stormscope recommendation

[Oscar Avalle]

My NEXRAD and my wx900 worked well together while I was flying int he northeast. However now I feel that my wx900 is not enough and I am installing a wx500 with longer range and better software.

[Piloto]

The NEXRAD lag that some experience is not that much due to the XM broadcast but to the XM receiver that misses WX updates due to antenna shadowing effect when located inside the cockpit. The same happens with ADS-B WX. With an external XM antenna the oldest WX I have seen is 6 minutes. Keep in mind that NEXRAD is used by ATC to guide pilots around weather and is also used for tornado warnings, so it can not have much of a lag. Satellite image is useful in prediciting areas of high weather activity before lighning or precipitation occurs. Satellite image is very useful in predicting and assessing hurricane formation over the ocean. When NY Oceanic Radio issue SIGMETS for the North Atlantic they are all based on satellite images.

José

 

[AndyFromCB]

Quote: Piloto

The NEXRAD lag that some experience is not that much due to the XM broadcast but to the XM receiver that misses WX updates due to antenna shadowing effect when located inside the cockpit. The same happens with ADS-B WX. With an external XM antenna the oldest WX I have seen is 6 minutes. Keep in mind that NEXRAD is used by ATC to guide pilots around weather and is also used for tornado warnings, so it can not have much of a lag. Satellite image is useful in prediciting areas of high weather activity before lighning or precipitation occurs. Satellite image is very useful in predicting and assessing hurricane formation over the ocean. When NY Oceanic Radio issue SIGMETS for the North Atlantic they are all based on satellite images.

José

 

[AndyFromCB]

Can we all at least agree that T-Storms when viewed from a distance are very pretty ;-) Image below is from 18K, the storm to the side is still just building and it is at least as high over me as I am over the ground.

[Piloto]

astelmaszek

As the NTSB indicates the NEXRAD delays are rare. Since you are experienced with the Stormscope how do you assess if the activity it indicates is closer than your destination or farther than your destination. Unlike the XM\WX lighning detection accuracy of 0.2nm the Stormscope range accuracy is 50% of the scale. So you could be flying into real time lighning that is closer than indicated.

José

 

[johnggreen]

First, Astelmaszek, please get a shorter handle !

Second, I have navigated my way around (and sometimes inadvertantly through) my share of bad weather, but I'm not going to add my two cents to the debate because Jetdriven and Astel------- have published the truth.

This is a big issue right now with publications and studies from all sides including the NTSB.  There really is no debate among informed pilots or authorities.

Trying to pretend that the 20 minute old info from XM or WSI will allow you to navigate turbulent weather when a TS can form in less than ten minutes is just insane, so go back and read JD's and A---------- post.

And A--------- stay out of the red.  I don't give a damn what the Stormscope says.

Jgreen

[AndyFromCB]

Quote: Piloto

astelmaszek

As the NTSB indicates the NEXRAD delays are rare. Since you are experienced with the Stormscope how do you assess if the activity it indicates is closer than your destination or farther than your destination. Unlike the XM\WX lighning detection accuracy of 0.2nm the Stormscope range accuracy is 50% of the scale. So you could be flying into real time lighning that is closer than indicated.

José

 

[bd32322]

thanks for the great viewpoints - especially the points about:

1) stormscope is directionally accurate - it gives an accurate bearing to the lightning

2) stormscope is range inaccurate

3) NEXRAD is position accurate but has old data.

4) ASR radar is both position and time inaccurate

5) Need to know the big weather picture.

We should start a separate thread or forum section for weekly weather problems on this. Every week someone posts a 600 nm theoretical trip to be taken the next day - and people can chime in with what they think the weather scenario will be at flight time and what will be their go/no-go decision for IFR/VFR. I and probably others could benefit from seeing first hand the decision making process and knowledge that goes into flight planning with weather !

[Hank]

Great discussion and details on the Stormscope.

I'm SHOCKED that anyone is still flying with XM weather, thinking that it is current as of the time shown. That time is just when it was released, and does not take into account the time required to gather, digest and create the composite picture, thus the 6-10 minute average delay that is longer during active weather.

Coming home through NC yesterday in the early afternoon, Center advised me of "heavy to extreme precip" ahead of me, just after I asked to deviate left around the buildup. It was nice and tall and not too dark, with a nicely developed anvil on top. Stormscope was clear. I deviated left around it and a few other tall CB behind it, and reported back when I could see from the side "no visible precip beneath the buildup." Nary a bump to be felt except when clipping tops.

See http://flightaware.com/live/flight/N444DJ and the course shift is very visible. I think the 430 showed about 15 left of course at the max as I paralleled along. I'm not sure what weather flightaware presents; the anvil was spreading off to the east, so I took the longer way around and went left, up to almost 40º at one point. I took a picture with it in the distance, but don't have my camera with me right now.

No XM, so I can't comment on what it showed other than Center's "heavy to extreme precipitation" comment in response to my deviation request. So I asked again and deviation to the left was approved as I was turning the yoke.

Bases were mostly 5-6000', and tops rose from below me to 9-10,000 the further NW I traveled; this one was much, much taller. I probably could have climbed to 10K for better distance visibility, but with the temps aloft she wasn't climbing too well reaching 8000 and I didn't have much trouble spotting buildups. Think I logged 0.3 actual, usually in bursts of a few seconds to 3 minutes.

[Hank]

Recap:

Stormscope

accurate direction, real-time; distance not so good.

XM Weather

long range, good for tracking motion; old data.

[WardHolbrook]

I use the Stormscope to decide what to avoid and the wx radar preferably and NEXRAD, et.al. to avoid them. As for the visual part of it, I've found that how clouds look on the outside is one of the least accurate ways to determine how they are on the inside - I've seen some relatively benign looking clouds that packed a mean wallop and I've flown through some mean looking stuff that was benign. That's where the the stormscope comes in, to help you differentiate between the good stuff and the bad stuff. In 25 years and 10,000 hours of flying behind them, they've never once steered me wrong. As for discounting the outside appearance of a cloud, I'll just say that if you were flying at night, how would you ever know how the cloud looked anyway? Screwing around with buildups isn't something you want to be doing without the proper equipment and the skill and experience to use it correctly. As long as the spherics detector isn't showing any discharges, I'm usually up for continuing. A little rain never hurt anybody, green and yellow returns together with a clear Stormscope display will only result in an airplane "pressure wash". However, I do draw the line at red or greater returns.

My technique doesn't vary with the type of equipment I’m flying. As I have said previously, personally I use the Stormscope to determine if the area is safe to transit (NO Discharges showing on the display) and then some sort of weather radar to circumnavigate the area. The reason being is that while it's good at detecting areas of convective turbulence, a Stormscope lacks the close-in resolution to be able to pick your way safely through it. When it comes to tackling weather like this, whether you’re IFR in a jet or VFR in a light single you DO have to be able to see it - however, you can see it using on board avionics just as well as you can see it with your own two eyes. That is where the Stormscope / Radar combination comes into play.

You need to remember this about weather radar (airborne and ground based) - essentially all it can show you is dirt and water. If all you're seeing is dirt then you've got the tilt set too low. As for water, the assumption is made that where there's atmospheric water (rain) that's being displayed it is accompanied by turbulence. In other words, if you've got precipitation you've got turbulence and that's not always true. The spherics detectors (Stormscopes) detect electrical discharges in the atmosphere generated by turbulence - a much more reliable way to detect it. Some of the ground based dopler radars that we can receive in the cockpit are very capable at detecting turbulence, the only problem there is that by the time you actually get the updated information into the cockpit it can become "stale". Refresh rates are problematic.

Bottom line for me is this...

1. Any time you screw around with convective turbulence you've got to be visual. However, you can see it with your avionics just as well as you can see it with your own two eyes. The operative words are SEE and AVOID.

2. Red/magenta returns whether or not associated with turbulence (as indicated by the stormscope) are always too much. Anything less, when accompanied with a "clear" Stormscope display is a just free airplane power wash. Precipitation on the radar and no "dots" on the stormscope = smooth, but wet ride. No precipitation on the radar and dots on the stormscope = bumps, you don't want to be there. Precipitation on the radar and dots on the stormscope = big bumps and you really don't want to be there.

3. I'll take a stormscope and on board wx radar as my first choice any day. If on board wx radar isn't an option then XM radar can be a workable substitute.

4. XM weather by itself is not a substitute for the stormscope / radar combination, but it's better than nothing.

 

 

[PTK]

Quote: WardHolbrook

 

I use the Stormscope to decide what to avoid and the wx radar preferably and NEXRAD, et.al. to avoid them. As for the visual part of it, I've found that how clouds look on the outside is one of the least accurate ways to determine how they are on the inside - I've seen some relatively benign looking clouds that packed a mean wallop and I've flown through some mean looking stuff that was benign. That's where the the stormscope comes in, to help you differentiate between the good stuff and the bad stuff. In 25 years and 10,000 hours of flying behind them, they've never once steered me wrong. As for discounting the outside appearance of a cloud, I'll just say that if you were flying at night, how would you ever know how the cloud looked anyway? Screwing around with buildups isn't something you want to be doing without the proper equipment and the skill and experience to use it correctly. As long as the spherics detector isn't showing any discharges, I'm usually up for continuing. A little rain never hurt anybody, green and yellow returns together with a clear Stormscope display will only result in an airplane "pressure wash". However, I do draw the line at red or greater returns.

My technique doesn't vary with the type of equipment I’m flying. As I have said previously, personally I use the Stormscope to determine if the area is safe to transit (NO Discharges showing on the display) and then some sort of weather radar to circumnavigate the area. The reason being is that while it's good at detecting areas of convective turbulence, a Stormscope lacks the close-in resolution to be able to pick your way safely through it. When it comes to tackling weather like this, whether you’re IFR in a jet or VFR in a light single you DO have to be able to see it - however, you can see it using on board avionics just as well as you can see it with your own two eyes. That is where the Stormscope / Radar combination comes into play.

You need to remember this about weather radar (airborne and ground based) - essentially all it can show you is dirt and water. If all you're seeing is dirt then you've got the tilt set too low. As for water, the assumption is made that where there's atmospheric water (rain) that's being displayed it is accompanied by turbulence. In other words, if you've got precipitation you've got turbulence and that's not always true. The spherics detectors (Stormscopes) detect electrical discharges in the atmosphere generated by turbulence - a much more reliable way to detect it. Some of the ground based dopler radars that we can receive in the cockpit are very capable at detecting turbulence, the only problem there is that by the time you actually get the updated information into the cockpit it can become "stale". Refresh rates are problematic.

Bottom line for me is this...

1. Any time you screw around with convective turbulence you've got to be visual. However, you can see it with your avionics just as well as you can see it with your own two eyes. The operative words are SEE and AVOID.

2. Red/magenta returns whether or not associated with turbulence (as indicated by the stormscope) are always too much. Anything less, when accompanied with a "clear" Stormscope display is a just free airplane power wash. Precipitation on the radar and no "dots" on the stormscope = smooth, but wet ride. No precipitation on the radar and dots on the stormscope = bumps, you don't want to be there. Precipitation on the radar and dots on the stormscope = big bumps and you really don't want to be there.

3. I'll take a stormscope and on board wx radar as my first choice any day. If on board wx radar isn't an option then XM radar can be a workable substitute.

4. XM weather by itself is not a substitute for the stormscope / radar combination, but it's better than nothing.

 

 

 

[Piloto]

Quote: Hank

Recap:

Stormscope

accurate direction, real-time; distance not so good.

XM Weather

long range, good for tracking motion; old data.

[AndyFromCB]

Quote: Piloto

You are overlooking all the other weather parameters that XM offers suchs as NEXRAD, satellite, winds aloft, metars, forecast, top of clouds, TFRs, icing. and accurate lightning that the Stormscope does not provide. As far as performance due to the poor range accuracy of the Stormscope the range error is worst than any error on the XM data. When approaching an airport, with XM I have a much more accurate idea of the weather location than with the Stormscope dots. If you are maneuvering the Stormscope weather depiction smears unless you clear the dots after stablishing a new heading. With XM\WX the angular and distance depiction is instantaneous. My opinion is that due to Stormscope poor range accuracy and latency is not good at all for maneuvering around weather. What Stormscope is good for is in areas where there is no XM coverage.

José

 

[carusoam]

Why so harsh????

-a-

[M016576]

Some of you guys are brave... Much braver than me.  If its a single engine recip, I don't fly at night and I don't fly IFR unless it's a confirmed low stable mass and only in the terminal area (ie something I climb through or descend into... No cruising around in the clouds for great distances in my mooney).  I use XM weather to ensure my pre flight planning is developing as expected.  If it isn't, And for some reason CB convective activity that wasn't forecast is building, I turn around or divert.  The hardest part about that is making the actual decision... But as they say.. The truth will set you free!  

I guess if you're hard core about flying a light civil into building activity, a stormscope would be prudent... But to me that kind of feels like driving a Jetta into a blizzard and feeling ok about it because you have snow tires.  We each have our own comfort thresholds and risk tolerances, though, make your choices and stay safe!

[Piloto]

Quote: astelmaszek

You are overlooking all the other weather parameters that XM offers suchs as NEXRAD, satellite, winds aloft, metars, forecast, top of clouds, TFRs, icing. and accurate lightning that the Stormscope does not provide. As far as performance due to the poor range accuracy of the Stormscope the range error is worst than any error on the XM data. When approaching an airport, with XM I have a much more accurate idea of the weather location than with the Stormscope dots. If you are maneuvering the Stormscope weather depiction smears unless you clear the dots after stablishing a new heading. With XM\WX the angular and distance depiction is instantaneous. My opinion is that due to Stormscope poor range accuracy and latency is not good at all for maneuvering around weather. What Stormscope is good for is in areas where there is no XM coverage.

José

 

[Piloto]

 

Tired of this thread. My last 3.5 cents:

1.) Both the stormscope systems I've used in the past and continue to use today do not "smear", both are heading stabilized.

The majority of Stormscope in the field are not heading stabilized. So you have to clear the dots. 

2.) You're using the words latency to describe the stormscope, where there isn't any. The second a strike is detected, it's displayed, just like that. There is no latency.

On the Stormscope the range depiction to the dots does not change as you approach the last dots. The dots remain fix on the display until new strikes are received, that is latency

3.) The distance error is not a major issue in cell mode. If I recall correctly we deviate by a heading and stormscope is dead on there.

Unfortunately there is a wide variation in lightning strikes intensity that makes the Stormscope inaccurate for range. Strikes can have over 30dB variation. Lightning detection by the NWS (XM) employs multilateration (differential time of arrival) tecniques for pinpoint position accuracy. 

I can what you mean, the older stormscope systems required a pilot to build a mental map of the developing storm, especially with each heading change to deviate. Neither WX1000 or WX500 require you to do that, the picture stays.

Why bother with mental maps when XM\WX weather depiction is overlayed on the map. I am too old for mental maps.

4.) You're using the word instant describing XM. No, up to 20 minutes old is not instant at all, even 5 minutes old is not instant. Remember, even 1 second old on your display is actually 5 minutes old. 5 minutes can mean 30,000 feet and growing CU.

On the XM\WX when I change heading and distance the weather moves accordingly. On the Stormscope I have to clear the display and wait for new dots. 

5.) Last but most important: a building thunderstorm that has not started to rain but on the other hand has a 6000fpm updraft inside will not show up on your NEXRAD, it will show up on my stormscope.

That's what XM satellite image is for. Before anything shows on NEXRAD or Stormscope it will show on the satellite image. Weather prediction is based mostly on satellite image like hurricane formations over the Atlantic, no Stormscope there. 

As to the other features, I agree, XM is a great tool, I have both in my airplane but while I can fly without XM, I can't and won't fly hard IFR without a stormscope.

6.) Only 10% of all lightning hits the ground and that's all you see on your XM display. 90% is cloud to cloud and it starts long before any ground strikes.

The ones I care are the ones that are going to kill me and those hit the ground hard.

At last, I will repeat myself again, there is no latency stormscope what so ever.

If you don't clear the dots the strike that hit you will do it.

[johnggreen]

Andy,

Astel Maszek, then that's ok and a really "cool" name !  My youngest son, now 26, often thanks me for giving him a memorable "cool" name; Grant Green.

In the interest of brevity though, I'm gonna just call you Andy.

Again, thanks for the posts on this thread.

Jgreen

[gregwatts]

Quote: jetdriven

XMWX shows only cloud-to-ground lightning that is at best, ten minutes old. Thats the second worst weather advice I have ever heard. Next we are going to hear how you can get lightning on your iPhone from the weatherchannel.com. But I only have 3 type ratings and fly all over the world. BWTFDIK?

[PTK]

We can get lightning on the iPhone from the wx channel? 

Is there a lag? Does it come with a pretty meteorologist or are we stuck with Al?!

[jetdriven]

Quote: gregwatts

A type rating only proves that you know the systems of a particular aircraft. You can buy those at Simcom......doesn't mean you know any more than anyone else offering their opinion. Don't be rude!

[johnggreen]

Byron,

Perhaps now, you can appreciate the frustration that has often caused me to "lose it" on this site.

Jgreen

[fantom]

Quote: johnggreen

Byron,

Perhaps now, you can appreciate the frustration that has often caused me to "lose it" on this site.

Jgreen

[WardHolbrook]

I currently fly behind a 24" dish with dopler and an integrated spherics detector (Honeywell LSS). As good as that system is, the best system I ever flew behind was a Lear that had a new vertical profile radar and stormscope combination. I flew that airplane all over the US, including a lot of trips in the mid-west, for nearly 3,000 hours and never once did that combination lead us where we didn't want to be or shouldn't have gone. Like I said earlier, the stormscope does a very good job of allowing you to plan strategically and the on board wx radar allows you to fly tactically. I've flown with XM weather and we currently have Nexrad on our airplanes as well. They are a poor substitute for airborne wx radar, but the kicker there is that without proper training in the use of radar, you're better off not even turning it on. Proper training means attending on of the weather radar courses. There are many ways onboard weather radar can get you killed if you're not proficient and up to speed with basic stuff like range, tilt, gain, attinuation, STC range etc...

If I ever buy a personal twin, it will have a VP radar and a Stormscope. XM weather would be nice for other things (Metars, TAFs, Winds Aloft, etc.) but to use it tactically for thunderstorm avoidence isn't necessarily one of them.