Author Topic: Faint ELT heard  (Read 27721 times)

Offline dan9125

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Faint ELT heard
« on: April 04, 2006, 02:47:38 PM »
Two aircraft heard faint ELT (emergency locator transmitters) today on 125.200mhz cleveland center around 2:30pm. Anyone alse catch this? I think they transmit on 121.500 mhz.

  Dan



Offline digger

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Faint ELT heard
« Reply #1 on: April 04, 2006, 03:52:31 PM »
I'm confused--they heard the ELT on 121.5, or 125.2 ?

121.5 would be the normal frequency for ELTs. That, or 243.00, in the UHF band.

Also, CAP can use 121.6 or 121.775 for ELT practice beacons.

Offline KSYR-pjr

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Re: Faint ELT heard
« Reply #2 on: April 04, 2006, 03:52:33 PM »
Quote from: dan9125
Two aircraft heard faint ELT (emergency locator transmitters) today on 125.200mhz cleveland center around 2:30pm. Anyone alse catch this? I think they transmit on 121.500 mhz.


Hearing an ELT on 121.500 is not all that uncommon an event.   Fortunately, most of these are false alarms and the aircraft is found parked innocently at an airport, the ELT triggered by a hard landing or some other innocuous event.

In the last few years of flying over the northeast US, I have been asked by ATC to listen for an ELT four times.

Offline digger

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Faint ELT heard
« Reply #3 on: April 04, 2006, 04:11:37 PM »
Quote
...the ELT triggered by a hard landing or some other innocuous event.


Yeah, like being removed from the airplane and put in a flight bag, which upon the pilot's arrival at home, is casually *tossed* into a closet...

 :roll:

Offline bcrosby

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Faint ELT heard
« Reply #4 on: April 04, 2006, 05:48:41 PM »
yeah... also..

you are allowed to test your ELT during the first 5 minutes before every hour UTC... ie:

12:55 UTC
01:55 UTC
02:55 UTC
03:55 UTC

etc..

but it shouldn't be on for more than a few seconds.

Offline Jason

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Faint ELT heard
« Reply #5 on: April 04, 2006, 06:52:07 PM »
Quote from: bcrosby
yeah... also..

you are allowed to test your ELT during the first 5 minutes before every hour UTC... ie:

12:55 UTC
01:55 UTC
02:55 UTC
03:55 UTC

etc..

but it shouldn't be on for more than a few seconds.


I'm not sure of the regulations for where you are referencing to, but IIRC you are only allowed to test your ELT during the first 5 minutes after every hour.  The AIM states/suggests:

Quote from: AIM 6-25, sub-para b Emergency Locator Transmitter (ELT)
(a) 1. ELTs should be tested in accordance with the manufacturer's instructions, preferably in a shielded or screened room or specially designed test container to prevent the broadcast of signals which could trigger a false alert.

2. When this cannot be done, aircraft operational testing is authorized as follows:

(a) Analog 121.5/243 MHz ELTs should only be tested during the first 5 minutes after any hour. If operational tests must be made outside of this period, they should be coordinated with the nearest FAA Control Tower or FSS. Tests should be no longer than three audible sweeps. If the antenna is removable, a dummy load should be substituted during test procedures.

(b) Digital 406 MHz ELTs should only be tested in accordance with the unit's manufacturer's instructions.

(c) Airborne tests are not authorized.


So, if you were going to test an ELT via what the AIM suggests, those times would be:

01:05 UTC
02:05 UTC
03:05 UTC
and so forth...

Good discussion we have going here!  Very informative as well; I learn new things every day.

Regards,
Jason

Offline KSYR-pjr

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Faint ELT heard
« Reply #6 on: April 04, 2006, 08:12:51 PM »
The personal locator beacons, like this one linked here, also are tested at the first five minute block after the top of the hour.

http://www.mcmurdo.co.uk/?Menu=17&Page=/Contents/ListProducts.asp&ID=1025

This is the unit I carry with me when I fly.

Offline Jason

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Faint ELT heard
« Reply #7 on: April 04, 2006, 08:29:07 PM »
Quote from: KSYR-pjr
The personal locator beacons, like this one linked here, also are tested at the first five minute block after the top of the hour.

http://www.mcmurdo.co.uk/?Menu=17&Page=/Contents/ListProducts.asp&ID=1025

This is the unit I carry with me when I fly.


Nice product.  I hear the 406MHz ELT's are very good and eventually are going to replace the 125MHz ELTs. (COSPAS-SARSAT will cease satellite monitoring of the 121.5 MHz frequency on February 1, 2009.)

Hopefully none of us will have to use one beyond the sake of testing.  Even then, be very cautious as I know many people in CAP who are called on 5+ hour missions because of an ELT going off, only to find it was set off accidentically by someone in a moving truck, or boat, etc.  Ask your local CAP squadron, I'm sure each one has a set of their own stories and memories.

Jason

Offline JALTO

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Faint ELT heard
« Reply #8 on: April 04, 2006, 08:41:29 PM »
Funny this should come up....I was headed out to Ohare yesterday morning on United and heard over channel 9 Cleveland center asking pilots if they hear the "faint ELT"...I had no idea what an ELT was till this post came up!  So apparently this was going on before 2:00PM as well.  

-J

Offline KSYR-pjr

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Faint ELT heard
« Reply #9 on: April 04, 2006, 09:01:13 PM »
Quote from: Jason
Hopefully none of us will have to use one beyond the sake of testing.  Even then, be very cautious as I know many people in CAP who are called on 5+ hour missions because of an ELT going off, only to find it was set off accidentically by someone in a moving truck, or boat, etc.  


With a built-in GPS that sends the coordinates of the unit's location to the satellites along with the distress signal, this unit better have a rescue response time of much less than five hours.   At least there is a claim that rescue operations start within minutes of receiving the signal.  I suppose location of the unit will determine the actual response time.

Interestingly, there is a warning in the McMurdo user manual that reads something to the effect, "Do not activate this unit unless all other means of rescue have been exhausted or do not exist, including walking out of the area to reach civilization to request assistance."

Here is the home page of the US Gov't agency that monitors the 406 MHz frequency and initiates the rescue response:

http://www.sarsat.noaa.gov/

Offline digger

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Faint ELT heard
« Reply #10 on: April 04, 2006, 09:48:03 PM »
Quote
Even then, be very cautious as I know many people in CAP who are called on 5+ hour missions because of an ELT going off,...


As far as that goes, if you crash and yours goes off, it could very well be 5+ hours before anybody gets out to start looking for you.

Also, in some cases, CAP's repeaters monitor 121.5, and if there is an ELT transmitting within range of the repeater, it can be heard on a CAP assigned frequency.

Offline KPryor

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Faint ELT heard
« Reply #11 on: April 05, 2006, 10:15:37 AM »
I heard two different aircraft yesterday on my scanner in my area reporting that they were receiving an ELT signal.  I could only hear half the conversation, so I don't know what they were told.
KP