How to get satellite data offshore with Iridium Go and PredictWind.
When we decided that we were going to cross the Atlantic, we also seriously committed to offshore sailing, and our communications equipment needed an adequate upgrade.
That upgrade came in the form of our Iridium Go, which has given us the ability to receive weather and make calls while hundreds of miles offshore.
What is Iridium?
Iridium is one of the oldest players in the satellite communication market having made their first voice call in 1998.
Earlier in 2019, they commissioned their Iridium Next System, which will place 75 new satellites in orbit at a cost of 3 billion USD.
Iridium satellites are placed in low Earth orbit allowing for a bit better signal strength, lower latency and full coverage, including the polar regions.
Many other satellite communication companies place their satellites in Geostationary orbit, meaning the satellite is over the same point on earth all the time. Doing this ensures there is always coverage in that area however there is no coverage in the extreme latitudes (above 73 deg North or South) and depending on the network it may be regionally available (Spot is a good example of this).
Whenever we talk about things in space we are talking about systems that are extremely complex and have many limitations with data speeds, voice call latency and network disruptions.
But although these systems are complex, they work remarkably well! An important thing to remember (as with any GPS signal) the satellite signal strength is extremely weak, meaning a person needs to ensure a direct line of sight between the antenna and the sky for the satellite receiver to work. Anything disrupting this will ultimately cause signal degradation.
The data speeds for your Iridium Go are around 2.4 kbps. It is incredibly slooooooowwwwwww (Remember the days of the 14.4k modem? yep, even that was 7x faster than the Iridium Go!) But it works to get weather GRIB Files, send text email/SMS and make calls, which is all we need it to do.
What to think about when purchasing Iridium Go!
The Iridium Go comes with the Unit itself and some power adaptors, that about it.
However, if your planning to use the unit permanently on your boat I would suggest the marine mounting kit. This kit will allow for permanent installation as better signal coverage. As Satellite signals are extremely weak, having a clear, unimpeded view of the sky is extremely important.
This comes with an external antenna, a mount for a rail (e.g. the aft push pit, a solar arch or something else), a suction cup mount and all the wiring you need. For the most part, the kit is very good. my two gumps about this kit;
1. The rail mount is extremely ugly. In fact, it is so bad I took it to the local metal worker and had him change it for me.
2. The wire for the external antenna is extremely thick, so much so that I was unable to run it through my arch and now have an ugly black cable hanging on the outside of the boat (much to the dismay of Sophie.)
The last consideration is additional SIM cards.
Unlike a lot of phone companies, the satellite phone and internet industries operate through a somewhat hard-to-navigate world of dealers and distributors.
Onboard Polar Seal, we decided to purchase our Iridium Go through Predict Wind.
PredictWind has been our weather provider ever since we started sailing, and ordering our unit through our current provider was just the most simple alternative. Besides, PredictWind offers an unlimited Iridium Go plan (which we talk about a little farther in this article)
There is no such thing as walking into a local Iridium store to change your plan, which is what’s nice about the Predict Wind service offering; they are your data distributer and weather provider all rolled into one, AND they have really good support (both for billing and technical).
PredictWind/Iridium Go Billing Plans
The Iridium Go service offering through PredictWind current consists of 3 plans the most basic being 59.99 USD and the most expensive being 139 USD.
The Basic plan costs about 60USD and grants you 5 minutes of data transfer per month, free voice calls to landlines and calls to cell phones (or voice mails) for 1.29 USD per minute. Receiving SMS is free while sending them costs 0.25USD per message. Voice calls to other Iridium phones cost 0.65USD per minute while voice calls to other Sat phones cost a whopping 10.49USD per minute.
Onboard Polar Seal, we decided to go with the Unlimited plan for as long as we are going offshore for extended periods (i.e: until we reach the Caribbean, for now)
With the Unlimited plan, data transfer is unlimited. Meaning we can download as many weather forecasts as we want as well as send as many emails and SMS as we please. We have 150 minutes of voice call minutes (which should *hopefully* be enough in case of an emergency). Calls to other Iridium phones are free, but calling other Sat phones still comes outrageously expensive.
One thing to consider is that it costs over 200 USD to reactivate your SIM card, when you suspend your SIM card because you don’t need the service anymore, while activating a new sim card is free.
Thus my reason for buying a few extra cards (they are $10 each). You can, in theory, use a SIM card for your passage, deactivate the account and when its time to go offshore again active a new plan. The only drawback with this strategy is your phone number will change!
We have now been using our Iridium Go and Predict Wind for a few months with great success, all the way from Malta to Spain, from Gibraltar to the Canary Islands and from Lanzarote to Cape Verde.
We absolutely love the service, the ability we have to download weather forecasts every day or to send SMS and emails to our friends, family (and in some instances, even coworkers).
On top of it all, the Iridium Go/Predict Wind setup allows you to track Polar Seal's position in real-time on this very website! :)