Tupolev TU-126 Moss
Throughout the Cold War the USSR remained behind its western enemies in electronic warfare equipment. The Soviets introduced the Tupolev Tu-126 Moss (NATO Designation) in the late 1960s for airborne early warning missions. The Tupolev TU-126 placed a large rotodome on a modified Aeroflot TU-114 Airliner, itself developed from the TU-95 (TU-20) Bear turboprop bomber first flown in the 1950s. The Tupolev Bear and derivatives have the distinction of being the fastest propeller driven aircraft in the world.
First identified in 1968, Western intellgence believed the Moss entered service in 1971, the exact number used by Soviet Forces being unknown. US sources estimated that only about a dozen of this aircraft were operational throughout the 1980s and the performance of its radar was regarded as inferior to American equivalents. The TU-126 has been assessed by Western sources as being of only limited capability, being unable to detect cruise missiles or small aircraft at low level. The Soviet Air Force relied heavily on ground based direction and radar stations and arrival of the Tu-126 did not alter this. The only point in its favor was its powerful jamming equipment.
The TU-126/MOSS was the f1rst Sov1et a1rcraft used to perfonn a1rborne warn1ng and 1ntercept control. Essent1ally an early warn1ng a1rcraft, MOSS had a 11m1ted capab1l1ty us1ng voice communicat1ons to vector interceptors. Its FLAT JACK radar was not assessed to have a height-finding capabi1ity. The radar can detect and track targets at medium to h1gh altttude, but at low altitudes and in radar clutter was effective only aga1nst large targets. DIA assessed the detection ranges of the FLAT JACK radar, operating at a frequency of 880 MHz aga1nst h1ghflying targets, vary from about 40km for a radar-cross sectton (RCS) value of 0.01 m2, to about 230 km for 10 m2 RCS. Htgher ranges aga1nst larger targets are poss1ble to the maximum unambiguous range.
All nine[?] MOSS were based at Siauliat A1rf1eld in the Minsk Air Defense Distr1ct of the Soviet Union and per1odically deployed to Olenegorsk A1rf1eld on the Kola Peninsula for overwater exercises and tra1n1ng operat1ons. With a radius of 800 km, MOSS had an unrefueled on-station t1me of 7.2 hours.
The three onboard operators were responsible for ident1fy1ng and tracking targets, extracting and forward1ng data to the automat1c control system, and directing f1ghters for interceptions. The levels of prof1c1ency expected for the average operator are s1multaneous d1rect1on of three to seven 1ntercepts and simultaneous tracking of s1x targets. · A trained operator should be able to 1dent1fy about n1ne targets per m1nute. This level of act1v1ty would require a "loose" control - i.e., general vectoring of the interceptor by the A1r Combat Intercept (ACI) operators - as opposed to a "tight" control (i.e. control by the ACI operator unt11 actual weapons release).
The Tu-128 long range interceptor deployment was used to cover awkward eastern approaches to Moscow and to cover gaps toward the interior of the country. The Tupolev fighter was equipped to work with the Tu-114 (Moss) Airborne Warning and Control System. In effect, the radar-equipped AWACS extends the coverage of ground-based control radars. Activities of the AWACS indicated that it was deployed primarily to provide extended coverage of the Northern ocean approaches to the Western USSR. In general, these deployment patterns conform to the distribution of population and industrial capacity in the Soviet Union.
The Northern direction was the probable from which American strategic bombers would attack. Coverage by developing a continuous network of traditional ground environment of radar surveillance presented the most serious problems, since it required enormous financial expenditures and time. The solution was the creation of the mobile systems [DRLO - distant radar detection], placed on an aircraft.
ECM systems on the MOSS provided long-range janming of surface-based a1r surveillance radars, self-protection in the rear hemisphere against fighters equ1pped with I-band airborne intercept (AI) radar, defense against surface-based fire-control systems 1n the forward hemisphere, and jamming against some types of early warn1ng radars and possibly against ground-to-air and air-to-air communications in the VHF/UHF bands. In addition to act1ve janming, a MOSS aircraft emp1oyed four semi-automatic electromechanical chaff dispensers. These were believed to be the self-protection, chaff-release systems used on nearly all Soviet medium and heavy mi1itary aircraft.
The Tu-126 of course possessed far from all of the capabilities of the modern E-3A, but was rather intended only for the early radar detection of aircraft over the sea and submarines and determining their national affiliations. The transmission of data on the targets detected to air-defense command posts was accomplished through special radio-receiving stations. The Tu-126 was in essence none other than a flying radar that was not able to detect targets against the backdrop of the ground. These and other drawbacks were the basis for the actual curtailment of programs to create domestic DRLO aircraft systems in the 1960s.
The shortsightedness of the decision made in the USSR in the 1960s to freeze for a decade the programs to create DRLO aircraft is obvious. It should be said for the sake of fairness that scientific-research work on the creation of the basic elements, problems of processing radar information, determination of the reflective properties of the Earth's surface and the like was being conducted in those years at the initiative of the Air Forces, even in the face of limited financing.
Equipping of MOSS w1th AI and surface-threat radar-jamming capabi1ities indicated that the potential for battlef1eld employment was recognized early in the AWACS program and reflected Soviet plans to have AWACS prepared to support Front operations. Lack of an overland capability in the FLAT JACK radar, however , precluded experimentation in this secondary role. MOSS performance deflciencies in radar and C3 capab111t1es had not dampened the Sov1et cOlllllitment to the AWACS concept. Lack of a look-down capability was the most important deficiency. Detection ranges against small RCS targets needed improvement. Consequently, the MOSS was little more than an early warning platform which can, through voice Communications, vector f1ghters or f1ights of fighters.
At the Taganrog a1rframe plant, the Soviets modif1ed a MOSS w1th a new radar, new rotodome, and a b11ster on top of the fuselage. The functions of the blister were not certain, but DIA believed it may be an antenna for communication by satellite with ground-based camiand-and-control centers. The new rotodome was significantly different from the one on the standard MOSS; it was smaller 1n diameter and appeared s1milar in construction to the rotodome on the American E-3A AWACS aircraft. The Modified MOSS, which has been active in flight operations since at least 1978, was integrated back into the unit at Siau1iat. The Modified MOSS wsa serving as a test bed or equipment and procedures intended for eventual use on the CANDID AWACS. However, DIA recognized the possib111ty that the Modified MOSS had a un1que radar system as compared to the CANDID AWACS and that additional MOSS may be converted to use this radar.
When common sense prevailed in the minds of the "powers that be," it proved possible to create a long-range radar-detection and guidance aircraft — the A-50 — in a relatively short period of time. The development of the A-50, as in the creation of virtually all prototypes of complex technical systems for military purposes, proved to have a revolutionary effect on the development of domestic science and practice.
Early in the 1980s the Beriev A-50 Mainstay began development to replace the TU-126 in service. The Tu-126 was replaced by the A-50 Mainstay during the last years of the USSR. A separate air squadron was formed on the Kola Peninsula, then transferred to the Baltic, and in 1984 it received new equipment based on the 11-76. The aircraft was designated the A-50. With greater capability than the Moss, operational examples began being fielded in the late 1980s and early 1990s.