Difference between revisions of "Diving the Cape Peninsula and False Bay/MV Rockeater"
Revision as of 11:04, 4 May 2011
The Rockeater is a relatively bulky wreck for its length compared with the frigates Good Hope and Transvaal, and is quite a bit larger than the fishing boats Orotava and Princess Elizabeth. It extends further off the bottom, and provides a larger depth range at present than the others.
The MV Rockeater is the southernmost of the 5 wrecks in Smitswinkel Bay.
This site is in a Marine Protected Area (2004). A permit is required.
The "MV Rockeater" was built in New Orleans in 1945 as a coastal freighter for the United States navy. The ship was bought by Ocean Science and Engineering (South Africa) in 1964 to be used for marine prospecting. The ship could be positioned with an accuracy of 8 metres using on-board instrumentation and shore based transponders, and could be held in place by four anchors or positioned dynamically by using the twin propellers and thrusters.
Seabed surveys were carried out using acoustic reflection profiling to map sands and gravels over the bedrock, and an airlift could be used to suck up bottom sediments for sorting and grading. The Rockeater was also equipped with a drilling derrick to take core samples. This was cut off before the ship was scuttled and lies next to the wreck on the starboard side. After twenty years of this work the Rockeater was in poor condition and no longer seaworthy. It was planned to use the ship as a naval target, but because of fears that she might sink at her moorings in Simon’s town, it was decided to donate her to the False Bay Conservation Society. The Rockeater was towed to Smitswinkel Bay on 15th December 1972 and scuttled.
Sand bottom is at about 34m away from the wreck, and the depth alongside varies a bit. The scour pit at the rudder is quite shallow, the bottom is at about 34.7m at high tide, while further forward it is about 33m. The main deck is at about 32m, and the top of the superstructure, which is the shallowest part of the wreck, at about 26m.
Visibility is variable, and may be quite poor at times. On a good day it may exceed 10m, but even then it may be dark due to poor visibility in the surface waters. On a really good day visibility can exceed 15m all the way to the surface, but this does not happen often.
The wreck The structure of Rockeater is basically intact as far as framing goes. Hull plating is still more or less intact, but superstructure plating is heavily wasted and there are big gaps between most frames. There are many openings in the deck and superstructure.
The wreck lies upright on flat sand at about 34m, with bows to the west. The drilling derrick lies on the sand to the north west of the superstructure, and the helicopter pad has collapsed to port. The rest of the vessel is largely intact but has lost a lot of superstructure plating. The hull lies on the bottom buried to what looks like near the working waterline. Most of the rudder is buried in the sand and it appears to be bent to port, so it is possible that the lower sides of the hull have collapsed in much the same way as on the PMB. Otherwise as the draught is reported as 5.5m, the hull must have sunk at least 4m into the sand, which seems improbable. There is not much of a scour pit at the rudder.
There are a large number of openings into the wreck. On the waist deck there is a big rectangular hole in the deck plating and a number of smaller hatchways with raised coamings. There are several doors into the superstructure, and large areas of superstructure sides where the plating has wasted away almost completely,leaving only frames, which must be getting unstable and will no doubt collapse during a storm some time.
There is a lot of obscure structure on the deck, which was probably part of the drilling equipment, most of which has been removed or has collapsed. In good visibility the appearance should be quite impressive.
The site is exposed to swell from the south east, and to a certain extent, from the south west. Longer period swell will make conditions on the wrecks uncomfortable or hazardous due to strong surge, but short period waves will just make it uncomfortable on the boat. Visibility is less predictable, and at this time is largely a matter of luck and reports from divers who were in the area recently.
The site is usually at its best in winter but there are also occasional opportunities at other times of the year, though least often in summer, when the south east wind tends to blow much of the time.
This site is only accessible by boat. Launches are usually from the slipway at Miller's Point.
The wreck is too deep for much seaweed, but it is heavily encrusted with invertebrates, some of which are seldom seen anywhere else but the Smits wrecks.
Recent wreck of a medium sided steel vessel in fairly intact condititon.
If you have good visibility and lighting, there are opportunities for some good wide angle shots, and there are enough macro subjects of various sizes to keep the critter hunters happy. Due to the depth, use of powerful strobes set well away from the camera are recommended for all medium to wide angle work. unless you are happy to settle for monochromes in green.
No particular route is recommended. The wreck is small enough to visit quite extensively on a single dive, but there is enough to see to make it worth returning. Limited but challenging penetrations have been reported.
The Rockeater is the final waypoint of the Smits Swim, a dive tour taking in all five of the Smits wrecks on a single dive, and though you dont get to stay long on any of the others, if your air supply allows, there may be time to look around the Rockeater a bit before ascent.
The structure has lost a great deal of strength due to corrosion, and it may be unstable. It will most likely collapse during bad weather, but should be considered a risk in a strong surge. Scorpion fish have been seen on the wrecks, and are well camouflaged. Their spines carry a dangerous venom.
Certification appropriate to the depth is expected. Some level of training or experience in wreck diving is recommended, and penetration should only be attempted by suitably competent divers after reconnaisance and appropriate planning.
Equipment appropriate for the depth should be used. Nitrox is recommended for those competent to use it. A light is strongly recommended, and penetration should not be attempted without the appropriate equipment and planning. If you are not entirely certain what this would be, you are not competent to do the penetration.