ADS-B Wx vs. Sirius XM Wx

[The rogue]

I'm a new CFI-I who owns a share of a Bonanza for three long multi state cross countries and lots of shorter burger runs a year. We just lost Starlink, like most of us did, and are ADS-B weather only for now.

Most of my flying is March-October in the upper Midwest, home base is Michigan.

Will there be a significant operational difference between ADS-B weather and Sirius WX for these kinds of missions?

For the folks that went from ADS-B weather to Sirius XM Wx, what are the advantages? What did you like? What did you not like?

Thanks for the help...I guess I'm trying to talk myself into another subscription, and a widget on the dash.

--Matt

 

[M20K]

Below is a link that might give you a little more insight into the two system. It will be interesting to see what others that use both have to say. I've got a StrikeFinder that's still working fine and ADS-B (FIS-B) and my primary rule is just not to go near any major storms. So ADS-B is just fine for me to avoid things I shouldn't be flying my Mooney into.

https://www.sportys.com/blog/datali...dXC8Rg-yvbbvjG3JwGL4tOwnX8G-s4ORoCyCMQAvD_BwE

 

[dans2992]

I prefer Sirius. Seems to be more accurate, IMO.

 

[AV8R_87]

For the folks that went from ADS-B weather to Sirius XM Wx, what are the advantages? What did you like? What did you not like?

I didn't see any advantages with Sirius. Seemed to be about the same data delay, and similar data quality.

 

[FORANE]

I prefer Sirius. Seems to be more accurate, IMO.

Agree with the above. I have had ads-b and Sirius for many years. I believe the Sirius data quality is superior and their delay is less.

 

[decalogue]

You do realize BOTH are far too slow to be used to navigate close range around convective activity.

Especially if IMC


It’s a “planning” tool not a “maneuvering tool”


This has killed people

“Probable Cause and Findings

The National Transportation Safety Board determines the probable cause(s) of this accident to be:

The pilot’s inadvertent encounter with severe weather, which resulted in the airplane’s left wing failing in positive overload.
Contributing to the accident was the pilot’s reliance on outdated weather information that he received on his in-cockpit Next-Generation Radar (NEXRAD).”



Pilot killed had about 390hrs TT


Also a reason for this rule

Ҥ135.173(a) & (c).

No person may operate a passenger carrying aircraft with 10+ seats (excluding pilot seat), except day VFR helicopters, unless equipped with approved airborne weather radar or thunderstorm detection equipment. Cannot begin IFR (IMC) flight if thunderstorms/hazardous weather expected along route unless equipment is operating”

 

[Kitch]

I use both. Panel mounted XM ads-b on the Ipad I prefer the XM feed always seems a little more accurate to what I see outside. The other nice thing about XM is it works on the ground before you launch.

 

[Dixiebluesky]

xm has a much higher resolution. Where it really shines is on a leg where you are covering a decent distance. ADS B starts to tighten up the closer you get to an area but I like to be able to look at stuff and how its changing while still a ways out. Accuracy for whatever reason does seem consistently better on xm. I can be flying through red on ADS B while looking at the cell out the window while XM depicts pretty well the true location despite the delay.

No it is not meant to try to shoot a mile wide gap between cells but is still an amazing tool.

 

[flyingcheesehead]

I prefer Sirius. Seems to be more accurate, IMO.

xm has a much higher resolution.

So, XM does have the higher resolution NEXRAD nationwide, while ADS-B only broadcasts it within something like 250 miles and has a lower-resolution nationwide radar feed.

However, a lot of people think the XM radar is "more accurate" or "higher resolution" even within 250 miles - It's not. The reality is that it's the same data, and XM just has a prettier presentation on a lot of devices. Caveat emptor.

Personally, I fly a 175-knot airplane, so ADS-B gives me high resolution for anything within about 1.4 hours of me, which is good enough for me. I've only wanted a higher resolution picture farther out a couple of times, and it's just not worth the extra $$$ for that for me.

If you fly something that's 250+ knots, the XM is probably worth it... If for nothing else than comparing with your onboard radar.

 

[The rogue]

You do realize BOTH are far too slow to be used to navigate close range around convective activity.

Especially if IMC


It’s a “planning” tool not a “maneuvering tool”


This has killed people

“Probable Cause and Findings

The National Transportation Safety Board determines the probable cause(s) of this accident to be:

The pilot’s inadvertent encounter with severe weather, which resulted in the airplane’s left wing failing in positive overload.
Contributing to the accident was the pilot’s reliance on outdated weather information that he received on his in-cockpit Next-Generation Radar (NEXRAD).”



Pilot killed had about 390hrs TT


Also a reason for this rule

Ҥ135.173(a) & (c).

No person may operate a passenger carrying aircraft with 10+ seats (excluding pilot seat), except day VFR helicopters, unless equipped with approved airborne weather radar or thunderstorm detection equipment. Cannot begin IFR (IMC) flight if thunderstorms/hazardous weather expected along route unless equipment is operating”

For sure. I'm looking for a good strategic planning tool that has good coverage and reliability.

 

[flyingcheesehead]

I prefer SiriusXM to FIS-B. There are several important differences, but I like the fact that I can get a coast-to-coast NEXRAD image and a full set of data before I depart...with FIS-B you may not start picking up weather data until you are above the pattern altitude or potentially higher depending on your location.

Those can be obtained using the Internet immediately before takeoff too, though.

 

[sourdough44]

I think I liked XM better but moved over to ADS wx years ago. It’s plenty good enough for what I do. I mostly have on the iPad mini with my Garmin Pilot app.

I also see it as a supplement to the usual weather check on the net before you go near the airport. One should have a good idea what’s going on before you get to any inflight weather.

 

[M20K]

but I like the fact that I can get a coast-to-coast NEXRAD image and a full set of data before I depart...

Yea, what @flyingcheesehead said... Not sure what you fly, but I will always get a "big picture" right before I depart via the Internet when I'm also getting a fresh Pack for ForeFlight. But then in reality, that Wx is only good at that moment in time. So sure, you can get Wx further out in flight, but once I'm in the air, I really can't out fly the more detailed Wx I get via FIS-B in my Mooney. And I'm really only looking to see if there is anything big along my Clearance Route so I can watch the progression and see if I need to start asking for a deviation early on. And so far, the METARs have also been available far enough out to get a good picture of local Wx on the ground as well.

And don't get me wrong. I'm not opposed to Sirius Wx. Just pointing out that, so far, I have not seen any "must have" items for the flying I do.

 

[M20K]

I was out in western North Carolina not too long ago and couldn't get cell service at the airport.

I've noticed a lot of airports with limited cell coverage often have an open WiFi connection so you can check Wx.

 

[Llewtrah381]

I started off with SXM 17 years ago on a Garmin 396. I added a Freeflight RANGR in 2010 and had ADS-B on a tablet with Avare. With that app, SXM was without a doubt better.

But then I switched to a GDL50 feeding an Aera 660. I sat in the hangar and looked at SXM, ADS-B, and internet (on Skyvector) side by side to see if I could cancel the then-$400/yr subscription to SXM. All three were effectively identical for details and refresh, as I recall. I stopped the SXM and have never regretted it. Note, though, that Garmin does seem to use a slightly different scale for intensity the seems to overstate it, in my experience (a safer way to err).

I highly recommend ADS-B via a Garmin input rather than Avare or similar. I think good resolution for 250 miles out is good for any aircraft except maybe airliners; sorting the pepper from the fly poop for several hours away seems a bit silly.

Bottom line, I think ADS-B In on a Garmin setup is functionally equivalent to SXM and internet.

But if someone wants to shell out for the SXM subscription, have at it. It’s just not a good bang for the buck, IMHO.

 

[theplanesalon]

One of my aircraft ended up having XM and a stormscope installed while I was visiting the factory years ago. It wasn’t cheap.

It does seem to have better resolution and the updates are a little fresher compared side by side - just My opinion

 

[Steamflyer]

No functional difference having used both. Going to go where the cells are not, so minor resolution and possibly age differences don't really matter operationally. And in the end, the Mark I eyeball is going to be the deciding vote. And once in a while, in the words of Gann, "you're going to take a pounding."