But when gunners requested permission to open fire, they were firmly refused. In part, this was because the submarine's location remained uncertain because of difficulties evaluating reports from different observation points; it was, after all, from shore. Furthermore, authorities later stated they wished to avoid revealing the locations of their guns to what they believed to be a reconnaissance mission. The sub may also have been out of range of Battery Russell's artillery; the mechanism used with the 10-inch disappearing guns limited their upward travel, which limited their effective range to less than . If the guns opened fire, the sub would be able to report back to Tokyo that a fleet of surface ships could simply heave to, from shore, and pound Battery Russell with impunity, then sail right on into the Columbia—where, among other valuable targets, upstream at Portland, Oregon Shipbuilding Corporation, one of Henry Kaiser's shipyards, was cranking out Liberty ships at a rate of more than one a week. This, obviously, was not something the Navy could take a chance on.