Wings Magazine

The 406 ELT Debate!

I knew that when I was writing my July/August column about the pending changes to the ELT world, that it would gather the storms of controversy.

August 13, 2008  By Rob Seaman

I knew that when I was writing my July/August column about the pending
changes to the ELT world, that it would gather the storms of

Please believe me too – I do not think I am always right about
something and happy to see the other side if presented. This is one
subject, however, that seems to getting folks really talking. As a case
in point – and while protecting the privacy of those involved – here
are some comments that I have received and some explanations and
further logic to the issue.

First a comment. By e-mail (always welcome, by the way) – the following note came thundering in the other day.

While sitting in the FBO at Trois Rivieres waiting for thunderstorms to
pass, I have been reading Rob Seaman's article in the July/August
edition of Wings. He seems to have absorbed the Transport Canada
kool-ade regarding 406 MHz ELTs very uncritically.


I am returning from a flying holiday in a Cessna 172 from Ottawa
Rockcliffe along the north shore of the St. Lawrence to Lourdes de
Blanc Sablon – an airport slightly beyond the end of the world – and
back. My family members and friends in Australia, Canada and the U.K.
were aware of my exact position (to within a few metres) every 10
minutes throughout the trip. Flight Services were not because they have
not supplied an e-mail address to receive messages from my SPOT
( ) messenger – they had to rely
instead on position reports by radio.

The 406 MHz ELT is simply a technological improvement on an antique
system: the concept of "send nothing until you crash and then possibly
transmit a signal if the ELT and antenna survive the crash."

We now have access to much better systems. The SPOT system is obviously
proprietary and Transport Canada could not rely on a foreign company
for search and rescue but the technology is really simple and reflects
someone thinking about the problem rather than simply updating the
technology. The SPOT transmits until you crash and then possibly
continues thereafter – much more logical than the ELT methodology!

In the short term, I would feel a lot more comfortable if Flight
Services provided an e-mail address to which SPOT messages could be
sent. There would obviously be a lot of e-mails but they could all be
deleted unread after, say, 24 hours. If, however, I were to go missing
on my next trip to Lourdes de Blanc Sablon, I would feel more
comfortable if those e-mails could be opened and my flight of path
examined. Even if the device didn't survive the crash, the area to be
searched would be tiny.

Chris Hobbs

In reply to this – and similar verbal comments that are popping around – here is the counterpoint.

There is and can be some agreement with some of what the above-noted
gentleman is offering. However, in the bigger picture one has to say
that comparing a non-certified Commercial off the shelf (COTS) product
like SPOT to the likes of an Aviation ELT is ridiculous. In point of
fact, while he ridicules Transport Canada and its acceptance of “old
technology”, he should remember that this “technology” has been
endorsed and mandated by the World Aviation authority, ICAO and several
other governments. As another aviation professional noted to me, “It's
just amazing how well all kinds of gadgets work when the going is good!

However these devices (the 406 Mhz ELT) are for emergencies (read
accidents); hence their name ELT! During an aircraft accident, all of
this loose stuff gets lost or destroyed in a heartbeat.

Another associate stated, “People have to remember that the move to
406Mhz from 121.5 allows a SAR satellite to pinpoint a location to
within three to six miles. In addition to this, the device can, by use
of a cockpit-mounted switch, be activated prior to a crash to start
alerting the satellite. Also, because the technology is more advanced
than the gentleman states, it will transmit latitude and longitude
coordinates that were last input into the ELT from GPS or FMS. That
would bring the accuracy to within 30 meters!” And we know that the 406Mhz ELT works. Recently during a maintenance
session at YYZ, an ELT was inadvertently set off in the hangar when a
Technician hit the switch accidentally. Because the FMS was running at
the time, it gave the ELT the aircraft position. Within an hour, the
GTAA was standing in the exact hangar bay saying that they received a
call from Search and Rescue in
Trenton saying that there was an ELT transmitting from the hangar. That's pretty good and fairly quick.

ELTs are certified devices that are not only regulated by governments
but also carry a maintenance requirement that must be done in
accordance with regulations. This ensures operability when they are
needed. There are many satellite tracking systems out there and yes
some affordable ones like SPOT for the aviation enthusiast. Most of the
aviation pilots and operations folks I have spoken with state
categorically their first choice would be a 406Mhz ELT with a GPS position input. The consensus is that they prefer
the odds of it surviving a crash with one of these to a COTS product.
As one avionics specialist offered, “Turning a product like SPOT into a
certified unit would raise its price 30 fold at least. Some of the
cheaper approved satellite tracking systems run about $15K installed.
Try mandating that to the Cessna 150 owner and they would scream blue

As for bashing Transport Canada (something that is fairly easy to do on
most occasions) another thing the first the SPOT user might like to
remember is this – Transport Canada (to their credit) did leave the
door open in their rulemaking to any new technology that could do the
job as good as or better than the conventional ELT. However, that is
their minimum criteria – and rightly so. There are no such new (newer)
technologies on the market today that are suitable for the GA fleet
operating in a country as massive as Canada. So as intelligent as this individual may be, his judgment is clouded. It may be clouded by the fact he hates being mandated to do
something, and he certainly believes that he has better technology at

In general, we find that such attitudes are precisely why certain
things need to be mandated and equipage and maintenance rules are
thrust on the public because in the absence of mandated equipage for
such safety equipment – designed to perform a specific function in an
emergency – many (if not most) would opt either to have no safety
equipment at all, or to come up with some half-baked solution of their

There is no doubt that one day, affordable, approved Sat tracking
systems will be available and possibly integrated into the ATC system.
For today, there are ELTs, a satellite that monitors the frequency and
the good folks at Search and Rescue. Search and Rescue is a very
serious business. The UHF ELT is their new tool of choice. The VHF ELT,
despite its shortcomings, has been around for a long time. The UHF ELT
does in fact represent a significant technological leap forward. And until somebody comes up with a better
system that actually meets all the requirements, this will be the new
weapon of choice.

One other parting thought –  VHF ELT monitoring will be discontinued by
COSPAS on Feb 1/09. The real-world level-of-safety provided by a VHF
ELT after that date is basically….well…. zero! As an old TV ad used
to say – “you can fight or switch!”


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