Lots of interesting discussion on this thread. So, why did the Algoma Verity, with a pilot with years of experience on that waterway at the conn, run aground?
Per the NTSB report, the usual suspects can be excluded: drug and alcohol tests were negative, the pilot wasn’t on his cell phone, and, at least as reported by the pilot, he had plenty of rest prior to the incident. There were no material deficiencies with propulsion or steering. There’s no indication that the crew failed to follow the pilot’s orders.
A lot of discussion in this thread about the “channel.” The ship was outside the marked (dredged) channel, and, as a commenter noted, pilots may use navigable waters outside of the marked channel if the situation demands it (OBTW, when I was captain, you can bet I was checking with the pilot about it). But, if a pilot is going to go outside the marked channel, he better be damn sure of the limits of those navigable waters (it’s one of the reasons we have the pilots in the first place, is it not?). The Algoma Verity hit bottom exactly where the Corps of Engineers survey data showed that the water depth shallowed significantly. The pilot had access to the COE data.
Also some discussion about the rudder being perhaps too small or not effective. Doing a quick check of the AIS history, it looks to me like the Algoma Verity had been up and down the Delaware River quite a few times. If the ship was a problem, I’m sure the DelPilots would have raised the issue on an earlier voyage. The pilot who conned the ship earlier in the voyage told the accident pilot that he would have “no problem” getting the ship up the river. Algoma Verity was not a great handling ship, apparently, but I’m just not buying the argument that the cause of the accident was a ship that was too squirrely for the waterway.
So, I can’t see a reason for the grounding, other than the pilot drove the ship onto the shoal. Why? It doesn’t seem like the pilot offered up any clear explanation himself. But what he did say was that he expected the ship to be set to port, and he expected the bow to dive to port. He drove the ship accordingly (take a look at the timeline in the appendix of the NTSB report, btw). The ship didn’t get set to port, though, and the bow didn’t dive to port. In fact, the ship continued to go to starboard until it reached the limit of navigable waters. So, the pilot expected the ship to do something, it didn’t do what was expected, yet the pilot continued to take action based on his expectations. That sounds a lot like…expectation bias. The NTSB’s conclusion seems as good as any (and note the NTSB hedged a bit, stating it was “likely” expectation bias).
Expectation bias is a real phenomenon (and it is not merely having expectations—it is letting those expectations override the perception of what is really happening). Lots of research on this, and it is not just an aviation thing. I suspect aviators take this a lot more seriously, though, given the severe consequences when mistakes happen.