Entering cloud - is Stormscope adequate?

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Hop Harrigan
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Entering cloud - is Stormscope adequate?

Unread post by Hop Harrigan » Sun Apr 17, 2016 12:18 pm

Does a Stormscope give adequate information regarding what to expect upon entering cloud? If my Stormscope is not showing any lightning activity, how much turbulence can I expect to encounter. I do not have a Wx Radar on board and am unpressurised, so flying around FL100. Clearly, if the cloud is black and has a huge anvil on top I'm going to avoid it like the plague, but what if you're already in the clag and can't see the tops?
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Re: Entering cloud - is Stormscope adequate?

Unread post by Sardine » Sun Apr 17, 2016 1:23 pm

Hop Harrigan wrote:Does a Stormscope give adequate information regarding what to expect upon entering cloud? If my Stormscope is not showing any lightning activity, how much turbulence can I expect to encounter. I do not have a Wx Radar on board and am unpressurised, so flying around FL100. Clearly, if the cloud is black and has a huge anvil on top I'm going to avoid it like the plague, but what if you're already in the clag and can't see the tops?
Doubt it.

We have a Kodiak equipped with only a stormscope and no weather radar. The stormscope often shows 'lightning' activity on a perfectly clear day. On other days with rain and cloud and hectic turbulence in the vicinity, the stormscope has been clear.
I even have a photo of the lightning bolt right over my destination, but looking out the window, it was clear (and of course, I can't find the photo).

Stormscopes, as I understand, detect static. That could be in clear air, cloud, rain. When I am bored I set it to maximum range to pick up the static from the sand storms to the south of Maun.
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Re: Entering cloud - is Stormscope adequate?

Unread post by Hop Harrigan » Sun Apr 17, 2016 2:08 pm

Hi Sardine,
Mine seems to perform reliably, to the point of seeing a strike on the horizon and then seeing it appear on the scope. But my concern is if the scope shows no activity in a cloud ahead, what am I likely to experience on entering it?
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Re: Entering cloud - is Stormscope adequate?

Unread post by Fransw » Sun Apr 17, 2016 2:22 pm

All I know is that it can be dry inside a cloud just before the rain. That dry condition can send the 'wrong' info to the storm scope that all is clear when its not.. But don't take my word for it, I'm only here to learn.
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Re: Entering cloud - is Stormscope adequate?

Unread post by Iceberg » Sun Apr 17, 2016 4:18 pm

My storm scope has saved my bacon many times. Sure it is not radar, but if it works properly it is very useful.

The behaviour Sardine mention of his scope is not normal. I would have it checked out. Could be a short somewhere in the electrical system giving the false readings.

I don't have radar either. So if CB's are forecast, I either:
1.Fly below the cloud base to be able to see any lightning/rain shafts.
2.If there is broken stratocumulus with embedded CB's, fly on top of it if not too high and then use visual cues to sidestep any CB's.

If I cannot do 1. or 2. I don't fly. If you want to weave through CB's in IMC you need radar and a capable aircraft.
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Re: Entering cloud - is Stormscope adequate?

Unread post by Wildcat_003 » Sun Apr 17, 2016 4:32 pm

Hop just read my comments under "Instrument flying training".......rather stay out of IMC. Prevention is better than trying to cure your problem. With IMC conditions you need proper equipment.
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Re: Entering cloud - is Stormscope adequate?

Unread post by Brand » Sun Apr 17, 2016 5:45 pm

This discussion reminds me: some 10 years ago a good friend of mine phoned around 9pm on a Thursday evening, wanting to know if he can pop in for a VERY stiff drink...

Turns out he and another CPL just landed at Wonderboom. They were inbound from Zambia in a Chieftain (a charter with some tourists in the back) when the storm scope indicated some bad weather.

So they picked what they thought was the safest route through the weather and told the passengers to strap as tight as they can...

To make a long story short , after landing two passengers were bleeding from bumping their heads and the aircraft had to be checked out for structural damage.

He said that he started "sweating" bullets when his flight bag hit the roof and stayed there for about 30 seconds....

Bottom line - nobody that has experience with the wrong thunderstorm, is alive to tell us about it...
Attitude determines Altitude - in Flying and in Life........

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Re: Entering cloud - is Stormscope adequate?

Unread post by kleyn » Sun Apr 17, 2016 6:39 pm

I fly since 1998 and do a lot of cross country flights. I will not fly without a storm scope. I believe a storm scope is not for flying through bad weather concerning thunderstorms but rather to guide you to stay out of it. If your storm scope is working properly you it will show any significant discharge in a 200nm radius. That will give you adequate time to decide what your options are.
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Re: Entering cloud - is Stormscope adequate?

Unread post by Sardine » Sun Apr 17, 2016 7:53 pm

Hi Hop,

Don't get me wrong, ours is also accurate. But it can give misleading readings based on the conditions.
Iceberg wrote:My storm scope has saved my bacon many times. Sure it is not radar, but if it works properly it is very useful.

The behaviour Sardine mention of his scope is not normal. I would have it checked out. Could be a short somewhere in the electrical system giving the false readings.

I don't have radar either. So if CB's are forecast, I either:
1.Fly below the cloud base to be able to see any lightning/rain shafts.
2.If there is broken stratocumulus with embedded CB's, fly on top of it if not too high and then use visual cues to sidestep any CB's.

If I cannot do 1. or 2. I don't fly. If you want to weave through CB's in IMC you need radar and a capable aircraft.
Iceberg, that should be a "her", not "his" :wink:

The readings I mention occur in the south, over the pans, on days with very dry(like, drier than normal) air.

Just because there are clouds and/or a bit of rain, doesn't necessarily mean enough static is being generated to trigger the stormscope.
As I understood it, air moving in opposite directions can cause enough static to be indicated on the scope, under the 'right' conditions. But I have never thought to attempt to use the stormscope to pinpoint areas of turbulence.

While it is definitely a great tool to have, it has its limitations; normally the Nut connecting the yoke to the rudder pedals is the biggest limitation.

Cheers
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Re: Entering cloud - is Stormscope adequate?

Unread post by Iceberg » Mon Apr 18, 2016 8:48 am

Some info on how stormscopes actually work:

https://en.wikipedia.org/wiki/Lightning_detection

The static discharges (lightning) cause a range of electromagnetic waves including visible light and a wide range of radio waves.
Radio waves of different wavelength attenuate differently over distance - this can be used to determine the distance of the strike.
A loop antenna can be used to determine the direction - in the same way as an ADF works.
Anyway, that is how I understand it. Static discharges in dry air as Sardine mentioned can also trigger the scope.
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Re: Entering cloud - is Stormscope adequate?

Unread post by apollo11 » Mon Apr 18, 2016 7:02 pm

I think one has to also make the distinction between hard and soft IMC, many IF holders from recreational and GA point of view will not use the rating to even think to circumnavigate convective activity and or potential icing conditions.

Many IF holders such as above will rather file IFR notably on bad viz days but even on good viz days as it is certainly arguably safer being on an IF flight plan and often use the rating to climb through low level stable cloud get on top and let down in stable IMC conditions at worst.

Storm scope on board no way I'm going to stuff around anywhere near convective weather or known icing.

I think Wildcats advice is sobering and on the money, whilst undergoing IF training a few years ago I go caught in some weather, on a xcountry dual IF flight (one has to fly a 250 NM xcountry under IFR as part of the rating for FAA) it was the most unpleasant experience, never again. It really scared me.
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Re: Entering cloud - is Stormscope adequate?

Unread post by Chalkie » Mon Apr 18, 2016 8:40 pm

Fransw wrote:All I know is that it can be dry inside a cloud just before the rain. That dry condition can send the 'wrong' info to the storm scope that all is clear when its not.. But don't take my word for it, I'm only here to learn.
Sorry Frans. The problem with a thread such as this is one willing to learn can be lead astray by the words of others.

It can never be 'dry inside a cloud' as a cloud always contains moisture.

A Stormscope only picks up electrical energy/turbulence. During a developing towing Cu phase, the Stormscope might show nothing at all, as all the air is moving upwards. Once the airmass starts the upwards/downwards movement of air the Stormscope will pick up the electrical energy and display info of turbulence or lightening strikes.

You need to understand one thing. Weather RADAR is weather avoidance RADAR.

Similarly: The info displayed by a Stormscope is WEATHER AVOIDANCE info.

It is NOT: Pick-your-way-through-little-gaps-between-the-storms, info.

Keep it safe out there.
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Re: Entering cloud - is Stormscope adequate?

Unread post by Airwayfreak » Tue Apr 19, 2016 7:16 am

Beware embedded CB's even with a Stormscope
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Re: Entering cloud - is Stormscope adequate?

Unread post by Brand » Tue Apr 19, 2016 8:36 am

Airwayfreak wrote:Beware embedded CB's even with a Stormscope
Short and powerful statement.... I have a feeling there is a lot of meaning behind it.
Attitude determines Altitude - in Flying and in Life........

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Re: Entering cloud - is Stormscope adequate?

Unread post by apollo11 » Tue Apr 19, 2016 9:25 am

When Chalkie warns and explains I listen, like Jim Davis and Wildcat , he has pretty much seen a lot and survived
Straighten up and fly right!
Perry

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