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messydeer
12-30-2011, 08:39 AM
I'm trying to locate my ELT mount in the Sonex I'm building. One place that comes to mind is on the shoulder harness bracket, about 4' behind the cockpit . Advantage is it may need no extra bracing and it's out of the way. Bad thing is it may be too far out of the way. If I need to activate it manually in case the remote switch fails, then this could be a deal breaker. I'm small enough to crawl back on top of the cross braces for annual checks, but I'd not like to do that with a hemo-pneumo post crash. I see most people have mounted them where they are more easily accessible.

Thanks,
Dan

WLIU
12-30-2011, 10:03 AM
Don't forget that you have to remove the ELT every year to test it.

Also, I have not looked at the Sonex, but how will putting that mass that far back in the tail affect your weight and balance? You might be surprised by the result when you do the math.

I assume that you know that an ELT is designed to be mounted aligned with the direction of the expected crash impact forces and that the mounting bracket should implement that design factor. For fixed wing airplane ELT's, many of them need to be aligned fore and aft. The better airplane ELT's and helicopter ELT's are designed to activate in response to crash loads that may come from all axes.

Best of luck,

Wes
N78PS

messydeer
12-30-2011, 04:50 PM
Thanks, Wes.

I'd be able to crawl back there annually. It'd be about as hard as crawling under my car to change the oil, only cleaner. Wouldn't want to do it every day, but yearly wouldn't be a problem.

I think the mass aft of the CG won't be an issue, but that's a good point. Most people mount the ELT a couple feet further forward. I prolly have more weight added forward of the CG than design, so this place may even be better.

I plan to wear a PLB, or have it mounted someplace that can be accessed in flight. A McMurdo Fast Find 210 (no subscription) is only $200 at some internet outlets, $260 at ACS, but they'll match prices. I hadn't actually considered how having a PLB might influence where I might safely mount the ELT. From the little reading I've done about this, it seems the 121.5 ELT's have a dismal record of activating during a crash and since they aren't sat monitored, don't offer the best coverage, especially in out of the way places where they're really needed. So if I have a PLB, it wouldn't matter much where I mounted the ELT. And if I have survived a crash and need to activate the ELT, I'd certainly be able to activate the PLB, if I hadn't done so on the way down.

How does this train of logic sound to you?

Dan

WLIU
12-30-2011, 07:00 PM
Everyone's experience is different, so take mine with a grain of salt.

Relative to the population of aircraft and pilots, crashes are relatively rare and crashes out in the Tulees where no one hears the crunch are even rarer. I spent part of my flying career in antiques and junky skydiving ships and I buy into some wisdom handed down by one of my older peers - "crash near a telephone." And of the many crashes that I know of and that my peers rode through, the vast majority of guys who kept flying the airplane until the crunching noises stopped, climbed out of the remains and walked for help. Modern engines are stunningly reliable if you take care of them and the quality of your average homebuilt is equal to or better then what Cessna/Piper/Mooney is selling. And our airplanes are a lot more rugged than we usually think. So we install and maintain ELT's because we are mandated to, not because we get any utility out of them. I note that the CAP folks spend lots more hours looking for pot fields than looking for missing airplanes these days. But anyway...

So it sounds like you intend to purchase the minimum ELT to satisfy the regs and carry another device that you believe will be more effective in letting folks know where you are. A reasonable idea with a lot of options. That said, I will offer the suggestion that something like a SPOT, where your track is recorded all of the time will likely get folks to you faster than a manually activated unit. Plus my friends run their SPOT and then go home and pull up their track on their PC, with a map backdrop. They can show their friends and family where they wandered off to. Works for hiking, kayaking, as well as flying. So there is another dimension of utility to the device. Its not just dead weight 99.999% of the time. And if the track logging and the ability to e-mail greetings to your friends have value to you, they wind up being less expensive than a PLB in terms of value. And their built in GPS is as accurate as any other emergency locator.

I don't know how the consumer PLB's are supported by the emergency services folks. I seem to recall, and I may be wrong or have old info, that you have to register them or folks like the US Coast Guard won't respond to their signal. Yes? No?

Best of luck,

Wes
N78PS

messydeer
12-30-2011, 08:12 PM
Hmm...so are you saying I should crash near a pot field, Wes?

134813491350

Above are pics of my newly installed ACK E-01. Got it used for $100, complete with tray, straps, cables, remote, and antenna. This is about halfway back in the tailcone. I'll secure the antenna cable, which goes back one more turtle deck former (rib) and up to the top. Remote phone line cable will come forward to the remote which I'll prolly mount on the instrument panel.

messydeer
12-30-2011, 08:27 PM
Thanks for sharing your experience with SPOT. A few months ago I did some preliminary research in PLB's. I won't be buying for a few months more, closer to my plane going up for the first time, and will do more digging before I buy. I didn't like the idea of paying a yearly subscription to a device. Lots of them had this mandatory fee and I think SPOT was one of them. It may turn out that it's a better deal than a no frills, subscription free device like the McMurdo. I mentioned it cuz it was the cheapest without a subscription.

Below is a pic from the cockpit, showing the ELT ~3.5' back. For service, I'd slap a plank down the middle and shimmy back to the unit.

1351

Bill Greenwood
12-30-2011, 10:14 PM
I have worked some with air rescue here in Aspen, which was founded by Betty Pfister, a great lady, former WASP pilot who owned the P-39 that is now in Smithsonian museum. I have also done some lectures on mountain flying at EAA.
ELTs, for all their problems, have saved a number of lives in crashes. One incident, a man rented a Piper Lance in Dallas and flew his wife and kids up to Colo, crashing in bad weather in the mountains short of his destination. He had not filed a flight plan, so nobody knew to look for them. The only thing that saved his family was the ELT. As as matter of fact the plane had just had the annual the week before, and had a new ELT battery with full strenght.
Properly mounted they will activate in a crash. You don't have to manually activate anything, and you might not be physically able to. One problem can be that the anntena can break off in the crash and if so you don't get much range.
If you fly around somewhere like Florida, maybe you don't need an ELT that much. But if you fly in wilder country or less mild weather it might be good to have.
And do file a flght plan before taking your wife and kids off into the wilderness, so someone will come looking for you if you don't arrive.Watching your family freeze or starve to death would be awful.
As for as "guys climbing out of the airplane and walking for help", that might be true if you are flying near Osh in the summer time, but it is nonsense if you are in much of the west in winter, or in many places in the summer.
As for engines being reliable, maybe so, but that is not the main cause of crahes anyway; which for most light gen av is weather.

Mike M
12-31-2011, 07:46 AM
...the main cause of crashes anyway; which for most light gen av is weather.

with tongue firmly in cheek, i submit that weather never caused a crash. pilots operating in weather for which they, or their aircraft, or both, were unprepared is what causes crashes.

some people might find this an alternative to SPOT:

http://www.appleinsider.com/articles/11/09/07/chilean_airplane_crash_located_via_apples_find_my_ iphone.html

your mileage may vary.

Cary
01-05-2012, 06:56 PM
I had an Artex 406 ELT installed in my hot rod 172 as soon as they became available, several years ago. I also carry an ARC ResQLink 406 PLB (just bought last summer at OSH). I like flying in the Colorado and Wyoming mountains, and realistically I know things happen, as I've had one total engine failure with my current airplane and was able to land in a decent field. While I fully expect to survive any crash, and I really enjoy camping, I don't want to have to camp a long time while the CAP/SAR folk are looking for me. I want to give them as much help as possible, so using a 406 ELT and a 406 PLB narrows their search field.

Incidentally, registration of all 406 devices is mandatory, not because CAP/SAR folk won't look for you, because they will. But it will make it easier for them to locate you, and that way they can communicate with your family who may assist them. Registration is free and must be updated every 2 years--and it can be easily done on-line. With the info that you provide for your ELT, they know what your aircraft looks like, where you live, who to contact, your cell phone number, etc., all useful for trying to narrow down a search. The 406 PLB only lacks the aircraft info.

Cary

Jim Herd
01-06-2012, 05:50 PM
ELTs (121.5 & 406) have certainlyt saved lives, but they have failed to do so far more often than they have succeeded! There is limited data available, but it shows ELTs fail to call the cavalry in your hour of need - about 70% of the time! Even greater failure rate by some reports. Why? Simply because when you and your plane are in serious distres, so is your ELT. Yes, they have been beefed up in recent years, but the end result is not markedly different. The one area of great improvement is with false alarms - if/when they succeed in raising the alarm (whether bona fide or in error) the 406 units provide user information (if they have been registered) such that a phone call can often avoid a false alarm scramble for the SAR folks. That's great, but it doesn't do anything for safety.

As has been mentioned, SPOT is a serious alternative option, but it is not aviation oriented and leaves a lot to be desired. "Spidertracks" is a similar concept but designed specifically for G.A. With both units, the concept is near-real-time breadcrumb tracking, which is reported by sattelite to a web site for viewing by wheoever the owner authorizes. So with this concept the unit doesn't have to survive a serious crach to raise the alarm - the absence of the ongoing breadcrumb track pinpoints the crash site, within seconds. This technology is now mandatoy for all Alaskan state aviation operations. It is vastly better than ELT!

If you have a choice, forget about investing in a shiny new 406 ELT and look into Spidertracks. And no, I have no personal gain involved here. http://www.spidertracks.com/

Cary
01-08-2012, 10:34 AM
On the other hand, correct me if I'm wrong, but I believe that neither Spot nor Spidertracks is monitored except by whomever you designate--and what if you have no one doing that? Or what if the someone you have designated is less than curious about your trip progress? Or they're busy doing something else? I can imagine the conversation. "Mom, how's Dad's trip going?" "I don't know--here, let me check the computer. Oh gosh, it says that he stopped somewhere in western Utah. I wonder why he's there? That was this morning. I wonder why he hasn't called? Well, we'll check on him again in the morning." The point is that nothing calls "designee's" attention to the trip stopping, other than the end of the bread crumbs, and why it stopped is anyone's guess, unless the user can send a message to "designee".

The, of course, "designee" has to know who to call--and how many of us have given "designee" that information? Or for that matter, do we know, ourselves? You can bet that the average 911 operator doesn't know.

Then there's the annual fees, in addition to the equipment cost, which are a turn-off for some: Spot is $100 per year, Spidertracks is minimum $120 plus a 10 cent charge per "position report".

On the other hand, a 406 ELT or PLB is a one-time purchase, and there are no annual fees to use the SAR network, which is monitoring 24/7. For an extra $40/year, you can still send a message to Mom that you're OK through 406Link.

Cary

Jim Herd
01-10-2012, 11:38 PM
Here is the central difference between ELT and SPOT/Spider. ELT has a 30% chance of raising the alarm whereas SPOT/Spider has virtually 100% chance of leading SAR services to the scene of the accident or off-field incident.

Yes, if you don’t have your act together the satellite breadcrumb tracking devices might involve a long delay before the alarm is raised. As a practical matter, this is not the way it works. There is an escalating process for raising the alarm - and the user is entirely free to set up that system as they see fit. Generally speaking, most pilots set up a two-tier alerting system. The first alert goes to a few competent and interetsed family members, pilot friends, or your local FBO or dispatch office - and that alert includes calling cell phones, text messages, email messages, or whatever. If no formal alarm is raised within 15 minutes then the second tier alarm goes out automatically. This will usually be direct to the emergency services of your choice. With a little care by the user, it is inconceivable that the alarm won’t get out reasonably quickly. But the greater point is that there is almost 100% probability that the location will be known, instead of a 30% chance with ELT.

I must add that the new breadcrumb technology is not yet fully mature. There is room for improvmeent but it is already pretty sophisticated. For example, Spider has an instant alarm capability if the pilot presses a button in the air or if the position reports quit mid-flight - so no need for the observers to watch the flight every second on the website.

As for overall cost, well we all have to assess the value proposition as a matter of personal freedom. For most of us this will not be a deciding factor because ELTs carry hidden costs such as batteries and testing and antennas.

Just as with any other revolution, iterative improvements can be expected. But the point remains the same - breadcrumb tracking is a concept that is dramatically better than ELT if saving lives is our goal. I recommend that we all resist putting lipstick on that aged pig!