This past weekend we chartered a fishing boat to take us out on Lake Erie to the location where we last saw Project Mustard Seed in November to try and determine what caused the failure. We used the same side-scan sonar imagers that fishermen use to scan the bottom of the lake, as well as a USB underwater camera system we designed to take detailed pictures and video. While the camera worked successfully (despite springing a leak), sadly, there was no hardware to be seen or found.
We have gone over the most credible failure modes which could have led to the rig being lost. Our expectations and hopes were that any hardware found would give us a clear indication of the most likely failure scenario.
For example, we thought that if the core cans (the ones in the center of the rig) were found intact at the bottom of the lake, still attached to the anchor line, it would indicate the rig had broke apart because the set-screw structure failed. Since the center was not sufficiently buoyant without the parameter cans, the core would have quickly sink without the tubes connecting it to the parameter. Tube structure failure seems a likely scenario due to the 22′ waves the rig experienced!
So, without any hardware or evidence, we can only conclude that Lady Bessie has won this round. We have now brought Project Mustard Seed – the world’s first freshwater windfarm – to a close. Please check back for more information about the next big project that Operation Mustard Seed has planned.