Comm Fail

[Big Pistons Forever]

The good Colonel has started several very good threads aimed at lower time pilots. In that spirit i offer the following:

------- You can stop reading if you have more than 500 hrs TT------------------------------

So you are near the airport or in the circuit and it suddenly gets quiet, what to do.

Well the first and most important thing is

Continue To Fly The Airplane

This sounds rather obvious but it is very easy to get totally distracted by a problem and lose track of the basic like continuing to watch where you are going and minding heading and altitude.

When things go wrong at a busy time it is important to be systematic in your troubleshooting by going from most likely to least likely.

This is the order I teach when dealing with a suspected comm fail

1) Check the volume. The most likely reason you can't hear anything is because you inadvertently bumped the volume down. The best way to set/check radio receive volumes is to turn off the squelch (Not this is often called the "test" position on older radios. With the squelch off you should hear the radio hissing. If there is no hissing turn up the volume and you will probably have identified your problem. If there is no noise at max volume check to see if the radio has a stuck mike. On newer radios with electronic displays radios there will be a "t" or "tx" illuminated when the radio is transmitting. Obviously if the tx light is on and you are not pushing the PTT switch you have found your problem. Turn off the radio and give the PTT switch as good punch.

2) The other common pilot induced comm failure mode is either a mis selected frequency or a mis set audio panel. Of note those horrible Cessna audio panels have a "gotcha switch". It is the first togel switch in the line of switches and selects phone or speaker for the entire panel but also has a centre off position which will kill the audio.

3) If the above doesn't work and you have a second radio then you should try that one.

4) If none of the above work sqawk 7600 and fit yourself into the circuit in a logical way. If you are at a controlled airport you will get a green light on final every time.

Unexpectedly loosing your radio blankee can be a bit disconcerting for a new pilot but it is not an emergency if you pay attention to flying the aircraft and are able to quickly and methodically troubleshoot the problem.

Hope the above has been some use to the readers of Avcanada.

[Tail-Chaser]

Having the Tower/FSS number on your phone isn't a bad idea either.

[Cap'n Tripps]

In the spirit of completeness, you might want to check your headset is still plugged in as well as all of the above, especially, if you can hear them, but they don't seem to hear you.

Cheers!

[Rookie50]

Good thread. Especially if IFR really consider a good handheld radio as well.

[Krimson]

The tower/FSS will likely have an emergency line in the CFS. Make sure you have one along with you.

With a lot of headsets being able to pair to your cell phone with bluetooth, call up tower, tell them what happened, your ETA and how you will join the circuit. It makes it your moves very predictable and they will have you accommodated already.

That's what worked for me, and I carried a handheld backup until I was able to replace the defective radio.

[Shiny Side Up]

Beat me to the punch BPF, good thread. Mine would have been more ranty and less educational. But in the spirit...

Of note those horrible Cessna audio panels have a "gotcha switch". It is the first togel switch in the line of switches and selects phone or speaker for the entire panel but also has a centre off position which will kill the audio.

Note that the switch BPF is referring to is the "AUTO" one in the picture. This is probably the most common source of comm trouble with most PPL holders. On that note a second common error is the use of the controls for the marker beacon to use the radio. Some similar comm panels have a volume knob for said system which is going to do nothing to alleviate your comm difficulties. This goes to the priniple if you don't know what a switch does, ask about it before you start playing with it.

Here's a few other common sources of comm "trouble".

5) Nav/comm trouble. Frequently pilots will complain that the problem isn't that they don't have a functioning radio but rather that they can't hear what's comming through it. Frequently this is because every volume knob in the airplane is turned up so there is a deluge of static from a bunch of dead frequencies comming through their headset. Check to make sure any ADFs, and VORs volume is turned down if they are not in use, and especially if you can't currently recieve anything on them.

6) Intercomm trouble. Pilots also tend to panic if they can't hear themselves talk to themselves and assume they have a comm failure. Remember that the radio and the intercomm are two different systems.

7) It might not be you. Pilots also tend to assume that it is their own radio that has failed instead of someone else's, especially when they get bad transmissions. If you can't hear someone very well, there is a strong possiblity that the problem is on their end. Lots of guys out there with cheap radio sets, and I know of far too many guys who fly strictly with a hand held (and lots of those in very noisy cockpits). This is more an uncontrolled airspace problem than a controlled one, but I have been there when ATC's transmitter has had a problem too. Use some deductive reasoning. If you heard one person clear, and someone else not, its probably not you. Also, if you're really worried its you, try another frequency - this solved the controlled problem the one time, not my radio with the problem.

Uncontrolled airspace can be quiet. For some reason radio silence is a terror to many pilots. I've learned to enjoy that small pleasure, but many don't. Either way, you'll occasionally hear that pilot making those panicked radio check calls on 126.7 or on the local Aerodrome frequency.

[Scout44]

Another important consideration of a comm failure is thinking of your actions should you experience the failure at night and require use of ARCAL at destination. Is there an alternate within reach with a lit runway like a CZ or MF? Do you have a handheld? Etc, etc.

[Cessna driver]

I have talked to the controllers at my local airport and they would rather us call them on a cell phone prior to squawking 7600. They said it can be a distraction for them on the radar with a flashing blip when they get busy.

[Big Pistons Forever]

I have talked to the controllers at my local airport and they would rather us call them on a cell phone prior to squawking 7600. They said it can be a distraction for them on the radar with a flashing blip when they get busy.

Not a bad idea if you are outside the zone and want to get in. IMO if you are already in the zone you should not be fussing with the phone, just dial up 7600 and follow what ever your last instruction was, join the circuit in the most logical way and then land.

[jump154]

Great Post. I have a story to tell.... The moral is

1) I agree with BPF
2) I agree with The Colonel, re know your systems inside out.

Last fall I was doing my night rating, needed the last hour of solo which was a planned short cross country to a controlled airfield. Was in a newer aircraft (172) in the school fleet that I loved flying, but did not have that much time in.

All went well, entered the zone, cleared to join Base, got clearance for a touch and go. On base, as I lowered final flap heard increased static through headset (something keyed in the squelch). Easy fix, I did what I had done many times before and pushed the dial on the intercom panel that resets the intercom squelch. Static went away, along with everything else including my intercom.

Quick check of everything else, all electrics working fine, all gauges green. So at that point I though I had lost the radio, so what to do? I already had T&G clearance, so decided to proceed with that and return to my home field (15 mins away) rather than do a full stop and be on a controlled airport with no com. Set squawk to 7600, performed T&G.

On climbout, my thumb knocked the PTT switch and I heard a burst of noise, and the T indicator lit up. A quick transmission, and I realised I still had com. Spoke to tower, reset squawk and all OK. Got home, landed, reported the snag. Instructor came out, checked the panel, all worked OK.

So what did I do wrong?

- I didn't know my systems fully. Completely forgot that when I lost Intercom they have a fail safe mode and Com 1 still works even without power. I lost Intercom, never lost com.

- I didn't know my systems fully. This aircraft has a slightly different model of audio panel than I was used to. There is no dial with a push to reset squelch. There is a push on/off button. Yes, I turned a perfectly functional intercom off. Did nto realise that until half way home in the car.

- Fly the Aircraft! Other lesson, with the increased workload of climbing out and talking to tower, my right turn out (pre cleared by tower) was more of a 180 degree turn out. Lucky it was night and quiet, quickly identified and corrected quickly - but could have been something more critical I missed.