ForeFlight... it's not just ADS-B anymore (Sirius XM)

TangoWhiskey

TangoWhiskey

Touchdown! Greaser!
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arnoha said:
This is cool. Of course, it begs the question of, "How many devices can I put on my glareshield before the flight is considered IMC?" :)
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Have you seen some of the retarded pilots already mounting iPads to the windscreen? They should be filing IFR even while,staying in the pattern.
 
I wonder why they did not also add ADS-B to it? It seems as with this box, traffic information cannot be received anymore. Not impressed.
 
The initial selling point of stratus and foreflight. Was to avoid extra charges for weather info. So now that I have foreflight and the stratus,why would I want XM?
 
frfly172 said:
The initial selling point of stratus and foreflight. Was to avoid extra charges for weather info. So now that I have foreflight and the stratus,why would I want XM?
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If you do any serious cross country and have not tried out XM weather (I borrowed a friend's Garmin for a July flight from MT to OSH and back) you don't know what you are missing. Sirius said they were working on a deal with Foreflight almost 18 months ago, so nice to see it's finally here. Count me in.
 
A few years ago I took my Sport Cub, with Garmin 496 and XM, on a backcountry Idaho trip with a group of other pilots. We were camped in a remote canyon, with no phone, no internet, no cell service, and no way to see the weather beyond the closest ridge. But the 496 could still "see" the satellites, even on the ground. For three days my Cub was the only source of weather data for the whole group.

Nice, but for my present purposes not worth the extra and recurring costs of XM.
 
scottd said:
[...] Add the Stratus to the picture and you have traffic and AHRS.
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I understand that it is not possible to connect both devices at the same tim. It's either Stratus or XM. Not to speak of the required space on the dashboard.

This doesn't make much sense to me. While XM is certainly nice, I would not want to give up traffic. A StratusXM would have been a much more appealing solution IMHO.
 
scottd said:
[...] However, in ForeFlight you can connect a Stratus via WiFi and get traffic while at the same time connect ForeFlight to an SXAR1 via Bluetooth and receive weather and TFRs.
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Ahh, OK. I stand corrected.
 
That looks like ads-b WX radar though.. I thought Xm was more detailed? Or did you have ads-b radar selected during the screenshot?

scottd said:
Yes, you can connect the two at the same time to ForeFlight...where did you hear you can't? I have been doing it for the last 8 months with no issues. See below. I get traffic and AHRS from the Stratus and weather from the SXAR1. If I were to turn off or disconnect the SXAR1, the Stratus weather would take over and display almost immediately. Both of these units fit into my pocket. I suction-cup mount them on the side/back window out of the way. No wires, although both solutions have external antennae that can be used.

SiriusXM-Traffic.PNG
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OK, I guess for some reason I thought the XM feed would have been like what you receive when on a cellular connection.

scottd said:
The radar shown is from SiriusXM. Not sure what you mean by more detailed? The SiriusXM uses one more color, but the resolution is the same as the regional ADS-B radar. Now SiriusXM has complete coverage updated every 5 minutes across the U.S. whereas the national mosaic from ADS-B is pretty horrible in terms of both spatial and temporal resolution.
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frfly172 said:
The initial selling point of stratus and foreflight. Was to avoid extra charges for weather info. So now that I have foreflight and the stratus,why would I want XM?
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You get what you pay for. You get a higher definition weather radar with XM and in my experience, XM updates a little quicker/more frequently than ADS-B.....but there is certainly a valid debate over whether it is really worth $40 a month.
 
Indiana_Pilot said:
That looks like ads-b WX radar though.. I thought Xm was more detailed? Or did you have ads-b radar selected during the screenshot?
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Maybe it is a FF issue?

XM radar on my Garnim portables is a much higher definition radar picture and looks like what you see on FF when getting your weather on the ground over Wi-Fi or cellular.
 
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So, do you need a special XM antenna for this, or is there a plug adapter to use an existing antenna? I already have an XM antenna and aviation wx subscription, but I not about to shell out another $40 per month for the ability to display it on FF.
 
scottd said:
Qualitatively, you don't add twice as much value to the product by having twice the number of colors to the radar image. Fine tuning the number of dBZ levels presented to the customer is the key to provide the inherent threat without providing unnecessary information.
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It's not the colors I'm talking about, but the definition. The radar depiction I get with XM weather on the Garmin portables has the same level of detail and definition as what I see on FF when I am at home connected to the internet. When you take FF away from the internet and are receiving ADS-B in the air, the pixelation is not very definitive at all.
 
Fearless Tower said:
It's not the colors I'm talking about, but the definition. The radar depiction I get with XM weather on the Garmin portables has the same level of detail and definition as what I see on FF when I am at home connected to the internet. When you take FF away from the internet and are receiving ADS-B in the air, the pixelation is not very definitive at all.
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I find it interesting that the weather expert went immediately to an attenuation resolution when it was mentioned, but the rest of weather layman immediately thought about spatial resolution. @scottd Would you say that as a weather scientist (different from meteorologist?) the attenuation resolution is more interesting?

(Really, if the spatial resolution affects where you fly at this level, I would believe you're using the product in a potentially dangerous fashion, but it'd be interesting to get perspective.)

EDIT, disclosure: I'm a FF and Stratus user. I'm unlikely to get XM as I'm a VFR and mostly fair weather flyer.
 
scottd said:
As I mentioned in an earlier post, you can purchase antennae for the SXAR1 and Stratus. For the SXAR1 there's one for the GPS source and the other for the XM source. But, I have my SXAR1 suction-cup mounted to the window and rarely have seen any issues with reception without the antennae.

To me, having lightning with a high detection efficiency, storm tracks and echo top heights along with a complete radar depiction before I depart is worth the price of the subscription. But as I said earlier, it's not for everyone.
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Got that, but in my case it doesn't seem worth it to do that (pay more just for the ability to put XM on ForeFlight).

I already have a Garmin XM antenna and the subscription, so I can either continue to lug two separate devices to have both XM and ADS-B or I can pay more $$$ just to be able to display on a single device.
 
arnoha said:
(Really, if the spatial resolution affects where you fly at this level, I would believe you're using the product in a potentially dangerous fashion, but it'd be interesting to get perspective.)
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That is certainly a valid point and ADS-B is generally sufficient to keep you out of the bad stuff. Personally, I had XM weather well before FF and ADS-B came out, so I was simply used to a much better picture clarity. But, it comes at a price.
 
Fearless Tower said:
Got that, but in my case it doesn't seem worth it to do that (pay more just for the ability to put XM on ForeFlight).

I already have a Garmin XM antenna and the subscription, so I can either continue to lug two separate devices to have both XM and ADS-B or I can pay more $$$ just to be able to display on a single device.
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Wouldn't you ditch the Garmin subscription if you went with FF? Or do you mean the "more" in reference to the cost of the receiver?
 
arnoha said:
Wouldn't you ditch the Garmin subscription if you went with FF? Or do you mean the "more" in reference to the cost of the receiver?
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To do it all on FF it would require the cost of an additional receiver, apparently.

Right now, my setup is a bit overkill, but I like it. I have FF on my iPads and iPhone and Stratus II. I also have a Garmin Aera that I use in the biplane and a 696 in the Beech 18 with a XM antenna (w/subscription) that can be interchanged between the two airplanes.

In the biplane particularly, I prefer to use the Garmin as my primary since it is running off of ship's power and easier to see/utilize while flying. I turn on the iPad as needed to save battery life on long flights.
 
Huh...thinking about weather radar makes me realize just how complex it could be. Seems to me to be five dimensional, if I understand it correctly (lat, long, tilt, dbZ, time), so it's not a trivial amount of data. Something like XM would need to provide the entire coverage area in a single signal, since I believe the entire area is covered by illumination from a single satellite. Is it just looping? Are different geographic areas on different channels? ADS-B has it a little easier, as one dimension is removed (tilt). Is the time dimension also removed? If I remember correctly, (I rarely use either service in my flying), XM has some history, but I don't know about ADS-B. And on ADS-B, since it's ground based, is the entire US covered in the signal, or only a zone around the transmitter?

Since I don't fly weather currently, I've never really thought about it.
 
One time, at Oshkosh, I saw a new product from Honeywell that is quite interesting.

They are consolidating the feeds from their airborne radars and sending it back to tablets.... They will have cloud tops. How cool will that be?
 
scottd said:
I don't know what you mean by "attenuation resolution."
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You mentioned that there's an additional color on the intensity scale in a previous post. That would suggest that XM has a very slightly higher resolution on the radar attenuation. Maybe I'm getting something wrong. I hardly understand weather radar.

Certainly anti-aliasing could be applied to make the spatial resolution look higher. I'd be curious if the lack of it in FF is an attempt to save the battery life or if there was a product decision that smoothing the signal would be less useful to the pilot.

BTW, though I'm a weather dunce, I share the software engineering background with you. 25 years in this industry and currently working in the messaging space for LinkedIn. (Don't judge me on what's there now. I've only been at the helm for two quarters! :) )
 
scottd said:
I'd probably stick to just four dimensions...no need to bring string theory into it. ;-)

ADS-B and SiriusXM both are receivers that store information based on broadcasts. Miss the broadcast, then you miss the data. ForeFlight (and other apps) store information as it is received (there is some onboard memory). If we wanted, we could store all of the data received from ADS-B or SiriusXM and present a multi-hour loop of the radar, hours of METAR, TAF, PIREP history, etc. Unfortunately, there are limitations with the hardware (iPad or iPhone) and we have to make decisions as to what's optimal for the typical customer. That often means limits are set. By the way, there are multiple Sirius/XM satellites in orbit. Although I believe only two provide weather.
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OK, so the time dimension is device-created. Good to know. I know that when internet connected, I can easily get a time loop. But, as you said, no real bandwidth limitations there.
 
I sure liked using the Baron XM system before I sold the plane. It worked well with FF (and had more smooth borders on the display), prior to FF it worked well with an old Winders tablet that i had (with altitude rated hard drive).

I haven't sold the XM receiver yet, keeps thinking the I may want to use again in the future.

Yeah, it has a few more wires, but if you own the plane it's not a big deal.
 
Tempting, as it would be a good savings by comparison to what I am paying now for my 396 XMWX subscription, but I do note that the SXAR receiver has no provision for Sirius XM audio.

Hmmm.
 
This is a good move. XM weather is much higher resolution compared to ADS-B. Free is nice but you get what you pay for. Left image is XM, middle image is ADS-B regional, right image is ADS-B national. Draw your own conclusions.

3-stratus-radars.jpg
 
SCCutler said:
Tempting, as it would be a good savings by comparison to what I am paying now for my 396 XMWX subscription, but I do note that the SXAR receiver has no provision for Sirius XM audio.

Hmmm.
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Good point. I wouldn't want to give up my in-flight access to Tom Petty Radio.
 
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