Lightning in XM weather

[Paul kgyy]

Someone asked a while back what the source was for the opinion that XM
shows only cloud to ground lightning.

This is explicitly stated in the XM manual that came with my new 396.

[Peter R.]

On 8/14/2007 11:08:09 AM, Paul kgyy wrote:

> This is explicitly stated in the XM manual that came with my new 396.

That was me doing the asking, Paul. Thanks for that. Again, I was curious
from a comparison PoV between XM and WSI, which is the downlinked weather
service to which I currently subscribe.

--
Peter

[Gig 601XL Builder]

Peter R. wrote:
> On 8/14/2007 11:08:09 AM, Paul kgyy wrote:
>
>> This is explicitly stated in the XM manual that came with my new 396.
>
> That was me doing the asking, Paul. Thanks for that. Again, I was
> curious from a comparison PoV between XM and WSI, which is the
> downlinked weather service to which I currently subscribe.

I certainly wouldn't do any equipment changes now since WSI is feeding via
the Sirius sat system & XM is via it's own system. Things are liable to
change one way or the other when they merge.

[Peter R.]

On 8/14/2007 2:19:49 PM, "Gig 601XL Builder" wrote:

> I certainly wouldn't do any equipment changes now since WSI is feeding via
> the Sirius sat system & XM is via it's own system. Things are liable to
> change one way or the other when they merge.

I have no choice but to change equipment here shortly. Most if not all
installed WSI In Flight receivers are still pulling data from WSI's legacy
satellite network. AFAIK (typing as a customer with a focused interest in
this), WSI has yet to begin shipping their new Sirius satellite receivers to
which we must upgrade.

--
Peter

[Gig 601XL Builder]

Peter R. wrote:
> On 8/14/2007 2:19:49 PM, "Gig 601XL Builder" wrote:
>
>> I certainly wouldn't do any equipment changes now since WSI is
>> feeding via the Sirius sat system & XM is via it's own system.
>> Things are liable to change one way or the other when they merge.
>
> I have no choice but to change equipment here shortly. Most if not all
> installed WSI In Flight receivers are still pulling data from WSI's
> legacy satellite network. AFAIK (typing as a customer with a focused
> interest in this), WSI has yet to begin shipping their new Sirius
> satellite receivers to which we must upgrade.

Ouch, I didn't realize they were requireing the change now. That would make
me nervous as hell. What is WSI saying about ther XM/Sirius merger?

[Peter R.]

On 8/14/2007 5:35:57 PM, "Gig 601XL Builder" wrote:

> Ouch, I didn't realize they were requireing the change now.

Yep, required because the legacy system will be deactivated sometime early
2008. All customers must be over to the new receiver by that time.

> That would
> make me nervous as hell. What is WSI saying about ther XM/Sirius merger?

There are a few things about WSI InFlight that have incited my ire since I
have been a customer. Reverse engineering weather on the Garmin GNS430/530
that then resulted in Garmin abandoning WSI and leaving those of us with MX20
moving maps no longer supported starts the list. Frequent service outages and
this mandated upgrade round it out. When the service works it is excellent,
however.

Since XM and Sirius haven't officially merged yet (I think they are being
slowed/stopped by the US gov't, no?) I am confident that WSI will not muddy
the waters by mentioning any more constraints to their customers.


--
Peter

[Peter Clark]

On Tue, 14 Aug 2007 19:03:14 -0400, "Peter R." >
wrote:

>On 8/14/2007 5:35:57 PM, "Gig 601XL Builder" wrote:
>
>> Ouch, I didn't realize they were requireing the change now.
>
>Yep, required because the legacy system will be deactivated sometime early
>2008. All customers must be over to the new receiver by that time.

It should be noted that the KDR510 FIS uplink unit from Bendix/King
has also been obsoleted with 6/08 EOL. Their replacement is the
KDR610 XM unit.

[Peter R.]

On 8/14/2007 7:51:18 PM, Peter Clark wrote:

> It should be noted that the KDR510 FIS uplink unit from Bendix/King
> has also been obsoleted with 6/08 EOL. Their replacement is the
> KDR610 XM unit.

Interesting. What is Bendix doing to transition their customers to this new
unit? Providing the equipment for free? Labor to install it?

--
Peter

[Gig 601XL Builder]

Peter R. wrote:
> On 8/14/2007 5:35:57 PM, "Gig 601XL Builder" wrote:
>
>> Ouch, I didn't realize they were requireing the change now.
>
> Yep, required because the legacy system will be deactivated sometime
> early 2008. All customers must be over to the new receiver by that
> time.
>
>> That would
>> make me nervous as hell. What is WSI saying about ther XM/Sirius
>> merger?
>
> There are a few things about WSI InFlight that have incited my ire
> since I have been a customer. Reverse engineering weather on the
> Garmin GNS430/530 that then resulted in Garmin abandoning WSI and
> leaving those of us with MX20 moving maps no longer supported starts
> the list. Frequent service outages and this mandated upgrade round it
> out. When the service works it is excellent, however.
>
> Since XM and Sirius haven't officially merged yet (I think they are
> being slowed/stopped by the US gov't, no?) I am confident that WSI
> will not muddy the waters by mentioning any more constraints to their
> customers.

From a story on C-Net:

What regulatory hurdles does the deal face?


The U.S. Department of Justice and the Federal Communications Commission
must grant approval, posing a significant challenge. Because Sirius and XM
are the only two satellite radio providers operating in the country, their
merger would effectively create a monopoly. Federal legislation bars both
satellite radio licenses from being owned by the same company to guard
against high prices and other negative effects on consumers. FCC Chairman
Kevin Martin said in a statement that the hurdle for approval would be high.
"The companies would need to demonstrate that consumers would clearly be
better off with both more choice and affordable prices," Martin said. Given
historic opposition to media consolidation by Democrats, who control
Congress, the companies will have some hard lobbying to do.

---



That story was dated back in February. While they are going to have to jump
through hoops I have a feeling that the merger will go through. While it
will form a monopoly as far as satellite delivered radio is concerned it
isn't like satellite is the only way to listen to the radio. Added to that
is the fact that if they don't merge one or both is likely to go belly up
sooner or later.

[Jonathan Goodish]

In article . com>,
Paul kgyy > wrote:

> Someone asked a while back what the source was for the opinion that XM
> shows only cloud to ground lightning.
>
> This is explicitly stated in the XM manual that came with my new 396.

Most weather providers obtain lightning data from the National Lightning
Detection Network, which is operated by Vaisala. The network displays
cloud to ground strikes.

WSI uses data from their own lightning detection network, which can
detect both cloud to cloud and cloud to ground. I'm not sure what their
InFlight product displays.

In any case, both products pale in comparison to sferics devices for
in-flight lightning detection.


JKG

[Andrew Gideon[_2_]]

On Wed, 15 Aug 2007 12:03:41 -0400, Jonathan Goodish wrote:

> The network displays
> cloud to ground strikes.

How does it work that it can discern the difference?

- Andrew

[Peter Clark]

On Wed, 15 Aug 2007 08:02:51 -0400, "Peter R." >
wrote:

>On 8/14/2007 7:51:18 PM, Peter Clark wrote:
>
>> It should be noted that the KDR510 FIS uplink unit from Bendix/King
>> has also been obsoleted with 6/08 EOL. Their replacement is the
>> KDR610 XM unit.
>
>Interesting. What is Bendix doing to transition their customers to this new
>unit? Providing the equipment for free? Labor to install it?

Little to nothing. They're providing the equipment at reduced cost
(pro-rated based on when you purchased it, assuming you have a current
working FIS subscription). Antenna is extra, installation is extra
(and of course you have to yank the headliners out to run the cabling
for the on-top-of-aircraft antenna rather than the underneath FIS
antenna, etc etc etc). Including labor it's looking like around $3500
- $5500 per aircraft to upgrade depending on time since the KDR510 was
purchased. They already turned off the annual subscription option too
so you're down to 30 or 90 day increments with the commeserate
increase in cost over the old annual package. They really want people
off this stuff right now.

Personally I'm going to a GMX200 and GDL69A in my Malibu when the time
comes this fall. I'm going to have it done as part of the dual 530W
upgrade (since everything has to be ripped apart anyway, Piper didn't
put the good enough the GPS antenna wiring in when it was
manufactured) once Meggitt/S-Tec comes out with the MAGIC software
update. Haven't decided what to do with the Cessnas yet.

[Peter R.]

On 8/15/2007 4:34:45 PM, Peter Clark wrote:

> Little to nothing. They're providing the equipment at reduced cost
> (pro-rated based on when you purchased it, assuming you have a current
> working FIS subscription). Antenna is extra, installation is extra
> (and of course you have to yank the headliners out to run the cabling
> for the on-top-of-aircraft antenna rather than the underneath FIS
> antenna, etc etc etc). Including labor it's looking like around $3500
> - $5500 per aircraft to upgrade depending on time since the KDR510 was
> purchased.

Wow, it seems that B/K is making a customer's decision to move over to XM or
WSI a bit easier.

--
Peter

[Danny Deger]

"Jonathan Goodish" > wrote in message
...
> In article . com>,
> Paul kgyy > wrote:
>
>> Someone asked a while back what the source was for the opinion that XM
>> shows only cloud to ground lightning.
>>
>> This is explicitly stated in the XM manual that came with my new 396.
>
> Most weather providers obtain lightning data from the National Lightning
> Detection Network, which is operated by Vaisala. The network displays
> cloud to ground strikes.
>
> WSI uses data from their own lightning detection network, which can
> detect both cloud to cloud and cloud to ground. I'm not sure what their
> InFlight product displays.
>
> In any case, both products pale in comparison to sferics devices for
> in-flight lightning detection.

The engineer in me is dying to know how the sensors knows the difference
between cloud to ground and cloud to cloud. Anybody know.

Danny Deger
www.dannydeger.net


>
>
> JKG

[Vaughn Simon]

"Jonathan Goodish" > wrote in message
...
> Most weather providers obtain lightning data from the National Lightning
> Detection Network, which is operated by Vaisala. The network displays
> cloud to ground strikes.

Thanks! I just learned something. You can get a free lightning map here:
https://thunderstorm.vaisala.com/tux/jsp/explorer/explorer.jsp
It is for the entire USA, and only updated every 20 minutes, so you can hardly
use it to pick your way through the cells, but it could sure help you decide if
it is healthy to go flying.

[Blueskies]

"Danny Deger" > wrote in message ...
>
> The engineer in me is dying to know how the sensors knows the difference between cloud to ground and cloud to cloud.
> Anybody know.
>
> Danny Deger
> www.dannydeger.net
>


Polarity? Maybe something with the pulse shape?

[w_tom]

On Aug 15, 8:16 pm, "Danny Deger" > wrote:
> The engineer in me is dying to know how the sensors knows the difference
> between cloud to ground and cloud to cloud. Anybody know.

Cloud to ground lightning creates a unique RF signature. By
recording these radio waves and by using time from GPS satellites to
corrdinate those receptions, then the NLDN could pinpoint those ground
strikes. When too many ground strikes occur, the network tends to
become overloaded; does not detect all strikes.

Then the NY Times made some inquires in response to a lightning
strike in the area of the former WTC that killed one person. Direct
lightning strikes known to have hit both the WTC and Empire State
Building (on average 25 and 40 times annually) were not detected;
apparently did not create that RF signature. No followup information
is available as best I can tell.

[Morgans[_2_]]

"w_tom" > wrote

> Cloud to ground lightning creates a unique RF signature. By
> recording these radio waves and by using time from GPS satellites to
> corrdinate those receptions, then the NLDN could pinpoint those ground
> strikes. When too many ground strikes occur, the network tends to
> become overloaded; does not detect all strikes.

In a gross simplification, cloud to ground flashes produce disturbances in
the LF and VLF EM bands. They are received over very long distances, so
they are easier to get a map of over a complete region, even with a sparse
location of sensors. Probably why it is desirable.

Cloud to cloud flashes are mainly in the VHF range, and therefore are line
of sight.

For a very complete explanation, see
<https://www.thelightningpeople.com/htm/about/events/ildc/ildc2000/docs/03_CUMMINS.pdf>
--
Jim in NC

[w_tom]

On Aug 17, 2:35 am, "Morgans" > wrote:
> In a gross simplification, cloud to ground flashes produce disturbances in
> the LF and VLF EM bands. They are received over very long distances, so
> they are easier to get a map of over a complete region, even with a sparse
> location of sensors. Probably why it is desirable.
>
> Cloud to cloud flashes are mainly in the VHF range, and therefore are line
> of sight.

Now explain why the system saw no strikes when 25 and 40 direct
lightning strikes hit the Empire State Building and WTC annually. I
have long been waiting for that answer. Do strikes to tall buildings
not create LF and VLF EM radiation?