Solo Flight Radio Fault

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Renesh Kumaresan

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I was on a solo flight today. Just out to a practice area and back. My airport is class Delta, not that busy. Everything was going fine, after half hour I decided head back from the practice area to the airport for some touch and goes. Got the ATIS information code, and announced my position as normal. Didn’t hear a reply at all. Turned away from the airspace. Tried to listen to the ATIS frequency again and I couldn’t. Intercom was still working, since I could hear myself. I got worried. I even tried to contact the practice area, but didn’t work so squawked 7600. I had my phone, and Ads b traffic. So I stayed out of the airspace and watched for other traffic visually and on my iPad. The aircraft is a Cessna 172P. I called instructor, phone service disconnected just as he was about to tell me what to do. In the end he got atc to call me and cleared me to the land. It turned out that I was transmitting just not receiving. A switch on the com panel was left in the auto position which was supposed to be down. Never knew about this, I know I didn’t touch it, because I didn’t know what it is.

After that long story, all I have to ask is did I do anything wrong. I tried to wait for light gun signals but didn’t want to risk entering airspace. And does anyone know why the radio worked the whole time, but stopped just at the end with the phone/speaker switch in the auto position?
Thanks
 
Can’t tell you why it stopped as I wasn’t there to see what actually happened, but it sounds like a common rookie mistake to me. Don’t sweat it, it happens to all of us!
 
Radios aren’t suppose to do that on solo training flights? ... I’ve managed to turn dials, push buttons, forget about the fine tune... it happens. You learn
 
Sounds like one of them thar larhnin lezzons to me.

Betcha there's one more item on your checklist from now on.
 
AggieMike88 said:
Sounds like one of them thar larhnin lezzons to me.

Betcha there's one more item on your checklist from now on.
Click to expand...
Yeah, definitely. My instructor told me it should always be down, I’m gonna research more functions of the actual radio unit in the aircraft.
 
But was there anything wrong with squawking 7600? I told them I was a student pilot when I departed the field, and wanted to make sure they knew that I could not hear anything.
 
Most people won't even remember the squawk code for lost-comm. You did exactly the right things. These things will happen if you fly long enough, and the lesson here is not only how to prevent these from happening, but how you deal with it. Keep up the good work.
 
You didn't do anything wrong; maybe overeacted a bit, but no harm done. If something has to break (or not work as you expect), the comm radio is about the least important thing in the panel, unless the panel happens to contain an ADF. . .even with the radio out, the airplane still works fine and doesn't know if your're talking to anyone, or not.
 
A squawk is just another form of communication at your disposal, a tool you can use when you need it.
You did fine. *Breeeeeaathe!* :)

Audio panels can be a mystery wrapped in an enigma...
 
Until you mentioned that switch your problem sounded a lot like you turned down the radio volume to hear ATIS, etc on another comm radio. I have done this a couple times and feel dumb afterwards.

I just heard it happen to a pilot on FF last week. I think approach tried calling him 6 or 7 times before he figured it out and apologized several times. He could xmit just fine, everyone could hear him but he couldn't hear back.
 
Yea that’s what happened. I couldn’t receive. I was in an open class d so it wasn’t an issue to other traffic as I didn’t enter the airspace at all and stayed in one location.
Thanks everyone for all the replies, I feel much more relieved now understanding that the plane still was ok and I just had to wait to get the phone call. Only 17, so have overactive nerves. Definitely some valuable experience.
 
My first training flight in a helicopter we had a generator failure and had to come back in on the light gun signals.
 
I've got time in a couple of old 172 trainers that had really crappy audio panels and intercoms. They didn't work per the POH. And, each one had its own unique discrepancy. You had to learn what worked and what didn't. And, then just not change anything.
 
@Renesh Kumaresan - the trick I learned here on POA during my Private Pilot training was to leave my hand on the volume knob when I am temporarily turning it down. I think thanks goes to @denverpilot for that one! No problems ever since. This also comes in quite handy when on flight following and you are trying to listen to the second COMM to pick up ATIS at your destination. If you hear your call sign you can quickly turn up the primary COM again and listen to ATIS a few second later.

We had some space left over on our homebrew checklist fold out card. So one of the things I added was troubleshooting lost comms. It starts with volumes, then frequencies and audio panel positions and finally what to do (xpdr, etc) if nothing else works. We also have a handheld and in your scenario, if you were close enough they would have heard you (but they were anyway). More importantly you would have heard them to close the loop until you landed.

The guy in the example from last week was under the Bravo on Flight Following so I am think the controller trying to call him so aggressively was not worried that he had crashed...he was on radar. But rather to help keep him from getting a pilot deviation or wanting to bring him a bit lower for arrivals to our Bravo airport.
 
Get with your instructor to really learn the audio panel, and what each knob, switch and setting really does... not memorize a position (leave it down) without understanding the What and the Why behind it.

But, good job! Sounds like you handled it well!
 
But you could hear them fine before you took off ?

Good for remembering to squak 7600 though.
My instructor made me do a simulated comm failure when i had about 30 hours. Colored code light from the tower was actually fun to try and figure out and land to. The school I trained at 31 years ago is no longer in business, but when I went there they had three instructors, two guys and a gal. She was the toughest on me, so I tried to book mostly with her, one of the guys was okay as well, the other guy was completely useless as an instructor, flew with him twice, and never learned a thing. Sounds like your instructor is getting some good points across, even if you did bump a switch...stuff happens, and they are just good lessons if nobody gets hurt.
 
You did great. Don’t sweat it. Go up with CFI and touch every single button and play with that panel. You’ll laugh about this someday.
We’ve all done bonehead things in the cockpit learning. Lots of things.
 
A learning experience. Now you know something to bone up on. Something simolar happened to me on one of my solo XC flights, so I got to learn light signals. No harm, no foul. You are learning.
 
Normally radio failures are due to the pilot. Tell your CFI he needs to make sure you understand the audio panel before he signs his students off for solo.
 
You flew from a class D airport - How did you communicate to ground and tower prior to take off if that mystery switch was in the wrong spot? Did you inadvertently move the switch while in flight?
 
You may want to invest in a handheld VHF radio, especially if the planes you fly have these sorts of idiosyncrasies.
 
Something just doesn't sound (no pun intended) correct. You were able to communicate with ground and tower in class D before you took off, but couldn't on the return trip? A switch on the com panel was left in the auto position which was supposed to be down I can't think of what that would be or even why something like that would be in place - doesn't seem to serve a function.

I can't think of any configuration where you can transmit but can't hear except if your Com button was stuck, in which case you'd be stepping over the entire tower communications for everyone, if the jacks on your side broke, in which case you'd switch you plugs to the co pilot jacks, or if your headset simply broke (which it didn't since you could hear the ATIS).

In any case, please provide more information, maybe even a photo of this switch so I can get smarter and avoid any similar problems.

(I fly in a C172 N model FWIW)

Thanks -
 
WDD said:
Something just doesn't sound (no pun intended) correct. You were able to communicate with ground and tower in class D before you took off, but couldn't on the return trip? A switch on the com panel was left in the auto position which was supposed to be down I can't think of what that would be or even why something like that would be in place - doesn't seem to serve a function.

I can't think of any configuration where you can transmit but can't hear except if your Com button was stuck, in which case you'd be stepping over the entire tower communications for everyone, if the jacks on your side broke, in which case you'd switch you plugs to the co pilot jacks, or if your headset simply broke (which it didn't since you could hear the ATIS).

In any case, please provide more information, maybe even a photo of this switch so I can get smarter and avoid any similar problems.

(I fly in a C172 N model FWIW)

Thanks -
Click to expand...
Or he turned his COM#1 radio volume down temporarily to listen to ATIS on COM#2.
 
Confirm this with YOUR instructor, but:

Once you squawked non-comm, you should fly at the top of the Delta airspace directly towards midfield and circle. The tower will see your squawk and position and get the light guns going. Then follow the instructions via the light.

I was on my first solo cross country when I lost the whole stack. I landed at a nearby non-towered airport, kept the prop spinning, and called the tower from my mobile phone to tell them the situation. They were very helpful, told me the procedure above, offered to review the gun signals, I read them back from my knee board, they said sounds like a plan, see you soon.

All in all, sounds like you did the right stuffs.
 
Here's something that could have happened (or could happen to someone on a cross-country): Suppose........

You've got "COM 1" button turned on. Take off. Can hear everything. Everything's great.
It comes time to do the VOR navigation thing. So you tune the VOR, and then turn on the "NAV 1" button so that you can listen to the Morse code to identify it, like your instructor showed you how to do. Turn the Nav volume up to hear it clearly.
You listen to the Morse code, and feel that rejoicing feeling because everything is going great! Turn the Nav volume back down, because that static is really loud.
You go to turn the "NAV 1" button back off again, but accidentally turn the "COM 1" button off instead.
Now you'd still be transmitting, but not hearing anything. You'd actually still be listening to NAV 1, but if you had turned the volume down you might not notice that the Morse code is still there.

Just a thought. Possible?


Edit: not saying this almost happened to me yesterday. No, not saying that at all. ;)
 
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Yes, but if he turned Com 1 off, then he wouldn't be transmitting on Com 1, but the tower said they could hear him.

The only thing that makes sense is that he somehow turned the volume all the way down on an active Com 1, as he could still hear Com 2 ATIS.
 
On a very common audio panel, there is one "knob" that controls which COM you're transmitting on, and (separately) a "push-button" that controls what you listen to.

KMA-24-Audio-Panel.jpg

The top row of push-buttons sends audio to an overhead speaker. The bottom row sends audio into your headset. The knob on the right (12) controls where transmissions go.

Most of the time, the "COM1" button (4-bottom) is pressed in, and the knob is also set to "COM1". Audio both in and out from COM1.

So "pressing" the NAV1 button (6-bottom) just lets you additionally listen to Morse code, and has nothing to do with transmitting.
By the same token, if you "un-press" the COM1 button by accident, but don't touch the knob on the right, you'll be transmitting successfully and just not hearing anything.


Edit: fixed graphic, and button numbers
Edit2: OP, if you take a photo of your audio panel, I bet we could clear this right up!
 
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So the top switch for speaker and phone was in auto. And it was working for over 30 minutes over Lake Matthews which is our practice area. Don’t know why it disconnected. I had just got ATIS for airport and made my call but didn’t get a reply. That’s when it cut.
 

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It's possible there was an intermittent failure which was blamed on a switch because it's easier than going on a scavenger hunt trying to figure out what's wrong with it. That audio panel is at least 40 years old. It's also possible the switch was bumped accidentally in flight. I've seen both.

Renesh Kumaresan said:
So the top switch for speaker and phone was in auto. And it was working for over 30 minutes over Lake Matthews which is our practice area. Don’t know why it disconnected. I had just got ATIS for airport and made my call but didn’t get a reply. That’s when it cut.
Click to expand...

So where was the auto switch? Saying the auto switch "was in auto" doesn't make sense. It's a three-position switch. Top is speaker, middle is off, bottom is headphone. It is called the auto switch because it automatically selects audio from the same source as the transmitter. But there is no position simply called "auto", that's just the name of the switch.
 
Clip4 said:
Normally radio failures are due to the pilot. Tell your CFI he needs to make sure you understand the audio panel before he signs his students off for solo.
Click to expand...

Seems especially important when you're instructing at a towered airport.
 
Sorry it was in the middle position which is the auto select position. For the audio panel to select the source between the speaker and headset.
 
Renesh Kumaresan said:
Sorry it was in the middle position which is the auto select position. For the audio panel to select the source between the speaker and headset.
Click to expand...

The middle position is not the auto position. It is the "off" position.
 
kath said:
On a very common audio panel, there is one "knob" that controls which COM you're transmitting on, and (separately) a "push-button" that controls what you listen to.

View attachment 79155

The top row of push-buttons sends audio to an overhead speaker. The bottom row sends audio into your headset. The knob on the right (12) controls where transmissions go.

Most of the time, the "COM1" button (4-bottom) is pressed in, and the knob is also set to "COM1". Audio both in and out from COM1.

So "pressing" the NAV1 button (6-bottom) just lets you additionally listen to Morse code, and has nothing to do with transmitting.
By the same token, if you "un-press" the COM1 button by accident, but don't touch the knob on the right, you'll be transmitting successfully and just not hearing anything.


Edit: fixed graphic, and button numbers
Edit2: OP, if you take a photo of your audio panel, I bet we could clear this right up!
Click to expand...

why don’t you use auto?
 
kath said:
On a very common audio panel...
Click to expand...

This. Or the volume.

I've seen it before even with experienced pilots. If the auto switch is off or inop (and yes, placarded), then when you choose the other radio with the dial knob, you have to also use the buttons to choose the radio you want to listen on. The odds are, the OP was listening, just listening to the other radio.

Why not auto? I dunno, for some reason some people don't like the auto button and turn it off. I don't understand why, but they do.
 
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After seeing your recent posts, I'm going to have to say it was equipment going bad - nothing you did. It worked perfectly in the Auto position as you stated, you didn't move it, and it quick working. It's a 40 year old panel. Thus, I hope the flight school is fixing it and not taking the easy route and say you moved the switch.
 
WDD said:
After seeing your recent posts, I'm going to have to say it was equipment going bad - nothing you did. It worked perfectly in the Auto position as you stated, you didn't move it, and it quick working. It's a 40 year old panel. Thus, I hope the flight school is fixing it and not taking the easy route and say you moved the switch.
Click to expand...

Nope, he is confused about how it works. He said the switch was in the middle position, which he called the "auto" position, but it is actually the "off" position.
 
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