Lost comms in TAA

Technically there aren't any "fifteeners" in the Colorado Rockies, so 15 would clear all terrain. Not by a large margin in a few places, but it would clear all.

14 on the other hand... 60 things you could hit, some of which are more ridges than peaks.

https://en.m.wikipedia.org/wiki/List_of_Colorado_fourteeners

Having worked with obstacle clearance for many years the minimum safe random routing altitude over the Rockies would be 16,500, and that may be insufficient on a windy or very cold day.
 
Reading through this I learned a few things. (no! really!)

But I'm wondering what would actually happen in the plane. So your in a 172 with 2 nav/comm radios with CDIs, and a WAAS GPS. If you lose one comm radio, generally do you lose that nav radio as well? I understand this depends on the model of radio. What would cause just the comm to just die? Likely?

Or is a complete electrical failure more likely? In that cause you'd lose the GPS and all radios. Still have the 6 pack, except the electric T&B indicator in the 172. So, 5 pack.

What are your options?
 
Reading through this I learned a few things. (no! really!)

But I'm wondering what would actually happen in the plane. So your in a 172 with 2 nav/comm radios with CDIs, and a WAAS GPS. If you lose one comm radio, generally do you lose that nav radio as well? I understand this depends on the model of radio. What would cause just the comm to just die? Likely?

Or is a complete electrical failure more likely? In that cause you'd lose the GPS and all radios. Still have the 6 pack, except the electric T&B indicator in the 172. So, 5 pack.

What are your options?

Depends on the reason for the failure.
 
I lost my single NAV/COM today on the way back to the home drome. Both NAV and COM went belly up. I think it is a connection problem somewhere. I was VFR, but it was still a little nerve wracking as I have come to rely on the radio to help with traffic and we have a pretty good mix of light GA and Bizjets. Not a fun afternoon. :(
 
Reading through this I learned a few things. (no! really!)

But I'm wondering what would actually happen in the plane. So your in a 172 with 2 nav/comm radios with CDIs, and a WAAS GPS. If you lose one comm radio, generally do you lose that nav radio as well? I understand this depends on the model of radio. What would cause just the comm to just die? Likely?

Or is a complete electrical failure more likely? In that cause you'd lose the GPS and all radios. Still have the 6 pack, except the electric T&B indicator in the 172. So, 5 pack.

What are your options?

In the case of the airplane going completely dark and you can't fix it, you have few options.

Hopefully you have been monitoring the enroute weather and have a general idea of the ceilings and terrain below you.

-Descend to VFR and scud run to an airport.

-Climb on top if possible and find VFR or a hole to descend through.

Edited to add: If you have an ipad onboard or some other portable GPS, something that runs off it's own power source, then you could theoretically use that to get down. Might actually be a good scenario to use Foreflight SV to save your butt:D
 
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The most common electrical failure is probably lose the alternator which means you get a warning, and 1/2 hour later it goes dark. If its the battery you will notice dimming then failure. Just the Comm COULD fail and the Nav stay ok. That is POSSIBLE.
 
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