Pretty straightforward question... If I make an emergency broadcast on 121.5 is anyone outside of an aircraft monitoring going to hear it?
Does ATC monitor 121.5?
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steingar
Taxi to Parking
Yup. Can't say who, but every time I hear a peep on 121.5, I immediately hear a grumpy voice say "you're on guard".
sba55
En-Route
Yes, pretty much all of them monitor 121.5. There are a few exceptions and those are usually listed in the AF/D - eg. 121.5 unmonitored or not available. Most military installations monitor this as well, in addition to many airliners.
Ted
The pilot formerly known as Twin Engine Ted
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iFlyNothing
In my experience, that's mostly other pilots.
But yes, ATC does monitor guard and will respond if they hear you. I've had success with getting their attention that way before.
The catch: They don't have 100% coverage, just like with the rest of their radios.
FlySince9
En-Route
I used to be one of those grumpy voices... SAC Command Post 1974-1994
Matthew
Touchdown! Greaser!
Don't know the answer to the question - but I'd say it's a definite maybe. Maybe ATC, maybe some other pilot.
I've always wondered about this comment in the AF/D for my class D:
>
COMM/NAV/WEATHER REMARKS: Freq 121.5 not available at tower.
<
I've always wondered about this comment in the AF/D for my class D:
>
COMM/NAV/WEATHER REMARKS: Freq 121.5 not available at tower.
<
bob_albertson
Pre-takeoff checklist
If you have an emergency outside of their airspace and you don't know the tower's frequency then you still can't get ahold of them on 121.5.
Another scenario might be if you were planning on a cross country where you wanted to remain within earshot of a facility that could hear your ELT then you might want to re-route yourself.
May be off, but they seem like logical reasons why publishing that note in the A/FD is pertinant.
Bob
HPNPilot1200
En-Route
Yes, but not all positions may be required to monitor per the facility specific SOP. For example at A90 (Boston), 121.5/243.0 are available at all positions but only the Bedford sector (SB ) and Manchester FDM (flight data management) position are required to monitor these frequencies.
Here's the RDVS (rapid deployment voice switch) display at CMH TRACON with the emergency frequencies in red on the lower right.
Here's the RDVS (rapid deployment voice switch) display at CMH TRACON with the emergency frequencies in red on the lower right.
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denverpilot
Tied Down
As others have said, "someone" will answer.
Some facilities I've talked to when hunting ELT's will say stuff like, "Oh, we have an ELT? Let me go turn up the 121.5 receiver... oh, yep, I hear it too!" These were Towers, typically.
So they obviously weren't listening, nor apparently required to.
And a little unknown fact about the SARSAT birds -- they could "hear" a carrier just as well as an ELT, and if you could keep a radio keyed in the backcountry for long enough, someone would come lookin'... wouldn't work with most handhelds because the battery would be dead too soon, but if you were sitting with a downed aircraft, you could mash the transmitter on...
Of course, a lot of airliners also monitor GUARD, so probably easier to just keep calling normally on it if you're too low to be heard by an ATC facility and not just key the transmitter with no audio. But in a pinch, SARSAT would have "hit" on just the transmitter.
No such fun with the new birds listening on 406 MHz, since none of us are carrying a radio that will transmit there other than the new ELTs.
steingar
Taxi to Parking
Well try and cheer up.
Fearless Tower
Touchdown! Greaser!
The good news is that if your over water and there is a USN ship within range, it will be monitoring IAD 121.5......assuming they don't have the volume turned all the way down...... If you are over blue water and have an emergency, first priority would be to switch the squawk to 7700 (or 75/7600 as appropriate) - that will trigger our console alarms regardless of what the speaker volume is set to.
Really, that is good to know. Do you pick up/monitor all transponders or just emergency beacon signals? Makes sense, not like you guys don't have the radar power for it....
Fearless Tower
Touchdown! Greaser!
IFF will interogate/pick up any Mode IIIC code (which is what an aviation xpdr squawks) plus the other military modes.
The consoles have separate alarm boxes that go off if it picks up a 75/76/7700 signal. It will also alarm/pick up 121.5/243.0 ELT signals....but that usually only goes off when a helo has a hard landing on deck.
gismo
Touchdown! Greaser!
Not much point listening on 406, AFaIK those are just data signals. No voice or whoop whoop there to hear. Prolly sounds more like "BZZZT" if you can hear anything besides white noise.
It's a 450msec blip of data every 50 seconds. Dont think you can hear it, but Becker does make a DF system to home in on the 406Mhz portion of the signal. Pretty nifty box with a slightly bulky antenna pod for the bottom of the fuselage:
http://ar042swrcap.org/htdocs/Training/Training_Media/ES/MO/Becker/Becker_SAR_DF-517.pdf
ebacon
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Bounces Three Times
I accidentally transmitted on 121.5 once. It was in the vicinity of Ft. Knox and a response was immediate. 
Jim_R
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Jim
Not always in that order. Last weekend, I was monitoring 121.5 during a XC, and after an hour of silence, I suddenly hear a grumpy voice say, "You're on guard!"
It was followed quickly by another, more whimsical voice saying, "No he's not!"
Fearless Tower
Touchdown! Greaser!
The best ones are when someone is actually talking to ATC on 121.5 due to an actual emergency and some Guard Nazi jumps in with the 'You're on guard' comment.
denverpilot
Tied Down
You can. And if you've got Doppler DF gear, you can home on it. It'll just take you a lot longer than a continuous signal. If you're clueless and don't know that it goes on and off, you'll also be quite confused at what's coming out of your DF gear.
(Listened to a CAP aircrew aloft trying to figure that out once on a real search, who should have known better. Got annoyed listening to it too and almost keyed up the FM to straighten them out, but relaxed and waited until the Incident Commander took care of it. Over the air.)
The problem is... not much DF gear out there that has a 406 receiver built-in. You pointed out the Becker, which is a neat little system, and there's some others but they're all way out of the price range of individual ownership. Not like the good ol' days of the L'il 'Elper and cheap DF gear. I own one of those. I'll never own a Becker.
Cheaper Doppler gear exists, sometimes in kit form, and it typically just needs a receiver that'll go there, but not many hobbyist folks have receivers that'll do 406 MHz. Any serious radio geek had a traditional Aviation band receiver.
I've hunted ELT's with phone calls to ham operator's houses before... "Hey Bob, are you hearing anything on 121.5 up there from the vertical on your tower? No? Can you swing your beam? You've got something at 030? Thanks."
A few phone calls, a map, cross-bearings... you're standing at the old style ELT ready to turn it off in however long it took you to drive there.
Of course, finding hams who can actually even have towers anymore... is becoming a challenge...
Ted
The pilot formerly known as Twin Engine Ted
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iFlyNothing
Yeah, that one annoys me. I heard that the other day. Response: "Yeah, I'M TRYING TO BE ON GUARD!"
What's funny is when everyone starts talking with funny accents "En gard!"