Datalink Data Not Rcvd

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   I was out flying yesterday, and I got the "Datalink Data Not Rcvd" CAS alert (cyan) message.  But I had METAR flags for all of the local airports, so I went to the SYS page for the Datalink status and this is what I observed:

As you can see, the Service Level is ADS-B Wx (as it should be from my MLB100).  The Regional Nexrad data is 5 minutes old, the National Nexrad and METARs and TAFs are all zero minutes old.

The AIRMETS and SIGMETS are "Not Rcvd".  So this indicates to me that if any piece of weather information was not received, I get the CAS alert.  So my question is if that decision is made within the MLB or within the IFD?

I also took a picture of the Alerts screen.

Curious that instead of listing AIRMETs and SIGMETs, it just says AIR/SIGMETs twice.

Am I correct in assuming that there is nothing I can do (as pilot) to clear this alert?  Does this condition latch, or will it clear the next time the ground network broadcasts the not-received data to fill in the blanks?  How come I don't get this alert at the start of every flight?  (Before I climb into network coverage.)

David Bunin

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DavidBunin Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 20 May 2015 Location: Rockwall, TX Status: Offline Points: 742	Post Options Post Reply Quote DavidBunin Report Post Thanks(0) Quote Reply Topic: Datalink Data Not Rcvd Posted: 20 Dec 2015 at 2:18pm
	I was out flying yesterday, and I got the "Datalink Data Not Rcvd" CAS alert (cyan) message. But I had METAR flags for all of the local airports, so I went to the SYS page for the Datalink status and this is what I observed: As you can see, the Service Level is ADS-B Wx (as it should be from my MLB100). The Regional Nexrad data is 5 minutes old, the National Nexrad and METARs and TAFs are all zero minutes old. The AIRMETS and SIGMETS are "Not Rcvd". So this indicates to me that if any piece of weather information was not received, I get the CAS alert. So my question is if that decision is made within the MLB or within the IFD? I also took a picture of the Alerts screen. Curious that instead of listing AIRMETs and SIGMETs, it just says AIR/SIGMETs twice. Am I correct in assuming that there is nothing I can do (as pilot) to clear this alert? Does this condition latch, or will it clear the next time the ground network broadcasts the not-received data to fill in the blanks? How come I don't get this alert at the start of every flight? (Before I climb into network coverage.) David Bunin

DavidBunin Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 20 May 2015 Location: Rockwall, TX Status: Offline Points: 742	Post Options Post Reply Quote DavidBunin Report Post Thanks(0) Quote Reply Posted: 21 Dec 2015 at 5:50pm
	Also, I wonder if this issue will present itself more frequently once more weather products from the MLB100 are put into use on the IFD. Things like Lightning or Winds Aloft. The more products you add, the greater chance that at least one of them will be "Not Rcvd" at any given time (through no fault of the onboard equipment). David Bunin

DavidBunin Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 20 May 2015 Location: Rockwall, TX Status: Offline Points: 742	Post Options Post Reply Quote DavidBunin Report Post Thanks(0) Quote Reply Posted: 01 Jan 2016 at 8:10am
	Steve, I would like to understand the logic behind this CAS message a little better. On my Christmas trip, I saw it appear at times, and later clear itself. But I also saw times when the data on the Datalink page of the SYS tab showed items as Not Rcvd and the CAS message was not triggered at all. The Pilot's Guide says to refer to the web page, but I could not find a web page that discusses the warnings, just the one that has the features table. David Bunin