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View Full Version : WX500 Stormscope/G1000


N666LG
28th Jul 2010, 13:01
A couple of days ago I was IFR from UK to South West France, weather had indicated some isolated CBs and I was in and out of cloud at FL100, nothing on the Stormscope in my path, nothing high that I could see, one or two strikes off my left wing about 50 miles away, it was in strike mode. I popped out of cloud briefly and entered another cloud that had a top of around 13000, looked a bit dark but nothing on the scope so went in. Within seconds my headset was off and alarmingly on the scope there were maybe a couple of dozen strikes all around me. There seemed to be less of my right wing so I turned and was out in around a minute, a bit rattled. During the following minutes the strikes on the scope faded and I continued staying out of the way of anything similar. I've gone through the pilots manual for the WX500 and can't find anything to explain the sudden appearance of these strikes, if anyone has any ideas regarding this I'd like to hear them.

Regards

S-Works
28th Jul 2010, 13:23
The Stormscope only shows active electrical energy. That is random so it is perfectly normal for it to show up suddenly as the activity in the cell changes.

IO540
28th Jul 2010, 13:34
The utility of a stormscope (I have the WX500 too, driving a KMD550 MFD) for avoidance of hazardous wx while flying in IMC is limited.

It should stop you flying into something that is going to take your wings off, because the biggest updraughts are claimed to generate the most strikes, but anything below that level of turbulence is pretty variable in its electrical visibility.

If I was in IMC and totally stuffed, with TS activity around, I would use the scope to get out of there, but it's not good enough for routine use enroute.

Wot you need is a plane with a decent operating ceiling to do the enroute section in VMC, which means oxygen or pressurisation :) and some web resources to estimate the cloud tops before you go flying.

Also, speaking of a "cloud" with a top at 13k, that was probably a reasonably mean CU/TCU and one can get quite adequately shook up inside one of those, anywhere. You need to play a long game enroute and avoid all that stuff.

It is also quite feasible for a buildup to go "electrical" quite suddenly. A friend of mine was flying along (in IMC ;) ) and reportedly within a few seconds the whole scope lit up like a xmas tree - all around him. A few seconds later he was in severe turbulence.

Fuji Abound
28th Jul 2010, 13:45
Your entering the top of a pregnant CB probably initiated the activity.

NazgulAir
28th Jul 2010, 13:59
It is also quite feasible for a buildup to go "electrical" quite suddenly. A friend of mine was flying along (in IMC http://images.ibsrv.net/ibsrv/res/src:www.pprune.org/get/images/smilies/wink2.gif ) and reportedly within a few seconds the whole scope lit up like a xmas tree - all around him. A few seconds later he was in severe turbulence.
This kind of thing -- the whole scope suddenly flaring up -- can happen, but it shouldn't be totally unexpected. That kind of phenomenon arises out of a precondition that should be well known to the briefed pilot.

IO540
28th Jul 2010, 14:08
i cud do wiz som edukation ere.

Fuji Abound
28th Jul 2010, 14:35
Maybe we are all about to get a lesson.

wigglyamp
28th Jul 2010, 18:47
The WX500 doesn't display storm data within 25 miles of you - only out from 25 NM to 200NM.

IO540
28th Jul 2010, 18:57
The WX500 can't tell the distance anyway, really. It uses some simple analysis of the return intensity, plus some kind of spectral dispersion, to have a stab at it.

I have often flown towards one single huge CB, about 50nm away, at say FL180, with vis of about 200nm all around, and it showed the strikes accurately on azimuth but well dispersed in the distance being depicted, from say 20nm to 100nm. I've got some great photos of just that.

It is very useful all the same, if you get stuck into something. The rest of the time it is great for scaring passengers :)

Fuji Abound
28th Jul 2010, 20:21
I thought these were some good photos of aircraft induced strikes:

Lightning Vs Aeroplanes (http://www.environmentalgraffiti.com/featured/lightning-vs-aeroplanes/12402)

I recently read a good research paper on aircraft induced lightning in developing CBs. I would like to reproduce it here but unfortunately it is copyright. It is an interesting subject and clearly entering a developing CB at the "wrong" time is not a good idea.