Markoz wrote on Jul 12^th, 2012 at 7:09am:

boeing247 wrote on Jul 11th, 2012 at 11:57pm: Oh, haha--looks like they weren't. However, does an inop pitot result in no speed display on the Ctrl+Z menu? It happened to me too, but in the Catalina between Australia and New Zealand! The SHIFT+Z displays KIAS. The 707's Indicated airspeed disappears when the pitot tubes freeze, and so it also disappears on the SHIFT+Z display. ;)

Ah--I didn't realize that the Shift+Z KIAS are actually linked to the gauge (i.e. that they didn't function as a separate, more precise gauge like the altitude indication).