Stormscope actually useful?

Hopefully this post will bring some differing opinions, because I want to believe that a Stormscope is actually useful.

But, in both planes that I have ever flown with a stormscope, the stormscopes are not accurate in depicting the distance to the strikes. Direction to strikes seem to be fairly accurate, but distance is very deceiving. To me, distance is as important as direction. Both planes I have experience in both showed strikes a lot closer than they really were.

If in fact these experiences are consistent with others, how do you guys actually use the stormscope to actually make this instrument useful?

Paul #250


I give lectures and training workshops on the stormscope. I have a power point you might find useful in learning how to use and interpret the wx-500. The power point is to big to e-mail so I would have to send it on a cd. Give me a call and I’ll help you out.

Christian V. Cherniak

This is my first plane with a stormscope, and I find the display of the strikes to be fairly accurate. I’ve herd about radial spread, which as I understand it makes very powerful or numerous strikes appear to be closer than they really are.

I have never measured the distance to the strikes, (I just haven’t found out how to), but my display appears to be very accurate. In circumstances when a CB was very visible, the azimuth was clearly within a few degrees and the distance was arguably correct.

I tend to use my device for more strategic guidance as opposed to trying to thread my way between numerous, closely spaced storms, so if the distance is off a bit, it is not a major factor (for me).

the biggest ‘error’ I’ve found is that it has occasionally shown a single hit that I am confident is not there. I do not know if it is from static buildups which are clearly not result of lightning or from some other source of electrical interference. I a fairly confident that it is not from within the aircraft as there have been no consistent false replies.

Overall, I am very happy. I have it set up so that I display the strikes on both the ARNAV and the Sandel. I use one for longer range (150 -200 NMs) viewing and the other for short range (25-100) viewing. This also alerts me if there are any problems in the system.


I’ve had the fortune to not encounter too many thunderstorms, so most of what I’ve seen on the Stormscope has been isolated CBs, but on one occasion I had a solid line of storms depicted about 100 miles east of my course, and the position showing on the Arnav display corresponded well with the reported location of the storms.

I find the Stormscope very useful even if the range and azimuth are not exact. The idea is to avoid areas of convective weather, not individual cells per se. Another way to look at it is to say that the Stormscope provides strategic rather than tactical avoidance information. If a storm shows closer than it is, you will deviate to stay away and that will take you even farther away than you need to be. Far away is good. Too near is bad.
What’s important is that you don’t try to avoid individual cells. That may be possible with radar but it’s not a good idea with the Strormscope. Here in the Midwest some sort of thunderstorm avoidance is necessary if you want to fly in the warmer months. My last aircraft had radar, my Cirrus has the Stormscope. I personally find the Stormscope more helpful in staying away from areas of activity.
Jerry Seckler


Would you care to “illuminate” the rest of us with an executive summary of your conclusions?

I’m a lowly position holder (#544) and I’m hoping to get my SR20 before I’m too old to fly, but I have a Grumman Tiger with a Stormscope. The little “manual” that comes with it explains radial spread. It looks like a pie shaped wedge with the sharp end pointing toward your present position. The cell is some distance out the pie slice, approximately where it gets fattest.

This actually provides pretty good avoidance data, as the returns taper away from the heading you definitely don’t want to take.