Iridium vs Inmarsat for trans-Atlantic

[skipmac]

Originally Posted by AllenRbrts

For those needs a GO would work great. We have done lots of passages with it. What is your passage plan? We are going east mid May to the Azores

Boat currently based in north FL. Plan is to move a bit north the leave mid May for Bermuda. See Bermuda, pick a weather window and head for the Azores. From the Azores still deciding. Eventually to the Med but might go north first.

[skipmac]

Originally Posted by maine50

We did Atlantic Circle ( New England to Azores to Madeira to Carib in 2017/2018 with a Inreach. I had a brother doing the weather from New England (sitting at his computer) and texting routing. We also got weather from Ocens at a very low price. Family had location updates and ability to communicate with us. It also had a Emergency function. This might work for you

Since I already have a Garmin Inreach I may stick with that. My main question is whether adding a full satphone to the kit would be worth while.

[skipmac]

Originally Posted by yelken

Hi skipmac,
Please also check; BIVY Stick from ACR. An extract from its description "Use the Bivy Stick to turn your cell phone into a satellite communication device. With global satellite coverage via the Iridium satellite network, anywhere you have a view of the sky, you can communicate through the Bivy Stick. While conveniently compact, the Bivy Stick still offers a comprehensive feature set including two-way text messaging, SOS, location sharing, one-touch Check-in, and detailed weather reports sent straight to your cell phone via satellite. Additionally, offering a feature not provided with many other satellite communicators, the Bivy Stick provides users with a dedicated phone number and email."
https://www.acrartex.com/products/bivy-stick/


Interesting cost and activation concept. No affiliation with the company and have no experience with the product also.


Good luck with whatever you decide.
Yelken

Interesting. Have heard of something like this in the past. Checking it out,

[skipmac]

Originally Posted by AllenRbrts

Satellite communicators like inReach, Spot, Zoleo are great (we have an inReach as well as our GO) but if your use case includes getting weather gribs, Predictwind or weather emails (if doing long passages you really will want), you probably need at least a GO.

Think I have to research the GO system a bit more. I had assumed it was similar to Inreach but if it can download GRIBS that's beyond what Inreach can do.

[Amapola]

We are very happy with inReach for our cruising territory: ICW; SW Florida to Annapolis; Bahamas Abaco, Eleuthera, Exumas; Florida Keys to Dry Tortugas; and this year we plan to head to the Rio Dulce, Guatemala.

[fogmachine]

I've used both in the Pacific; the convenience of the Inmarsat Fleet One made it far superior to the Iridium Go if you can swing it; for the price the Iridium Go is a pretty good deal.


No matter which you choose, make sure it's enabled a few weeks early and practice with whatever software you choose for weather, etc. I've known too many people that didn't and ended up with nothing but frustration and high sat phone voice bills.

[earlyviking]

I use Zoleo now. In the past I used Garmin inReach for coastal sailing Seattle to Alaska & bit off shore.They use same Iridium satellites [60+6 spares]. Garmin subscription plan may work ok for limited time period like Transatlantic but is not helpful for EMS & S&R crews who need intermittent high use service on an affordable plan .

Spot has limited Satellites & coverage

Zoleo also using Iridium has excellent subscription plans: $20/mo for 25 messages $50/month for unlimited. The difference Zoleo compared to Garmin is: if use text or email from the Zoleo app on your phone [that via Bluetooth] sends satellite message to Zoleo device when in civilization. & you have wifi or cellular service the Zoleo app sends message by cheapest method, cell. wifi or satellite- saving costs. This is perfect for EMS, S&R and coastal sailors that have intermittent cell in the field or wifi [back at the office] even on some areas of the Southern BC coast & also in Johnstone strait. Of course that is irrelevant on ocean passage.

However the zoleo has another huge advantage over Garmin: When message is sent from Zoleo app on your phone to any cell number or email address in the world & that person has free Zoleo app on their phone [even without Zoleo subscription] then you can send a 950 character message instead of the [Garmin] 160 character messages., This allows S&R & FIRE & EMS to send very detailed medical message or message about changing rescue conditions to anyone who is willing to download the free app [assuming the other person has wifi or cell] You can also exchange dedicated Zoleo email & phone numbers w other Zoleo users & send Zoleo to Zoleo, automatically via the cheapest method: cell, wifi & if not they are not available via satellite.

Garmin's inReach requires the responder have internet & capability to do web mail & -though inreach to inreach is possible also w exchanging numbers but they do not give you a real phone number [Like Zoleo] that you can give to someone & say text me - you have to use the webmail app for Garmin.

One other advantage to Zoleo & InReach satellite text devices over Sat phone only comms is that I can send the text message from my phone, to device then forget about it, till device finds the clear satellite sky view & sends the message. If I am away from Sat phone I miss the call, not so w sat text devices - Of course most sat phones can also text but total cost is much more.

I currently use Zoleo for both Coastal sailing & Disaster management exercises, & receive no renumeration from Zoleo. I am aware of above details as we are currently setting up our Disaster Management communication systems for two adjacent counties in Western WA -

Re: weather & Dark Sky: I find the Dark Sky weather not even close to real conditions, practically useless [at least in the PNW & Puget Sound] much like the Environment Canada VHF reports for coastal BC.

I use OCENS weather text system for true marine weather including off shore conditions. Dark sky when I checked previously used ground stations [in Johnstone strait for instance] not the standard marine stations like Fanny Island that are located in the marine weather environment. You can add Ocens weather & tracking for about $15/ mo for expeditions when you are completely off grid. to either Zoleo or Garmin plans.

I purchased Sat weather weather thru Ocens in the past when using inReach when using Zoleo because its true marine location based weather, that in my experience matches ground, sea conditions especially in the coastal areas where neither off shore or land based weather is representative.

[sv_pelagia]

Originally Posted by earlyviking

I find the Dark Sky weather lousy & practically useless [at least in the PNW & Puget Sound] much like the Environment Canada VHF reports for coastal BC. .

Agree about Zoleo positive comments.

BUT totally disagree with negative comment about Environment Canada forecasts! They're good (but, as with all forecasts, not always exactly correct, and they tend to overestimate winds). Expert forecasters familiar with land effects etc produce forecasts.

OCENS forecasts do not take in to account local effects such as promontories, fiords, depths. Mainly for offshore (same as gribs). Models only, no expert human input.

[sck5]

"Also as a way for friends and family to contact the boat if there's a problem at home."

We found this to be a bad idea. Do you really want to be floating around, days from any port, and then add on top of that a crisis that you can do NOTHING about from a boat at sea? People dealt with crises just fine before the days of instant total communication and they will deal with them now if they have to. You can always check in as soon as you get wherever you are going. And when you get there, the cheapest way to call home is almost always a local SIM card. The locals have to call the USA too, and you can trust them to have found the cheapest way to do that. It is never a satellite phone. Besides, keeping a sat phone turned on all the time when at sea is a pain. You have to keep charging them and they need an external antenna if you are keeping them below decks.

Having said that, it is a good idea to have a phone to call for help if YOU get in trouble. I found one on ebay for cheap and it even already had the Coast Guard number programmed into it.

[ka4wja]

Skip, et al,
I have both some real-world experience and advice to offer you....AND some engineering info as well...

It's just that I don't have the time right now...
Hopefully tonight or tomorrow?

'Til then, just a quick fyi...
In addition to being an HF radio fan (radio nut!), I also have an Iridium 9555 that I have used offshore and on-land....and, I was a beta-tester of Iridium in the 1990's (along with my brother, who was a Motorola Engineer)....and, have used INMARSAT over the years....(oh, and you know, I have made my living in commercial sat comm)


73 and Fair winds.

John

[skipmac]

Originally Posted by ka4wja

Skip, et al,
I have both some real-world experience and advice to offer you....AND some engineering info as well...

It's just that I don't have the time right now...
Hopefully tonight or tomorrow?

'Til then, just a quick fyi...
In addition to being an HF radio fan (radio nut!), I also have an Iridium 9555 that I have used offshore and on-land....and, I was a beta-tester of Iridium in the 1990's (along with my brother, who was a Motorola Engineer)....and, have used INMARSAT over the years....(oh, and you know, I have made my living in commercial sat comm)


73 and Fair winds.

John

Thanks John. As always your input is greatly appreciated. In this area you have clearly been there, done that plus it's nice to hear from neighbors.

Knew you did antennas and related but didn't know it was for satellites.

Anxiously await your further input.

[skipmac]

Originally Posted by sck5

"Also as a way for friends and family to contact the boat if there's a problem at home."

We found this to be a bad idea. Do you really want to be floating around, days from any port, and then add on top of that a crisis that you can do NOTHING about from a boat at sea? People dealt with crises just fine before the days of instant total communication and they will deal with them now if they have to. You can always check in as soon as you get wherever you are going. And when you get there, the cheapest way to call home is almost always a local SIM card. The locals have to call the USA too, and you can trust them to have found the cheapest way to do that. It is never a satellite phone. Besides, keeping a sat phone turned on all the time when at sea is a pain. You have to keep charging them and they need an external antenna if you are keeping them below decks.

Having said that, it is a good idea to have a phone to call for help if YOU get in trouble. I found one on ebay for cheap and it even already had the Coast Guard number programmed into it.

Yes absolutely. If one can speak with the family there's always the ability to offer sympathy or moral support to those at home if a death or similar tragedy occurs. If some other crisis one can offer advise for dealing with a problem.

And if it's something that requires a return home, knowing in advance would allow faster arrangements for flights, securing the boat, dealing with crew, etc.

[goboatingnow]

We found this to be a bad idea. Do you really want to be floating around, days from any port, and then add on top of that a crisis that you can do NOTHING about from a boat at sea? People dealt with crises just fine before the days of instant total communication and they will deal with them now if they have to. You can always check in as soon as you get wherever you are going. And when you get there, the cheapest way to call home is almost always a local SIM card. The locals have to call the USA too, and you can trust them to have found the cheapest way to do that. It is never a satellite phone. Besides, keeping a sat phone turned on all the time when at sea is a pain. You have to keep charging them and they need an external antenna if you are keeping them below decks.

A sat phone is extremely handy when you need it, I don't do long journeys without it , especially to keep my wife calm if we are delayed getting into port ( 4 days late is my record )

Typically you dont leave it on all the time, unless you have an external antenna

[ka4wja]

Skip,
Not sure how detailed of an answer you want?
And, since I have no idea what your budget is?

Nor where you're planning on voyaging, specific recommendations are pretty difficult (as you can see from the wide variety of opinions posted over the years)?

So, here's just a brief one, if you want more, let me know....but, you're going to need to provide some more detail, such as your present equipment (MF/HF-DSC-SSB Radio?; EPIRB?; laptop?; tablet?: solar array size?; smartphones?; etc. etc. etc.), your planned voyaging....and especially your safety and communications budget?

(Fyi, as I wrote earlier, as well as being a confirmed "radio nut", I've made my living in communications, mostly commercial sat com....and have used Iridium for decades, as well as INMARSAT...)

First some facts and explanation....(then some recommendations)...


1) Iridium works the same everywhere....it is the same at the poles as it is at the equator, and everywhere in-between, on-land or at sea...unless there is an extremely rare satellite issue, it is the same everywhere....

INMARSAT uses geostationary satellites, that cover approx +/- 70 degrees maximum north and south latitude and +/- 70 degrees east and west of their orbital longitude....(+/- 60 degrees is the recommended max).....and, while it does work better at lower latitudes and closer to one of the four satellite longitudes (there are two that cover the Atlantic, one over the Pacific, one over the Indian ocean), you do need to point/orient the handheld's antenna.

In general, Iridium is hands-down the better choice, in handheld and/or very-low bandwidth (2.4kb/s) sat comm systems, between the two --- Iridium and INMARSAT.

In higher-bandwidth (so-called "broadband" speeds above 250-300kb/s) sat comm terminals, INMARSAT has a small advantage (although, if I was in the market, I'd buy the Iridium Certus....in my personal opinion, it's better than INMARSAT FB systems) with terminals starting at $5k to $10k and up....but, usually those needing that kind of speed, opt for VSAT Ku-Band terminals (some guys even go with both Certus or INMARASAT along with VSAT terminals), with speeds over 2Mb/s up to 50Mb/s (starting ~ $15k - $20k...up-to ~ $75k)....but, unless your budget starts in the 5-figures, most of this is pretty moot.

FYI, none of the small low-speed sat comm devices, "GO", handheld sat phones, etc. are suitable for heavy-weather use / heavy-weather distress calling....trying to hang on, while trying to use a handheld sat phone, or trying to send an SMS distress call from a smart phone, while in heavy sea, etc. ---- not something that anyone should ever try....this is what EPIRB's and MF/HF-DSC-SSB, and INMARSAT-C, is for! (or, if you have the $$$$ for a GMDSS sat comm terminal, maybe a GMDSS-certified Certus or FB)

Fyi, both Iridium and INMARSAT are L-Band mobile sat comm systems and both generally work in rain, but Iridium works better in rain and heavy-weather....but until you've tried to use a handheld sat phone of any kind, in heavy weather (or tried to use a smartphone connected to a "GO"), you might not grasp why they are the worst choice you can make for Distress comms (more later on this, if you desire).


2) BTW, one distinct advantage of Iridium is the lack of necessity to "point" the antenna at the satellite, like you must do with INMARSAT. Of course, you do need a clear view of the sky, but as the Iridium system uses multiple satellites at lower-earth-orbit, there is no need to "point" the antenna, as long as you / your phone (or external antenna) is out in the clear, Iridium is good-to-go. INMARSAT (whether handheld or fixed terminal) uses geostationary satellites (at ~ 22,300 miles above the equator) and as such needs their antenna pointed in that direction (although the width of the angle of the handheld's antenna is wide, it does need to "pointed" towards the satellite).

In the almost 25 years (on and off) that I've been using Iridium, I've never had a dropped call (although, I did experience some call break-up, when testing/evaluating the system...when driving under heavy tree cover, under bridges, etc....which was to be expected, of course).....but...knowing the above, you should start to see why some folks say they have "dropped calls" with Iridium ---- probably 'cuz they never were explained that (like all satellite communications) it is line-of-sight communications, and if you block the view between the sat phone and the satellite, whoops you get call break-up and/or dropped calls (if the satellites that are supposed to take your call "hand-off" are being blocked from view by something on your boat....whoops, you can get call-break-up until you're routed to another satellite, or in some instances, a dropped-call) but this is not the fault of Iridium, nor the phone, etc., it is the fault of the user.

And, if you extrapolate this (no need for engineering degree here, just some common sense), and look at INMARSAT, you'll see that while you do need to point / orient the antenna, as long as you keep the antenna pointed / oriented towards the satellite, you should have less call break-up / less dropped calls....but...

But, surprise - surprise, if you kept the Iridium antenna relatively in the clear, you'd not have any call break-up, nor dropped calls at all! (btw, in the clear does not mean a complete open horizon-to-horizon, but generally in the open such as in the cockpit of a sailboat, etc.....not in a pilot-house)

So....

So, now you might see why you get varying opinions and different experiences, from different sailors....it's almost always because various users actually use these things differently (and some use them incorrectly)...

Also, please be aware that unless you have an external antenna mounted above decks (in as clear a location as possible), and leave the sat phone (or "GO" and your smart phone) connected and on all-the-time, you're not going to receive calls from someone trying to reach you....this is satellite communications and if you want to be reachable, you will need some additional hardware and make allowances for power consumption, etc....(most that have this need, either use a "sat phone dock" and external antenna...or bite-the-bullet, and install a real sat comm terminal costing > $5k)...
To be honest, the one thing I miss most about WLO (or even the old AT&T stations WOM and WOO) was their hourly traffic lists...but, if you're a ham operator, you can easily have anyone on-shore that wishes to contact you just have a MMSN net controller list you on their contact/traffic list, and all you need to do is listen once or twice a day, to see if someone is looking for you...a simple fact is that if you need to be that reachable (24/7/365) you can afford to buy the proper terminals / equipment ($$$$)....the rest of us, we just revel in the peace of being out there!


~~~~~~~~~~~

And, one important fact here....with the exception of FB / Certus GMDSS certification, none of the above is "new"....when you write that you want "recent threads comparing the two", I just want you to be aware that nothing much has changed in the past year or two / past couple years....(some improvements in the higher-speed terminals and lots of advancements in the broadband/hi-speed terminals and services, but for most of us here, those are not what we can afford, so I'm not discussing them here)

~~~~~~~~~~~~~~~~


3) In order to give you some recommendations there is a very important question ("what are you going to do with sat comm?") that I'm not completely clear on the answer.
{you seem to indicate your primarily desire to use sat comm for weather info/forecasts? for "downloading raw computer model data (GRIB's)", rather than use human-drawn synoptic weather charts / forecasts (such as those from the US NWS/NOAA, via WeFax and SSB Voice)....which seems odd, but I assume you've made this decision already? but, here are my recommends, regardless...fyi, the other weather apps mentioned here, PredictWind, etc. etc., all are just the raw computer model data, presented in some color-graphical-way, to appear to be "value-added"....further fyi, nothing wrong with them, and both OCENS and PredictWind have a good reputations, and OCENS does have some value-added features / services available...just be aware of what you're getting... }


a) If you're looking for routine satellite telephone calls and/or low-speed routine data, short personal emails, I can recommend the Iridium 9555 (I've owned / used one for years, used it on-board and on-land....in US, N. Atlantic, NZ and Australia). {although, some will recommend the IridiumGO, I have heard that making phone calls thru the "GO" is problematic, but I have no personal experience with the "GO", so before you make a choice be sure to really speak to someone that has actually made/received phone calls thru the "GO", not just someone reposting something that someone else wrote, about what they heard, etc.)
{fyi, PACTOR 3 is twice the speed of Iridium or INMARSAT sat phones or "GO"....and PACTOR 4 is twice the speed of PACTOR 3, or about 4 times the speed of Iridium or INMARSAT sat phone or low-speed data.....but, of course, PACTOR requires the purchase of an external (and expensive) modem, for this data....and with the cessation of most public coast station's radio-telephone calling, many sailors that never purchased a PACTOR modem, have opted to use sat phone for offshore telephone...and hence, also for low-speed data comms....but, in general, PACTOR is superior...}


b) If you're looking for safety, urgency, and distress comms, I recommend MF/HF-DSC-SSB Radio (such as Icom M-802 or M-803, with AT-140 tuner)

Btw, your words regarding seeking medical assistance at sea....be aware, unless you have a real sat comm terminal (not a handheld sat phone or "GO"!), the best / easiest is HF Radio (MF/HF-DSC-SSB Radio)! Yes, still in 2022, this is still a fact of life....[btw, if you don't have a MF/HF-DSC-SSB Radio, you should really, REALLY reevaluate your safety budget / communications budget, before you even think about "getting weather" or "sat comm"]

MF/HF-DSC signaling will raise both DSC coast stations and 1000's of merchant vessels (many of these vessels may be in your area and can offer rescue if needed)....after you've signaled via MF/HF-DSC your "Urgent" message (or Distress if it is needed), you can communicate directly with a physician (or nurse, or EMT, etc.) via SSB Radio, either from US Coast Guard or other such radio station you've raised...
I know, I know "everyone" says they'll just use their "sat phone" to call for help, but are you really going to go out on deck to try to communicate in a medical emergency, or try to hold your smart phone steady if you're trying to use the "GO" with an external antenna? Please understand that while what some sailors are "sold" is not a viable reality on our small boats at sea....we are not on large ships, with lots of ship-borne infrastructure, and most times it's just two or three people on-board....in urgent or emergency situations, you need what works / what works easily / what is always reliable, and that means using part of the GMDSS, not trying to rig up a cheap-n-dirty work-around, just 'cuz "some guy" told you that is what they did! (ask him if they really used this thing in an emergency, in heavy weather, with an injured crew, etc. etc....if not, please look to the GMDSS, 'cuz it works!)


c) If you're looking for good weather info/forecasts, I recommend HF WeFAx reception, whether using a simple/inexpensive HF receiver or using you HF-DSC-SSB Radio, or a dedicated WeFax unit...(remember there is NO need for any PACTOR modem here)

Have a look here:

Good HF-WeFax Reception, On-board at the dock, March 2021 (real-world)

https://www.cruisersforum.com/forums...ld-248424.html


Offshore Weather

https://www.youtube.com/playlist?lis...zdjTJjHlChruyY

https://www.cruisersforum.com/forums...ea-103555.html

https://www.cruisersforum.com/forums...ds-146617.html


Maritime HF Comms

https://www.youtube.com/playlist?lis...ZDo_Jk3NB_Bt1y


HF-DSC Comms

https://www.youtube.com/playlist?lis...ga2zYuPozhUXZX



4) I'm curious as to who/how is "tracking" you? Actually, I'm more interested in "WHY?" they are tracking you....but, that really none-of-my-business, and doesn't effect my answers here....so...

So, back to my question as to "who" and "how" someone is tracking you?

And, to a lesser extent, how / why are you going to rely on their "interpretation" / "regurgitation" of the weather....is this a professional weather router, etc.? even if so, I'd be hesitant to consider any of them over the US NWS NOAA forecasters (each of whom, sign their name to each and every offshore and hi-seas forecast, you know)....if not a professional weather router, fyi, you will be MUCH better served using the US NWS NOAA weather forecasters, and/or those of the UK, German, and French Met offices (for the Atlantic....and/or US NWS NOAA and NZ and Aus Met offices forecasters, for the Pacific, etc.)



5) As for "sat comm plans"....there are variations between vendors as well...

I have used Outfitter Satellite, and have good luck with pre-paid plan for my 9555.
https://www.outfittersatellite.com/


I have also had good luck with Atlantic Radiotelephone / SatPhoneStore (but, some sailors have not had good experiences with them....so, be cautious here)
https://www.atlanticrt.com/
https://www.satphonestore.com/
https://www.iridium.com/company/atla...satphonestore/



6) Skip, I just saw page 2 of this thread....where you mentioned a eastbound Atlantic crossing, US-Bermuda-Azores-Europe...(sounds great....but, I'd skip Bermuda, but that's just me)

Now that I know this, I highly encourage you to use HF Radio for your weather info / forecasts, while offshore and in remote locales....(see my videos and my recent thread on this....linked above!)

You will find both the US NWS NOAA WeFax, mainly from NMF in Boston (and mostly the tropical N. Atlantic from NMG in New Orleans) to provide you great coverage and excellent weather forecasts for the whole N. Atlantic....and, if needed, the UK Met Office WeFax (from GYA in Northwood, England) will do the same for the eastern N. Atlantic and Med...

These are the gold standard of offshore maritime weather forecasts, and are still to this day, used by the majority of commercial ocean mariners / merchant vessels!

Btw, the USCG SSB Voice Offshore forecast broadcasts are great, but they only cover out to about 250nm from shore....the Hi-Seas forecast broadcasts cover 2/3's of the Atlantic, but are rather course in their detail (very general forecasts, but for most they're fine, 'cuz what you really want is to know about storms, etc., and they are of course covered)

(for further weather info in the UK and the Med, you'll have excellent cellular/mobile coverage, but if out-of-range, GYA and DWD are good for WeFax....but, also be aware of the excellent BBC shipping forecasts on LW, 198khz (?) as well as NAVTEX which has good weather forecasts for just about the whole UK, North Sea, and Med...)


I do hope this helps.

Fair winds.
John


P.S. Please ignore Globalstar....if they was ever a "misnomer" for a company name, this is it....yes, their data rate is better, but they're not that reliable of a system....(and I'm not even sure if they're still doing business?) And, while Thuraya (Europe, Africa and Middle East coverage....and Asia / Aus, from another satellite) has a "sat-sleeve", and it worked somewhat, I'm not aware of anyone that ever used one successfully offshore, so best to steer clear of those, as well...

[skipmac]

Thanks John, As usual the complete answer on the subject. Did a quick read through but will have to take a little time to study and absorb all the detail.

But to answer some of your questions.

Budget. Of course don't want to throw unlimited funds at a solution but will spend what it takes for the right solution. Which then brings up

Goals. First or at least the most frequent use will be for weather and routing. Second, keep family up to date on location and status. Then of course comms and emergencies.

Equipment on hand. VHF (of course), EPIRB, AIS, Icom M700P and SGC Sg-230 coupler, Garmin InReach.

Icom not installed but think I could do that easily. Thinking about a separate, end fed long wire instead of cutting a stay. Would run the wire from the port side, midway between the shrouds and back stay. Comments?

InReach I have used to send weather to son in law cruising the far Bahamas and he would return the favor. He isn't a meteorologist but well experienced and qualified to do the job I think.

Route. US east coast to Bermuda, to Azores to Med. Departure more or less mid May depending on weather windows.