dpansier

dpansier

Well Known Member
Looks like 121.5 MHZ ELT's may be on the way out.......... quickly

http://hraunfoss.fcc.gov/edocs_public/attachmatch/FCC-10-103A1.pdf





17. Discussion. After reviewing the comments, we conclude that we should prohibit the
certification, manufacture, importation, sale or continued use of 121.5 MHz ELTs. The USCG and
NOAA, as well as other commenters, support a prohibition on any continued certification, manufacture,
importation, sale or use of 121.5 MHz ELTs,
 
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I don't understand who has the power here but I carry a 121.5 MHz ELT per FAA rules. Seems like this would have to happen in concert with a NPRM to mandate a 406 MHz ELT.
 
Looks like the 121.5 ELT has gone the way of Freon R-12 - you can't make them or import them anymore, but you can fix the ones that are already here.

TODR
 
FCC controls the spectrum, and theoretically could prohibit the "use" of 121.5 MHz, essentially making our ELT into illegal transmitters. If they did that, they could essentially "force" us to upgrade to 406 MHz very quickly. They have moved spectrum users around like this before (although rarely). I think it is very unlikely that they would go this way.

If they do end denying the use of 121.5 MHz for ELTs, I hope that they remember to tell the ELT manufacturers at some point. Those guys are all busy right now certifying dual frequency 121.5 / 406 MHz ELTs. Those units won't be too sellable if FCC decides to prohibit the use of 121.5 MHz.

Typical government operation. I'm sure ADS-B will work out great.
 
The 121.5 has...

IowaRV9Dreamer said:
....
If they do end denying the use of 121.5 MHz for ELTs, I hope that they remember to tell the ELT manufacturers at some point. Those guys are all busy right now certifying dual frequency 121.5 / 406 MHz ELTs. Those units won't be too sellable if FCC decides to prohibit the use of 121.5 MHz.

Typical government operation. I'm sure ADS-B will work out great.
Click to expand...

...a useful purpose along with the 406 transmitter. A quote -

The KANNAD 406 SURVIVAL is designed to transmit on three frequencies (121.5, 243 and 406 MHz). The two basic emergency frequencies (121.5 and 243 Mhz ) are mainly used for homing in the final stages of the rescue operations. The 406 MHz frequency is used by the COSPAS-SARSAT satellites for precise pinpointing and identification of the aircraft in distress.

I believe the TSO requirements call out both frequencies...:)
 
Hahaha

FAA wasn't able to make all of us to buy a new ELT (406 mhz) so FCC are doing their JOB!!!!

Anyway in Chile we can't use 121.5 mhz ELT any longer, we (pilots/owners) are weak again Chilean FAA.:(
 
Are the ELTs mandated in Chile...

AirbusPilot said:
FAA wasn't able to make all of us to buy a new ELT (406 mhz) so FCC are doing their JOB!!!!

Anyway in Chile we can't use 121.5 mhz ELT any longer, we (pilots/owners) are weak again Chilean FAA.:(
Click to expand...

...406 units ONLY?

....or are they dual units 121.5/406 with the 121.5 used for short range homing?
 
az_gila said:
...406 units ONLY?

....or are they dual units 121.5/406 with the 121.5 used for short range homing?
Click to expand...

Hi Gil,

If you want to fly in Chile you must have a ELT that comply with TSO C126a, not sure if you need 121,5 for homing. Anyway I have an AK-451 in my 8 that units transmit on 121,5/243/406 mhz and This unit complied with Chilean regulations.

Cheers,
 
In the US...

AirbusPilot said:
Hi Gil,

If you want to fly in Chile you must have a ELT that comply with TSO C126a, not sure if you need 121,5 for homing. Anyway I have an AK-451 in my 8 that units transmit on 121,5/243/406 mhz and This unit complied with Chilean regulations.

Cheers,
Click to expand...

...the FAR 91.207 REQUIRES a TSO C 91a ELT.

http://rgl.faa.gov/Regulatory_and_G...0ca5c0070bd29144862569cf005f1030!OpenDocument

...and TSO C 91a covers 121.5/243 outputs ONLY. The 406 output is an addition to these lower frequencies.

http://rgl.faa.gov/Regulatory_and_G...b1e589c98200f886256dc900695b8c/$FILE/C91a.pdf

So, whatever the FCC says, at this time we must have a 121.5/243 output ELT to meet the FARs...:rolleyes:
 
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I just called AOPA. Apparently many other folks have as well. They are on it and the general view expressed by the person I talked to is that this is a mistake. I would not go out and buy a 406 MHz ELT based upon the FCC document listed above.
 
The funny thing about this is I believe I read in my ARTEX manual that the ELT not only broadcasts on 406mhz, but also on 121.5. So am I breaking the law? If I am, too bad. Come and get me, coppers.

Seems to me, though, that unless the FAA also bans the use of 121.5 ELTs, then you'd still be legal having one for its purposes, just not using it. Of course, if you use it, chances are you're dead anyway. What are they going to do about it?
 
Dick Knapinski from EAA just sent this:

Pilots Caught in Middle of Conflicting Federal Rules

EAA is working to remedy a situation where conflicting rules written by two different federal agencies will soon place pilots in a precarious position ? being in compliance with one but not the other.
On June 15 the Federal Communications Commission (FCC) published in the Federal Register a change to 47 CFR Part 87 that will ?prohibit the certification, manufacture, importation, sale, or continued use of 121.5 MHz emergency locator transmitters (ELTs) other than the Breitling Emergency Watch ELT.? Meanwhile, the FAA in 14 CFR Part 91.207, stipulates that U.S.-registered civil airplanes are required to have an approved automatic type emergency locator transmitter in operable condition attached to the airplane. The FAA does notspecify either 121.5 or 406 MHz, but the overwhelming majority of aircraft are equipped with 121.5 MHz units, meaning they would be in violation of federal law when it goes into effect 60 days after publication, or August 15, 2010.
EAA is working with fellow aviation associations to prevent this action and exploring all avenues of action to address this rule before it goes into effect.
?This regulatory change would impose a substantial and unwarranted cost on general aviation,? said Earl Lawrence, EAA vice president of industry and regulatory affairs. ?And this also creates a burden for the GA community and those ground-based rescue units that continue to use the 121.5 frequency to perform searches and save lives.
?At the very least the FCC action is being conducted without properly communicating with the industry or understanding the implications of its action,? he added.
The FCC rule also highlights the fact that threats to GA can come from many different agencies, and that agencies outside of the FAA do not necessarily understand the effects of their actions on aviation.
Both the 121.5 MHz and 406 MHz ELTs meet the FAA?s regulatory requirements if manufactured to the proper technical standard order. While satellites no longer monitor the 121.5 MHz frequency as of Feb. 1, 2009, the frequency is monitored by ATC, the military, and other pilots.
 
121.5 Usage

Does this mean they are also banning the use of 121.5 for an emergency? If they oppose the use of ELT's from using the frequency then wouldn't communications in an emergency with a transmitter on that frequency also be illegal or am I just reading between the lines?
 
N42AH said:
Does this mean they are also banning the use of 121.5 for an emergency? If they oppose the use of ELT's from using the frequency then wouldn't communications in an emergency with a transmitter on that frequency also be illegal or am I just reading between the lines?
Click to expand...

No, I don't think they're trying to ban the use of the 121.5 MHz channel outright. The 121.5 MHz channel is a designated channel in the middle of the aviation VHF comm band, it is universally used as the emergency comm channel, and it would make no sense what-so-ever for them to ban voice transmission on that channel. They're only trying to ban transmission on that channel specifically by ELT devices (not by comm radios) as a way to force us to switch to 406 MHz ELTs. That too is a fairly nonsensical/underhanded/bullyish tactic (not atypical of the FCC), but that seems to be all that's going on here.

As others have pointed out, the FCC wording seems to also imply that even the newer dual and tri-band ELTs, i.e. 406/121.5 or 406/121.5/243.0, would be banned. That outcome would be so nonsensical that I have to assume that this wording was an FCC oversight that they'll soon amend/clarify, and that this implication was not what they intended. But then again, the FCC is a gang of arbitrary and authoritarian idiots, so you never know...

BTW, to be clear, I'm actually in favor of the transition to the 406 MHz ELTs (and by that I mean the tri-band ELTs), and will install one in my airplane regardless. But I favor it as a personal choice, not as a commandment from Big Brother. The way our government is forcing it on us is appalling, and as free people we should be outraged.
 
az_gila said:
...the FAR 91.207 REQUIRES a TSO C 91a ELT.
Click to expand...

For part 91 operations FAR 91.207 requires either an "approved personal type or an approved automatic type emergency locator transmitter".

Are there any "approved personal type ELTs"? I'd much rather remove my 121.5 ELT and get a PLB than spend $800+ on a 406 ELT.
 
The question is...

MTBehnke said:
For part 91 operations FAR 91.207 requires either an "approved personal type or an approved automatic type emergency locator transmitter".

Are there any "approved personal type ELTs"? I'd much rather remove my 121.5 ELT and get a PLB than spend $800+ on a 406 ELT.
Click to expand...

...whose approval?

My McMurdo PLB is approved by COSPAS --

http://www.cospas-sarsat.org/index.php?option=com_content&view=article&id=193&Itemid=208&lang=en#m

...but where is the FAA approval list?
 
How would you like to own a Brietling 121.5 ELT watch?

BTW...I use the 121.5 and have a spare unit as well just in case.......I carry a SPOT PLB and will not invest in any 406 ELT until I absoutelly be made to do it by the FAA.
 
mv031161 said:
How would you like to own a Brietling 121.5 ELT watch?
Click to expand...
No worries, they're exempt!

(h) prohibit the certification, manufacture, importation, sale, or continued use of 121.5 MHz emergency locator transmitters (ELTs) other than the Breitling Emergency Watch ELT.

Sale and use of the Breitling Emergency Watch as a 121.5 MHz radiobeacon is authorized by a waiver granted by the Wireless Telecommunications Bureau?s former Public Safety and Private Wireless Division. Although we are prohibiting any continued marketing or use of standard 121.5 MHz ELTs, we will permit the continued marketing and use of the Breitling Emergency Watch.
Click to expand...

Looks like they heard about the meeting. Too bad the FAA didn't check their mailbox. :rolleyes:
 
No doubt EAA and AOPA will continue to argue for 121.5 ELTs.

There is a better solution. Let the FCC be right. Lobby to change the FAR so Part 91 operations don't require an ELT. Keep the 406 optional, as it is now.

Points:

Straight 121.5's are already near useless.

Most of us are reacting to the "aircraft 406" price schedule, not the loss of 121.5.

Times have changed. There are alternate ways to communicate our position or situation.

With no dual frequency requirement, 406 ELTs should become cheaper.
 
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Not too sure...

DanH said:
....
Straight 125.5's are already near useless.

...With no dual frequency requirement, 406 ELTs should become cheaper.
Click to expand...

The 121.5 are used for short range homing to a final crash site. Since the 406 bit only transmits for about 5 seconds in a minute, it's not as easy for homing.

The 121.5 bit is quite cheap, since it's a simple repeating "wail" with no coding.... I doubt if the 121.5 bit adds even $100 to the price at this present time, and is actually in the hand held PLB devices.

Certifying a G-switch is probably the expen$ive bit, along with a combined 121.5/406 antenna.

Note that a 121.5 device is also a 243 device, but the 243 frequency adds little cost since it is a direct harmonic...
 
I agree with Gil -- 121.5 still offers some usefulness for close-in homing, and also the fact that it can be picked up by any aircraft that happens to be "guarding" 121.5 whereas 406 can only be picked up by the sats. The 121.5 and 406 technologies differ in some significant ways, neither is perfect, and to a degree they complement each others' shortcomings.

I also agree with DanH that all these, and others, should be optional as far as regulations are concerned.

Anyway, whether 121.5, 243, and/or 406, the major costs for an ELT vendor are in development and certification, not parts. The actual electronic components are dirt cheap, likely cheaper even than the packaging. Parts cost is not what drives the retail price of an ELT unit, so for vendors that already have developed/certified it there is no major economic benefit on the device side for doing away with the 121.5 capability.
 
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I may have the wrong idea about current policy, so riddle me this....

You're flying along listening to 121.5 like a good citizen. You hear an ELT. Who will you tell about it, and more important, what will they do about it?
 
DanH said:
I may have the wrong idea about current policy, so riddle me this....

You're flying along listening to 121.5 like a good citizen. You hear an ELT. Who will you tell about it, and more important, what will they do about it?
Click to expand...

ATC or flight watch, were it me.

Watching this issue with interest since, depending on the resolution of the issue, I'll need to buy some equipment soon.
 
My 406 MHz PLB transmits my GPS position so homing may be irrelevant.

I will not be buying "equipment" soon.
 
It's 100 metres...

Ron Lee said:
My 406 MHz PLB transmits my GPS position so homing may be irrelevant.

I will not be buying "equipment" soon.
Click to expand...

...with the GPS, however I can't find out what happens if the GPS signal is an external source as some (most?) of the aircraft ELT versions are.

If you loose your avionics GPS signal before an accident, does it just keep transmitting the last GPS signal it received, even if the crash occurs later?
 
Ron Lee said:
My 406 MHz PLB transmits my GPS position so homing may be irrelevant.

I will not be buying "equipment" soon.
Click to expand...

I'm not losing any sleep over it. I need to buy something before first flight, but I have a few months to go. Hopefully the various agencies and alphabet groups will have the regulatory disparities sorted out by then.
 
az_gila said:
...with the GPS, however I can't find out what happens if the GPS signal is an external source as some (most?) of the aircraft ELT versions are.

If you loose your avionics GPS signal before an accident, does it just keep transmitting the last GPS signal it received, even if the crash occurs later?
Click to expand...

Excellent question. Does the 406 MHz ELT receive signals all during flight? If so, this may require power that drains the battery. If not, then once activated and waiting for a GPS position from the external source, there may not be a signal to provide because the crash destroyed the GPS receiver, power delivery to the ELT, etc.

My PLB has to be manually activated. Assumption is that I would activate it while airborne so it would have time to provide at least one usable signal with position before I contact terra firma. This may be unrealistic in some cases but since I have zero confidence in my 121.5 MHz ELT, I live with that possibility.
 
GPS and power to 406 MHz ELT

Ron Lee said:
Excellent question. Does the 406 MHz ELT receive signals all during flight? If so, this may require power that drains the battery. If not, then once activated and waiting for a GPS position from the external source, there may not be a signal to provide because the crash destroyed the GPS receiver, power delivery to the ELT, etc.
Click to expand...

The following is true of the Artex 406MHz ELT. Not sure if others operate the same way, but I would guess the same or similar.

In flight, the ELT gets an updated GPS position about every 2 seconds. If activated, the ELT will transmit the last GPS position received prior to activation, which should therefore have been within 2 seconds of impact and therefore very close to the impact site. Note: if loss of GPS occurred before impact, then the ELT will only transmit a GPS position if it was received less than 60 seconds before impact. Otherwise, it'll be considered too stale and no GPS position will be sent.

Updating the GPS position of the ELT in flight does of course require a little bit of power. But ship's power is used for this function, not the ELT battery. So no issue as far as draining the ELT battery. But it does mean that if you intend to kill the master switch before impact, then you should do so as late as practical so that the last GPS position received by the ELT will be as close as possible to the point of impact.

--

Some interesting position accuracy comparisons:
  • The old 121.5 / 243 MHz: 20 km radius, or 1260 km^2 search area
  • 406 MHz without GPS: 3 km radius, or 28 km^2 search area
  • 406 MHz with GPS: 100 m radius, or 0.031 km^2 search area

All of this assumes of course that the device activates and everything basically works correctly. How often that actually happens is a different issue. But if it does, you can see how dramatic the difference in the search area can be. And that translates to faster, more efficient, and more efficacious search and rescue.
 
That is some really interesting info Roee - I hadn't read how the GOS data gets t the 406 ELT's before. I can think of a number of scenarios in which the searchers could easily be looking for you in the wrong place if the position data is stale, or not being sent - a 3 km radius in wooded, mountainous terrain is a pretty big area to search for a tiny airplane!

I admit to being a bit of a fatalist when it comes to ELT's - I have one because it is required. Meanwhile, I have a GPS-equipped PLB on my harness - my emergency checklists all have activating it as the first step if I think I am going down somewhere. Assuming it survives the impact and isn't buried, it will keep putting out good GPS data from the crash site.
 
Update from the Aircraft Electronics Association website: http://www.aea.net/governmentaffairs...item.asp?ID=43

The August date listed in the AEA Regulatory Update June 21, is the absolute earliest date the FCC rule could have become effective. Thanks to the efforts of the AOPA, the AEA and other trade associations, the final rule has not been submitted to the Federal Register for publication; therefore, the 60-day clock for implementation of the rule has not begun. As such, at this time, there is no way of knowing if or when this rule will become final.

The FCC has clarified that the rule is targeting legacy TSO C91a type ELTs, which operate primarily on 121.5 MHz, not the general use of frequency 121.5 MHz as the rule implies. Current TSO C126 ELTs are not affected by this ruling.

While the AEA encourages its membership not to sell C91a ELTs to customers without them knowing the latest ruling of the FCC, there is no immediate regulatory need for operators to upgrade their legacy C91a ELTs to the more modern C126 ELTs. For safety reasons, the AEA continues to encourage operators to upgrade their ELTs to the modern C126 ELT. Operators of the legacy C91a ELTs should be made aware the usefulness of their ELTs is very limited, as the justification for the FCC ruling indicates, and most likely will not provide the search-and-rescue capabilities they might expect.
 
Great thread!

As I'm one of the fellas who ends up looking for the source of ELT transmissions I've run down a couple and a couple EPIRB's (ELT's for boats) I'd like to complement the contributors to this thread that have dispelled multiple misconceptions about 121.5 vs 406 beacons... I hope to not take this too far off topic, but I'd like to share one man's perspective... a man who gets woke up in the middle of the night to go find you when your ELT goes off... (I'm in the USCG)

Although COPAS/SARSAT may no longer monitor 121.5/243, that doesn't mean all the other aircraft out there are not monitoring 121.5/243. I only turn on my Direction Finding (DF) equipment when I'm looking for a beacon, but I always monitor atleast one guard freq if not both.

I commonly report ELT's going off to Center/Approach/FSS while on routine trainers and patrols. Seeing my aircraft is equiped with DF equipment, I'll atleast tune up the beacon and pass along my location and a line of bearing... frequently when I'm not tasked with something crucial, I'll fly the line of bearing myself and see where I get needle swing to help isolate the source. Most turn out to be small airports/millitary bases.

Of note, if the ELT turns out to be over land the mission belongs to the USAF/CAP and the FAA will pass it to them or the USCG depending on where the hit is suspected to come from... That said, just because its over land won't stop us USCG from pitching in!

Just recently a light civil with only a 121.5 ELT went down well inland North of Mobile AL. A USCG helo was flying a training mission and heard the beacon on guard, they turned on their DF equipment and flew the line of bearing to find the crash site. The crew landed, picked up the pilot and called for an abulance and flew him to were it was awaiting... All without COPAS/SARSAT.

406's don't transmit continually (like some have pointed out earlier)... so if you get one, I'd recommend getting it with the GPS funtionality. Unfortunately due to software erros my DF equipment won't display the GPS lat/long, but the COPAS system will pass it to the USCG... so it will make it to me via radio... atleast until we get a software upgrade...

Anyways when a GPS equiped beacon goes off, anytime day or night, we fly to the GPS location and typicaly effect much quicker rescues. As others have said the 406's don't DF as well as 121.5/243 due to there short burst transmission time... though some have low powered 121.5 beacons paired with them (usually an EPIRB)...

When all we have is 406 without GPS, we tend to fly the best 406 DF we can get from COPAS/SARSAT. On the way there we turn on our DF gear looking to lock on the 406. If we hear a beacon on guard (243/121.5) we swap the DF to 243/121.5 to home in as it gives us a consistant point...

On 406's without 121.5 beacons, i've had folks give me long counts on a handheld radio and DF'd that because its just plain better than the simple 406 to DF...

For those of you with short attention spans: if you get a 406 do your self a favor and get the GPS encoding it could shave hours to even days off our search for you.

.02 USD

Tom
 
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roee said:
... But it does mean that if you intend to kill the master switch before impact, then you should do so as late as practical so that the last GPS position received by the ELT will be as close as possible to the point of impact...
Click to expand...
If you are going to kill your master, it would seem that you would have time to turn on your ELT before impact. Thus transmitting your lat/long as you go down.

Based on what I have read, the real problem is that a good number of ELTs never trigger on impact, thus turning them on before impact might be a good thing.
 
Tom, thanks for the perspective.

Set aside the very lucky soul who happened to have his 121.5 ELT heard by a USCG helo on a training flight. Instead let's assume an ordinary Joe Pilot hears a 121.5 ELT and calls it in. What will happen?

http://www.sarsat.noaa.gov/406vs121.pdf

High false alert rate makes first-alert launch unfeasible.
Absent independent distress information means RCCs must wait for
additional alert information.
 
DanH said:
Tom, thanks for the perspective.

Set aside the very lucky soul who happened to have his 121.5 ELT heard by a USCG helo on a training flight. Instead let's assume an ordinary Joe Pilot hears a 121.5 ELT and calls it in. What will happen?

http://www.sarsat.noaa.gov/406vs121.pdf

High false alert rate makes first-alert launch unfeasible.
Absent independent distress information means RCCs must wait for
additional alert information.
Click to expand...

I'll assume you mean that Joe Pilot notifies Approach/center/FSS of hearing a 121.5 beacon... i can't speak for the FAA... but I understand they have the ability to DF 121.5... so if its over land I understand that it is passed to the USAF & CAP.... we get the ones over the oceans, coastal waters, and close to our bases.

That said while flying routine stuff I have been advised by approach that they've had reports of 121.5 beacons going off in a certain area, and I've 'lent a hand' by flying over that way and tuned up my df gear and given them a line of bearing to it from my location... typically with my bearing and theirs the beacons can be identified as coming from airports and the airport manager was given a ring. If over land the USAF takes over.

In the USCG I haven't been launched on solely a 121.5 going off.. there usuall has to be correlating data before we launch... ie a missing plane, an associated mayday call... etc other sorces DF'ing it away from an airport etc. Most ships have EPIRBS (406 ELT's for boats)... I've flown a few of them... one was an actual tug that went down so fast that 1 of the four crew was trapped and didn't make it off... the survivors didn't get a mayday off as they had to get off the tug so fast... the EPIRB was all that alerted us and helped us find them.... why?

A beautiful thing about 406's is that most of them transmit an ID code with them, so we know who's in trouble. The info allows us to quickly determine the validity of the hit (ie the office running the search can call the owner and determine if its a for real emergency or just a false alarm prior to launching assests)... That said i have been woken up to launch on just one hit of a 406 that didn't transmit an associated ID and only gave a poor line of bearing off a satelite... we flew a huge search pattern all night to find nothing.

On another occassion while I was transiting to from Mobile to Clearwater i got tasked with running down a 406 without a data stream... we tracked it down to Tyndal AFB in Panama city... the beacon was going off continuously and as it was late in the evening I guess nobody at the AF base heard it... Ironically the DF'ed lat and long from the COPAS/SARSAT satelite had it about 10 miles further out to sea... I wouldn't trust my life to a406 without GPS (there can be huge errors in the DF'd position)

anyways, 121.5's have such high false alarm rates I have yet to get launched to fly on one without correlating info... if I'm in the air and not busy I'll probably run it down.

So again, its your life, but if it was me I'd get a 406 with GPS encoding and not worry about it. My USCG airplane has one, and all I have to do is flip one switch and I'm confident my mayday went out, has everyone moving, and has my exact lat and long encoded with it... it really doesn't get any better than that for us Search and Rescue guys. I wouldn't settle for less in my personal plane.

my .02 usd.

Tom
 
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