FCC Outlaws 121.5 MHz ELTs

[tsrup]

As predicted, AOPA released this today:
http://www.aopa.org/advocacy/articles/2010/100621elt.html

[West_Coast_Guy]

Huh?   

If you bought a new ELT in, say, 1998, what did you buy?

Well, I just dug a little deeper, and it appears that what 91.207 has prohibited since 1995 are TSO-C91 ELTs, but it doesn't say anything about ones that meet TSO-C91a, which are also 121.5 MHz. The following AOPA regulatory brief explains the difference between them:

http://www.aopa.org/whatsnew/regulatory/elt.html

It's hard to keep this stuff straight! 

[sardak]

Since 1995, C91a ELTs have been installed. They are 121.5/243.0 beacons and are still legal to install today. 406 MHz ELTs are built to TSO-C126, which can also be installed, and if the FCC order holds, will be required.

Mike

[sardak]

More evidence that the FCC, led by the National SAR Committee (among others), ambushed the aviation industry. From the Aircraft Electronics Association.
http://aea.net/governmentaffairs/regulatoryupdates.asp?ID=42

The AEA was made aware of this issue only today (June 21, 2010), and has begun working with the FAA, FCC and other associations to allow for a timely transition to this new FCC prohibition without grounding thousands of general aviation aircraft. At this time, the AEA recommends members delay selling any new 121.5 MHz ELTs until further understanding of this new prohibition can be understood and a realistic timeline for transition can be established.

Mike

I thought I posted this but it didn't show up. If we see this message twice, sorry.

[West_Coast_Guy]

I doubt that the inclusion of the 121.5 MHz beacon in a 406 MHz ELT makes it a 121.5 MHz ELT.

By the way, I've been having a hard time convincing some of the posters on the AOPA Forum of this. For some reason, some of them think that it's plausible that the FCC would intend to obsolete all of the existing 406 MHz ELTs along with the 121.5 MHz ones. Reading the explanatory text and notes in the Report and Order would seem to dispel that misconception, IMO.

[C-182 Jockey]

406 ELT Homer - If you read the Third Report and Order just after the paragraph on analog ELT's you will see another paragraph that talks about 406 ELT's.  The first line of that paragraph states that except for the "spurious emission limits specified" - the 406 - 406.1 ELT must meet the performance standards.

12. Section 87.199 is amended by revising paragraph (a) to read as follows:
§ 87.199 Special requirements for 406.0-406.1 MHz ELTs.
(a) 406.0-406.1 ELTs use G1D emission. Except for the spurious emission limits specified in
§ 87.139(h), 406.0–406.1 MHz ELTs must meet all the technical and performance standards contained in the
Radio Technical Commission for Aeronautics document titled Minimum Operational Performance
Standards 406 MHz Emergency Locator Transmitters (ELT)" Document No. RTCA/DO–204 dated
September 29, 1989.


12 Section 97.139(h) For ELTs operating on 121.500 MHz, 243.000 MHz and 406.0406.1 MHz the mean power of any emission must be attenuated below the mean power of the transmitter (pY) as follows: (1) When the frequency is moved from the assigned frequency by more than 50 percent up to and including 100 percent of the authorized bandwidth the attenuation must be at least 25 dB; (2) When the frequency is removed from the assigned frequency by more than 100 percent of the authorized bandwidth the attenuation must be at least 30 dB.


I would bet you a box of SM Doughnuts that is the allowance for the analog 121.5 homer on the 406 beacons.

Commies am I close??

[West_Coast_Guy]

Unfortunately RTCA/DO-204A (the current version) is only available for purchase (for around $100). However we can infer the spec by looking at the specs for available units. The first one I checked is five watts on 406 MHz, and 100 mW on 121.5 MHz. That's about 17 dB down.

http://www.aircraftspruce.com/catalog/avpages/elt406.php

[C-182 Jockey]

FCC Decision - Before you bash the FCC folks keep in mind that the FCC is a member of the National SAR Committee along with the FAA, USAF-AFRCC, USCG, NASA, FEMA, National Park Service, NOAA and the USGS.

The 121.5 phaseout discussion has been going on for almost 20 years!  No one was "blind sided".  The last time a public notice was issued was January 2009.  "The Commission has prohibited the use of 121.5 MHz EPIRBs on U.S.-registered vessels,  and is considering a proposal  to prohibit the use of 121.5 MHz ELTs on U.S.-registered aircraft."
http://www.uscg.mil/hq/cg5/cg534/EmergencyBeacons/FCC_Public_Notice_121.5_Jan09.doc

What has happened is that the agency that regulates General Aviation has dropped the ball.  No leadership, no ownership. Maybe now that they have a "SAR Office" that might change.

Also keep in mind that this is not a US GA issue - it is an international issue.
"The International COSPAS-SARSAT Program's mission is to protect life and property by providing accurate, timely, and reliable alert and location information from persons in distress to search and rescue authorities. Due to numerous signal reception problems, a high incidence of false alerts (over 97%), and a host of other limitations associated with the 121.5 and 243 MHz frequencies, the International COSPAS-SARSAT Program, with guidance from the United Nations, decided to terminate the processing of 121.5/243 MHz alerts by the COSPAS-SARSAT satellite system as of 1 February 2009.


Additionally it is in the FCC's mission too "to further the Commission's goals of accommodating new technologies, facilitating the efficient and effective use of the aeronautical spectrum, avoiding unnecessary regulation, and, above all, enhancing the safety of flight."

Analog ELT's are 1950's technology folks!  It is time to make the change and do less searching and more rescuing!!

[Major Lord]

406 ELT Homer - If you read the Third Report and Order just after the paragraph on analog ELT's you will see another paragraph that talks about 406 ELT's.  The first line of that paragraph states that except for the "spurious emission limits specified" - the 406 - 406.1 ELT must meet the performance standards.

12. Section 87.199 is amended by revising paragraph (a) to read as follows:
§ 87.199 Special requirements for 406.0-406.1 MHz ELTs.
(a) 406.0-406.1 ELTs use G1D emission. Except for the spurious emission limits specified in
§ 87.139(h), 406.0–406.1 MHz ELTs must meet all the technical and performance standards contained in the
Radio Technical Commission for Aeronautics document titled Minimum Operational Performance
Standards 406 MHz Emergency Locator Transmitters (ELT)" Document No. RTCA/DO–204 dated
September 29, 1989.


12 Section 97.139(h) For ELTs operating on 121.500 MHz, 243.000 MHz and 406.0406.1 MHz the mean power of any emission must be attenuated below the mean power of the transmitter (pY) as follows: (1) When the frequency is moved from the assigned frequency by more than 50 percent up to and including 100 percent of the authorized bandwidth the attenuation must be at least 25 dB; (2) When the frequency is removed from the assigned frequency by more than 100 percent of the authorized bandwidth the attenuation must be at least 30 dB.


I would bet you a box of SM Doughnuts that is the allowance for the analog 121.5 homer on the 406 beacons.

Commies am I close??

Who you call'n a commie?

Major Lord

[West_Coast_Guy]

Does anyone actually have a copy of RTCA/DO-204? I'm wondering if the 121.5 MHz homing beacon is required, or is it just an option?

The reason I ask is that this ELT doesn't seem to have one:

http://www.aircraftspruce.com/catalog/avpages/aircraftspruceelt.php

[sardak]

Yes, your example ELT has a 121.5 homing signal. Check the manufacturer's website  http://www.elt406.net/index.htm  The 121.5 information is in the owner's manual.

In answer to your real question, all 406 MHz beacons sold for use in the US must have the 121.5 homing signal. This is in the Code of Federal Regulations, not the RTCM and RTCA documents. Those just define the technical requirements.

47CFR87.199
(b) The 406.0–406.1 MHz ELT must contain as an integral part a homing beacon operating only on 121.500 MHz that meets all the requirements described in the RTCA Recommended Standards document described in paragraph (a) of this section. The 121.500 MHz homing beacon must have a continuous duty cycle that may be interrupted during the transmission of the 406.0–406.1 MHz signal only.

47CFR95.1402
(b) The 406 MHz PLB must contain, as an integral part, a homing beacon operating only on 121.500 MHz and meeting all requirements described in the RTCM Recommended Standards document described in paragraph (a) of this section. The 121.500 MHz homing beacon must have a continuous duty cycle that can be interrupted only during the transmission of the 406 MHz signal. The 406 MHz PLB shall transmit a unique identifier (Morse code ''P'') on the 121.500 MHz signals.

47CFR80.1061
(b) The 406.0–406.1 EPIRB must contain as an integral part a ''homing'' beacon operating only on 121.500 MHz that meets all the requirements described in the RTCM Recommended Standards document described in paragraph (a) of this section. The 121.500 MHz ''homing'' beacon must have a continuous duty cycle that may be interrupted during the transmission of the 406.0–406.1 MHz signal only.

Here are the output power specs of the 121.5 signal from the RTCA and RTCM documents, of which I do have copies.

ELT (RTCA Standard DO-204A)
50 mW to 400 mW (technically, per the document - EIRP shall not be less than -13 dBW or greater than -4 dBW)

PLB (RTCM Standard 11010.2)
25 mW to 100 mW (the technical requirement -  25 mW -0/+6dB PEIRP)

EPIRB (RTCM Standard 11000.2)
same as PLB

*************
I'm fully aware of who makes up NSARC, I'm on first name basis with some reps to it, and am well versed in the history of Sarsat, beacons and the phaseout.  The fact is, the FCC ruling caught the aviation industry, which follows the FAA, by surprise. The FAA, which has not wanted to fight with AOPA, has refused to mandate 406 beacons for general aviation. Some NSARC member agencies and the NTSB have been fighting with the FAA over this since the early 90's. The way to finally force the issue, now that 121.5 monitoring has ceased, was through the FCC.

As I said earlier, the Coast Guard, through the FCC, outlawed 121.5 EPIRBs, but boat owners were given almost four years to make the transition. This move by the FCC gives aircraft owners 60 days from publication (which hasn't happened yet) to replace their ELTs.  In an effort to get at the FAA, the aircraft owners, and to a lesser extent ELT manufacturers, have been caught in the middle.

*********************
And to everyone who thinks the FCC rule outlaws 406 beacons because they contain a 121.5 homer, get real. The whole point of the action is to force the use of 406 MHz beacons, with the 121.5 homer. They aren't considered "121.5 MHz ELTs." Granted, the FCC wording could be more specific.

Mike

[West_Coast_Guy]

THANK YOU - EXCELLENT INFORMATION!!!

[C-182 Jockey]

DITTO - We just need an "Ask SARDAK" tab on this board.

[sardak]

As expected, the FAA, through the NTIA, asked that the rules regarding 121.5 MHz ELTs not be changed.

http://www.aopa.org/advocacy/articles/2010/100720elt.html?WT.mc_id=ebrief

http://fjallfoss.fcc.gov/ecfs/comment/view?id=6015693487

Mike

[West_Coast_Guy]

Thanks for the update.

I don't understand why they want new installations of 121.5 MHz ELTs to still be allowed. It seems like phasing out their manufacture over a reasonable time period, and letting existing installations remain in use as long as they meet their original specs, would alleviate most of the financial burden.

[Short Field]

It is a lot cheaper to replace an existing 121.5 MHz ELT when the old one fails than have a 406 ELT installed.  If the price falls on the 406 ELTs, then you will see more people changing out their 121.1s for the 406s.

[West_Coast_Guy]

It is a lot cheaper to replace an existing 121.5 MHz ELT when the old one fails than have a 406 ELT installed.  If the price falls on the 406 ELTs, then you will see more people changing out their 121.1s for the 406s.

406 ELT prices have come down a lot, although one of the manufacturers I checked on aircraftspruce.com prices the 406 at $583 vs $160 for 121.5, so you're right, 121.5 is still a lot cheaper. As volume increases, they should come down more. Maybe they should allow continued manufacture, but allow installation only to replace an existing 121.5 ELT.

Another thing discouraging upgrades is that the cost of having the required wiring harness installed from the ELT to the panel is said to about double the cost of the upgrade. One thing that would encourage additional 406 installations would be to eliminate that requirement when upgrading existing airplanes. That would deal with about half of the cost objection, while preserving almost all of the benefit of having a 406 ELT.   

[billford1]

I'm trying to process this. No more dragging a Ground Team together to go off in the night and search for hours to get to an airport where an hour or two later the owner opens the plane up, turns the thing off then walks away with a sheepish grin on his face. I've heard this called a "Hanger Banger".  So in the future we'll go off and search for a human being who is lost. Maybe the ANG will invite us to go out and practice with them for an event where they could possibly be short a Helo and wouldn't mind having a Cessna flying around to support them. Besides they know the Civil Air Patrol all know where the good restaurants are.

[West_Coast_Guy]

That reminds me: When I was working as an electrical engineer, I noticed that the marketing guys knew where the good restaurants were!