Jepp High Enroute Questions

[Alchemy]

I've got 2 quick questions about jepp high altitude enroute charts.

1. How does one navigate on an airway with a "temporary gap in navigational signal coverage". I see symbols for this (looks like a torn in half black recatangle) on Jet airways and am wondering how it works.

2. Where are the Center Frequencies listed on the chart? I couldn't seem to find any on the one I was looking at today except for a big list of them on the front cover of the chart, but that list doesn't mention which area each freq. covers. Are they somewhere on the chart itself or just on the front cover?

Say you're on a jet airway and you somehow lose track of what frequency you should be on, how do you know which center to try?

[E_Dawg]

1) you just fly the heading you were on while you don't have nav coverage.

[DE727UPS]

You could always come up on 121.5, state your position, and ask if someone could suggest a freq. I know that sounds overly agressive but since we've started monitoring guard freq. more, I've heard many non-emergency type trasmissions. I heard an Aloha flight the other day accidentally make a company ops call on 121.5. About three ATC facilities came on to mention to the guy he needed to flip the switch. Flying beyond the coverage of your assigned freq. could become an emergency in just the wrong circumstances, so I don't think it would be inappropriate to use 121.5 to get yourself back on track.