Posted by Scott McWilliam on November 10, 1999 at 16:14:17:
In Reply to: Ship Construction question posted by SooDiver on August 15, 1999 at 19:12:18:
Interesting question, in my experance wrecks deeper than 150 often have there masts up, there seemes to be a number of factors at play.
1. If the mast is near or passes through the air water interface Ice, wind and wave damage seem to end up talking the mast down. Also it should be remeebered that we are seeing ice scour marks down to 60 or 80 feet in the great lakes this would definetly take down a mast.
2. The strength in the mast that holds it up is in its standing rigging, (stays) and in early sailing ships more often than not we are talking hemp, this rots a way and all that is holding the mast up is the step and the deck.
3. Many masts have been knocked over by fish trawls when they are in this unrigged state.
4. The structural integrety of the vessel after wreck event clearly has a bearing on the probability the mast will remain upright.
5. I dive of eight wrecks that all have there masts up, and in eaach case the vessel has a post deposition high degree of structural integraty, and are in excess on 150 of water.
Just my observations, Scott
In all of the old wrecks I've dove the masts are missing (except the Sandusky). Is this because they are salvaged after sinking? Some would certainly stick up above the water (in some wrecks, due to the damage around the mast holes it looks like ice may have taken them out). For example on the Maitland in the Mackinac Straits, there is no sign of violence around the mast holes, as if they were just pulled out from above. Or are they not fastened at all and just rest in their step holes, floating out after sinking?
: thanks