wx500 vs gdl69a weather & flight charts vs chartview

skidoo

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skidoo
Hello, after 30+ years of no flying, I purchased a T182T with g1000. I took additional risk because I'm not sure what I should have in the options. So, I am wondering what is the main differences between the stormscope wx500 and the GDL69A weather systems and also the differences between Garmin's Flite Charts and Jepp ChartView systems. Any insight would be appreciated!
 
The GDL69A is a XM radar down-link. Basically you'll get NEXRAD radar for the entire country. Keep in mind that it is delayed and shouldn't be used too close to thunderstorms because of that delay.

The stormscope detects lightning strikes and displays their approx. location from where you're at. It can provide some more "current" data than the XM system but not as complete of a picture.

Personally, I'd take both if I could have both.

As far as the differences between the chart systems..no idea.
 
Garmin Flitecharts are electronic versions of the NACO approach plates. They are not georeferenced so all you can do is read them on the screen. Jepp's Chartview gives you electronic versions of the Jepp plates. They are georeferenced so you can see your airplane flying around on the plan view. You can also see yourself taxiing around on the airport diagram.
 
Garmin Flitecharts are electronic versions of the NACO approach plates. They are not georeferenced so all you can do is read them on the screen. Jepp's Chartview gives you electronic versions of the Jepp plates. They are georeferenced so you can see your airplane flying around on the plan view. You can also see yourself taxiing around on the airport diagram.

Your comments are true, but with or without ChartView, the G1000 has SafeTaxi that displays aircraft position on the airport taxiway system. Garmin now indicates that next year they will be Geo-referencing the NACO charts, at least on the GPSMAP 696. ChartView also has better chart presentation format choices including one key selection of plan view, profile view, minimums, and briefing strip.
 
Lightning strike data is also available via the GDL-69A, but it costs more (it's on the $50/mo Aviator but not the $30/mo Aviator LT). In addition, the radar and lightning data from XM weather can be several minutes old. An on-board radar or sferics device (like the WX-500) gives real-time data. If you do a bit of searching on the web, you can find a lot of information on the differences (including strengths and weaknesses) of sferics devices versus radar data. Optimally, you want both, as comparison of the two can be very enlightening. The absence of lightning (what sferics sees) doesn't always mean an acceptable ride, the presence of heavy precip (what radar sees) doesn't always mean you can't safely go through, and the abssence of heavy precip doesn't always mean there isn't convective activity.

BTW, the "storm cell" data on XM weather provides good information on building convective activity that may not have reached the stage of showing up as "bad" on sferics or radar.
 
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To elaborate on Jesse's comments WRT the WX500 and XM weather, the WX500 is an example of a "Spherics" device that uses a directional antenna to receive the "static" produced by electrical discharges in thunderstorms. Unlike most such devices the WX500 has no display and is intended to be used with a separate MFD like the GMX200. The WX500 is one of the most recent designs and thus should be one of the most effective spherics receivers avallable. That said all airborne spherics devices suffer from two significant limitations. One is that the range information is generated by comparing the strength of the received "static" with a "standard model". IOW a strong signal will be displayed close to the aircraft and a weak signal will be displayed further out. Since the actual intensity of RF emitted by a thunderstorm varies greatly from cell to cell and strike to strike, this range information is often very inaccurate. A common symptom called "radial spread" makes the display of discharges from a single cell spread out along a line drawn through the airplane and the cell. For a single cell this isn't too big a problem but when there are lots of TRW in range the result can be pretty confusing.

The other major limitation is that these devices are fairly useless at close range (within 25 nm of a cell or area of TRW) because in that case the display will often be saturated with strike indications scattered all around. I believe that the main cause of this is the reflection of TRW generated RF from the ground which creates "ghosts" of the actual discharges. Bottom line on that is the recommendation by the makers of all spherics receivers to remain at least 25 nm from any indications on the display. This might not seem like a big deal since no one really wants to get too close to a thunderstorm but this does relegate the users of such units to being unable to penetrate an area or line of TRW safely that would otherwise be navigable. As a result stormscopes are best utilized as a "strategic" tool for completely avoiding areas of TRW. The also offer much appreciated comfort/security when flying in IMC where TRW may or may not be present.

XM weather (ala GDL69) receives weather data from the XM geostationary satellites that is prepared and uplinked by a group of ground stations. There is a subscription fee for this data ranging from $30/month to something like $100/month with the higher fee service providing more data. The basic service includes the most popular data: a NEXRAD composite image for the whole continental US. along with textual data like METARS and TAFs. Moving up to the next level ($50/mo) adds winds aloft, AIRMETS/SIGMETS, lightning (more on that later), Canadian weather radar, satellite cloud images, and stuff like cell tops/tracks, freezing levels and PIREPS. The most expensive service adds some additional information on hurricanes, predicted icing conditions, and turbulence.

Keep in mind that a particular combination of XM receiver and display (MFD) often limits the user to less than the full offering of a particular service. For instance my EX500 MFD coupled to a HeadsUp receiver won't display the text of AIR/SIGMETS making the grapical display far less useful than it could be and I can't display any of the extras included in the most expensive service level.

XM's lightning product is generated by a network of widely separated ground receivers which makes the location depicted for each strike very accurate but this system only "sees" cloud to ground strikes while the airborne stormscopes display both cloud to ground and cloud to cloud discharges and the cloud to cloud type is far more prevalent in the early stages of TRW development, often preceeding the release of precipitation and is considered to be well correlated with turbulence.

All the XM products suffer from "data aging" which makes the information less "real time" than an onboard spherics receiver or radar unit. METARS are transmitted every 20 minutes but the combination of occasional reception problems and ground data delivery issues often results in METARS that are 30-90 minutes old. Most important, the NEXRAD images will be anywhere from 5-15 minutes "old" with the "age" of one portion different than a nearby portion. In addition, the displayed precip intensity often doesn't correlate well with actual precip reaching the ground due to the fact that the actual NEXRAD stations "see" with varying accuracy (there are blind spots overhead and the base of the coverage rises with distance from the station due to the upward aiming of the antenna and the curvature of the Earth). Also in many cases XM NEXRAD is overly conservative showing significant precip that's not actually falling from the clouds but simply pent up inside them at an altitude much higher than you may be flying. Finally the computer program that melds the multiple NEXRAD site images into a single one has to fllter out the "ground clutter" from each site and occasionally that effort removes indications of real precip. This means that relying on XM NEXRAD to keep you clear of TRW and heavy rain isn't anywhere near infallible, which is one reason why having both XM and a stormscope is advantageous to only having one or the other.
 
What lance said - which is a reason for both. Now I flew with just a stormscope in the Mooney, and it was decent at telling you when you were within 25 NM of stuff with which you didn't want to close.

With Both, you get to map the stormscope (realtime) strike data against the NexRad (delayed) data, and get an idea of storm motion. If you head to an area that's clear to BOTH sources, then that's generally a good choice.
 
Thanks for the replies!

Well, I finally obtained the POH manuals out of the T182T. In looking at the manual, it lists some standard equipment for the G1000 NavIII, and the WX500 is listed. The T182T was advertised with the GDL69A Weather satellite, but had no mention of the Wx500. So, how do I tell if it actually has it on board?
 
Just ask the owner. If you look at the airplane, it will have an antenna on it that has stormscope engraved on it. The G1000 map page, use the weather options to determine if the WX500 is installed.
 
The G1000 system comes with the Stormscope and XM Wx through the GDL69. That's the package. You have to subscribe, through XM, to get the downlink WX, but the capability is there. Stormscope is always there, no activation req'd.

Are you buying new or used? If used, find out whether the owner activated either the Garmin FliteCharts or Jepp Chartview. I forget what it costs just to turn that on, but IIRC it was something like $2500 just to activate, then you have to subscribe (kind of like a personal seat license for football.:nonod:).

FliteCharts are cheaper than Chartview. The lack of geo-referencing is a downside vs the Jepp. Otherwise, if you already use NOS charts, and don't care about the geo-referencing (which is a great supplement to situational awareness) save money and go with Garmin. Personally, I prefer Chartview. I had Flitecharts in my T182T, and I have Chartview in the Matrix.
 
The G1000 system comes with the Stormscope and XM Wx through the GDL69. That's the package. You have to subscribe, through XM, to get the downlink WX, but the capability is there. Stormscope is always there, no activation req'd.

Are you buying new or used? If used, find out whether the owner activated either the Garmin FliteCharts or Jepp Chartview. I forget what it costs just to turn that on, but IIRC it was something like $2500 just to activate, then you have to subscribe (kind of like a personal seat license for football.:nonod:).

FliteCharts are cheaper than Chartview. The lack of geo-referencing is a downside vs the Jepp. Otherwise, if you already use NOS charts, and don't care about the geo-referencing (which is a great supplement to situational awareness) save money and go with Garmin. Personally, I prefer Chartview. I had Flitecharts in my T182T, and I have Chartview in the Matrix.


Great! I read in the POH that the stormscope is standard equipment, but I can't get out to it to see for myself because it is presently stuck 400 miles away due to icing weather.
 
Great! I read in the POH that the stormscope is standard equipment, but I can't get out to it to see for myself because it is presently stuck 400 miles away due to icing weather.

What yr is the 182?
 
Ah ha, that's the year I had. Sorry, no WAAS unless you stump $20-25k for the upgrade. That also means you can't get synthetic vision, until you stump for the WAAS. No big deal, but if you were thinking about it that's what you'd be facing.

A T182T with the G1000 is a phenomenal aircraft. You will love it.
 
New hear and wanted to thank everyone for all the great posts.

I recently bought a 2000 T206H and is has a BFG Skywatch TAS and an MX20. I'm considering putting a weather system in it. I live in Socal and fly to the sierra's a lot. So I'm considering getting a weather system of sort. If I were to get only a single system what would probably be the best way to go? I understand there is a pluses and minus's to both but if you could choose one system to hookup to my setup what would you suggest?

Thanks for the advice in advance.
 
New hear and wanted to thank everyone for all the great posts.

I recently bought a 2000 T206H and is has a BFG Skywatch TAS and an MX20. I'm considering putting a weather system in it. I live in Socal and fly to the sierra's a lot. So I'm considering getting a weather system of sort. If I were to get only a single system what would probably be the best way to go? I understand there is a pluses and minus's to both but if you could choose one system to hookup to my setup what would you suggest?

Were it my money, probably a Garmin Aera 510 or 560.

IMHO, while the NEXRAD datalink is a bit slower than on-board radar or stormscope, it gives you information for a much wider area and the weather datalink offers many products besides just the radar. Having the portable unit also gives you a backup in case of an electrical failure on your airplane.
 
Were it my money, probably a Garmin Aera 510 or 560.

IMHO, while the NEXRAD datalink is a bit slower than on-board radar or stormscope, it gives you information for a much wider area and the weather datalink offers many products besides just the radar. Having the portable unit also gives you a backup in case of an electrical failure on your airplane.

I'm really looking for something to tie into my MX20 and from what I can see this won't seem to do that. Am I missing something?
 
I'm really looking for something to tie into my MX20 and from what I can see this won't seem to do that. Am I missing something?

Nope. If you're looking to feed your MFD, you want the (more-expensive) GDL 69A: https://buy.garmin.com/shop/shop.do?cID=196&pID=228

The portable simply gives you the info on another screen that's not dependent on your aircraft's electrical system, for a fraction of the price of the datalink box. However, it's cool to have the toys in your panel do everything too. :yes:
 
I'm really looking for something to tie into my MX20 and from what I can see this won't seem to do that. Am I missing something?
Generally with a certified aircraft the FAA will not allow a non-approved data source to be tied into installed equipment so your choices for feeding a MX20 are limited to the more costly TSOd stuff.
 
I'm really looking for something to tie into my MX20 and from what I can see this won't seem to do that. Am I missing something?

The logic goes something like this: If you'll be flying IFR, you want a back-up GPS anyway. Might as well have it do something other than be a pretty face in the panel (or on the yoke) - displaying weather is a good chore for it. Any of the portables that support XM will do the trick and will be a lot more economical than the installed cost of a GDL69. The portables also give you more weather data than the MX20 will support - the wx display on the MX20 only goes out 200NM and does not include many of the newer weather products: satellite view, freezing levels, hurricanes etc. I have a GDL69 driving an MX20 and find that I use the weather display on my 496 much more.

Save your pennies for upgrading the MX20 to a GMX200 and put ADS-B on it. That'll give you two independent weather sources (one of which works on the ground.)
 
Sorry to butt in. I'm new at the chat stuff. I'm looking for help from someone who has experience with a G500 / G600 with the Jepp georeferenced approach plates. Anyone? Anyone? Bueller?
 
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