667A YANKEE I
In 1958 OKB-18 started the development of a new ballistic missile submarine. Initially work was undertaken on two versions, of which only one was authorized. A.S. Kassatsiyer, the author of both versions was designated as chief designer. The development of the submarine faced significant problems regarding the launch system. During elimination of the problems the project underwent fundamental changes and as a result the completely new submarine design received the new designation 667A. The new chief designer was S. I. Kovalev. The revised 667A submarine was both developed and authorized in 1962.
The external contours of the submarine were designed to achieve minimal resistance when operating under water. Unlike previous submarines, the horizontal hydroplanes were arranged on the sail. The cylinder-shaped pressure hull is divided into 10 compartments and has an exterior diameter of 9.4m.
The SSBN 667A is equipped with the D-5 launch system and 16 R-27 missiles with a range of about 2400 km. They are arranged in two rows in the fourth and fifth compartments. The missiles can be launched from a depth of 40-50 meters below the surface, while the submarine is moving at a speed of up to 3-4 knots. The missiles are fired in four salvos each comprising four missiles. The time needed for pre-launch preparation is 8 minutes, and within a salvo the missiles are fired at intervals of 8 seconds. After each salvo the submarine needs three minutes return to the launching depth and between the second and third salvo it takes 20-35 minutes to pump water from the tanks into the launching tubes.
The primary propulsion machinery includes two self-contained units [port and starboard], each of which consists of a pressurized water reactor reactor, and an independent turbogear assembly. The maximum speed when submerged is 27 knots. The auxiliary propulsion motors can be used for torpedo firing, to maintain electric power during emergency and provide for stand-by capability of the boat while on the surface.
To reduce the noise of the submarine special propellers were created, the pressure hull was covered with sound-absorbing rubber and the external hull was covered with a antihydroacoustic coating. The footings under the main and auxiliary propulsion systems are also isolated by a layer of rubber.
The 667A SSBNs were equipped with the "Cloud" battle management system which could receive signals up to a depth of 50 meters with the help of the towed antenna "Paravan." The first four 667A Yankee submarines employed the "Sigma" navigation system whereas the follow-on ships were equipped with the "Tobol" -- the first Soviet navigational system that used a satellite navigation system. This system provided reliable navigation in the Arctic Region and in the Pacific Ocean and also sustained the operational capability of the missiles at high latitudes down to 85 degrees.
The first 667A Yankee submarine, with the tactical designation K-137, was launched in 1964 at the Northern machine-building enterprise in Severodvinsk. In July 1967 the submarine "K-137" completed sea trials and at the end of 1967 it was introduced into the Northern fleet. Between 1967 and 1974 a total of 34 strategic submarines of the 667A class were build. 24 submarines were launched in Severodvinsk and 10 in Komsomolsk na Amure.
In 1972-1983, the Yankee submarines along with older submarines were re-equipped with the D-5U launch system and R-27U missiles. The R-27U missile had a greater range -- up to 3000 km -- and carried multiple reentry vehicles. The upgraded submarine was designated as 667AU.
In 1967 the first 667A ballistic submarines to form part of the Northern fleet were incorporated into the 31st division of strategic submarines, which was based in the port of Sayda. At the end of the 60s the 19th division of strategic submarines was also equipped with 667A submarines. Both divisions formed part of a structure consisting of 12 squadrons, which in December 1969 was transformed into the 3rd flotilla of submarines.
Two divisions of 667A submarines of the Pacific fleet — 8th and 25th- - were based at Kamchatka. In the middle of the 1970s a unit of 667A SSBNs was transferred to Pavlovsk.
In May 1974, near the Navy base in Petropavlovsk a ballistic missile submarine of the 667A class collided with the American attack submarine "Pintado" (SSN-672) in a depth of about 65m. The Soviet submarine was only lightly damaged.
On 03 October 1986, on board of the ballistic missile submarine "K-219" of the 667AU class an explosion took place that sparked off a fire. The cause was a depressurization of the reactor pit. The submarine was located 970 km east of the Bermuda Islands. The crew of a boat managed to surface the submarine and muffle the reactors. As a result of the accident four people were killed. The submarine was towed but on 06 October it had to be scuttled into a depth of 5,500 meters. The United States Navy normally does not comment on submarine operations. But the US Navy issued a statement regarding the release of the book "Hostile Waters" and an HBO movie of the same name, based on the incidents surrounding the casualty of the Russian Yankee submarine K-219. The United States Navy "categorically denies that any U.S. submarine collided with the Russian Yankee submarine (K-219) or that the Navy had anything to do with the cause of the casualty that resulted in the loss of the Russian Yankee submarine."
Between 1979 and 1994, all Yankee submarines were removed from operational status and their missile compartments cut out to comply with arms control agreement ceilings. During their operation time the 667A and 667AM Yankee submarines had carried out 590 patrols all over the world. Two of the submarines were taken out of service in 1979, two in January 1980, one in January 1981, two in January 1982, one in November 1982, one in June 1983, one in January 1984, two in April 1985, two in March 1986, two in 1987, and the rest in 1988 and 1989.
A number of Yankee ballistic missile submarines were modified to perform other missions.
- In 1977 the "K-140" submarine was equipped with the first D-11 Soviet sea based solid-fuel missiles and received the designation 667AM Yankee II. The 12 P-31 missiles loaded on the submarine could be fired from a depth up to 50 meters. The torpedo tubes could be reloaded in less than in one minute using a "dry" launch technique. Its submerged displacement increased to 10,000 tons.
- The submarine "K-420" was converted to test the "Meteorite" (SS-N-24) cruise missiles. The re-equipped submarine received the designation 667M ANDROMEDA (Yankee SSGN or Yankee Sidecar). The length and the width of the SSBN were increased up to 153 m and 15-16 m respectively. Outside of the pressure hull 12 launchers for the SS-N-24 missiles were located. The re-equipment began in December 1982 and the first launches of a cruise missile was conducted in December 1983.
- From 1982 to 1991 some Yankee I SSBNs were equipped with 20 up to 40 launchers of SS-N-21 "Grenade". They were designated as 667AT (Yankee Notch). Unlike the "K-420" that was converted to carry the SS-N-24 missiles, the shape of the deck behind the cabin was not altered. The displacement of the submarine was increased up to 11,500 tons and the body was lengthened to 140 meters.
- From 1979-1984 the ballistic missile submarine "K-403" was converted into a submarine for special purposes designated as Yankee Pod. Instead of a missile compartment, it had was equipped with radio equipment and a towed hydroacoustic station.
- In 1990 the SSBN "K-411" was converted under the project 09774 (Yankee Stretch) into a carrier of supersmall "KS-411" submarines.
Between 1988 and 1994, most converted Yankee submarines were removed from operational status. The converted K-411 (Yankee Stretch) and K-420 (Yankee Sidecar) are reliably reported to remain in service, and some reports also suggest that K-395 [a Yankee Notch] and K-403 [Yankee Pod] may also remain in service.
