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Impressions of the Spot unit after a month

Louise Hose

Well Known Member
I?ve had a Spot for about a month now and the folks at Spot sent a request that I participate in an on-line survey. I did. It was multiple choice and I answered the best I could. But, to my frustration, they didn?t allow a ?comments? area. So, when I said I wasn?t sure that I would renew my subscription and that I was only moderately satisfied with the product, I couldn?t explain to them what my real issues are with the unit. I had to check one box from choices they determined. So, I'm posting here a more thorough review of the unit after about a month of use.

I've mostly been using the Spot to keep Paul informed on my RV commutes to/from work. I power it up and hit the "send message" key as soon as I open the canopy. Then, I do my pre-flight and taxi. Generally, at the end of the run-up (just before calling the tower at the controlled field), I turn the unit off (to stop the message send out mode), then turn it on and initiate the tracking mode for the flight. This procedure allows Paul to receive a positive message through his Blackberry that I am at the airport and pre-flighting, then he can track my progress. If he is not at the arrival end, I turn off the tracking mode, wait about a minute, then send another message. I proceed to unload the plane and either tie it down or push it into the hanger, then turn off the Spot. This procedure seems to work pretty well and last night I was greeted with a cold drink before leaving the cockpit.

So, using the Spot is working out BUT there are several things I would like to see different for aviation. The Spot is clearly designed for slower moving activities, like hiking, and I?m really looking forward to trying it out on hikes and while cycling. (Distractions like our wedding and Hurricane Ike have mostly pushed those activities aside during the last month.) I wish I had carried a unit when I trained to race road bicycles. It looks like a fabulous tool for the solo cyclist!

I might preface this RV-focused review by saying that I do not feel an expert on the unit, so please correct/advise me if I just haven't learned about some "hidden" features.

1. It is almost unforgivable to me that there is no way to distinguish between ?send message? and ?track? modes after initiation. Both do the simultaneous green light flash. Surely there is an easy software fix for this issue. Maybe "send message" could have a double-blink on the message/track light and "tracking" could have a single blink.

2. You just shouldn't have to turn the unit off to cancel the "send message" mode. Again, I would think there would be an easy software fix for this problem.

3. The unit absolutely does NOT "Take the search out of search and rescue" when dealing with RVs unless the pilot/passenger is able to get a 911 or Help message out successfully. The best that the tracking will do is show which radar track was yours before you went down. The radar records will provide more precise information on the location. My unit pretty faithfully sends out every 9-12 minutes. But, I cover about 35nm in that time. That kind of precision provides little, if any, effective help unless the plane was too low for radar returns for an extended time before going down. I would be much more sold on the Spot in an RV if I could set the send-out interval. Ten minutes is fine for driving a car to the relatives (it's really only a toy, IMHO, for that mission) and hiking. But, I would want the tracking more like every minute or two in an RV if I thought it would help in a search of a downed plane. Even for our "mission" of starting dinner or bringing out the beer, an interval more like 4-5 minutes would be more useful. To be fair, when you look at their web site and advertising, their original market was the Outdoors crowd, and we are trying to use it beyond that original scope.

4. This one might be my ineptness....I haven't found a way to erase old tracks from the website. Since most of my flights are commuting these days, the track back-and-forth is very cluttered. If we can't clean it up when we, the users, want to do so, then that should be "fixed". If we can, maybe there could be clearer instructions on the process. (Love to hear from someone who has figured out how.)

I?m enjoying the use of the unit, and it has proved handy, but I?m not really sold on it yet for aviation. I could always use the cell phone to let someone know when I depart and arrive, as I used to do. The tracking is sorta fun, but not precise enough to really provide much value. The Help feature would only be useful in the rare locations (these days) that the cell phone didn?t work and there was no other phone available where you landed. The 911 feature certainly could save your bacon, but I?m pretty sure that I would prefer a PLB with no subscription fee and NOAA behind it. We?ve paid for a year Spot subscription and will continue to use the unit for that time. Maybe some of these issue will be addressed by that time and make the value clearer. And, it?s likely that we will be able to get out hiking, cycling, and doing other activities where it seems more suited over the next year. If not, I?m just not sure I find enough value in an RV for the subscription cost.
 
Louise,
Go to MESSAGES page....... at the bottom you can clk "tell us what you think" then just paste your post there.............. I am with you on this!!!
 
4. This one might be my ineptness....I haven't found a way to erase old tracks from the website. Since most of my flights are commuting these days, the track back-and-forth is very cluttered. If we can't clean it up when we, the users, want to do so, then that should be "fixed". If we can, maybe there could be clearer instructions on the process. (Love to hear from someone who has figured out how.)

We currently use SPOT trackers for traffic flights up here in your old "swingin' single" haunts (DC). This exact issue was of immediate concern (as we do 2 or 3 flights per day per device over the same basic route) and we are told a user selectable 'declutter' mode for the tracks is expected shortly. What 'shortly' means in the programming world, I don't know . . .
 
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LOOK AT IT THIS WAY.......

I’ve had a Spot for about a month now and the folks at Spot sent a request that I participate in an on-line survey.


I've mostly been using the Spot to keep Paul informed on my RV commutes to/from work. I power it up and hit the "send message" key as soon as I open the canopy. Then, I do my pre-flight and taxi. Generally, at the end of the run-up (just before calling the tower at the controlled field), I turn the unit off (to stop the message send out mode), then turn it on and initiate the tracking mode for the flight. This procedure allows Paul to receive a positive message through his Blackberry that I am at the airport and pre-flighting, then he can track my progress. If he is not at the arrival end, I turn off the tracking mode, wait about a minute, then send another message. I proceed to unload the plane and either tie it down or push it into the hanger, then turn off the Spot. This procedure seems to work pretty well and last night I was greeted with a cold drink before leaving the cockpit.

So, using the Spot is working out BUT there are several things I would like to see different for aviation. The Spot is clearly designed for slower moving activities, like hiking, and I’m really looking forward to trying it out on hikes and while cycling. (Distractions like our wedding and Hurricane Ike have mostly pushed those activities aside during the last month.) I wish I had carried a unit when I trained to race road bicycles. It looks like a fabulous tool for the solo cyclist!

1. It is almost unforgivable to me that there is no way to distinguish between “send message” and “track” modes after initiation. Both do the simultaneous green light flash. Surely there is an easy software fix for this issue. Maybe "send message" could have a double-blink on the message/track light and "tracking" could have a single blink.

2. You just shouldn't have to turn the unit off to cancel the "send message" mode. Again, I would think there would be an easy software fix for this problem.

3. The unit absolutely does NOT "Take the search out of search and rescue" when dealing with RVs unless the pilot/passenger is able to get a 911 or Help message out successfully. The best that the tracking will do is show which radar track was yours before you went down. The radar records will provide more precise information on the location. My unit pretty faithfully sends out every 9-12 minutes. But, I cover about 35nm in that time. That kind of precision provides little, if any, effective help unless the plane was too low for radar returns for an extended time before going down.

Even for our "mission" of starting dinner or bringing out the beer, an interval more like 4-5 minutes would be more useful. To be fair, when you look at their web site and advertising, their original market was the Outdoors crowd, and we are trying to use it beyond that original scope.

4. This one might be my ineptness....I haven't found a way to erase old tracks from the website. Since most of my flights are commuting these days, the track back-and-forth is very cluttered. If we can't clean it up when we, the users, want to do so, then that should be "fixed". If we can, maybe there could be clearer instructions on the process. (Love to hear from someone who has figured out how.)

I’m enjoying the use of the unit, and it has proved handy, but I’m not really sold on it yet for aviation. I could always use the cell phone to let someone know when I depart and arrive, as I used to do. The tracking is sorta fun, but not precise enough to really provide much value. The Help feature would only be useful in the rare locations (these days) that the cell phone didn’t work and there was no other phone available where you landed. The 911 feature certainly could save your bacon, but I’m pretty sure that I would prefer a PLB with no subscription fee and NOAA behind it. We’ve paid for a year Spot subscription and will continue to use the unit for that time. Maybe some of these issue will be addressed by that time and make the value clearer. And, it’s likely that we will be able to get out hiking, cycling, and doing other activities where it seems more suited over the next year. If not, I’m just not sure I find enough value in an RV for the subscription cost.

Louise..........

The unit looks like it is built really tuff. I think that if you crashed, and the SPOT was still in good enough condition to transmit, there would be a signal sent every 10 minutes till it was shut off. In that case, they would know where you are within about five feet. Now that's worth it!

As far as the check in, you need to do it just like you are doing. The unit must be shut off to cancel the mode. You just have to remember what mode you are in.
Press once for check. It will send check only once.....
Press and hold till check light goes off and you are in tracking. It will send every 10 minutes.

To shut down and turn on again and send a OK takes 7 seconds. You can do that as you sit there and log your flight time. But try this, to get out of track mode, hold down check button till it turns red... release it, now you are ready to send an OK.

As far as clutter......... go to MESSAGES, in message history clk chk last 24 hours, then select what you want to see by clicking on the box to the left... then clk "show on map".

If you purchased the ACR, you would have spent $650.00. It would sit there and do nothing for it's entire battery life (unless you had a real emergency) and then you would need to send it in to get the battery replaced. $$$.

SPOT IS A GOOD THING! Let's just hope (and we expect) that they solve some issues that have surfaced. I also expect that they will drop the price to $99.00 per year for everything. That would sure help...........:D

P.S. Just think if your dad placed one of these in the trunk of the family car when you were a teenager..........:eek:
 
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I just got back from Costa Rica where we spent several days hiking in Rain Forrest and Volcano. Out of 5-6 days where we spent virtually the whole day out with the spot tracker on, we got no more than 20 of the tracking beacons delivered. I had the spot mounted with a clear view of the sky on the top of my backpack.

None of the check in messages were delivered.

If this device was intended for outdoors users, it misses the mark pretty badly. I have not done any hiking in the US since I got it, but I suspect the same poor service here.
 
I've had SPOT for about 3 months. I paid $150 for the unit and $100 for the message sending subscription only. The unit seems to work, but I can't get over the feeling of being screwed by SPOT. I paid $150 for the unit and then 2 months later they are giving them away, with no offers of upgrades, rebates, etc., nothing to existing customers. Everytime I look at SPOT I get depressed. I hate the feeling of being taken advantage of and I will not be renewing my subscription. I cannot support a company that does not support it's customers.

It's like buying a brand new shirt and finding a spot on it. ;)
 
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I totally agree with you Larry. Screwed again. Maybe I would feel better about if they would give us buyers a year free subscription to make up for it.
I'll bet they dont.
 
My Experience

I've had a lot better experience than many of these posts. I'm based in Kansas City and I fly great distances around the country with the SPOT: such as Dallas, Las Vegas, Atlanta, Oshkosh, Santa Fe, Tuscaloosa, Ft. Lauderdale, etc.

At first I had issues. It wouldn't seem to keep tracking when I sent an OK message, etc. But, now that I have figured out its idiosyncracies it seems to do fine for me across all these routes of flight. Mine reports every 10 minutes, based on the website maps.

My family is constantly telling me to stop sending the OK messages to their cell phones :D, while my co-workers get the email announcements so they can look up the lat/long on the map.

It's working fine for me.
 
good experience here

We also have had a good experience with our SPOT, once we figured out how to send the okay message, then turn on tracking, and then turn off tracking at out destination, and send another okay. Our kids and Mom can keep track of our travels without lots of cell phone calls. We like it.

Yesterday we fly up to Branson, Mo. Check out our track on the link in my signature line.
 
horizontal mounting helps

I experimented with having the SPOT clipped into my hooker harness vertically on a flight today and then had it mounted horizontally on my harnness at the top of my shoulder. I lost some signals with the unit vertical and the timing varied between tracks, but with the unit mounted horizontally, it was tracking every 10 minutes. So the position does seem to help on my RV-4. Will try to come up with a horizontal mounting bracket for it as the RV-4 doesnt have a dash to lay it on.

One thing I would like to see on the unit is after you send a check-in message it automatically goes to track mode instead of just staying on but not doing anything.
 
A "6" on the Cooper-Harper scale (applied to RVs)

As far as clutter......... go to MESSAGES, in message history clk chk last 24 hours, then select what you want to see by clicking on the box to the left... then clk "show on map".

Warren,
I'm not able to follow these instructions and would like to figure it out. Can you explain in a little more detail? How do you "click check last 24 hours"?

I agree that Spot is absolutely a good thing. It seems the main concern right now is that the potential customer understand its capacities and limitations. Discussions like this one are healthy in achieving that understanding.

Personally, I'm dubious about a Spot being positioned to send out messages after an unplanned landing where the pilot/passengers can not actively activate the unit (i.e., I agree that it's probably hardy enough but it would take luck to be appropriately positioned), and I give the PLB no higher expectations once a crash occurs. I've worked with GPS in the rain forest and other heavily vegetated areas and I certainly don't expect Spot or a PLB to send or receive messages in those environments except through luck or an extended antenna. I would want the 911 message out before landing using any such technology.

Paul and I were just talking about this issue and he raised the flight testing standardized rating system, Cooper-Harper (http://en.wikipedia.org/wiki/Cooper-Harper_rating_scale). I would rank the current status of the Spot for RV aviation at a "6" --- Very objectionable but tolerable deficiencies. If I was using it more for long cross-country flights, I might call it a "4" --- Minor but annoying deficiencies. I don't have enough experience in other activities, but I might give it stellar marks for hiking in New Mexico or cycling the Rockies.

Lastly, I really like Tom's recent suggestion of a mode that goes directly from "send" to "track". That would be exactly how I would use it for almost all cross-country trips!
 
Moderator Note:

Let's keep the thread productive, OK? This is a forum for us to share our experiences and our opinions. We all need to refrain from belittling the opinions of others.

Remember: Your Actual Mileage May Vary.
 
Warren,
I'm not able to follow these instructions and would like to figure it out. Can you explain in a little more detail? How do you "click check last 24 hours"?

Click on "MESSAGES" tab........ you should now be in "MESSAGE HISTORY". To the right of the blue "show on map" button, it says DATE RECEIVED. Set it for 24 hours......... or what you want to look at.

Now look at the message list and check in the box on the left under "select" what you want to see on the map. Or just click "SELECT ALL". Then click "SHOW ON MAP".
 
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Let's see the option on the public page

Thanks for the further information, Warren. I guess this is only available on the user (non-public) page? Since I already know where I was today, I was looking for that sort of option on the visitor's page. Something intuitive and easy for someone (other than Paul) to see my progress. Maybe a work colleague who is picking me up that particular day.

This concern should be particularly easy for the Spot folks to address.
 
Maybe so, but when I mentioned it to Customer Support, I was told there was no plans to change the web interface yet. I had asked for the ability to filter by date/time and to delete unwanted messages. I also wanted to be able to view all the messages that I filtered; I just took a long trip in a car and the messages were split across two pages.

Other than that, I like the SPOT. I, too, have a concern about the distance traveled between tracking signals. My idea is to press 911 if it looks like I'm going to have a forced landing but I'm not sure that I can guarantee to do that in an emergency situation. Still, having the Spot along increases the odds.
 
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My idea is to press Help if it looks like I'm going to have a forced landing but I'm not sure that I can guarantee to do that in an emergency situation. Still, having the Spot along increases the odds.

If you are going into a forced landing / emergency you'll need to push the "911" button. The "Help" button will only send an e-mail to those you have chosen to get the "Help" message, just like the "Okay" button.

I agree SPOT increases your chances, just don't rely on it.
 
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Thanks for the further information, Warren. I guess this is only available on the user (non-public) page? Since I already know where I was today, I was looking for that sort of option on the visitor's page. Something intuitive and easy for someone (other than Paul) to see my progress. Maybe a work colleague who is picking me up that particular day.

This concern should be particularly easy for the Spot folks to address.

My wife's computer at work, and another one in her home office, uses my password for SPOT. This makes all the options available on three different computers. We use the 24 hr., as well as "unchecking" previous SPOT transmissions on the same trip.

L.Adamson

The "Help" button will only send an e-mail to those you have chosen to get the "Help" message, just like the "Okay" button.

I agree SPOT increases your chances, just don't rely on it.

It will also send a "text" message with coordinates to cell phones that you select.

L.Adamson
 
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long trip yesterday

My spot worked well again yesterday as we made a flight from Branson, Mo to Nashua, NH with stops at Frankfort, Ky and Dubois, Pa. Worked well for us. Check out the link on my signature line. The SPOT worked well riding on top of the bags in the back of an RV7a.

A note about our trip. We climbed to 9500 feet out of Branson and picked up a slight tailwind, according to our GRT, of about 5 mph. Ran the IO360 at full throttle and 2400 rpm, leaned LOP to 7.2 gal/hr at 185 mph true at about 25mpg. Had a smooth ride over a scattered layer to Frankfort, Ky. After fuel, we climbed back up to 9500, same power setup, and got a better tailwind of 10-15mph. However, we had considerably more clouds, broken or overcast, but our destination of Dubois, Pa was good for a letdown. After a late lunch and fuel, we filed IFR to Nashua, NH because NY and NH were overcast. So we filed and climbed to 11000 for a direct IFR flight, leaned again LOP for 6.7 gal/hr. Ajpproach provided vectors as we let down through the overcast for a visual approach 20 min before sunset.

RV's are great traveling machines. We are enjoying the grand kids.
 
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SPOT GPS beware

I know many have used spot and are happy with it, but beware that customer service is a nightmare. Long long waits on hold for billing issues and no way to cancel an account online. DO NOT USE AN AUTO-RENEWAL CREDIT CARD. It's very difficult to terminate the service!

Also on a functional note there is no way of knowing if tracking continues while flying. I have done many long cross countries and there is often long gaps in tracking. ...yes it was in full view of the sky, but according to SPOT inc. some avionics interferewith its reception capabilities. Just beware of its limitations and extremely poor customer service.

:eek:

Don
RV7
 
A lengthier review on Spot

Interesting to know about the problems cancelling. That seems to be the rub on auto-renews with many companies.

As for my observations after more than a year of use, I think I will stick by everything I said in my original review. Works good for me and my uses and I renewed my subscription this year, but it has frustrating limitations.
 
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Just the opposite.....I'm very happy

I know many have used spot and are happy with it, but beware that customer service is a nightmare. Long long waits on hold for billing issues and no way to cancel an account online. DO NOT USE AN AUTO-RENEWAL CREDIT CARD. It's very difficult to terminate the service! Also on a functional note there is no way of knowing if tracking continues while flying. I have done many long cross countries and there is often long gaps in tracking. ...yes it was in full view of the sky, but according to SPOT inc. some avionics interferewith its reception capabilities. Just beware of its limitations and extremely poor customer service.

Let's just say................I'm more than thrilled with SPOT..

With one year of SPOT, it's done very well in sending out a position report every 10 minutes. We fly mostly cross countries, and check every flight when we get home; as well as some family members following along. I've never been disappointed. For reference, we just checked the last two cross-country flights. It never missed the 10 minute interval (within a few seconds).
Perhaps it is some avionics? Mine sit's on the rightside glareshield. Not that far from the XM radio antennas.

BTW---Following a two day cross country this weekend, my wife placed her headphones on the SPOT which activated the 911 button. Within a couple of minutes, the SPOT emergency assistance was on my cell phone. That's good service if you ask me! It's the reason we bought SPOT. SPOT does work! I wrote a seperate thread on this a few days ago.

L.Adamson ---- RV6A
 
GPS reception in the mountains

GPS reception in the mountains
I have done a good bit of backing in both the Rockies and the Appalachian mountains; inevitably some hiker will bring along a backpacker?s GPS only to find out in the tight valleys they don?t receive enough satellites to get a fix.

This has always made me wonder how the SPOT and the new ELTs will work. Even if they can triangulate their location, can they reach a satellite to report that location?

I would hope the answer is yes as people much smarter than I created these systems.
 
spot and aprs

While the spot unit has some excellent features, as mentioned the 10 minute interval covers alot of ground at 160 knts. Maybe as a supplement you could use a portable, or fixed aprs unit. I have been using a portable micro track in a selfcontained case and set it in the seat beside me making sure it has sight of the sattelites. It can be programed easily. I have mine set to update every three minutes or with any heading changes. Using both gives you the option of sending out a disterss signal if needed and better locating abilities of the aprs unit.
 
Important Variable = Satellite Link Margins

GPS reception in the mountains
I have done a good bit of backing in both the Rockies and the Appalachian mountains; inevitably some hiker will bring along a backpacker?s GPS only to find out in the tight valleys they don?t receive enough satellites to get a fix.

This has always made me wonder how the SPOT and the new ELTs will work. Even if they can triangulate their location, can they reach a satellite to report that location?

I would hope the answer is yes as people much smarter than I created these systems.

I've read through all the posts in this thread and had resolved not to respond, but the question quoted above is one which needs to be investigated if we're to have any ability to make a reasonable analysis of the relative merits of each SAR system - 406MHz ELT, PLB and SPOT.

The greatest performance differentiator between these systems is satellite link margin. In other words, how much excess power exists in the system, over and above the bare minimum required for the satellite to hear the distress message.

In the case of SPOT, the satellites it uses are the Globalstar constellation, and to be more specific, it uses the L-band service provided by these satellites (not the S-band service used by Globalstar's voice services). Link margins for this service are extremely thin - transmit power from SPOT is less than 1/4 watt. This simiply isn't enough juice to cut through any kind of clutter like trees or terrain. And because the link margins are so low, if the antenna doesn't point straight up your chances of getting a signal through are greatly reduced.

One other bit of info that often escapes evaluation is the type of relay that Globalstar satellites provide. They are effectively just a "bent pipe", ie they relay messages from your SPOT directly down to a Globalstar groundstation. Other constellations like Irridium relay messages from one satellite to another until it reaches a satellite that has a ground station in view. This difference in operation is very important because Globalstar groundstations are limited in their geographic location - don't try using SPOT above 68degrees latitude, nor over the oceans, nor over Africa. It just won't work because there are no groundstations in view.

By contrast, the satellites used by 406MHz ELT's and PLB's take two forms. (Remember, there are NO satellites listening on 121.5 - the last one splashed down in early Feb '09.) The most important SARSATs are likely the geostationary birds. Their footprint over the ground provides for very close to 100% monitoring coverage over the earth's surface. If your 406MHz ELT or PLB starts to transmit, those birds will be the first to hear it and will relay the message to a ground station. That message essentially says "I've heard a distress beacon, it's a valid signal, and it belongs to XYZ aircraft" - this is the basic "detection" function. The next satellites that come into play are 5 LEO, low-earth orbit birds. They circle the world listening for 406MHz signals and then use Doppler effect to calculate the position of the transmitting beacon - this provides the "location" function. By 2013 there will be MEO (mid-earth orbit) birds which will provide both detection and location functions.

Now what about 406MHz ELT satellite link margins? Well, they are, by design intent, extremely robust. Our new ELTs transmit a minimum of 5 watts of power. That's enough to push the signal through foliage, to bounce it off rocky canyon walls, etc. And there's enough margin built into the system that there's a high probability of the distress signal getting through, even if your airplane has flipped over and your antenna is no longer pointing skyward.

After reading through this info I hope we can see that, while flying, SPOT will likely work pretty darned well since we give it a clear, unobstructed view of the sky. Just remember to point the antenna up into the sky!. In the case of an "unplanned landing" (what a gentle euphemism for something that's normally anything but gentle!) SPOT has little to no spare horsepower to push a signal through foliage, or to overcome the "slight" tilt its antenna may receive upon impact. A 406MHz ELT, on the other hand, provides a robust signal which offers high probability of detection in a post-crash scenario.

Let's be honest - SPOT and ELTs are designed to do two different things. If you've got the cash in your personal budget to own and operate both systems then you'll have the convenience of communications offered by SPOT combined with automatic activiation and high probability of detection offered by a 406MHz ELT. Just like a belt and suspenders, redundancy in SAR alerting devices is always a good thing. But if you're only going to operate one system or the other, just remember that most "unplanned landings" don't give the operator much, if any, time to hit the 911 button, and SPOT will likely be of little to no use when your airplane is upside down under a shady conifer. Without doubt, the 406MHz ELT should be your default SAR alerting device.
 
great post

I've read through all the posts in this thread and had resolved not to respond, but the question quoted above is one which needs to be investigated if we're to have any ability to make a reasonable analysis of the relative merits of each SAR system - 406MHz ELT, PLB and SPOT.

The greatest performance differentiator between these systems is satellite link margin. In other words, how much excess power exists in the system, over and above the bare minimum required for the satellite to hear the distress message.

In the case of SPOT, the satellites it uses are the Globalstar constellation, and to be more specific, it uses the L-band service provided by these satellites (not the S-band service used by Globalstar's voice services). Link margins for this service are extremely thin - transmit power from SPOT is less than 1/4 watt. This simiply isn't enough juice to cut through any kind of clutter like trees or terrain. And because the link margins are so low, if the antenna doesn't point straight up your chances of getting a signal through are greatly reduced.

One other bit of info that often escapes evaluation is the type of relay that Globalstar satellites provide. They are effectively just a "bent pipe", ie they relay messages from your SPOT directly down to a Globalstar groundstation. Other constellations like Irridium relay messages from one satellite to another until it reaches a satellite that has a ground station in view. This difference in operation is very important because Globalstar groundstations are limited in their geographic location - don't try using SPOT above 68degrees latitude, nor over the oceans, nor over Africa. It just won't work because there are no groundstations in view.

By contrast, the satellites used by 406MHz ELT's and PLB's take two forms. (Remember, there are NO satellites listening on 121.5 - the last one splashed down in early Feb '09.) The most important SARSATs are likely the geostationary birds. Their footprint over the ground provides for very close to 100% monitoring coverage over the earth's surface. If your 406MHz ELT or PLB starts to transmit, those birds will be the first to hear it and will relay the message to a ground station. That message essentially says "I've heard a distress beacon, it's a valid signal, and it belongs to XYZ aircraft" - this is the basic "detection" function. The next satellites that come into play are 5 LEO, low-earth orbit birds. They circle the world listening for 406MHz signals and then use Doppler effect to calculate the position of the transmitting beacon - this provides the "location" function. By 2013 there will be MEO (mid-earth orbit) birds which will provide both detection and location functions.

Now what about 406MHz ELT satellite link margins? Well, they are, by design intent, extremely robust. Our new ELTs transmit a minimum of 5 watts of power. That's enough to push the signal through foliage, to bounce it off rocky canyon walls, etc. And there's enough margin built into the system that there's a high probability of the distress signal getting through, even if your airplane has flipped over and your antenna is no longer pointing skyward.

After reading through this info I hope we can see that, while flying, SPOT will likely work pretty darned well since we give it a clear, unobstructed view of the sky. Just remember to point the antenna up into the sky!. In the case of an "unplanned landing" (what a gentle euphemism for something that's normally anything but gentle!) SPOT has little to no spare horsepower to push a signal through foliage, or to overcome the "slight" tilt its antenna may receive upon impact. A 406MHz ELT, on the other hand, provides a robust signal which offers high probability of detection in a post-crash scenario.

Let's be honest - SPOT and ELTs are designed to do two different things. If you've got the cash in your personal budget to own and operate both systems then you'll have the convenience of communications offered by SPOT combined with automatic activiation and high probability of detection offered by a 406MHz ELT. Just like a belt and suspenders, redundancy in SAR alerting devices is always a good thing. But if you're only going to operate one system or the other, just remember that most "unplanned landings" don't give the operator much, if any, time to hit the 911 button, and SPOT will likely be of little to no use when your airplane is upside down under a shady conifer. Without doubt, the 406MHz ELT should be your default SAR alerting device.

Thanks for posting this description. Best breakdown of the systems involved I've read yet, and very useful for understanding how they work.

Personally, I haven't decided whether the 406 ELTs are worth the $1k, but definitely think carrying a SPOT increases safety. Part of my forced landing checklist includes hitting the 911 button on the SPOT.
 
instructions

I would like to see basic instructions and definitions for the light patterns molded into the case cause I use mine so infrequent that I'm unsure how to correctly operate/interpret with 100% certainty.

Bevan
 
I would like to see basic instructions and definitions for the light patterns molded into the case cause I use mine so infrequent that I'm unsure how to correctly operate/interpret with 100% certainty.

Bevan

I placed a label on the back that says .... TRACK PRESS OK FOR 5 SEC. That and the sticker that's on the back already is all I have needed.......:eek:
 
APRS vs. SPOT?

I have read this thread with interest since I did use a borrowed SPOT when I landed at all of the public use airports in South Carolina on July 4th of last year. I have since installed an APRS transmitter in my RV-8. I would be interested in comparrisons of the two systems by others who have experience with both.

IMHO the APRS is just what I want in a tracking system. The initial cost was less than $200. No subscription fee. Position reports every minute (less when turning). Accurate postion, speed and altitude reporting. Track can be viewed by anyone with internet access. No hassle operation: just turn on the master switch and its tracking. I have used the APRS all over the US and find that it even tracks in mountainous terrain if you aren't deep in the valleys. While it will not send a 911 message, if I go down I am reasonably certain that my last position will be reported within one minute of impact.

BTW, I have clicked on the "track me" link on several SPOT user's posts and have yet to see a currrent track. What gives? Click on my "track me" link and you can see my last flight or select any date since I installed the APRS to see where I went on that day.

I know SPOT has some features that APRS does not, but I think anyone considering purchase of any SPOT, APRS, 406 ELT should weigh the benefits of each and make an informed purchase. In my case, APRS won.
 
I know SPOT has some features that APRS does not, but I think anyone considering purchase of any SPOT, APRS, 406 ELT should weigh the benefits of each and make an informed purchase. In my case, APRS won.

I'm just not into a ham license, finding a place for an antenna, etc. I turn the SPOT buttons on, place on the glareshield, and turn it off after landing. Has never failed in mountainous areas (nearly all my flying is in mountainous areas), and we know that help is on the way within two minutes of hitting that 911 button......... from experience. Yet, all three methods certainly do have advantages over the other.

Note: for those that don't know, my wife placed here headphones on the SPOT after landing & taxiing up to the hangar. This activated the 911 feature, and I got a cell call within two minutes.

L.Adamson ---- RV6A
 
I have read this thread with interest since I did use a borrowed SPOT when I landed at all of the public use airports in South Carolina on July 4th of last year. I have since installed an APRS transmitter in my RV-8. I would be interested in comparrisons of the two systems by others who have experience with both.

IMHO the APRS is just what I want in a tracking system. The initial cost was less than $200. No subscription fee. Position reports every minute (less when turning). Accurate postion, speed and altitude reporting. Track can be viewed by anyone with internet access. No hassle operation: just turn on the master switch and its tracking. I have used the APRS all over the US and find that it even tracks in mountainous terrain if you aren't deep in the valleys. While it will not send a 911 message, if I go down I am reasonably certain that my last position will be reported within one minute of impact.

BTW, I have clicked on the "track me" link on several SPOT user's posts and have yet to see a currrent track. What gives? Click on my "track me" link and you can see my last flight or select any date since I installed the APRS to see where I went on that day.

I know SPOT has some features that APRS does not, but I think anyone considering purchase of any SPOT, APRS, 406 ELT should weigh the benefits of each and make an informed purchase. In my case, APRS won.

Excellent report, Smokey, and a fine datapoint for those of us interested in APRS coverage nationwide.

In case someone is reading this thread and isn't familiar with APRS, we have a dedicated forum on this site:

http://www.vansairforce.com/community/forumdisplay.php?f=104

There are stickies and threads on the forum that will answer most of the questions anyone would have.

The Tech ham license is very easy to obtain and shouldn't discourage anyone from getting involved in APRS. The equipment is inexpensive, easy to install, has great support, cost nothing to use..........and works great.

Anyone interested in APRS is encouraged to ask any questions on the APRS forum. "Pete the Geek" Howell (the father of RV APRS) or other experienced users will promptly fill in the gaps for you.
 
BTW, I have clicked on the "track me" link on several SPOT user's posts and have yet to see a currrent track. What gives? Click on my "track me" link and you can see my last flight or select any date since I installed the APRS to see where I went on that day.

I know SPOT has some features that APRS does not, but I think anyone considering purchase of any SPOT, APRS, 406 ELT should weigh the benefits of each and make an informed purchase. In my case, APRS won.

Smokey,

I have a SPOT and am installing an APRS now. I'll let the SPOT tracking subscription run the rest of this cycle, and will have the chance to do some side-by-side testing...and will report back on it. Then I'll probably go to the lower cost version of SPOT for the OK/HELP/911 features, and use APRS as my exclusive tracker. Concur with you that the APRS tracking feature wins the race among real-time trackers (APRS/SPOT/iPhone Tracklog are the ones I've seen tested).

As for the link to SPOT tracks: the URL that gets sent to those you send an OK message to is strictly a map of the one SPOT hit where the OK button was pressed. It doesn't update or move. To get to a user's live track, you need to know the link to that user's "SPOT Shared Page". I tried to put mine in my OK message, but it is too long. So for those that I want to be able to see my track, I've sent the link to my shared page, and ask that they bookmark it. Then when they get my OK message, they can go to that bookmark.

My OK message currently says "follow me on my SPOT shared page". After I put in the APRS, it'll say, "follow me on aprs.fi"! :)

Ya know, I just re-read your post, and you are probably talking about the links to those folks shared page...my bad. In that case, it could be that they have their shared page set to display only the last 24 hours (other choices are 7 days and 30 days). If they haven't flown in that period, there will be no tracks.

OBTW, the TW fairing is working great! Thanks!

Cheers,
Bob
 
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