VFR "picking his way thru" heavy cells with XM Radio weather

On Wed, 6 Jun 2007 10:50:09 -0500, "Dan Luke"
wrote in
:


"Larry Dighera" wrote:

That's what XM WX is for, praised be its name!

Some information is better than none, even if it is stale.

Have you used it?


No.

"Larry Dighera" wrote:


That's what XM WX is for, praised be its name!

Some information is better than none, even if it is stale.

Have you used it?


No.

Then, with respect, you have little practical information on which to judge
its value in operational situations. "Some information is better than none"
does not do justice to the superb weather awareness it provides. It is far
superior to using ATC/Fligh****ch.

As to the "stale" business, in 200+ hours of using the product in the most
thunderstorm-infested region of the U. S., I have found 6-8 minute maximum
lag a non issue for avoiding CBs.

--
Dan

"The future has actually been here for a while, it's just not readily
available to everyone."
- some guy at MIT

On 6/6/2007 4:16:53 PM, "Dan Luke" wrote:

As to the "stale" business, in 200+ hours of using the product in the most
thunderstorm-infested region of the U. S., I have found 6-8 minute maximum
lag a non issue for avoiding CBs.

For strategic avoidance I agree but it still requires some thought. My
Bonanza is equipped with WSI downlinked weather displayed on an MX-20 moving
map, and WSI's refresh rates are normally 0 to 4 minutes old. I was under the
impression that NEXRAD could be up to five minutes old before being uplinked
to the delivery satellites (corrections appreciated). Therefore a worst-case
scenario is that the NEXRAD returns I see on my moving map could potentially
be up to nine minutes old.

At a groundspeed of 50 knots (my guess as to the average speed for a more
severe thunderstorm), nine minute-old data translates to about an 8 nautical
mile area ahead of the mature storm's direction as depicted on the moving
map. Thus, I add 8 nm to the recommended 10 to 20 nm (depending on storm
severity and type - frontal) to cover that lag time, assuming haze or IMC
prevents seeing the storm out the window.

What concerns me are those days where t-storms seem to be popping up
everywhere and returns go from light to intense in 15 minutes or less. In
those cases this relatively slow refresh rate makes flying through that zone
a bit of a butt clencher.

--
Peter

"Peter R." wrote:

What concerns me are those days where t-storms seem to be popping up
everywhere and returns go from light to intense in 15 minutes or less. In
those cases this relatively slow refresh rate makes flying through that zone
a bit of a butt clencher.

Indeed.

Experience and caution are necessary components in making optimum safe use of
the tool. After a while one develops a sense of what the NEXRAD is saying.
The time sometime comes when discretion is the better part of valor, and a
land-and-wait decision becomes the prudent course. However, since I've had XM
weather I've had a lot better information on which to base that decision, and
I've only had to make it once.

--
Dan
? at BFM

("Dan Luke" wrote)
As to the "stale" business, in 200+ hours of using the product in the most
thunderstorm-infested region of the U. S., I have found 6-8 minute maximum
lag a non issue for avoiding CBs.


RV-10: Cruise Speed .....200 (3+) miles/minute

"It's like he flew right into the storm, as if he didn't no that it was
there," one witness reported. g


Montblack

know

know

Thanks. I thought you were commenting on the lack of Japanese theater
in the cockpit.

Jose
--
There are two kinds of people in the world. Those that just want to
know what button to push, and those that want to know what happens when
they push the button.
for Email, make the obvious change in the address.

"Montblack" wrote:

As to the "stale" business, in 200+ hours of using the product in the most
thunderstorm-infested region of the U. S., I have found 6-8 minute maximum
lag a non issue for avoiding CBs.


RV-10: Cruise Speed .....200 (3+) miles/minute

OK, rub it in. Poor ol' Delta was doing the best she could.

Anyway, I'm beyond the reach of RV-10 temptation now. The deal for my next
airplane is almost done.


"It's like he flew right into the storm, as if he didn't no that it was
there," one witness reported. g

If the witness could see it, why couldn't the pilot?

--
Dan
? at BFM

"Dan Luke" wrote

Anyway, I'm beyond the reach of RV-10 temptation now. The deal for my
next airplane is almost done.

Man, you can't leave us hangin' like that! What kind of airplane?
--
Jim in NC

"Morgans" wrote:

Man, you can't leave us hangin' like that! What kind of airplane?

T182T

--
Dan
? at BFM