like the RAF's somewhat smaller
Hawker Siddeley Blue Steel on Vulcans and Victors.
It carries a 2,000 lb warhead which may be conventional or
nuclear. Kitchen is usually launched at about 35,000 ft from where it
will climb to about 80,000 ft and cruise at 2.5 to 3.0 Mach before
entering a shallow dive to its target which may be up to 250nm from the
launch platform (some sources suggest up to 400nm). Alternately
Kitchen may be launched directly into a shallow dive at a target up to
170nm away. Kitchen employs inertial or autopilot midcourse guidance
and a J-band active radar seeker is used for terminal homing in the
anti-shipping versions. IOC for the Bear G was estimated as 1984 and
while this aircraft has the ability to hit land targets, its primary
role lies in interdicting Western shipping lanes for which it is best
equipped.
With targeting data furnished by AV-MF Bear D/F, satellite
(radar ocean surveillance satellite systems) and its own radar and ESM
systems, Bear G can easily prey on any shipping which isn't covered by
an extensive air defence system. The range and speed of the Kitchen
coupled with the Bear G's ability to support it with powerful standoff
jammers enable the aircraft to attack from beyond a vessel's SAM
umbrella. While a USN CBG with its E-2C/F-14/F-18 cover may keep the
Bear at bay, other shipping is extremely vulnerable to this 4,500nm
radius aircraft.
Bear H
The Bear H is the newest strike aircraft in this family and
is
reported to still be in series production at the Kuybyshev plant. This
aircraft is Russia's first cruise missile carrier armed with the new
AS-15 Air Launched Cruise Missile, conceptually similar to the AGM-109
Tomahawk family.
Based upon the late model Bear F airframe, Bear H carries a
J-band Short Horn attack radar and is devoid of most of the blisters
and protrusions carried by earlier versions. The ventral barbette is
absent together with its associated observation blisters but the tail
guns and fire control radar remain. As with the Bear G a small radome
is fitted beneath the refuelling probe.
Bear H also has the large fuselage bomb bay of very early
versions although it appears that much of the aft fuselage was
redesigned, as evidenced by different jointing. The AS-15 ALCM is
carried in the bomb bay (8), under the wing roots (4) and offers
1,500nm class range. It is unclear whether this missile employs some
form of Tercom guidance, as its deployment coincides with that of the
Glonass (Soviet equivalent to US Navstar GPS) satellite navigation
system which would be a far cheaper alternative.
Its accuracy is adequate for nuclear strikes. The Russians
have certainly made a commitment to Bear H as over 40 of this type are
reported in service with the DA VVS and simulated strikes against the
Pacific coast of the US have been flown on numerous occasions over the
last year. It is expected that Bear H will be supplemented and
supplanted by the B-1-like Blackjack A.
Bear J
The Bear J is the latest derivative of the Bear (and was
first
reported in this year's edition of Soviet Military Power). This
aircraft serves as a Very Low Frequency (VLF) communications relay
platform much like the US Navy Tacamo, supporting nuclear ballistic
missile launching submarines. While no details were available at the
time of writing, the requirement for endurance and airframe life
implies the use of new Tu-142M airframes.
Because Bear J must carry a lengthy trailing VLF wire
antenna,
it will almost certainly use the tailcone fairing common to some C, D
and all G aircraft, but in this instance housing the antenna cable drum
and supporting drive and feed hardware. No secondary role has been
attributed to this aircraft but it may function as an Elint platform.
Despite its age the Bear remains one of the key types in the
Soviet inventory, with the DA having roughly 150 aircraft (mainly G/H)
and the AV-MF about 100 aircraft (mainly D/F). By Western standards the
Bear is a dated and unsophisticated airframe with a large infra-red and
acoustic signature and a large radar cross section. It is however
adequate for many of its roles and its 4,500nm class unrefuelled
operating radius is an asset in its maritime reconnaissance and strike
roles.
Hunter-killer pairs of AV-MF Bear D/F aircraft and DA Bear G
aircraft represent a capable sea control weapon system which when
operated from forward bases such as Cam Ranh Bay can cover a large
proportion of the Free World's shipping lanes at extended ranges.
It is surprising that the permanent stationing of eight Bear
D/G aircraft at Cam Ranh attracted so little attention in Australia, as
this will result in an infrastructure capable of supporting deployments
of Bear G strike aircraft at very short notice if required. The haste
with which the Government has proceeded with the Jindalee OTH-B radar
system is not unreasonable under these circumstances.
As a final thought, it is quite paradoxical that the Bear, a
symbol of Soviet global power projection over the last three decades,
is a direct descendent of Boeing's B-29. It is worth remembering.
References:
(1) Taylor JWR, Mason RA, 'Soviet Air Force', Jane's, 1986.
(2) Wiseman CH, 'International Countermeasures Handbook', EW
Communications, 1985.
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