|The Kursk crew recovery
operation is over, but the Russian officials still can
not say what caused the disaster. The time line of the
accident is taking shape.
Russian nuclear-powered Oscar-II class cruise missile
submarine the Kursk sank on August 12. The
position of the submarine is 69'40 N, 37'35 E, just
outside the cost of the Kola Peninsula east of Murmansk.
The same day, the Northern Fleet completed the
military exercise that started on August 9-10 and
involved around 30 submarines and surface vessels, as
well as aviation.
On August 12, submarines, taking part in the
training, were to carry out a torpedo attack against a
group of combat ships, which acted as the 'opponent'.
The group was under command of the nuclear powered
cruiser Peter the Great that was also the main
target for the submarines. The ships had orders to
follow the south-east course. The attacking submarines
were in 'ambush' along the course. Kursk was one
of the submarines to attack the group being on the alert
in its designated area (15x20 miles in size).
Having assumed the region assigned, the Kursk
sent a radio message to onshore. This report was the
last communication between the operation centre of the
Northern Fleet and the Kursk. Commander of the
Northern Fleet, Admiral Vyacheslav Popov, said this
contact took place at 8:51 a.m. Moscow time on August
According to the training schedule, the Kursk
was to attack the ‘opponent’ firing two practice
torpedoes from 11:30 to 18:00 Moscow time.
Having reported to the operation centre, the
submarine conducted additional surveillance of the
designated area moving first to its southern boarder and
then back to the north-western part.
Kursk went up to the periscope depth of 19
meters to find the 'opponent' ships, which were to enter
the area, at around 11:00. The submarine slowed down to
about 8 knots, extended its periscope, antennas, as well
as, most probably, the device for air intake to fill the
high-pressure air tanks. The available data say that at
that time the 'opponent' was manoeuvring approximately
30 miles to north-west from the area where the Kursk
was on guard. Kursk, playing the rules of this
hypothetical combat mission, could not attack the
‘opponent’ before they entered the area the
submarine was responsible for.
Data from the Norwegian seismological station Norsar say
that two detonations were detected on August 12th. The
first blast, recorded at 07:28:27 GMT (11:28:27 Moscow
time), equalled 100kg TNT.
For the next 2 minutes and 15 seconds, sonar data
from the two US submarines, which were monitoring the
training, showed what appeared to be cavitation, or
propellers going through water, Washington Post,
referring to a US Navy officer, reported last week. The
officer said there was also the sound of machinery
working and ballast tanks being blown in an effort to
bring the submarine to surface.
The most powerful explosion documented at 07:30:42
GMT (11:30:42 Moscow time) had 3,5 points on Richter
scale, ranging between one tonne to two tonnes TNT
Then, according to Washington Post, the only sound
detected was the “creaking” of the hull as it headed
for the bottom. At 240 seconds after the first blast,
the sub was heard hitting the seabed with a crash.
What triggered off the
This question has still no clear answer. Russian
officials suggest that it could be a collision with a
foreign submarine, a mine from the second world war, or
an emergency situation in the submarine’s torpedo
compartment. Unofficial sources say that the Kursk
could be hit by a torpedo-missile launched from the
cruiser Peter the Great.
“Oscar-II” class submarines have four 533mm
torpedo tubes and two 650mm torpedo tubes. The two 650mm
torpedo tubes were reportedly loaded with 65-76 type
torpedoes armed with conventional warheads. Two of the
four 533mm torpedo tubes had USET-80 torpedoes inside
also armed with conventional warheads. The two remaining
tubes were loaded with practice torpedoes. The recent
media reports suggest that the practice torpedoes were
of Shkval class equipped with upgraded propulsion
system. These reports can be relied upon as two
representatives from Dagdizel, the torpedo engine
facility on the Caspian Sea in Dagestan, were onboard
the Kursk. Dagdizel was manufacturing the
propulsion system for Shkval class torpedoes. In
addition, 18 torpedoes and tube-launched missiles with
conventional warheads were in the torpedo room.
Which of the torpedoes exploded first triggering the
more powerful second explosion or whether it was a
torpedo at all is still hard to say.
65-76 torpedo (65cm / 11m) designed in 1976.
The 65-76-torpedo propulsion is based on reaction of
concentrated hydrogen peroxide with water. The
reaction’s output, hydrogen, is pushed under pressure
to turbine. Hydrogen peroxide is contained in a metal
tank inside the torpedo. If a fire heats the hull of the
torpedo, the peroxide starts boiling and explodes.
Experts believe that it takes two minutes for the
torpedo to heat up enough for an explosion. This data is
available from test results. The tests were conducted
earlier so the crew could know how much time they have
in case a fire breaks out in the torpedo section.
USET-80 torpedo (53cm / 7.8m) designed in
1980. Its electric propulsion system was being
manufactured at Dagdizel plant in Dagestan. Torpedo’s
silver-magnesium battery is using seawater as
electrolyte. Dagdizel representatives say the torpedo
can withstand six minutes of fire exposure.
Shkval class torpedo (53cm / 8m) was taken in
use in 1977. Shkval torpedoes are launched with a help
of a trigger that produces gas, shooting the torpedo out
at a very high acceleration. This encapsulates the
torpedo in a gas cavern, easing the water resistance and
allowing it to go at a speed of up to 200 knots (normal
torpedo speed is between 40 knots and 50 knots). It is
believed that the two representatives from Dagdizel,
which were onboard the Kursk, were testing a
modification of Shkval’s propulsion.
Russian military daily, Red Star, published an
article in August saying that the Kursk was
refitted at Sevmash shipyard in Severodvinsk in 1998 to
carry upgraded torpedoes. The newspaper does not say
directly whether these were Shkval class torpedoes, but
the description placed in the article fits Shkval’s
characteristics. The newspaper reported that the Navy
was against the new torpedoes, saying that they were
difficult to store and dangerous to handle. These
protests did not help much, however.
During the operation to recover bodies of crewmen
trapped in the Kursk wreck, a note was found in
the pocket of one of the sailors on October 26. The note
proved that the crew survived the two blasts. The navy
officials said that the note was written between 13:34
and 15:15 on August 12th. The revealed part of the note
said that most of the crew (23 men) from compartments 6,
7 and 8 moved to compartment 9 at 12:58. It also said
that two or three men would try to use the rescue hatch
in compartment 9 to escape. Unofficial reports suggest
that the last entry was made on August 15th.
In an interview with Northern Fleet’s daily Na
Strazhe Zapolyar’ya head of the rescue service of
the Northern Fleet, Alexander Teslenko, described the
following sequence of events.
The Kursk submarine was to attack a group of
surface vessels from 11:30 to 18:00 Moscow time using
practice torpedoes. No report of the attack being
carried out was received from the Kursk, however.
According to the schedule, the submarine was to surface
and report that it was leaving its area of exercise at
23:00 Moscow time on August 12th.
But the understanding that something went wrong with
the Kursk came before 23:00. The rescue
operations chief was called in at 17:00.
Rescue service of the Northern Fleet operates one
tugboat, two vessels, submarine rescue vessel Mikhail
Rudnitsky and rescue vessel Altay. The Northern Fleet
has also three submersibles: AS-34 (Briz) first built in
1986, AS-32, AS-36 (Bester) first built in 1994.
Without waiting for the report to come at 23:00, the
captain of Rudnitsky received orders to have one
hour readiness and was fit to leave the base at 22:20. Altay
was in one hour readiness by that time.
The tugboat was near Kildin Island and was sent to
the area of the exercise at 18:31 and arrived at the
place at 22:30.
The Kursk did not take contact at 23:00.
Teslenko arrived onboard Rudnitsky and the vessel
left Severomorsk, the home base of the Northern Fleet,
in the night from August 12th to August 13th.
At 08:39, Rudnitsky reached the boarder of the
exercise field cut for the Kursk and started
searching for the submarine.
At 12:05, Rudnitsky anchored and began to
monitor the area for radio signals from the Kursk.
The vessel also tried to establish verbal radio contact
with the Kursk crew.
At 15:30, the vessel started preparation of AS-34 (Briz)
submersible. While doing so, Rudnitsky moved to
the most likely point of the Kursk location. At
16:15, AS-34 was put on water. At 16:20, the automatic
acoustic station onboard the Kursk responded to
the probe sent from Rudnitsky. At 17:48, AS-34
caught the radio contact as well and started to
approach. The signal coming from the Kursk was
not too spread to establish the precise location of the
At 18:32, AS-34 had to surface having suffered an
emergency. The submersible likely collided with a
steering wing of the Kursk while being
underwater. After AS-34 had surfaced and was lifted
onboard, Rudnitsky was capable of finding the
precise co-ordinates of the submarine and moved to that
area. The location of the Kursk was established
in 6 hours and 27 minutes after the search party had
dispatched, according the Teslenko.
From August 13th to August 14th, from 22:40 and until
01:05, another submersible, AS-32, was sent several
times down to the Kursk, but it failed to
establish even a visual contact with the submarine.
At 04:00 on August 14th, the batteries ran out at
AS-34. The regular loading time is 13-14 hours. But they
were recharged hastily and the submersible was down at
the Kursk from 04:55 and until 07:48. The
submersible tried to mate with the rescue hatch in the
stern of the Kursk but did not succeed.
On August 14th, at 16:00, another submersible was
brought to the area of the accident AS-36 (Bester). The
submersible was placed on a floating crane tugged to the
area since AS-36’s mother ship, Herman Titov,
was taken out of operation in 1994. But due to the
worsened weather, the rescuers failed to put the
submersible on water – the crane was not designed to
work offshore. The crane was than tugged to the nearest
bay – Porchnikha – to unload the submersible in the
quiet water. The submersible was then towed back to the
area of the Kursk accident having being damaged
on its way in the rough sea.
AS-36 dived again but suffered an accident when one
of the valves, which regulates the trim, developed a
leakage. The submersible had to rest on the seabed for a
while and then to go up in emergency. The submersible
almost sank when it was on the surface, but one of the
cranes managed to grab it.
AS-36 was eventually taken onboard and repaired. It
dived several times after but failed to dock on the Kursk’s
The floating crane was incapable of working in the
sea gale; while Rudnitsky, which was
reconstructed to carry AS-34 submersible from a lumber
carrier, could not provide safe loading and unloading of
the submersible. AS-34 swinging wildly when raised from
water was hitting the board of the ship and received
damages. According to Teslenko, echo sounder, sonar and
other equipment were damaged as a result of the
collisions during loading and unloading.
Teslenko said that all in all Briz and Bester made 14
attempts to dock with the Kursk. None of them was
Norwegian divers opened the rescue hatch in the stern
of the submarine on August 28th - the day after they
arrived. The submarine’s compartments were flooded
with water by that time.