Charlie has great advice here. We could probably cut
the IVP accident rate by 40% if we just stayed out of thunderstorms
and towering Cu. You are NOT going to fly over these monsters. Not in
a IVP-not ever. So your options are to use your nexrad to plot an end
around the lines that develop in the summer or stay below the bases
and avoid the rain shafts.
You should not be using NEXRAD to fly between cells that you
cannot visually see. You have to be VFR to stay safe when operating
close to these things. Some of them are moving at over 60 knots. So if
you have a time lag of up to 10 minutes the cell may be ten miles away
from where it is depicted or more. As Charlie said, the NEXRAD tells
you the direction of movement, which is very important in your
decision making. Stay upwind of these things or plan a very wide
excursion if you have to go on the downwind side.
Descisions to go between cells in a line should not be taken
lightly. Can you see all the way through the break to blue sky on the
other side? How wide is the break between cells? Is the break opening
or closing? How can you tell? What are the tops of the cu in
the break? What is on the other side? Another cell? Is there any
lightning close? What is you escape route if you poke your nose in it
and it closes up?
I fly with WSI on my Chelton and XM on my Garmin 396 (belt and
suspenders). There are differences between the two nexrad images
that are important. One may be painting orange while the other is
green. I choose the most conservative route of the tow shown.
If you are planning on a trip outside the continental U.S. say
Canada or Alaska or the Bahamas-- the coverage does not extend very
far outside of CONUS. Two Lancairs found that out the hard way--both
fatal, one this year.
I was on the other side of the storm that Tom Brady flew into. I
landed in St. Louis twenty minutes before he went down. Ten to fifteen
minutes after I landed the storm passed and the tornado sirens went
off. Tom Brady flew into that. I talked to the FSDO here about his
accident -- his wreckage was scattered over four miles. He was flying
in the low FL 20's when he penetrated the storm.
Living in St. Louis has made every trip this year one with
thunderstorms. I have not topped one yet.
Be careful out there!
Jeff
In a message dated 7/12/2008 7:47:29 P.M. Central Daylight Time,
charliekohler@yahoo.com writes:
Hi Colyn,
IMHO the safest approach to summertime towering cumulus is to
stay VMC. On top- is best if the air is not electrically charged --
if not able-- go down to 3000 feet-- below the bases (VMC) (check
terrain clearance)-- and always be vigilant for lightning and hail
on the downwind side--
yes--stay out of the green (if only to
protect your paint).
And in regards to diversions-- go early when the heading
corrections are 10 to 20°. Not when you're in a box canyon and you
need a 90° to a 180° course change. You'll notice that large holes
and openings from 100 miles out will close up by the time you get
there. And it would've been better to take that 20° heading cut to
go around the up wind side before you got there. Saves time too.
And
Thanks--
Charlie K.
-----
Original Message ----
From: Colyn Case at earthlink
<colyncase@earthlink.net>
To:
lml@lancaironline.net
Sent: Saturday, July 12, 2008 5:11:54
PM
Subject: [LML] Re: Accidents
Charlie, thanks for this.
Are you proposing no IMC up high period
or just staying 2X recommended distance from what you see on
xm? (maybe even staying out of all green if you are high and
imc).
Colyn