DES NOW in CLB Mode (747-400)
Has anyone tried the DES NOW feature while still in CLB mode on the B744? The Bulfer book says it will delete all climb and cruise constraints, but it does not state whether it will force it out of CLB and into DES. Others have claimed it will not work at all while in the CLB mode, even though the DES NOW prompt is visible on the DES page while in CLB.
The reason for asking is to see if this would be a another option for getting out of CLB mode for a return to departure airport, prior to reaching your cruise altitude or, on a missed approach, prior to reaching the higher of your MCP altitude or the missed approach altitude. Of course, once you reach this altitude it will go to CRZ automatically and then transition to DES after crossing the T/D boundary.
I am aware that the option of using a non-VNAV mode (FLCH, VS) to descend while in CLB mode would be an alternative and probably preferred method, but I'm interested in whether DES NOW would force it into DES while still in CLB. Thanks.