ELT Mission Procedures after SARSAT Turned Off??

[RADIOMAN015]

Well we are approaching the date with the SARSAT will be turned off, and will no longer listen for 121.5 or 243.0 mhz alert/homing signals.  Locally, I haven't seen a rush by private/recreational pilots to change out their equipment to the more expensive 406.0 mhz. So there's going to be a lot of private aircraft with just the old alert/homing signals ELT transmitters!!

I noted in the last edition of the "Volunteer", that the Operations Directoriate feels that it is going to take more of CAP resources to track down an older ELT in the past.  At least in our wing, mum has been the word.  No one has really said anything as to how procedures will change within the wing.

Locally, I think we will conduct more squadron ELT ground training excises to validate some mobile operations concepts, since I think without air support DF it will be significantly more difficult to track these down.  (As an example in the past although we had a SARSAT hit that pretty much confirmed the location, the tower at the other end of airport, could not audibly hear the signal). 

Anyone else doing more training or have gotten higher headquarters guidance on what to expect?

RM     

[jeders]

Our end isn't going to change that much, other than we won't have SARSAT cooridinates to start with. Instead we'll have areas like, "ELT heard 5 miles from end of runway on a heading of 210, went silent 3 miles from end of runway." Airliners, and hopefully GA pilots, will listen to 121.5 and notify the FAA who will then notify AFRCC. From there activation is just how it is now, so no real change in procedures. Instead we'll probably see more flying in the initial part of missions to nail down the signal. So if anything, you should be getting more aircrews trained and make sure they all know how to use the DF equipment in the aircraft.

[JoeTomasone]

There are a few threads discussing this in some detail; you might wish to read some of them as well.

[RADIOMAN015]

The challenge is going to be IF our aircraft can't fly because of weather conditions; than it could become a significant resource requirement for alerting & dispatching ground base DF teams over a much wider area.

One of our member's who is a retired commercial (airline & freight) pilot, has told me that in many instances the 121.5 mhz receiver may be turned down or even changed to another frequency when they start their descent into an airport.   Two other members that our military cargo aircraft pilots have stated that as they fly at cruise altitude throughout the US there's many ELT signals that they hear and they appropriately alert the FAA ARTCC about. 

However, this a much more difficult method to pin down the signal, because aircraft don't have signal strength indicators on the radios, & IF most aircraft are flying at the same altitude (especially if there's bad weather), most are going to  pickup and lose the signal at the same points.  ARTCC or Approach/Depature Control, might have to be start requesting aircraft at lower altitudes to quickly monitor the frequency in order to get a better idea as to the signal's geographic area. 

My guess is many signals will never be found because they won't be heard by overflying aircraft, or the batteries will die before the ground DF team can even get into the area.

I know General Aviation aircraft are not going to be required to change to the new 406 mhz data ELT, unless their current 121.5 mhz homing signal ELT breaks & has to be replaced.   That's probably going to be quite awhile overall (5 to 10 years??)!!!!

RM 

Our end isn't going to change that much, other than we won't have SARSAT cooridinates to start with. Instead we'll have areas like, "ELT heard 5 miles from end of runway on a heading of 210, went silent 3 miles from end of runway." Airliners, and hopefully GA pilots, will listen to 121.5 and notify the FAA who will then notify AFRCC. From there activation is just how it is now, so no real change in procedures. Instead we'll probably see more flying in the initial part of missions to nail down the signal. So if anything, you should be getting more aircrews trained and make sure they all know how to use the DF equipment in the aircraft.

[JoeTomasone]

If you don't replace your 121.5 with a 406 in your aircraft, you're making a potentially fatal mistake, no doubt about it.    The points concerning the increased need for aircraft to narrow down a search area are right on target - but what should also be emphasized is the need for re-focused training and equipment on the GT side.    Ground Teams will have to learn how to receive signals from longer distances - which will require much more radio theory than most have ever been exposed to.   I suspect that the L-Per beam antennas will become more popular in the New Year.   I, personally, am planning on picking up as big of a 2 meter beam as I can reasonably fit in the Jeep.

And, as mentioned in the scanner thread, it certainly wouldn't hurt to have lots of members, preferably with decent gain antennas on the roof of their homes/cars who can respond to a callout and see if they have a signal at their location.

[Major Lord]

I have been working on a project for awhile that uses a small APRS (like packet ) digipeater (Ham band stuff) and a 121.5 receiver. The idea is that the Digipeaters will receive 121.5 signals, and report them via the APRS network to a mapping program. The signal strenth and height of the antenna will determine how large a circle is drawn on the map. When circles from various receiver/digipeaters overlap, the ELT is likely to be nearby.

The plan in broad strokes is this:

1) Establish a ham radio "club" with a club call sign, consisting of CAP people who are hams.

2) Find those ( in California) who have access to really high spots, mountains, office buildings, etc.

3) I will provide the digipeater and 121.5 receiver at my cost to any ham who wants to adopt one, and has a high place to plant it. ( and can package, power and add antennas) Naturally, the digipeater could still act as an APRS digipeater.

4) Phase II will add a 406.25 receiver to the digipeater.

Obviously this can't be a CAP project. It would have to be a ham project in support of SAR.

My friend Greg at Openaprs.org would provide a mapping page that would only be available to us, to keep the news media and ambulance chasers from racing us to the predicted location.

I don't have great faith that 406 ELT's ( or PELTs) will give us 100 % perfect information. Its that whoe thing about being dropped out of the sky and bursting into flames that somewhat detracts from their position accuracy. I think Ground and A/C RDF is not quite dead.

[JoeTomasone]

The idea is that the Digipeaters will receive 121.5 signals

I don't see how since there won't be AX.25 data encoded on it.   An unmodified packet system can't do anything intelligent with non-data signals.   I suppose that firmware could be written to recognize the sweep tone (as it is predictable), but that would be quite an effort. 

How do you plan to have the TNC recognize the 121.5 signal (and differentiate from voice traffic)?

[Major Lord]

Joe,

The digipeater will actually have two receivers in it: one for receiving packets on 144.390, and one to just listen for any signals on 121.5 and report their amplitude at the receiver. An ELT may or may not contain a sweep tone, so I would not exclude carrier-only signals. The I-gated info would create a log of anyone keying up on 121.5 and the RSSI at the time. This might help identify brief MAYDAY call attempts, and create an archival record of brief ELT/PLB/EPIRB activations. I am anticipating that ELT signals will be more persistant than voice traffic.

We have a back-burner project to write decoding firmware for the Manchester encoded data stream for the 406 part. Without this, I am not sure there is any point in reporting signal strength on 406. TBD

Both of these bits of intel would be reported by the digipeater as AX.25 packets. The driving engine for this is my Micro-Trak TT4 (http://www.byonics.com/microtrak/mt-tt4.php) but it could be done with any digipeater than can decode analog values and send telemetry packets.

[DNall]

It changes nothing whatsoever for CAP. When FAA gets a missing aircraft alert, we go look for them & there usually are not ELT hits. In fact, I don't recall ever finding a downed aircraft with a working beacon. When you don't have hits, you try to use other data (radar, witness, etc). That's all PSC.

People that choose not to upgrade their gear are statistically ensuring they won't be found for well over a week a day, and a greater chance of not being found at all.

In practice, we may have a few more redcaps that turn out to be false alarms, but that's short term. In the long run there'll be less ELT/missing aircraft related missions tasked to CAP - and that's a good thing cause it means AFRCC is being more efficient.

[jeders]

Quick (slightly) off-topic question.

The new 406 beacons also transmit on 121.5, but the 121.5 signal is supposedly weaker than current beacons. Is there anything against having both a 121.5 and 406 beacon installed in an aircraft so that you have the stronger 121.5 signal?

[SarDragon]

The two 121.5 signals would interfere with each other.

[lordmonar]

Quick (slightly) off-topic question.

The new 406 beacons also transmit on 121.5, but the 121.5 signal is supposedly weaker than current beacons. Is there anything against having both a 121.5 and 406 beacon installed in an aircraft so that you have the stronger 121.5 signal?

Also...if you have the 406....then you don't need a stronger 121.5.  COPAS will give a 406 location that is supposed to be within 3 Miles of the target (vice to 20 miles we get with SARSAT).   Having a stonger 121.5 just is not necessary with 406.

On the note of how will we be tracking down 121.5 signals.....it will be pretty much the same as now....AFRCC will give us the coordinates of the station that heard the signal (be it an Airborne Aircraft, FAA facility, or what not).  We would go to those coordinates first and start working the signal.

It does mean that we will be working with a much larger circle or probabilty making our jobs harder.....it also means that we will not get called out at all because noone ever hears the signal in the first place.

My guess is that the FAA will mandate 406 eventually....it will probably only happen after a high pofile crash where the 121.5 signal was working but no one heard it in time to actually help the victimns.   It is sad, but with the political opposition to mandating this safety item it seems that is going to be the only way to get everyone to change to 406.

[NC Hokie]

The new 406 beacons also transmit on 121.5, but the 121.5 signal is supposedly weaker than current beacons. Is there anything against having both a 121.5 and 406 beacon installed in an aircraft so that you have the stronger 121.5 signal?

My understanding is that 406 gets us sent to the right neighborhood and that 121.5 is just strong enough to help us find the right address.

My guess is that the FAA will mandate 406 eventually....it will probably only happen after a high pofile crash where the 121.5 signal was working but no one heard it in time to actually help the victimns.   It is sad, but with the political opposition to mandating this safety item it seems that is going to be the only way to get everyone to change to 406.

Kind of like how 121.5 got mandated in the first place.

[sardak]

The quality of airborne reports will vary considerably.  Very often, and I just had one yesterday, the format is:
Sidney 240 at 50, FL 410 -> So the airliner was at 41,000 ft, 50 miles from the Sidney VOR on the 240 degree radial.  From how big of an area do you suppose that plane could receive an ELT signal? It was somewhere in SE Wyoming, SW Nebraska or northern Colorado. Maybe even in NW Kansas.  Now where do you start?  Which wing/region gets the mission?
A good report will include the position when the signal was first heard and the position when the signal faded.  My experience is that maybe 1 in 4 airborne reports includes that information.

When FAA gets a missing aircraft alert, we go look for them & there usually are not ELT hits. In fact, I don't recall ever finding a downed aircraft with a working beacon.

That's unfortunate and it's also discouraging. But there are crashes in which the ELT does work, which is why we try not to ignore them.

I know General Aviation aircraft are not going to be required to change to the new 406 mhz data ELT, unless their current 121.5 mhz homing signal ELT breaks & has to be replaced.

Nope, replacing an ELT does not require installing a 406 beacon. It only requires that the replacement be C-91a qualified, which is "generation 2," with 406 ELTs being "generation 3."

The Denver metro area has an ELT monitoring system but not as sophisticated as Major Lord is working on. There are monitors at 7 or 8 airports and one on top of an 8300 ft mountain. When a monitor detects a signal on 121.5 or 243.0, the system:

a. keys a ham repeater which transmits a digital voice identifying the monitor and frequency of the signal, and transmits the audio of the received signal, repeating every 90 seconds;

b. pages the members of the organization that owns the monitors, giving the monitor ID and frequency;

c. posts the data to the Internet at: http://www.fredf.org

On the website, select "Daily ELT Information."  This brings up drop down boxes for year, date and month. No listing for a particular day means no signals received (or that the system wasn't working  ). Looking at 12/22/2008 shows all signals being received by the "Repeater" which means the mountaintop site. On 12/19 there are multiple sites (airport IDs) which received a signal sequentially, most likely a moving signal.

Each monitor is DTMF (touch-tone) remotely controlled for on/off, frequency selection and sensitivity. The repeater can be monitored by anyone with a scanner or ham radio.

The system has allowed beacons to be located and shut off before Sarsat detected them. A number of real crashes have been detected by the system. There are times when Sarsat received signals that the system didn't.

Mike

[JoeTomasone]

Joe,

The digipeater will actually have two receivers in it: one for receiving packets on 144.390, and one to just listen for any signals on 121.5 and report their amplitude at the receiver. An ELT may or may not contain a sweep tone, so I would not exclude carrier-only signals. The I-gated info would create a log of anyone keying up on 121.5 and the RSSI at the time. This might help identify brief MAYDAY call attempts, and create an archival record of brief ELT/PLB/EPIRB activations. I am anticipating that ELT signals will be more persistant than voice traffic.

We have a back-burner project to write decoding firmware for the Manchester encoded data stream for the 406 part. Without this, I am not sure there is any point in reporting signal strength on 406. TBD

Both of these bits of intel would be reported by the digipeater as AX.25 packets. The driving engine for this is my Micro-Trak TT4 (http://www.byonics.com/microtrak/mt-tt4.php) but it could be done with any digipeater than can decode analog values and send telemetry packets.

Interesting...   If you get bored one day and feel like sharing some details...  joe@ab2m.net.

[RADIOMAN015]

See article at:
http://www.usatoday.com/news/nation/2009-01-07-beacon_N.htm
"Pilots Slow to Buy New Digital Emergency Beacons"
Esimates are only 15% of general aviation aircraft owners have purchased the new beacons.  Good background information provided on the history of ELT's in the article
RM

[bosshawk]

Dennis Nall: just to set the record straight: I have two Distress Finds of crashed airplanes and we located them both from the ELT signals.  So, the blankety, blank things do work at times.

[Al Sayre]

My best guess is we will do a lot more flying for ELT's that used to just require a run out to the local airport for a UDF team.  When an airliner reports hearing one lets say "at 37,000 ft passing 25 miles north of Jackson VOR"  I will probably try to get a Becker equipped aircraft up as high as possible and heading for Jackson.  There are at least 40 airports in a 50 mile radius of Jackson.  UDF/GT's alone will be hopeless, it's just too much area to cover on the ground in a reasonable amount of time.  We are also going to have to depend a lot more on the GA community and the ATC/FSS folks to get us PIREPS to help narrow it down without ending up with a bunch of folks out flying search patterns on their own.

[brasda91]

My Wing ES guy paged me yesterday needing to know if my Elpers were 243 capable or just 121.5/121.775.  Needed the info prior to 1700hrs today.  Didn't say why.

[MikeD]

Anyone know what the story is on airliners and other non-GA aircraft?  What about military, local govs, etc?  And for the love of all that is Holy, please tell me CAP's pretty far along in upgrading to 406 MHz? 

[RADIOMAN015]

My best guess is we will do a lot more flying for ELT's that used to just require a run out to the local airport for a UDF team.  When an airliner reports hearing one lets say "at 37,000 ft passing 25 miles north of Jackson VOR"  I will probably try to get a Becker equipped aircraft up as high as possible and heading for Jackson.  There are at least 40 airports in a 50 mile radius of Jackson.  UDF/GT's alone will be hopeless, it's just too much area to cover on the ground in a reasonable amount of time.  We are also going to have to depend a lot more on the GA community and the ATC/FSS folks to get us PIREPS to help narrow it down without ending up with a bunch of folks out flying search patterns on their own.

Agree with your procedure BUT if there's bad, unflyable weather than we are really looking at significant use of ground resources.  Best bet is at least to find out what members are close to small airports, and perhaps some others (e.g. amateur radio operators, radio monitoring hobbyists, & small general aviation aircraft pilots/owners, that have an interest in this)  Basically it will be a matter of using a radio scanner/monitor (or aircraft receiver) to try to determine IF the signal is from that airport & than the UDF team can be dispatched with the professional DF gear.  IF it's not on an airport, than that's going to be VERY challenging!!! 

My understand is generally that commercial airline aircraft, are NOT monitoring 121.5 mhz when they start their descent into the destination airport, so ATC (approach/departure control) is going to have to specifically request aircraft to monitor.     

I think locally we are going to run some additional squadron exercises using various radio scanner/receivers to determine effectiveness in receiving the signals.
RM   

[SJFedor]

Another cute little thing would be to make our repeaters capable of listening in on 121.5. No idea if it's possible though, i'm rather ignorant when it comes to comm stuff. 

[Chief2009]

My guess is that the FAA will mandate 406 eventually....it will probably only happen after a high pofile crash where the 121.5 signal was working but no one heard it in time to actually help the victimns.   It is sad, but with the political opposition to mandating this safety item it seems that is going to be the only way to get everyone to change to 406.

I'm pretty sure groups like AOPA and EAA will lobby very hard against this one. Aren't 406 ELT's pretty expensive?

DN

[arajca]

Another cute little thing would be to make our repeaters capable of listening in on 121.5. No idea if it's possible though, i'm rather ignorant when it comes to comm stuff. 

Not really possible. Our repeaters work in a different band and use a different signalling technique (FM vs AM), and the antennas are tuned for the band the repeaters use.

[flynd94]

My best guess is we will do a lot more flying for ELT's that used to just require a run out to the local airport for a UDF team.  When an airliner reports hearing one lets say "at 37,000 ft passing 25 miles north of Jackson VOR"  I will probably try to get a Becker equipped aircraft up as high as possible and heading for Jackson.  There are at least 40 airports in a 50 mile radius of Jackson.  UDF/GT's alone will be hopeless, it's just too much area to cover on the ground in a reasonable amount of time.  We are also going to have to depend a lot more on the GA community and the ATC/FSS folks to get us PIREPS to help narrow it down without ending up with a bunch of folks out flying search patterns on their own.

Agree with your procedure BUT if there's bad, unflyable weather than we are really looking at significant use of ground resources.  Best bet is at least to find out what members are close to small airports, and perhaps some others (e.g. amateur radio operators, radio monitoring hobbyists, & small general aviation aircraft pilots/owners, that have an interest in this)  Basically it will be a matter of using a radio scanner/monitor (or aircraft receiver) to try to determine IF the signal is from that airport & than the UDF team can be dispatched with the professional DF gear.  IF it's not on an airport, than that's going to be VERY challenging!!! 

My understand is generally that commercial airline aircraft, are NOT monitoring 121.5 mhz when they start their descent into the destination airport, so ATC (approach/departure control) is going to have to specifically request aircraft to monitor.     

I think locally we are going to run some additional squadron exercises using various radio scanner/receivers to determine effectiveness in receiving the signals.
RM   

I would actually hazard to say that most (if not all airliners) aren't monitoring 121.5 at all.  Generally, we set COM2 to our local company freq, ARINC region freq or SELCAL freq.  The only time we tune up 121.5 is if ATC requests us to.  Its in most company Operation Spec's on what is supposed to be put in COM2.

I agree with an earlier poster, as an IC I never gave much credit to an airborne report unless they were down low.  Too much of a foot print if the report is from FL370.  I have given many an airborne report from the FL's when asked.

We the turn off of the COPAS/SARST system we will be a little busier and, it will take more resources to prosecute a mission.  Don't worry, 406 beacons or COPAS/SARSAT will be mandated/turned back on when someone dies with a old-generation beacon.  In aviation change is best done with blood, sad but, true.

[PHall]

The cost of the 406 beacons will probably come down when they become mandatory since the manufacturers will be selling a lot more of them.
More sales usually results in lower unit costs, usually....

[nesagsar]

This means that ground teams will have to train even more in ground navigation, not a bad idea. Ideally (and sometimes nescesarily) a ground team should be able to find a target without aerial assistance.

[Al Sayre]

Another cute little thing would be to make our repeaters capable of listening in on 121.5. No idea if it's possible though, i'm rather ignorant when it comes to comm stuff. 

Not really possible. Our repeaters work in a different band and use a different signalling technique (FM vs AM), and the antennas are tuned for the band the repeaters use.

Not just that, but NHQ is in the process of issuing new repeaters.  Two of the caveats to get them is that only people authorized by NHQ can work on them (kind of like Aircraft Consolidated Maintenance) and no modifications to the repeaters...

[JoeTomasone]

Another cute little thing would be to make our repeaters capable of listening in on 121.5. No idea if it's possible though, i'm rather ignorant when it comes to comm stuff. 

Not really possible. Our repeaters work in a different band and use a different signalling technique (FM vs AM), and the antennas are tuned for the band the repeaters use.

Antennas know nothing about FM vs. AM.   The antenna itself would work (as the frequencies are not significantly different and reception is much less critical of antenna length than transmission is - think "police scanner" here and how many bands it can receive), however the duplexer (a device that allows you to use the same antenna for simultaneous transmission/reception without damaging the receiver) is tuned to precisely the receive frequency, and thus would filter out all other signals.   

Of course, nothing prevents mounting some sort of monitoring device at the repeater location.....

[lordmonar]

Anyone know what the story is on airliners and other non-GA aircraft?  What about military, local govs, etc?  And for the love of all that is Holy, please tell me CAP's pretty far along in upgrading to 406 MHz? 

We are upgrading.....I think as the planes go in for annual they are getting the 406 IIFC.  Either way the money is there and we are changing.  Don't know the status of the fleet though.

[es_g0d]

406 beacons (FAA TSO 126) are NOT mandatory, nor are they likely to become so in the United States anytime soon.  The AOPA and other organizations are generally opposed to such a mandatory requirement, and they often state the high cost of the unit as a contributing factor.

Canada has elected to make 406 ELTs mandatory in the future (I do not know the date offhand).

I agree that economies of scale will bring the price down.  I would expect to see benefits of the mandatory-in-Canada rule has been in effect for some time.

Personally, I'd like to see a two-pronged solution to get more 406 equipment into the field.  First, no new installations of TSO 91 ELTs (the standard 121.5 and 243.0 MHz ELTs) should be permitted after a reasonable date.  That will at least start the clock ticking down so that as equipment fails it will be replaced with 406 ELTs.  Second, strong encouragement should be given to the carriage of 406-enabled PLBs.  I won't detail how I think that should happen as it would involve more regulation.

The end result of the discontinuance of 121.5/243.0 monitoring is that you are going to see fewer missions in the field.  We will likely have a drop in membership as well.  The upside is that when you actually DO have a mission that you ought to be more likely to be helping during and actual incident instead of a false alarm.

Good luck and good hunting,
-Scott
www.CAP-ES.net

[RiverAux]

and they often state the high cost of the unit as a contributing factor.

I supose the high cost to the government of looking for a missing airplane without a 406 beacon is irrelevant to them....

[es_g0d]

In the minds of most aircraft owners, it is irrelevent to them!  If you spread the risk across the entire poplulation, maybe they have a point that the cost is unbearable at the individual level.  The FAA response will invariably be "Nexgen ADS-B will solve the problem," because that's the panacea.

The bottom line -- as we all know -- is that the United States is returning to the early 70s in terms of SAR response for most GA aircraft, and that will result in lives needlessly lost.

Good luck and good hunting,
-Scott
www.CAP-ES.net

[RiverAux]

You know, some states have their own law requiring ELTs on aircraft.....an enterprising person might get the state requirements changed to 406s...

[Stonewall]

Someone should have attended my class tonight... 

[RocketPropelled]

The bottom line -- as we all know -- is that the United States is returning to the early 70s in terms of SAR response for most GA aircraft, and that will result in lives needlessly lost.

Which is why I've been advising pilot groups to please, please, if possible, file and fly IFR; or file a VFR flight plan and get flight following if workload allows.

At least then it will slightly accelerate the alerting process should something bad happen.

[es_g0d]

Please forgive, but I made an observation today.

The planned end-of-broadcast for analog television signals is 17 Feb 2009.  The planned monitoring of 121.5/243.0 MHz is 1 Feb 2009.

Sadly, the change that will cause greater concern, panic, and ACTION is the one affecting "the boob tube."

Good luck and good hunting,
-Scott
www.CAP-ES.net