Project 661 Anchar (NATO Papa)

Soviet SSGN: K-222 1970-1988

K-222 was the unique Project 661 “Anchar” (NATO “Papa class”), a nuclear-powered cruise-missile submarine developed and bult by the Soviet Navy during the Cold War. She was developed before the Alfa class SSNs as a new generation titanium-built record speed submarine. Development and construction took a decade, but she was successful indeed upon completion, as the world’s fastest submarine, first built with a titanium hull, pioneering the way before Project 705 Lira. But in the end, she was unsuccessful as a production submarine between her excessive noise, complexity and cost overall. She was laid down as K-18 but renamed K-162 at launch and K-222 in 1978.

Development

The large SS-N-3 Shaddock family was a first soviet production missile that had a lot of issues, especially compared to the latest US missiles and compensated by a longer range and much heavier warhead. This missile also needed to be launched from the surface and had a constraining target-acquisition process forcing the lanunching submarine to stay surfaced and guide the missile up to the target. The ECHO I and II were at the time, the only Soviet SSGNs in service and they were not immensely successful between their noise and problemati nuclear reactors, in addition to their missiles.

The Council of Ministers issued a resolution on 28 August 1958. They looked for a very ambitious development program calling both for a replacement missile and its carrier, a new missile submarine with double the speed, twice as much diving depth, all with smaller nuclear reactors and better automation. The new long-range missile system of small dimensions was also to be fired while submerged. On way the engineers were able to pull this off when choosing a challenging materiala and make a titanium hull, a world’s first.

Design bureau TsKB-16 started development of Project 661 based on the TTZ (specifications). This was not intended for production, as there were just too many innovations for a single project, and instead it was to be an experimental platform of cruise-missile submarine, solving a series of techonological issues in response to the resolution. Chief designer N. N. Isanin started from a clean-slate design using relatively little existing technology (which explains the final cost and duration of the program). By July 1959, a sketch design was ready, with impressive planned specs such as a top speed of 38 knots (70 km/h; 44 mph).

The State Committee for Shipbuilding had to take decisions about the hull construction, as titanium was still not firmly decided yet. At first indeed, aluminium or a steel-aluminium alliage were discussed. Titanium was a challenging material to say the least, see the Alfa class development for more. The choice of nuclear reactor that would be used was also a challenge as it needed to be smaller and yet more efficient. Some argued for the same development as the (Project 705 Lira/Alfa class) with a metal-cooled reactor, that could produce immense amounts of power for a smaller package, but it went with its own sets of technological challenges and it was decided against in the end.

Aluminium was quickly rejected as unsuitable eventually due to its poor resistance to corrosion and poor performance under high pressure at high speeds. This material was suited for aviation but definitively not for great depths. It was looked also new steel alloys, still under development. In the end, titanium had many advantages as a material, it had a much stronger resistance than steel for its weight, and resisted corrosion better while being non-magnetic. In aviation, it was also pushed forward at the same time resulting in the latter Mach-3 capable Mig-25 Foxbat fighter.

The titanium hull was also ideal to protect the submarine against magnetic mines as well as not registering on magnetic anomaly detectors (MAD) used by US and NATO anti-submarine patrol aircraft. The greatest issues which were raised, were its high cost compared to steel, and impossibility to weld it in an oxygen atmosphere. In the end, like for the Pr.705 Lira program, the committee selected Titanium despite the odds. Two types of reactor were looked after, the now “classic” pressurized water model, or a lead-bismuth eutectic model (metal liquid, later chosen for the Alfa class). The first was known, not much the second, and it proved to be a deciding factor. The committee was not ready to wait for the lead-bismuth reactor to end its development cycle despite its advantages in size, weight and power ratio. K-222 in the end would have classic PWRs but she would be however the first submarine built with a titanium hull.

These decisions produced a design with an underwater speed of 38 knots and still able to carry an launch ten to twelve missile launchers forward of the sail. The final plans ended larger than the specified displacement with two propeller shafts, after the committee considered a single shaft but rejecting based on unreliability grounds at the time for 1st-gen PWRs. They looked indeed at the redundancy of two reactors or a second generation. The auxiliary diesel generator for earlier SSNs was eliminated to compensate. The final sketch design and its authorized preliminary design work was accepted in February 1960. The final design was validated by May of that year. To reduce technical risks, the navy intervened and proposed to modify five existing submarines to test systems used on project 661. One of these was the P-70 Ametist (NATO SS-N-7 Starbright/4K66) missiles, but other submarines tested the sonars and other systems. Unlike the Alfa class, it was also decided to reduce the level of automation compared to the later Alfa class to make things easier. In many ways, the Papa class was more conservative than the Alfa that followed.

Design of the class

Hull and general design

K-222 had a classic double-hulled design displacing 5,197 metric tons (5,115 long tons) surfaced and 7,000 t (6,900 long tons) submerged. Its overall length ended much superior to all previous Soviet submarines but the ECHO-II at 106.92 meters (350 ft 9 in) for a beam of 11.5 meters (37 ft 9 in) and draft of 8.2 meters (26 ft 11 in) giving it a good lenght/beam ratio. The inner hull had nine watertight compartments with an unusual configuration at the bow with two compartments being narrower and superimposed in a “8”. The upper one housed the torpedo tubes and the lower one the massive sonar system and batteries. The third compartment was narrow as well at 5.9 m (19 ft 4 in) but the others were 9 m (29 ft 6 in) wide. K-222 managed the greatest test depth of its class at 400 meters (1,300 ft) with a design depth of 550 meters (1,800 ft). To compare, the later Alfa class dived deeper at 800 m max (2620 ft). The crew amounted to 82 officers and enlisted men.

Powerplant

Project 661/Papa had two shafts, on which ere mated two 177.4-megawatt (237,900 hp) VM-5M reactors. Their steam circulated to the GTZA-618 steam turbine, driving the shafts. The turbines managed an output of 80,000 shaft horsepower (60,000 kW), intended to propel K-222 at 38 knots. It had two 3,000-kilowatt (4,000 shp) turbogenerators and ti feed them, two 152-cell silver-zinc batteries fitted in place of a diesel generator. This made her quieter than previous boats in submerged mode and she still achieved 25 knots (46 km/h; 29 mph) surfaced. Underwater, she proved to be much faster than the 38 knots originally setup, at 42 knots (78 km/h; 48 mph), at 90 percent power in sea trials by December 1969. She made a 12-hour full-speed test in which some of her external hull fittings were ripped off while her water intakes grilles broke loose and were ingested by the water-circulation pumps. A report on sea trials noted:

The biggest thing was the noise of the water going by. It increased together with the ship’s speed, and when 35 knots (65 km/h; 40 mph) was exceeded, it was like the noise of a jet aircraft. … In the control room was not heard simply the roar of an aircraft, but the thunder of “the engine room of a diesel locomotive”. Those present believed that the noise level was greater than 100 decibels…

Needless to day, not great for acoustic discretion… In another trial in 1970 at full power, K-222 reached 44.7 knots (82.8 km/h; 51.4 mph), this time to setup a world record, that was homologated internationally as the fastest speed attained underwater by a manned object. A record that still stands today. Since then, rockets torpedoes like the Shkval broke this record, but they are unmanned. To keep things into perspective, the classic defensive USN torpedo of the time, the acoustic Mark 46, first generation, was only capable of 40 knots (74 km/h; 46 mph) and less than 1000ft in depth. The USN in reaction developed the Mark 48 capable of 55 knots (102 km/h; 63 mph) over 24 miles, but capable of greater depth. The Project 661 carried enough supplies to stay at sea for 70 days albeit her range was unlimited. One solution to keep her at sea longer was a swap of crews operated at sea from a supply ship. This was never implemented in practice.

Armament

The Project 661 had a dual armament, classic torpedoes, but its main assets were ten P-70 missiles in individual tubes placed between the inner and outer hulls, forward of the sail.

P-70 Ametist (NATO SS-N-7 Starbright)

The GRAU 4K66, П-70 «Аметист» was a cruise anti-ship missile deployed on Project 661, Soviet and Indian Project 670 (Charlie class). It was succeeded by the P-120 Malakhit (SS-N-9 ‘Siren’). When entering servive on June 3 1968, it was the first anti-ship missile system in the world to be launched from a submerged submarine. From 1968 to 1987, a total of 631 missiles were built.
The tubes were positioned upwards at an angle of 32.5 degrees, each using four solid-propellant boosters, launched underwater at 30 m (98 ft) max. The fire system prevented that more than five missiles could be fired in a single volley, with the the second volley fired after three minutes preparation to track the missiles once on their first leg until their radar took over.

The P-70 could be launched from under 30m (98 ft), guided on its last leg by its own L band active radar homing sensor and radar altimeter developed for the P-120 but smaller. It had no datalink. It was launched with folding wings deployed afterwards but was criticitzed for its short range and absence of mid-course updates. About 200 were produced. Its low altitude of 30m made it difficult to detect though. Its RCC radar homing system had automatic target selection to pickup the “largest reflective surface” generally the aircraft carrier in the group. The Papa class carried more than the latter Charlie I (8) and typically two missiles had nuclear warheads. It could be launched at sea state up to 5 points

⚙ specifications P-70 Ametist

Weight: 7,700 lb (3,500 kg), dimensions 23 ft (7 m)
Propulsion: Solid fuel, Mach 1 (1,160 km/h), range 65 km (35 nmi), ceiling 50-60 m
Payload 1,170 lb (530 kg) High explosive/200 kiloton nuclear
Guidance: L band active radar homing sensor and radar altimeter

Torpedo Tubes

The narrow bow compartment above the sonar saw K-222 fitted with just four 533 mm (21 in) torpedo tubes, but with eight reloads. They could be fired down down to 200 m (660 ft) if needed.

⚙ 53-65M (1969)

Acoustic wake following homing torpedo derived from the 53-61 torpedo. Weight 4,630 lbs. (2,100 kg), 283 in (7.200 m) long, warhead 661 lbs. (300 kg). Range/Speed 24,000 yards (22,000 m)/44 knots, powered by a Kerosene-Hydrogen Peroxide Turbine.

⚙ TEST-68 (1969)

First Russian wire-guided torpedo, derived from SET-53M. Active/passive acoustic homing 880 yards. Capable of 650 feet (200 m). Weight 3,307 lbs. (1,500 kg), lenght 311 in (7.900 m), 220 lbs. (100 kg) warhead. 15,300 yards (14,000 m)/29 kts, Silver-zinc battery.

Sensors

Sonar

The Rubin MGK-300 sonar system occupied the full nose at the “jaw” or at the lower inner hull, measuring 6 m (19 ft 8 in) in diameter, 3 m (9 ft 10 in) in height. It was fitted with active and passive transducers to detect large and noisy carrier battle groups at long ranges. Range estimations were initially of 14.8 km. It would transmit data to the missiles for its initial targeting, locating them at 50 kilometres (31 mi; 27 nmi) with mid-course updates for the missiles in flight if attacking further away. Later upgrades to the sonar enabled to reach a range of 70 km (43 mi; 38 nmi), the actual range limit of the P-70 missiles. Once fired, the P70 could adjust course of its own thanks to its active radar.

Albatros RLK-101 Radar

K-222 was fitted with an Albatros RLK-101 search radar (NATO Snoop Tray) in addition to a Molniya (NATO Pert Spring) satcom (satellite-communications system). This, too was formidable leap forward compared to the Echo II. She also had a star inertial navigation system. The Albatros was a pulse-Only Radar for when surfaced for search at short-Range (37 km) so used also for navigation.

⚙ specifications
Displacement	5,197 t (5,115 long tons) surfaced, 7,000 t (6,900 long tons) submerged
Dimensions	106.92 x 11.5 x 8.2m (350 ft 9 in x 37 ft 9 in x 26 ft 11 in)
Propulsion	2 shafts steam turbines, 2 nuclear reactors 80,000 PS (59,000 kW)
Speed	25 knots (46 km/h; 29 mph) surfaced, 44 knots (81 km/h; 51 mph) submerged
Range	Unlimited, autonomy 70 days
Armament	10 × SS-N-7 Starbright (P-70) CruM, 4× 533 mm (21 in) bow TT
Test depth	400 m (1,300 ft)
Sensors	Rubin MGK-300 sonar, Albatros RLK-101 search radar
Crew	82

Career of K-222 and evaluation

Project Origin

The Soviet Navy was dissatisfied with the Echo class given their obligation to surface after firing their missiles to guide them top the target, exposing them. So by 1958 a replacement was planned with a quite -some would say exceedingly- ambitious program. Requirements for a very fast, very deep diving nuclear-powered submarines with a brand new generation of autonomous cruise missiles launched while submerged and new generation or PWRs piled up. It took two years of research before construction started in 1963 and work proceeded very slowly due to titanium welding techniques being largely experimental at least at that scale. It required sealing of the entire building and forced all workers, the best qualified in the Soviet Union, to work with full breathing apparatus.

New ways of working titanium on such a scale were to be invented, and in the unusual Soviet manner, quality control was inconsistent. The objectives of the program were generally satisfied in the end, but the government failed to include a requirement related to the acoustic signature. This exonerated the builder and engineers of all responsibility about the latter, and K-222 would be regarded as a speed record setter but completely impractical as an operational submarine. The noise level was one of a jet underwater, K-222 would proved easily detectable at high to moderate speed dozens of miles around.

The Soviet Navy based on this, was impressed by the technical solutions found for this model, but obviously rejected series production. K-222 flaws outweighed its advantages, but it was considered a pioneer for many technology and the choice of classic PWR reactors gave her a far longer career than the Alfa class, doomed essentially by the need to heat up their metal liquid reactors at all time and lacking shore facilities to assist. The technology needed to work with titanium on such a large scale enabled subsequent construction of more successful designs like the Projects 705 Lira, 945 Barrakuda, and 945A Kondor, probably its greatest legacy.

Evaluation in short

Commissioned in 1969, K-162 (first name) had ten short-range, anti-ship cruise missiles of a new generations capable of be launched underwater and with autonomous guidance for their final run. The four torpedo tubes were almost an “insurancy policy” against any bad encounter, but her primary mission as a concept was to destroy US aircraft carriers. Since production of Project 622 was denied, the missiles and othr percs from this project were passed on to the Charlie class. These P-70 missiles could be fitted with nuclear warheads in wartime, but it’s dubious the Papa class ever had any. K-162 served in the Soviet Red Banner Northern Fleet in the seventies until the discovery of hull cracks led to a long refit from 1972 to 1975. After being renamed K-222 it was not long before its early types of reactors causes troubles. There was a nuclear reactor incident in 1980, and it was decided she would do her final operational patrol in 1981. She then acted as static testbed for various innovations until removed from service in 1988, then mothballed until scrapped in 2010.

Construction challenges

Construction was indeed something daunting, as large-scale fabrication of titanium was unknown at the time. Nobody tested it on a large scale, only small experiments. Techniques and equipment had to be invented fro scratch. The Soviet Government footed the bill, and this was eye-watering. The Sevmash shipyard invested in new equipments to handle this, shaping plates up to 60 mm (2.4 in) thick while training its worried workers to weld in an argon atmosphere in a perfectly sealed, cleanroom environment preventing any contamination of the welds. That process started with experimenting with the first two half-scale sections. One was for testing this in a pressure chamber, the other to evaluate shock resistance in Lake Ladoga. The collapse of the section under hydraulic pressure and cracks in the welds revealed that the welders at Severodvinsk failed to apply strict cool down time requirements, perhaps under pressure of the management to meet the deadlines. Metallurgical experts were consulted and reached the conclusion that the steel tools themselves were an issue, not suitable to deal with titanium and had to be replaced.

The first definitive titanium plates were delivered in late 1961, allowing K-18 as it was initially known, to be assembled. She was laid down on 28 December 1963 and renamed K-162 prior to launch on 27 January 1965. Construction dragged on due to the delivery of plates for the outer hull by the Kommunar Metallurgical Plant, contaminated by hydrogen. They cracked easily. 20% of these had to be replaced, and she remained on slip until her final launch on 21 December 1968. Testing soon revealed that she had 10 ballast tanks not watertight, despite previous careful examination. Non-titanium components as it was discovered, were not properly isolated from the titanium hull and that caused corrosion. K-162 before even its commission was soon nicknamed by sailors the “Golden Fish”, in reference to her staggering cost.

A relatively short career (1969-1988)

Commissioned on 13 December 1969, K-162 was assigned to the Soviet Red Banner Northern Fleet and spent most of the next two years under tests and sea trials. Her first “operational” patrol was in the North Atlantic in September–December 1971, where she probably drew a lot of attention of NATO ships and subs around. During this patrol, she trailed USS Saratoga‘s battle group at high speed as it returned from deployment to the Mediterranean. She had long refit from October 1972 to January 1975 and when drydocked, inspection revealed many cracks in both her outer and pressure hull, that required repair. Three years later she was renamed K-222 to confuse NATO analysts.

It was planned for a time a revised version for mass production, but the conclusion was that concluded that the design would have to be modified so much, with longer-range missiles, more torpedoes and silencing measures that a brand new model made as much sense. The excessive noise at high speed nullified any possibility of the sonar system acquiring targets. This needed to be remedied. Her high cost and long refit time, with increasingly limited resources forced the navy to decide she would remain alone. Thus, design studies for derivatives like the improved Project 661M, Project 661A firing the P-120 Malakhit/NATO SS-N-9 Siren, and Project 661B firing the R-29 Vysota/NATO SS-N-8 Sawfly) ballistic missiles were all decided against. K-222 was not an overall successful design by itself, but the technology developed for her led to the construction of the Alfa-class and the more successful, albeit still short series Sierra-class. By the early 1980s, the need for high speed was no longer so stringent as to continue using titanium, especially for large production SSN, such as the Akula, which improved on the more conventional Victor III instead.

K222 end of career was not glomorous. She saw her reactor refueled in November 1980, but the crew lost the unique tools needed to handle the nuclear fuel rods at the Severodvinsk facility and instead of face blame or worst, they had to refuel her without them, leading to a “a la russian” procedure, with the entire crew on lunch ashore on 30 November against naval regulations, leaving shipyard workers aboard without guidace and unable to active the automatic safety system to control the rods when shut down. They started to lift, and that caused a surge without any water flowing to cool down its core. Since no worker was monitoring the core’s temperature, a work for the responsible engineer now left ashore, the situation degenerated until an alarm sounded after a condenser ruptured, with radioactive steam and water entering the machinery compartment.

Workers sent someone fetching the crew, while one of the workers was able to prevent the steam from spreading, turning on the main pumps to get water cooling the core, avoding further incidents. The incident trigerred a commission which investigation led to recommendation to replace the new worn out, obsolete reactors by 3rd gen. ones and that an emergency diesel generator be installed. However the cost prompted the navy to reject these and just repair the damage, decontaminate the compartment. Once done, K-222 made her last operational patrol in 1981, not doubt her reputation led to some reluctance from the engineering crew to board her.

papa in 1983
The fate of K222 is unclear from there. Russian sources states she was inactive from 1982 onwards, without much details. It seems she was simply mothballed and used for static tests until 1988, then placed in reserve at Belomorsk, close to Severodvinsk. Since the crew never retrieved the tools to handle the fuel rods, the navy failed to find anybody to defuel her and she remained in the mothballed until the end of the cold war, and years afterwards. By 2008 at least, an inspection revealed cracks in the hull, with the ballast tanks starting to fill. To avoid her sinking, in March 2010 Sevmash started scrapping her with the reactors and nuclear fuel still on board unlike the common procedure. This work was completed by 4 June. The nuclear compartment was stored, seemingly still with the rods in place, but the fuel probably removed. In Tom Clancy famous “Red Storm Rising”, the K222 Papa is sunk by Jerry “The Hammer” O’Malley, flying an ASW helicopter from USS Reuben James, while attacking a convoy.