Lost comms scenario

taseal

Well-Known Member
I just got out of bed for this.... it was one of those 'i'm not so tired so i'll think scenarios' moments lol

lets say you have a flight from KMIA to KATL in a king air...

u depart KMIA and around KPBI (like 25 mins) you lose comms....


altitude you're fine, route you're fine. its pure IMC outside so u can't go VFR and land somewhere...

now the regs say to go to a apporoach fix and hold until EFC/ETA then land.

a flight form KMIA to KATL would be like a 3 hour flight almost. when you lost comms, u still have about 2.5 hours til ETA....

what are ya gonna do? hold at some app fix by PBI for 2.5 hours???

continue to KATL with both radios lost (and not knowing what else can go wrong with the electrial system next) and do the hold over IAF until ETA and all?
 
In IMC? Continue to KATL and hold at the IAF until ETA, then shoot the approach. And squawk 7600 of course.

Im 98% sure this is what the FAR/AIM says to do when you lose comms, correct me if im wrong. I wouldnt want to divert to a differant airport/route unless it was absolulty necessary.

If you continue with your route using normal lost comm procedures atleast ATC knows what your doing and can move other aircraft out of your way. If you start diverting on your own they have no way of knowing what your intentions are.
 
yes thats what it says, thats why I asked...

thats helluva flight with no radios. like I said, it could be an electrical problem, and u might be loosing other things maybe.

would u really wanna fly for 3 hours with no comms?
 
I certainly wouldn't want to.. but that's what you're supposed to do and if it's IMC the whole way, its pretty much you're only and smartest choice...
 
If everything was working ok besides the comms then yes I continue, even on a long flight like that.


If for some reason I think I might lose everything electrical then and only then might I be trying to find a way to land somewhere nearby. Im not sure what the procedures are for diverting without comms though. Why would I be thinking that just because radios fail that I might lose everything? Usually this is something you would know is going to happen, IE you get an alternator warning light and your loadmeter is showing 0 (in a Piper Seminole). If your not getting an alternator light and your loadmeter is reading normal, you have no reason to think you may be losing your entire electrical system.
 
I guess this is a 135/121 question, but would u make an announcement about this? I guess there is no need if u are going to ur planned place of landing.
 
That would be a LONG way without hitting some VMC along the way. Hopefully you did your hw with the WX and you know where you might breakout. Otherwise you just cruise 3 hours to ATL and shoot the approach as close to your ETA as possible.
 
Basicly, that's true, however, having Atlanta as a destination poses another 'PIC decision'. You may not be comfortable (read 'feel unsafe') with going into a high-density airport like ATL with no comm, so a diversion to a low density non-towered airport along the way that has a good instrument approach that you feel will pose a less threat to safety, might be a better idea. 91.3(b) PIC emergency authority.
 
Basicly, that's true, however, having Atlanta as a destination poses another 'PIC decision'. You may not be comfortable (read 'feel unsafe') with going into a high-density airport like ATL with no comm, so a diversion to a low density non-towered airport along the way that has a good instrument approach that you feel will pose a less threat to safety, might be a better idea. 91.3(b) PIC emergency authority.

I would not feel safe diverting in IMC with no comms. This would be a last resort for me.

If you squawk 7600, ATC knows you have lost comms and expects you to follow standard lost comm procedures. As long as you follow them they know what to expect and can clear traffic for you. Even if Atlanta is high density, they have your ETA and will clear your approach path. Remember, just because you lose comms does not mean you lose radar contact with ATC.

The minute you start diverting or going against procedures ATC does not know what your doing.

Atlanta is a long flight but as one of the posters above said, hopefully you should break out somewhere along the way and then you can just decide what you want to do in VFR conditions.
 
I just got out of bed for this.... it was one of those 'i'm not so tired so i'll think scenarios' moments lol

lets say you have a flight from KMIA to KATL in a king air...

u depart KMIA and around KPBI (like 25 mins) you lose comms....


altitude you're fine, route you're fine. its pure IMC outside so u can't go VFR and land somewhere...

now the regs say to go to a apporoach fix and hold until EFC/ETA then land.

a flight form KMIA to KATL would be like a 3 hour flight almost. when you lost comms, u still have about 2.5 hours til ETA....

what are ya gonna do? hold at some app fix by PBI for 2.5 hours???

continue to KATL with both radios lost (and not knowing what else can go wrong with the electrial system next) and do the hold over IAF until ETA and all?

Pull the power back to save fuel while you fly to the fix so you'll hit the fix at the same time your at your ETA. Then by slowing down, maybe the wx will change in route, and ou have to trouble shoot more, and if you pull back to max econonmy cruise you might save the company some cash.
 
There is no reason to divert unless you hit VFR. I think it would be kinda nice, not having to bother with checking in every handoff.
 
Pull the power back to save fuel while you fly to the fix so you'll hit the fix at the same time your at your ETA. Then by slowing down, maybe the wx will change in route, and ou have to trouble shoot more, and if you pull back to max econonmy cruise you might save the company some cash.

Uh would it cause the controllers and issue if you're outside your flightplan speed tolerences? In a light airplane, you aren't talking too significant of a gap. Larger and heavier planes, you might be looking at 20 or 30 kts.

In this situation, you have alot of fixes to pass. Chances are you've flight planned your ETA to those fixes, so worry about that. If you do your part, the FAA will do theirs.

I've never had this happen before, but if/when I do, I'll have the TAS nailed and expect to cross altitudes/speeds nailed (should there be any), and land on my planned runway.

My $.02
 
There is a standard procedure when losing coms and it goes like this.

If your in VFR conditions you land at the nearest practibable airport.

If your in IFR you do as follows...

For your route: Use AVEF

Assigned
Vectored
Expected
Filed

In that order...

For your altitudes you use MEA

Minimum Enroute Altitude
Expected
Assigned

You fly the highest of the three at all times.

If your clearance limit is to an initial approach fix, then you fly to that fix and hold until your EFC time or your ETA if you do not have an EFC time, then shoot the approach.

If your clearance limit is not to an initial approach fix, you fly to your clearance limit and hold until your EFC or ETA if you dont have one, then fly to an initial approach fix and shoot the approach.

Im pretty sure this is correct, if im wrong someone correct me.

If you follow these steps in when in IMC with lost comms, ATC will do their part and keep traffic out of your way. If you start diverting for no reason they dont know what your doing and thats how people die.
 
Well said 3enginejock.

99.9% of the time, in your initial clearance, you are cleared to the airport. That said, you shouldn't have to hold anywhere. Thats assuming your clearance did not change after departing the origin. Why not just fly to the IAF of the approach selected at the airport, shoot the approach, and land?
 
Well said 3enginejock.

99.9% of the time, in your initial clearance, you are cleared to the airport. That said, you shouldn't have to hold anywhere. Thats assuming your clearance did not change after departing the origin. Why not just fly to the IAF of the approach selected at the airport, shoot the approach, and land?

I dont know, its in the FAR/AIM. You hold until your EFC time or ETA if you dont have one.

I think in lost comms I would hold till my EFC mainly to make sure the approach and runway is clear for me. If you just shoot the approach when you get there it may or may not be clear and I wouldnt want to take that chance.

Someone with more experiance or knowledge in lost comm situations wanna share?
 
I dont know, its in the FAR/AIM. You hold until your EFC time or ETA if you dont have one.

I think in lost comms I would hold till my EFC mainly to make sure the approach and runway is clear for me. If you just shoot the approach when you get there it may or may not be clear and I wouldnt want to take that chance.

Someone with more experiance or knowledge in lost comm situations wanna share?

Why would things not be out of your way when you get there? Can they not see you coming? Is there no radar?
You have to think when these reg's were written.
 
Like I said I dont know, im not experianced enough to say, im just quoting you what I learned during instrument training. And thats exactly what it says to do.

There must be some reason they put that in the regs.
 
Why would things not be out of your way when you get there? Can they not see you coming? Is there no radar?
You have to think when these reg's were written.

Call them on your cell phone. Then get clearance to shoot an approach. Better yet, call them on the cell 2.4 hrs ago before you trapsied halfway across the country. Then get approval to shoot an approach back into the home base.
 
Your cell phone usually does not work when your flying around 5-10k + feet. Imagine an airliner at FL350...your cell phone will not work and you are not allowed to descend per lost com regs, when in IMC of course.

My cell never works in the airplane, ive tried it when I was only at 5000 and it still didnt work. Usually I cruise at around 10000-12000 on my IFR cross countries. Cell wont work there and again you arent allowed to descend when im IMC per regs.
 
Your cell phone usually does not work when your flying around 5-10k + feet. Imagine an airliner at FL350...your cell phone will not work and you are not allowed to descend per lost com regs, when in IMC of course.

My cell never works in the airplane, ive tried it when I was only at 5000 and it still didnt work. Usually I cruise at around 10000-12000 on my IFR cross countries. Cell wont work there and again you arent allowed to descend when im IMC per regs.

I don't know where you were flying, but I usually get the best reception ever in the airplane. Tried it both in Wyoming at 5500 (1500 AGL) and in Los Angeles at 5500 (5000 AGL).

As a rough guide, based on a tall mast and flat terrain, it is possible to [transmit and receive] between 50 to 70 km (30-45 miles). When the terrain is hilly, the maximum distance can vary from as little as 5 kilometres (3.1 mi) to 8 kilometres (5.0 mi).

Source - Wikipedia
 
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