Other factors could include the paint scheme. Lighter colours on the upper portion of the boat are more likely to reflect enough light back to allow the boat to be seen, presuming plenty of water under the keel. Against a light bottom you\'d want light colour upperworks. A very effective method of aerial camouflage turns out to be putting lights on the bottom of the plane and regulating them to the same luminescence level as the sky above the plane.

60 feet is just a little over 18 metres, which isn\'t very deep considering that depth is normally measured at the keel and not at the uppermost point on the boat. In the Pacific, US subs at 60 feet could put up their periscope and take a look around. So at 60 feet in a VIIC, it looks as if the pilot would really only have to be looking through about 30-40 feet of water. On an overcast day, with relatively clear water and a light, relatively shallow bottom, it probably wouldn\'t be that hard to see something. Polarized sunglasses would help a lot, too.

In the Pacific, the sudden arrival of depth charges got even more interesting after that brilliant congressman decided to reassure his constituents that their sons/husbands weren\'t really in all that much danger, since the Japanese were setting their charges too shallow. (Never presume that: politicians always think before opening their mouths; reporters will be able to recognise information that will help the enemy and refrain from printing it; and, of course, that the enemy doesn\'t read your newspapers.)

JTM