Impressions of the Spot unit after a month

[BrentHumphreys]

You passed right by my homedrome UNO, west Plains, MO

[N737Z]

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.



Don
RV7

[Louise Hose]

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.

[L.Adamson]

Originally Posted by N737Z

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

[BrentHumphreys]

I had a painful time cancelling. Long hold, disconnected twice while on hold. All told it took me over an hour to cancel.

[N941WR]

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.

[C-FAH Q]

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.

[Canadian_JOY]

Originally Posted by N941WR

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.

[eatenbyagrue]

Originally Posted by Canadian_JOY

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.

[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