In the beginning, the big volume of the fuselage and a considerable payload were the reasons to convert Tu-114 into a military transport. Tupolev design bureau developed Tu-115, a freighter version. This project was however abandoned because of Antonov An-22, appeared in the same time. An-22 was initially concieved as a transport and therefore better adopted for these needs.
Another project was an evolution of Tu-95 for the navy. Tu-114 was armed with anti-ship missiles and a particular navy radar, and named Tu-114PLO. Finally, this equipment fit into Tu-95 and so Tu-142 was born and Tu-114PLO - abandoned at its turn.
There were some other military versions, but only one arrived to the production: the AWACS Tu-126.
The most probable direction of a supposed US attack on the USSR was North. Covering the North of the USSR with a dense radar network was an impossible task. The only found solution was a deployment of a mobile network with AWACS planes as nodes. On July 4, 1958, Tupolev design bureau received a government demand on such an aircraft that also took part in the global re-organisation of the USSR air defense. The official document N°608-293 issued by the government specified the characteristics of the AWACS plane: capability to stay airborne up to 10-12 hours, practical ceiling 8000-12000, maximal detection distance : 100km for fighters, 300km for bombers, maximal retransmission distance : 2000km.
In the end of 1958, the detailed characteristics were specified and the design bureau (OKB-156) started working on the project. The radio detection unit "Ozero" (Lake) has been chosen to be mounted on the aircraft. The bureau experimented mounting the equipment on a Tu-95. When the engineers understood that all the equipment cannot be fit in a Tu-95, they turned to Tu-116 that disposed of quite a big pressurized passenger cabin. However even this plane was too small for the task. Finally, Tu-114 was chosen considering the place it offered inside.
This choice solved many problems at a time: all the electronic devices got sufficient place in the pressurized cabin. There were enough space for cooling units. The equipment could be easily accessed for maintainance. It also became possible to carry another complete crew that relayed the first one after 6 hours of flight. Finally, the exceeding space could be used for future extra equipment. Military authorities were some time insisting on using Tu-95, but finally the advantages brought by Tu-114 convinced them and they changed their mind.
On January 30, 1960, the general shape of Tu-126 was specified. At this moment, a newer detection station "Liana" appeared and quickly became the major unit of all the air defense network. Obviously, it was decided that Tu-126 will integrate "Liana" on board. The development of the plane was managed by N.Bazenkov, with participation of A.Putilov.
In the beginning of the 1960-ies, the system "Liana" was a technical miracle and the hi-end of the existing detection techniques. It detected aircraft up to 100-350km (depending on their size), cruisers - up to 400km. The retransmission was assured, as specified, up to 2000km. To ensure a complete 360° view, the antenna has to be mounted 2.6m over the fuselage and rotate 10 turns/min. Two solutions were proposed: a rotating antenna in a fixed aerodynamic case and a rotating aerodynamic case with the antenna fixed inside. A.Putilov proved that the second solution offered less weight. Thus, Tu-126 became the world's first AWACS aircraft with a rotating plate. Later, this configuration was copied by other countries.
Considering the dimensions of the "plate" - diameter 11m, height 2m, there was no problem to assure an easy access to the antenna for maintainance from inside the plate. During the development, some changes have been made to the initial structure. The backfire guns occured inadopted to this kind of aircraft, so it was decided to remove it and thus remove the gunner's place in the middle of the fuselage. Another detection system - RTR - was mounted in the vacant section - it allowed to detect working radars up to 600km. The detection crew was slightly changed. It contained then: the chief, "Liana" operators, RTR operators, encoding operators, technical stuff for in-flight maintainance. Some of the sections have been protected with special screens from the powerful electronic emission from the rotating antenna. Astro-navigation sextants were placed above the first section.
Tu-126 was highly resistant to attacks. It couldn't be attained by missiles designed to destroy static locators and guided by the locator itself. It was difficult to touch it with "air-to-air" and "ground-to-air" missiles because the aircraft carrying them were detected long before they can launch the missiles. Moreover, "Liana" wasn't emmiting permanently, but alternating emmision and radio silence. During the silence, only RTR passive radars were switched on.
An important part of the testing was the testing of "Liana" equipment. Tu-126 showed its capacity to detect high-altitude targets, which wasn't primary specified. It successfully selected targets on ground and airborne over Barents and Karsk seas.
An imortant addition was supplying Tu-126 with refueling equipment. It was tested on August 29, 1967 on the unit 66M622. After the successful testing, this equipment was installed on all production units. It came without changes from Tu-95 (namely Tu-95RTs and Tu-95KD).
Three aircraft - 65M611, 66M613 and 66M621 - were carrying baits containers in the rear part of the fuselage. Starting from 67M622 (and also 65M612), the rear part was stretched and occupied by a rear radar SPS-100 "Rezeda".
After long testing and a number of improvements, Tu-126 entered military service on May 15, 1965. The first unit was delivered to the airbase N°32457 near Shauliai (Lituanian Republic). Later, all the delivered Tu-126 were affected to this base. They formed two squadrons of 4 units in each. The first prototype didn't take part in any of the squadrons and even didn't have a permanent crew. It served most of all to test novelties.
Nine aircraft were produced:
Considering the specifity of Tu-126 construction, its pilots were all piloting Tu-95s in the past. Later, pilots too old to fly supersonic fighters, were also admitted to pilot Tu-126. For them Tu-126 was a pre-retirement stage and they hoped to stay in Shauliai after the retirement, as it was a very pleasant place to live.
In practice, Tu-126 could only accomplish two tasks: targets detection and following and RTR radio intelligence. The obtained data was transmitted to Vaskovo near Arkhangelsk and to Severomorsk, then routed to Moscow and distributed to all air defense system by the network "Vozduh-1". Tu-126 recognized the belonging of the target (friend/ennemy), the coordinates and the altitude of each target. The maximum number of followed targets was 14. At service altitude 8000m, the detection range was 420km.
The usual Tu-126 routes lied from Shauliai over Leningrad and Arkhangelsk either to Novaya Zemlya islands, or to the Land of Franz Joseph. The flights last 8.5-9h. Another route passed through Baltic sea, sometimes - along the western border to Black sea. 1 to 4 planes were always patrolling. Few days - no one, but there was always at least one ready to takeoff.
Every summer, two of the planes were sent to Olenogorsk base in the North. There, Tu-126 could fly far beyond Novaya Zemlya islands and it was training joint work with Yak-28 and Tu-128.
The flights were all the same: just after the takeoff, "Liana" was switched on for heating. At 7200-8000m it was switched to emission. The locator was active almost until the very landing. Two radio crews and one flight crew were boarded. If the flight included refueling, a pilot, a navigator and a flight engineer were added to the flight crew. The squadron counted at least 7 crews able to refuel in the air. However, after 1979, the refueling was no longer practiced because the army didn't have enough tankers (3MC-2).
After the ressource expiry, all the Tu-126 were retired in 1984.
Obviously, no training could raise Tu-126 to the new level of capacities necessary in the 1970-ies. The USSR air defense needed another system to detect low-flying targets. The newer locator "Shmel" (bumble-bee) had to be mounted twice as high as "Liana". Tupolev design bureau proposed a project called Tu-156, that was quite similar to the american AWACS E-3A. To fit all the equipment, the forward part of the fuselage was higher, making the plane look like Boeing 747. The plane was well armed, contrary to Tu-126.
Nevertheless, the project was rejected by the governement. It required that the new AWACS should be based on a production aircraft. Finally, the winner was the quadrijet Il-76 and the detection equipment was added in Beriev design bureau, creating the new generation AWACS: A-50 that is still in service.
Refuel Panel
To show the panel, press "Shift+3". It is also automatically shown when you switch to the second pilot's view.
Other new switches:
Liana Radar
Tuesday Engels - Semipalatinsk - Airbase Belaya Z25A - UA0F - UIIB Z25A (01:08:00) - CONTACT (Time: Tue 03:29 UTC, Loc: N52* 1.38', E66* 20.83', Head: 86, FL230, Speed: 247 kts) UA0F (05:02:00) (int) - CONTACT (Time: Tue 06:14 UTC, Loc: N51* 54.68', E89* 6.20', Head: 74, FL230, Speed: 247 kts) UIIB (07:51:00) |
Wednesday Airbase Belaya - Tiksi - Airbase Belaya UIIB - UEST - UIIB UIIB (10:05:00) - CONTACT (Time: Wed 12:33 UTC, Loc: N64* 42.27', E114* 36.64', Head: 43, FL220, Speed: 247) UEST (14:04:00) (int) - CONTACT (Time: Wed 15:51 UTC, Loc: N64* 50.92', E114* 35.23', Head: 220, FL220, Speed: 250) UIIB (18:00:00) |
Thursday Airbase Belaya - Engels UIIB - Z25A UIIB (04:07:00) - CONTACT (Time: Thu 07:22 UTC, Loc: N55* 43.22', E73* 12.67', Head: 253, FL220, Speed: 247) Z25A (10:14:00) |
Friday Engels - Semipalatinsk - Airbase Belaya Z25A - UA0F - UIIB Z25A (11:14:00) - CONTACT (Time: Fr 13:35 UTC, Loc: N52* 1.38', E66* 20.83', Head: 86, FL210, Speed: 247 kts) UA0F (15:08:00) (int) - CONTACT (Time: Fr 16:25 UTC, Loc: N51* 54.68', E89* 6.20', Head: 74, FL210, Speed: 247 kts) UIIB (17:58:00) |
Sunday Airbase Belaya - Engels UIIB - Z25A UIIB (01:00:00) - CONTACT (Time: Sun 04:17 UTC, Loc: N55* 43.22', E73* 12.67', Head: 253, FL220, Speed: 247) Z25A (07:07:00) |