That is disappointing for a couple of reasons: What is it then? If from the NC, then the theory about the wreckage all being 'down stream' could be wrong. Those items are 'up stream'.
Disappointing??? How so? The anomaly is way too far north to be NC wreckage. That's very, very good. We know where the stern of NC went. We found it at about 1,000 ft depth directly behind the shipwreck. It's not surprising that tons of ship structure tumbling down the reef slope were apparently not effected by the current.
The anomaly is several hundred meters "upstream" and shallower (600 ft).
If the Lectra was beaten up bad enough to open it's guts, maybe one or two of the tanks came out. They would try to float....somewhat....and they would not apear as A/C wreckage either.
True. I fully expect that the underside of the aircraft was ripped open when the plane was pushed along the reef surface on it's belly before going over the edge. That why it sank so fast. The fuel drains for the fuselage tanks were on the belly. If they're ripped open the tanks, which were vented on the top, will quickly fill.
Also, think about the airplane parts found by TIGHAR or said to have been seen by PBY pilot John Mims in the village. Sheet aluminum, control cables, heat shields that (we theorize) were once nailed to the wooden floor, plexiglas from a cabin window - if that stuff is from the Electra, the fuselage was breached before the airplane sank into the depths. The fuselage of that airplane was not an empty shell with some fuel tanks. It was packed with cables, wires, pipes, conduit, gear motor, flap motor, actuating tubes, spare parts, tools, Fred's navigation station, etc. A sinking fuselage with it's belly ripped out would likely be trailing its intestines like a whale gutted by sharks. None of the guts, including crushed fuel tanks, would necessarily look like airplane wreckage. They might just show up as a trail of small targets strung out behind the fuselage with only the bigger chunks throwing a low shadow.