121.5

[deltaorkah]

Nz

In New Zealand 121.5 is our distress frequency.
It has no callsign, when a distress call is made the nearest monitoring station gives confermation and says who they are, weather it be another plane, CH INFO or OH CONTROL.

Airways New Zealand allocated us 128.95 as a chat freq. and 123.45 as an air to air remote, and out of range of ground stations freq.
the CAA will kick our ass if we use 121.5 as anything other than that.

 

[JLHDU]

a Cesna was calling Greenville (TX) Majors Airport yesterday on 121.5 and refered to it as guard. never did hear a response and I ended up locking it out. I always thought 243.0 was guard and 121.5 was distress.

121.5 Civil
243.0 MilAir

Here at ZDC the most we generally hear are ADIZ calls to VFR FLIBS straying too close to the Metro airports. Otherwise we don't hear much. We may attempt to use it to get ahold of aircraft if they go "No Radio Communications" NORAC, some people call it No Radio "NORDO" but these aircraft aren't NORDO because they do have a radio. Not all sectors here even have the capability to use the VHF/UHF Guard freqs.

-J

 

[illini52]

http://www.faa.gov/ATpubs/AIM/Chap6/aim0602.html

40.5 is the old FM guard freq from the days when Army helos didnt have UHF or VHF. I'd bet you won't hear anything there any more.

 

[Declared_Hostile]

Yes, every aircraft isn't REQUIRED to monitor, but they should whenever practical. Many airlines' policies say for pilots to monitor the freq. 121.5 is used to contact an aircraft that wandered in to restricted airspace, or by military aircraft to contact civilian planes that have been intercepted, to name a few uses.

And occasionally they get their switches confused. More than once I've heard a confused captain or first officer give their cabin briefing over guard. This of course generates a bunch of flak from other pilots and then 123.450 lights up with some juicy traffic razzing the guy who just did the cabin announcements over guard.

I've copied a couple of small plane crashes on guard. The whole "mayday! mayday! I'm going down short of the airport!" business. Quite frightening. Makes your blood run cold knowing that a guy just lawn darted his aircraft and is laying in the wreckage and there isn't a thing you can do to help him.

 

[jcj]

http://www.faa.gov/ATpubs/AIM/Chap6/aim0602.html

40.5 is the old FM guard freq from the days when Army helos didnt have UHF or VHF. I'd bet you won't hear anything there any more.

40.5 may not be very active but 40 mHz FM in general is still used often by Army Helo's

 

[jparks29]

It also is used by the military to contact civilian aircraft which have wandered into a restricted airspace, and those are pretty intimidating transmissions.

yup... SERIOUSLY intimidating.........

I heard quite a few of those transmissions on 9-11, from (I'm assuming) DC ANG pilots....it was... surreal to say the least... that day was "off" to begin with.. but when you start hearing "turn to heading XYZ immediately or you WILL be shot down........" it uhhh......yeah..... bad memories....

 

[WarDork]

Yes Sir i have.

Hey,
I have just heard some voices on the emergency frequency 121.5 this was at 4:20 ish Oct 23 2009.
I heard only 1 X 1. (Meaning barely hearing anything)
heard voices only for about 2 seconds (Very static) and then nothing.
On the bus drive home i saw a Aircraft about 2000 FT off the ground very close to the carp airport.

 

[RayAir]

The only thing I have ever heard on 121.5 was a pilot trying to call up Pontiac Tower, which is on 120.5,lol.
We used to always have 121.5 punched in as a secondary channel to monitor in flight.

 

[N9JIG]

I have 121.5 in a dedicated scanner most often and have fairly often heard pilots use this as sort of a calling channel ("Go to the Chatter Channel") or occasionally calling a Center or Approach not realizing that they are on 121.5.

Occasionally, perhaps every other week or so, I hear pilots trying to raise another aircraft that isn't answering the Center. If I were a hundred miles or so north of where I am I might have heard the guys trying to raise NW188 as it overflew Minneapolis.

I live about 10 miles from two fairly busy GA airports and 20 miles from ORD so I hear inadvertent ELT's pretty often, but less these days than in the past.

I do have a question: Do any military aircraft have ELT's on 243.0 like civilians have on 121.5?

 

[ATCTech]

FWIW, you guys might want to add 406.0 MHz to your scanner. As of February 1, 2009, ELTs on 121.5 are no longer monitored via satellite for emergency locating, at least in Canada. ONLY ground based receivers or other aircraft in range will hear and report 121.5 ELTs as active here.

There are dozens of links on the internet with details of the 406 MHz locating system. Among others, the 406 MHz locater transmit a unique IDENT that is easily cross-referenced the aircraft registration. An obviously 406 MHz is NOT a voice radio channel, it's just for locating beacons.

Bob

 

[nd5y]

FWIW, you guys might want to add 406.0 MHz to your scanner. As of February 1, 2009, ELTs on 121.5 are no longer monitored via satellite for emergency locating, at least in Canada. ONLY ground based receivers or other aircraft in range will hear and report 121.5 ELTs as active here.

There are dozens of links on the internet with details of the 406 MHz locating system. Among others, the 406 MHz locater transmit a unique IDENT that is easily cross-referenced the aircraft registration. An obviously 406 MHz is NOT a voice radio channel, it's just for locating beacons.

Bob

You will not hear anything on 406.0.
The new ELTs and EPIRPs transmit a wideband digital signal on several frequencies between 406.0 - 406.1 and it is only a short pulse about once per minute.
Some will still transmit the siren tone on 121.5 for direction finding on the ground.

I posted some links about this earlier this year
http://forums.radioreference.com/987948-post5.html

 

[nd5y]

I posted some links about this earlier this year

The links I posted in Jan no longer work.
The documents can be found here C/S T.xxx Series - Technical