34.7
Investigation Report on Possible Explosion Damage on the Ferry "Estonia"
by Brian H.L. Braidwood, MBIM, MIExpE, Weymouth/UK

At the beginning of this subchapter the Estonian managing director of Estline, Johannes Juhanson, shall be quoted when he told the Estonian media on 29.09.94:

"Estonia" was sunk by an abnormal factor, an explosion or an underwater collision.

In February 1999 Brian Braidwood was requested by this 'Group of Experts' to look into certain aspects of the casualty in his capacity as diving and underwater explosives expert, in particular to investigate whether explosive devices were present on board the ESTONIA and had caused damage when they exploded before the sinking of the ferry.
After a very careful investigation Brian Braidwood concentrated his attention on three aspects, viz.:

a. The suspect package found during underwater surveys by the port side of the bow ramp.
b. Damage near the visor starboard side locks.
c. Damage on the car deck at the port side forward.

After dealing with each item in turn, he has drawn certain conclusions.
These are:

a. The suspect package
It has been considered whether this suspect package could have been an explosive device even if the sides of the cube were no longer than 100 mm - the smallest estimate. A block of this size would indeed have enough space to hold all the essential components of a small explosive charge of one to two kilograms.
Finding such a device near the side locks suggests an attempt to damage the ship at a particularly vulnerable position. However, in later video surveys of the same area, the package has disappeared. When or how the device got there must remain a matter of conjecture. It can only be emphasised that the act of placing and arming such a charge takes only a few seconds as the firing time will have been set beforehand. A determined saboteur might well decide to increase his possibility of success by placing more charges, at similar vulnerable points elsewhere on the ship.
Brian Braidwood concludes that on a balance of probabilities the suspect package could have been an explosive device containing between one and three kilograms of plastic explosive.

b. Damage near the visor starboard side locks
Photos of the visor tank on land, show that on the starboard side, the two metal plates forming the hook for the manual side lock were severely distorted and folded onto an overlapping position. The lug for the hydraulic side lock has been ripped off the visor tearing away a flap of metal. The photos also show distinct darkening of the white paint surface above the badly distorted hook for the manual side lock. This marking looks like burn or scorch marks.
On the port side, however, the ends of the two metal plates forming the hook for the manual side lock had only been pressed together. Also, the lug of the hydraulic side lock had been ripped off where its welding has given way, but there was no sign of burn marks anywhere on the port side.
There are several black and white photos and one composite picture made up of overlapping video stills. This composite picture gives a dramatically clear impression of the damage to the ship's bulkhead in the area of the side locks. This view of the damaged area was taken from the forward side of the bulkhead looking aft. The bottom half of the picture shows the opening for the manual side-lock hooks. Above that is the hydraulic side-lock lug which was torn off the visor. Above that again is a fresh hole in the metal.
Dealing with the details from the bottom, the picture shows that the extreme lower end of the manual side-lock opening is still in the shape of a smooth curve and so is undamaged. However, within a very short distance, the metal has been splayed out towards the camera. This is easier to see in the actual video.
At the top of the opening for the manual side lock, photos show damage to the bulkhead in the immediate vicinity of the visor damage just described. In a colour photo, the opening designed to receive the hook of the manual side lock, has been enlarged by damage at its upper end and some pieces of metal may have been completely displaced from the area. The manual side-lock securing mechanism can been still inside the hole as it was never secured for the final voyage.
The hydraulic side-lock lug, which was ripped away from the visor, was lodged in its recess on the starboard front bulkhead where it would normally be located when locked. At the edges of the hole the metal seems to have split in all directions away from the centre. this is all characteristic of the sea of an explosion.
Just above this area there is a fresh hole which is made by a flap having been pushed back in an S-shaped fold. It is a fairly round hole about 250 mm across. Some of the metal has been pushed in, (away from the camera position).

A comparison with the port side bulkhead showed no damage at all that might have been compatible with an explosion.

The circumstances surrounding a possible explosion can be explained as follows: By midnight, the weather had deteriorated and because of an ineffective seal the visor space was filling up with sea water. By 0045 the level would have been well above the hydraulic side locks. This water would have been pouring through the openings for the side locks to flood the compartments adjacent to the car deck. It would also have been coming directly into the car deck past the ineffective bow ramp seal. At about this time a major crash was heard from the forward part of the car deck. There was certainly a lot of noise by this time and this may have masked the sound of a small explosion.
The marking and damage suggests that if an explosive device was used it would have been placed on the after side of the bulkhead, just above the manual side-lock slot. This means that a device like the one described earlier would have remained in place despite water flowing through the slot just below it. When it exploded, it was probably completely surrounded by water, with the other side of the bulkhead also flooded. This would have resulted in a strong shock wave through the water reaching the nearby visor. However, the presence of water on both sides of the bulkhead would have reduced the area of damage. The chock might well have fractured the welds of the hydraulic side-lock lug, which was retained in the bulkhead by its pin. The welds apparently tore out the triangular strip of metal seen on the photo of the visor.

To sum it up, the following damage has been described and illustrated in the area of the starboard side lock:

- Split and torn metal damaged around the top part of the manual side-lock opening front bulkhead.
- All of this damaged metal has been pushed forward towards the visor.
- Darkening of the visor paintwork at exactly the same level as the damaged metal described.
- The hydraulic side-lock hooks just below the burn marks were pushed down and severely distorted in a manner unlikely to have resulted from any mechanical impact.

On a balance of probabilities Brian Braidwood has concluded that:

- The damage near the starboard visor side locks was caused by an explosion.
- The charge weight was between one and two kilograms of TNT equivalent.
- The explosive device was placed on the forward bulkhead, just above the manual side-lock recess.
- The device could easily have been placed by someone following the route taken by the crewman responsible for operating the manual side lock.

c. Damage to the car deck port side forward
Brian Braidwood investigates damage in the port forward corner of the car deck, to establish if it might have been caused by an explosion. The damage can been seen in a short part of Video B40c which was taken by a diver. From the video it seems that the diver may not even have been aware of this particular damage, or else was told to look away and concentrate on other areas. The damage is only visible when the camera and light, which the diver is wearing on his head, are turned briefly to one side. There is no reference to the hole by either the diver or his supervisor. Nevertheless, the relevant section of the video has been studied in great detail to establish the possible cause of damage. The image is seen most clearly when the video is played in very slow motion, or even frame by frame, using specialist viewing equipment.
The videos and still photos from around the port forward corner of the car deck show a widespread presence of some sort of red or pink material. Some of it is very shiny and reflects the diver's light. The material may be bedding. In an case it seems to have been used to reduce the flow of water from the flooded visor space past the edge of the raised bow ramp and into the car deck.
Based on estimates from studying the video and still photos, the lower edge of the damage is about 300 mm above the deck level and there is no apparent damage to the deck itself. This suggest that the device may have been lying on something, perhaps bedding, when it exploded. It could, therefore, have been placed in a higher position and become dislodged by some physical impact in the immediate vicinity. The forward edge of the damage is about 300 mm away from the forward edge of the bulkhead.
Inside and around the hole can be seen the red and pink colouring of the bedding. It looks as if some of it was inside the adjacent compartment and can be seen through the damage hole. The damage hole itself is fairly round and about 300 mm across.
The hole is bordered by petals of split metal which have split in all directions away from the centre of the hole. The photos are taken looking at the bulkhead from inside the car deck space and it can be seen how the petals cast strong shadows onto the bulkhead. This clearly shows that the metal has been pushed away from the bulkhead into the car deck space.

The circumstances surrounding a possible explosion can be explained as follows: By midnight, the weather had deteriorated and because of an ineffective seal the visor space was filling up with sea water. By 0045 the level would have been well above the hydraulic side locks. This water would have been pouring through the openings for the side locks to flood the compartments adjacent to the car deck. It would also have been coming directly into the car deck past the ineffective bow ramp seal. At about this time a major crash was heard from the forward part of the car deck. There was certainly a lot of noise by this time and this may have masked the sound of a small explosion.
When the device exploded in the manual side-lock access compartment the space would have been flooded. This means the device would have been surrounded by water with air on the car deck side of the damaged bulkhead. However, from the comparatively small extent of damage, it is unlikely that any device exploded in contact with the bulkhead, and there is no way of knowing how far from the bulkhead it might have been.

In summary the following circumstances were established:

- A fairly round damage hole in the port bulkhead of the car deck adjacent to the bow ramp.
- Split and torn metal petals around the edge of the hole.
- All of the damaged metal pushed away from the bulkhead into the car deck space.
- That any explosive device used could have been dislodged from a higher position and fallen on some bedding in the compartment next to the car deck.
- Any device used would have been surrounded by water when it exploded. These points, taken together, suggest that a small explosion occurred on the far side of the bulkhead with the seat of the explosion being in the centre of the damage hole.

On a balance of probabilities, Brian Braidwood has concluded that:

- The damage in the car deck port side forward was caused by an explosion.
- The charge weight was between one and two kilograms of TNT equivalent.
- The explosive device was placed inside the space used to give access to the visor side locks.
- The device could easily have been placed by someone following the route taken by the crewman responsible for securing the manual side locks.
- The seat of the explosion was just above deck level as if the device had been resting on something, perhaps a pile of blankets, before it went off.
- The device may be have been placed on the forward bulkhead like the one on the starboard side, and been knocked off to fall onto some bedding before it exploded.

The complete Report is attached as Enclosure 34.7.435.

 

34.7.1
Supplementary Investigation Report
by Brian H.L. Braidwood, MBIM, MIExpE, Weymouth/UK

After the discovery of further unexplainable damage in way of the starboard front bulkhead of the wreck above and below B-deck, Brain Braidwood was requested to examine also these areas. His respective findings and conclusions are explained in the above mentioned report which is attached as Enclosure 34.7.1.435.1. As to the damage above B-deck level the expert has concluded on the balance of probabilities:

1. The condition of the port actuator was caused by damage when it ripped through the forward bulkhead on tearing away from its base plate.

2. The lack of damage to the starboard actuator means that the adjacent hole in the forward bulkhead must have existed before it passed through when it tore away from its base plate.

3. The hole in the starboard forward bulkhead was not caused by the starboard actuator.

4. The pattern of petals along the sides of the hole is characteristic of explosive damage.

5. The hole in the forward bulkhead was caused by an explosive device.

6. The damage to the bow ramp is indicative of an explosion.

7. The seat of the explosion was on the after side of the bulkhead.

8. It is possible that the damage above and below B-deck/upper car deck level was caused by the same explosive device.

 

As to the damage below B-deck the conclusion on the balance of probabilities are:

1. The hole in the longitudinal of the manual lock access space by the starboard side of the car deck was caused by an explosion.

2. The damage extending down the ship's forward bulkhead from the starboard side locks was caused by an explosion.

3. The damage to the starboard side of the bow ramp below the level of B-deck was caused by an explosion.

4. The damage to the lower part of the visor on the starboard side was caused by an explosion.