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This letter was posted to the CAP-ES mailing list some time ago.   It questions the very roots of what we do.   If we are to competently accomplish our stated objectives, we need to be able to explain why we do what we do.   Interestingly, this letter was signed using a pseudonym.   Would you be able to answer these difficult questions?   Read on.

Why is CAP trying to train and equip for something it rarely does -- Ground Search and Rescue -- when existing organizations are better equipped and supported? Isn't this the mission and responsibility of Public Safety agencies?

Is this an appropriate activity for an "Air" Patrol, and couldn't its effort and resources be better spent on the its primary emergency service mission, Air Search and Location (including electronic search and the supporting intelligence activities)?

If some Members aren't happy in supporting the primary mission, wouldn't they be happier (and infinitely more useful) as volunteer members of Public Safety agencies whose primary responsibility is ground search and rescue and victim evacuation and transport?

Just wondering.
-- DrSarcap

There were many responses to these questions; here is mine.

As the dawn of the new millennium breaks, we enter upon a dynamic and challenging environment. When it comes to missing aircraft, very soon the ďsearchĒ will be all but gone in electronic Search and Rescue. Undoubtedly this is for the better. Our goal all along has been to save lives and aid the injured. Technology is allowing us to achieve that end more quickly and therefore more efficiently. The revolution upon which we are now embarking will change SAR as drastically as did the widespread use of the ELT.

If we are to remain viable as an Emergency Services organization, we must anticipate and prepare for this paradigm shift. Fortunately, many individuals have already begun to do so. Civil Air Patrol has been traditionally kept on the leading edge of technological advances. For examples, think of our vast nationwide packet network, CAPís early entrance to the world wide web, or the groundbreaking use of airborne slow scan television.

Operationally, however, Civil Air Patrol has been slower to adapt. The new 406.025 MHz ELT is steadily making its way in to service with little note from Civil Air Patrol. Indeed, all of aviation has been slow to adapt and apply this new technology. The advantages of 406 ELTs are documented. The average search radius of a 406 ELT is 2 Nautical Miles. When the ELT is coupled to a GPS (or LORAN) receiver, that radius is down to 0.05 NM! Additionally, each beacon has its own digital signature that can be used to track down the owner or tail number associated with an individual ELT. Imagine AFRCC calling you at home to tell you that your ELT had been activated! This system only works if owners register their beacons--it can already be foreseen that CAP will soon be chasing unregistered beacons. The 406 MHz EPIRB has been proven to work in the maritime EPIRB environment. General Aviation has been slower to accept 406 beacons, but the current wind seems to be blowing in the direction that 121.5 MHz ELTs will soon be a thing of the past.

The "new" 406 technology does not come without caveats. No one knows for certain how the coupled beacons will work in the harsh field conditions created during an aircraft accident. Todd Engleman of the CAP Emergency Services discussion group has already reported that the position indicating system can be significantly (40 miles) off. For the non-coupled beacons, satellite accuracy is said to be 2 NM. This increased accuracy is due to the beacon's higher transmit power. Instead of a continuous weak beacon for SARSAT to track, 406 beacons transmit a high power (5 watt) signal every minute or so (50 seconds). Practical use (to include the false-alarm rate) has been almost totally water-borne EPIRBs which, for the most part, will have a uniform radiation pattern (water is flat). We donít know if the satellite accuracy will be the same when on the land (meaning, in the mountains) but assuming it is, it should be noted that 406 ELTs only have a 25 milliwatt transmitter which SAR forces will use to home to the ELT. This means you should keep you L-Pers, ladies and gentlemen, because you'll need them to track the beacon's "homer." We should be concerned with the difference between the 406 ELTís 25 mW signal on 121.5 MHz versus the current nominal 600 mW for conventional ELTs. The non-coupled 406 ELT will vastly narrow the search, but CAP will still need to DF those last critical few miles.

This means that ground (DF) teams will become only more necessary! If the search is greatly shortened, then a singular ground team can be dispatched to the search area at the same time as an aircrew. When the aircrew pinpoints the objective, the ground team can quickly be vectored to the site and coordinate the evacuation. Additionally, if adverse weather prevents the launch of aircrews, a ground team has a much greater chance of locating the search objective autonomously. Increased accuracy of the ELT will give the ground team a better place from which to start DFing. Even a moderately trained ground team should be able to locate an ELT when starting from 2 NM away.

Since 406 ELTs can be individually registered, the number of false alarms will drastically decrease. Currently, the National Oceanic and Atmospheric Administration (NOAA, the agency that operates the weather GOES satellites that listen for 406 MHz beacons) reports that currently 13% of 406 signals are false alarms. That's one beacon in eight, but remember that the vast majority of those beacons are EPIRBs. We don't yet know what the ELT numbers will look like. Compare that figure to the the traditional 97% plus false alarm rate for 121.5 beacons. When we understand that an actual emergency 121.5 ELT signal is more like 1 in 1000, the 406 system is an almost incredible improvement. This, too, has far-reaching consequences for Civil Air Patrol. Gone are the days when teams deploy to hunt an ELT in a hanger. Although CAP will be activated less often, when we perform an electronic search there will nearly always be a distressed aircraft at the end of it. This calls for ever-increasing proficiency and professionalism from our search crews. Nondistress finds will be a scarce breed. Being called out means that, with reasonable certainty, you will rescue someone that day. Are you truly ready for this?

It is important to note that 406 beacons are only voluntarily registered. Considering past experience, it seems as though Civil Air Patrol almost never searches for the responsible pilot. Pilots who file a flight plans, carry survival gear, and change their ELT batteries faithfully tned to be the same pilots who decide to stay at home during marginal weather and not run their fuel tanks dry. This interesting coincidence will become more important with the promulgation of 406 ELTs in aviation. Even if the FAA were to mandate a phase-in of 406 ELTs, many of them will still not be registered. We can expect to chase unregistered 406 ELTs in hangers, on private fields, and in the wild country. False alarms will almost certainly increase with the increase in numbers of 406 beacons. They should be lower than on 121.5, but we'll still have plenty of them. The conclusion is, then, that while false alarms should be relatively rare, they will still occur.

In case you haven't heard, the National Oceanic and Atmospheric Administration, in conjunction with international aviation, maritime, and search and rescue organizations, will "turn off" SAR alerting on 121.5 MHz. This only means that they're only saying a 121.5 beacon will not be a primary reason for a full-out search. What is surprizing to many people is that this is essentially status quo! If you go out and kick the tail of your favorite 121.5 ELT equipped airplane, CAP isn't going to be called out on that ELT-only signal for quite some time. We're talking in the neighborhood of 5 or more hours. AFRCC is first going to ensure that the signal wasn't a one-timer. If it keeps showing up, then they begin a telephone search of airfield managers and air traffic control personnel. If the signal still isn't resolved, they run the rest of their checklist which mainly seems to involve waiting some more while monitoring the signal. Finally, they call the appropriate CAP wing. This explains why CAP usually gets the call around 11 p.m., because that's when all the airport managers have gone home! In other words, the discontinuation of processing 121.5 as a first alert means that this waiting game will stretch out even longer--until a flight plan goes unclosed or a relative notices that their loved ones haven't returned from their flight. This change is truly not a major departure from the current procedures in place.

Furthermore, the chances of the FAA requiring 406.025 MHz beacons anytime soon is slim. The original requirement for ELTs in aircraft was a knee-jerk reaction by Congress when one of its own members went missing in an Alaskan aircraft crash. The "aviation lobby" will not support 406 ELTs due to their added expense. The lobbies won't support anything that is going to cost the average general aviation pilot an extra $1000 or so for his or her airplane. To their credit, these same lobbies have done considerable good by pushing to keep the LORAN chains going, thereby keeping our receivers in most CAP aircraft operable, but they won't help SAR on 406 because of money.


The remainder of this editorial is under construction.

This page of the CAP Emergency Services Resourcesô website was last updated 07/02/2008

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