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InReach vs. PLBs

maak
over 5 years ago
First off, I love my InReach Mini, and have no plans on replacing it. And I know the internet provides A LOT of wrong information. That said, I came across a recent post that made me want to ask this group of smart people if there's any truth to the claims, or was the writer being paid by PLB manufacturers? I get the feeling that later is true. But his article was a longer comparison clearly angled to why PLBs are better (so clearly slanted). It said-
Advantages of a PLB over anything else (cell phone, SPOT, InReach, sat phone): It has a powerful transmitter on a

band monitored by government agencies. There are no private parties. If you need rescuing they WILL come, they'll

be using top equipment to do it, and in general you don't have any liability for your rescue costs. If you're using a

private band device like SPOT or InReach or a sat phone, you will have such liability and you won't have access to

nearly as large a rescue network. SPOT and InReach also have much less powerful transmitters.

Disadvantages of a PLB: You can't post selfies to Facebook. You can't send a personalized message to anyone, for

any reason. You have to spend $100 every 5 years to have the battery replaced.


The article (longer than above) is clearly slanted in that I don't send selfies in my messages over InReach. I send communication that is important to let people who care, know my adventure status. That said, any truths behind stronger transmitters and larger rescue network?

Please tell me to stop believing everything I read on the internet!!! :)
  • 0 over 5 years ago
    After thinking about it, I'm not sure that what I said above regarding message checking on the Mini is entirely accurate. There is a difference between a "passive listen" and an "active check".

    A passive listen is just what it sounds like. The unit turns the Iridium radio on briefly and listens for a "ring" directed to it. This is a fairly cheap operation battery-wise. Unless it hears a ring, the unit only listens, and only does so briefly. There are no retries involved. AFAIK, there is no way to tell by looking at the unit how often this happens. I have it in my head that it occurs every 10 minutes on the Mini - and that this is the operation controlled by the message checking interval on larger inReach devices. I could be wrong about that, however.

    An active check involves actually transmitting a query to the Iridium network. This requires a reply. The unit will do at least a certain amount of retrying if it fails to get a reply. This is somewhat more expensive, both because it involves transmission and because it will retry if necessary. I believe this occurs at roughly 1 hour intervals on the Mini. I have no idea about the larger devices. The Mini does this because the passive listen is not very reliable for a variety of reasons.

    All the units check for messages whenever they send something - sent track point, message, or whatever. This is essentially "free" in the sense that the message waiting indicator piggy-backs on the acknowledgement to the sent item.

  • 0 over 5 years ago
    When I fly I have a PLB as part of the aircraft kit but I also carry a mini. In the UK you are going to get the same people coming out whichever device you use. The advantage of the inReach mini is you can inform them that your case may be non urgent so they can plan the use of resources better. As mentioned before, a PLB can be registered to a person in the UK but it is more normal to allocate it to a specific aircraft or ship registration. If you take your personally registered PLB out of the UK and activate it the response will be very variable depending on how you registered it. When I hike or ski in remote areas in Europe I use the inReach mini exclusively and wouldn't trust a PLB. The number of false activation's of PLB's is staggering and in some countries you would not get a response at all. When I was an airline pilot we used to report at least one PLB a flight. They actually cause a lot of grief for the authorities as they are so easily obtainable. Having said that, a PLB going off in a remote area will elicit the correct response, no question. An activation in Portsmouth harbour (and it happens there a lot) will be unlikely to get a SAR response. The huge advantage of the inReach system is that even in areas of cellphone coverage it is probably better to use it and let an english speaking agency which already has your details deal with the local (possibly non english speaking) authorities. Apologies to all our forum members whose native language language is not english!
  • 0 over 5 years ago
    Unfortunately, there are a lot of false activations with inReach and similar devices as well. However, because of the interactive features of the inReach, I doubt that an activation would be ignored outright without first communicating with the device/user in question.
  • 0 over 2 years ago

    PLB and InReach each have their place. The myths that some people have stated about each of them in the past are normally not true. At the end of the day, yes a PLB transmits at a higher wattage and helps penetrate ground cover and go over water and other “signal obstructions” but it is solely an emergency beacon… the InReach ties a communication and connection aspect with an emergency function in a smaller and lighter package. Yes, it is true that a PLB is monitored by the federal government, USAF AFRCC to be exact which uses SAR and Military Satellites. After alert, they notify Federal, Local and State SAR assets and can get to your location. Normally, as long as their is a true emergency, then you are not liable for anything for the response… but if you set it off just because, you will possibly be met with a lot of fines, to possible include: Local, State, Federal (FCC, SAR, (FAA for 121.5MhZ), etc). The myth that PLBs don’t give exact location is also false. Normally we are within 100m or less from the initial coordinates given to us by AFRCC. I personally like the InReach for hikers, and people gone for longer times in semi remote areas that want to stay in “courtesy” communication and also have the SOS functionality just in case. If you go more remote or want a super durable device with more personnel and resources backing your rescue efforts, i.e. more dangerous areas, or more austere conditions, then a PLB is a great choice. PLBs are built almost identically to EPIRBs from boats and function on the same network as the ELTs for Aircraft (Both 406.1 and 121.5) as previously stated. So they are very robust and almost overbuilt. The other difference between the two is battery life and the weight as I stated before. They both have their places in peoples gear and safety plans. I hope this helps. 

    - a Search and Rescue Team Leader

  • 0 over 2 years ago in reply to P_W_P
    P_W_P said:
    PLBs transmit at 5 Watts of power, while InReach transmits at 1.6 Watts. This suggests that the PLB signal might be received from under heavy cover or deep in a canyon, where the other devices may fail.

    this can impress only people with no knowledge in radio communication

    the smallest increase of transmitting power a radio receiving device will notice is 6db, meaning the transmitter would have to send 4x the power

    However it also depends widely on bandwidth. But essential is, who is receiving those signals. Today many of the transponders are traveling as kind of payload on navigational satellites, but also on geostationary satellites are transponders for it, and there are some low orbit satellites receiving the 406 MHz as well.

    So 1.6W communication with receiver at 780km distance and 5W communicating with receiver at 36000km distance are two completely different things.

    PLB have not necessarily  GPS inside, the location can be also calculated by doppler shift.

  • 0 over 2 years ago

    I have friends in SAR who deeply appreciate patients with the 2 way communications capability. There’s a ton of information you can provide in a text that a PLB doesn’t that really helps them do their job. It’s a huge deal for them.

    It’s also nice for less emergency communication. If I’m fine but running behind, no way should be hitting a PLB button, but I can text my girlfriend that I’ll be home at 11 pm instead of 7 pm, sorry but you don’t have to stay up and worry, which she appreciates. It’s also nice for coordinating logistics. Maybe I’m doing a six day hike and it’s point to point and someone is picking me up at the end - when we’re planning we won’t know exactly when I’ll be at the pick up point for us to plan our meet up, but I can text them and say “hey I’m 3 hours out” so they can know when to come get me or they can let me know when to expect them to show up.

    I bought a PLB many years ago back when the texting capability was a lot worse, at this point the only choice is between an Inreach mini for texting only or a full Inreach for mapping too.

  • 0 over 2 years ago

    I have some personal perspective of recent events that leads me to consider that, in fact, yes, the PLB might be the better option!  Or, that I still need to carry both!

    Amongst my numerous pursuits, I am a paragliding pilot.  Almost 4 weeks ago in June, I was a part of a group of 4 pilots with 1 retrieve driver that went to a local mountain to go flying.  Myself and one other pilot were in the air when the third pilot crashed after launch.  It was a very serious incident that required a helicopter.  The 2 people on the ground immediately initiated the SOS on the mini.

    The reply?  "What's your emergency?"  It took significant time ... probably 15+ minutes for emergency services to simply understand the gravity of the situation let alone deploy the appropriate response.

    Then came another question ... "We didn't get your GPS location.  What's your location?"  Are you serious???  The guys on the ground literally had to determine the location and then punch in the coordinates.  Umm ... why and who didn't get the location?  I mean, that's *** atrocious!!  We are able to have a chat, but you seriously don't know our location???  Not only this, but the dispatch to local resources from Garmin went to the WRONG county!!!  That county kicked it back saying that it wasn't their jurisdiction!  The guys on the ground had to tell Garmin, again through chat, which county was the correct one.  Now, this ordeal occurred through a Garmin Mini that was not mine, but the owner and user was not a person who didn't have a clue.  It's fortunate that he knew how to use it and communicate.  It's just unbelievable the response.

    However, this week, I again went paragliding.  We were waiting longer on launch than usual waiting for wind conditions to settle down.  We waited for 2 hours, so I wanted to send messages to my partner letting her know that I hadn't launched yet and to understand the timeline of things.  I'd had my Mini turned on for 90+ minutes.  I sent messages -- not preset messages -- messages counting towards my monthly allotment.  Every indication was that they went through.

    I eventually launched, and when I landed an hour later, I sent one of my preset messages that indicates I landed okay and don't need help.  When I arrived home, I asked her if she got my messages.  NOPE.  I sent four messages over the course of the hour prior to my launch, and not a single one of them went through.  She did however get my preset message send, thankfully.

    This rant isn't about the actual events and their outcomes.  It's about the execution.  I don't expect a GPS signal to work 100% of the time, but someone explain how a GPS SOS signal does work and be received but no location data???  Then the response!  Then I am paying a subscription for messages per month, and they don't go through even when I have a preset message go through afterward!

    I really wish ACR would develop their products into 1 combined device ... a combined 2 way messenger using Iridium and emergency beacon signal to COSPAS-SARSAT.  I don't care if it would be heavier than carrying both the Mini and PLB.

    I expect better from a premium business.

  • 0 over 2 years ago in reply to Ready4Launch

    And, when I say GARMIN as the response, I know it is Iridium and not GARMIN.  However, GARMIN post-review of the major incident, GARMIN basically shrugged and didn't care to help.

  • 0 over 2 years ago in reply to Ready4Launch

    While they are definitely some technical reasons on one side, there should be proper investigation at the IERCC/GEOS why certain things go wrong. You should insist at least to get clear reasons what went wrong. The process is complex, so tings can go wrong, but whole system has also to learn from problems.

    I am not sure if the move from GEOS to IERCC of Garmin did help to the users.

    I got very recently some very frightening experience with emergency (test) call and IERCC was not able to contact the predefined phone number while everybody else had no problem. What did happen was found out and communicated, but  this can not happen in real emergency call.

    What gps fix concerned, one has to notice how real gps works. To get a fix, the receiver has to be switched on for some time under free sky. OK, today a gps receiver has not to wait the full 22min as it used to be 30 years ago. But still, it has to obtain some orbital data from the satellite and this is very slow communication. So switching on a receiver can take quite some time until a position is calculated and important: useful.

    The same problem or even worse will have PLB. This is in general switched off, if switched on, it starts sending alarm. But where should it take gps position when it has no satellite orbit data available? If it has some almanac rests stored, this might be 1 year old.

    Clearly, the doppler shift measurement done by the sarsat will take immediate action, but this position area might be fine for ships on the ocean, but give you also position 'in other county' as it simply can not do more.

  • 0 over 2 years ago

    Accuracy probably isn’t the correct term. Both devices are going to be pretty much the same when it comes to accuracy. They use a GPS receiver to identify your location and transmit that to the satellite. The Iridium Sats are in a slightly lower orbit than the LEOSAR sats, but the 406MHz signal will penetrate through clouds slightly better. The biggest difference is that unless your PLB has the return link feature, there is no confirmation of receipt. InReach will confirm your message got through and SAR can contact you to get specifics about your situation to better prioritize response. That kind of service is on the roadmap for SARSAT but isn’t available yet.