Storm scope anomalies

[Mark89114]

Before I take my 2000 ovation to the avionics shop I thought I would do some basic troubleshooting.  I have reached my limits of what I can do easily.

i have strikes on the nose and tail at 200 mile setting, I have also started getting random marks almost always at the same position.  I have turned off all lighting, checking easy stuff and thought I had it nailed down to extrernL lighting but strikes came back.m also turns off iPad, phones, etc. Just yesterday coming around what I would think would generate enough sferics to show, got almost nothing.  I mentioned this to don maxwell and he mentioned oil between sensor and fuselage.  Autoplit was on for All flights,  Could noisy servos cause?

i think what I will do is go out and turn avionics on without engine and see what happens.

any troublseshooting advice would be appreciated.

[carusoam]

Which model / device you have might be helpful?

Best regards,

-a-

[Jerry 5TJ]

I see intermittent "issues" with my Stormscope wx500 in 2000 Ovation as well:

---clusters of cell mode indications at 12 o'clock (once formed they track heading but reappear at 12 o'clock position) on start up and very infrequently in flight.

--message on 750 "stormscope data link fail" that persists a minute and then stormscope operation resumes. 

--Generally all works well and cells/strikes agree with XM Lightning depictions in azimuth and range out to 150 miles or so.  

--At annual this week I confirmed the antenna to belly skin seal is intact.  Antenna was quite dirty with oily coating outside but clean inside panel & well grounded.  Cleaning the antenna cover can't hurt.  

None of this solves your problem, I know.  Like you I'm still trying to separate symptoms and potential fixes.  

The very nature of Stormscope makes it potentially noisy & susceptible to static, motor noises & our Ovations are full of potential sources.

At annual we just found an arcing connector in the L wing tip strobe that could have made some strike-like noise:

 

Good hunting!

 

[takair]

Mark.  If this is a new symptom then the stormscope is telling you something.  You are on the right track isolating.  Try turning of autopilot as well. Beyond that it can be in the engine compartment.  Turn off alternator too.  Beyond that an inspection under the cowl can be in order.  Ignition wires, grounds, etc.. I have also seen loose inspection panels cause this.  Gear doors would be on my list as well, but toward the bottom. (Does gear up and down make a difference?)

[ArtVandelay]

I see this too on a old WX10, I had a TS off my wing, maybe 15 miles, saw a lightning strike to ground but no dots except the normal few front and aft. After I landed, at night, I saw a bunch at 10 o'clock position. Have you tried it to see if it will detect actual lighting strikes?

[Marauder]

Here is a StormScope anomaly that you might find amusing. Since my WX-500 is synced with the heading, I could do a complete circle of "storms" around me. Interestingly my WX-500 only showed these anomalies at the 200 mile range as well.

In my case, the Whelen beacon strobe was causing it. Whelen sells a new cover for the strobe that shields the interference.

Sent from my iPad using Tapatalk

[Mark89114]

I knew someone would ask me what model it is....embarrassed to say I don't know.  I am currently without car so can't get to Airport till Wednesday.  I will try to nail it down issues with more accuracy, engine on/off(on ground obviously.....) alternator on/off, AP on/off with all of above conditions.  I am not sure it works regardless, been fantastic weather, but yesterday I should have seen something.  I also press test feature and it doesn't really do anything.  Will report back this week, have a safe 4th everybody.  I also had some type of lightning detection when flying a hawker 800, it never impressed me either.

[carqwik]

My WX-950 is very useful...tells you where you can't go for sure!  Only one issue is that the heading stabilization won't work until it gets some cool air at altitude...

[Jerry 5TJ]

19 hours ago, Marauder said:

.... Interestingly my WX-500 only showed these anomalies at the 200 mile range as well...

Stormscope interprets lightning strike signal amplitude and maps it as a range relative to an average strike.   Exceptionally strong storms are displayed as closer than they are.  (A good error bias)

Weaker and stronger strikes in the same Cb cell show up in the Stormscope's "strike" mode as a series of radial points at same azimuth but various distances.  

Weak interference sources thus appear at the max range.  When you reduce the range setting you are decreasing reception sensitivity.  

[takair]

16 hours ago, Mark89114 said:

I knew someone would ask me what model it is....embarrassed to say I don't know.  I am currently without car so can't get to Airport till Wednesday.  I will try to nail it down issues with more accuracy, engine on/off(on ground obviously.....) alternator on/off, AP on/off with all of above conditions.  I am not sure it works regardless, been fantastic weather, but yesterday I should have seen something.  I also press test feature and it doesn't really do anything.  Will report back this week, have a safe 4th everybody.  I also had some type of lightning detection when flying a hawker 800, it never impressed me either.

Many avionics shops have a test set to simulate strikes- range and bearing.  A "poor mans" test set can be a better you powered or electric drill held near the stormscope antenna.  Should light it up pretty good. A properly installed detector should do a firmly reasonable job of keeping you out of storms.  It is still more of a strategic device, but unlike datalink weather it is real time.  It is also a good predictive device. It will (should) show a building T storm before your radar can detect it, it is thus complimentary to the radar in the Hawker.  They are not perfect in range and bearing, but are better than nothing and certainly not obsolete, even with datalink.  Goodrich used to put out a really good pilots guide on interpreting the stormscope.  Worth the read if using one and generally applies to all spherics devices.  

[Bob_Belville]

1 hour ago, Jerry 5TJ said:

Stormscope interprets lightning strike signal amplitude and maps it as a range relative to an average strike.   Exceptionally strong storms are displayed as closer than they are.  (A good error bias)

Weaker and stronger strikes in the same Cb cell show up in the Stormscope's "strike" mode as a series of radial points at same azimuth but various distances.  

Weak interference sources thus appear at the max range.  When you reduce the range setting you are decreasing reception sensitivity.  

Good description.

You can safely ignore a few random strikes. And when you are in range of real cells you will find it useful to refresh pretty frequently. Cells build and dissipate. You don't care much about what was happening 10-15 minutes ago. If a cell is building it will quickly reappear after a refresh and as Jerry points out it will plot repeated strikes along the radial toward your position. Remember to hit refresh!

[carqwik]

"Cell" mode eliminates some of the radial spread issues....it gives a good clustering of "x's" where the cell is located. 

[Bob_Belville]

5 minutes ago, carqwik said:

"Cell" mode eliminates some of the radial spread issues....it gives a good clustering of "x's" where the cell is located. 

My 900 does not have that feature... I guess the 950 is newer?

[Marauder]

5 minutes ago, carqwik said: "Cell" mode eliminates some of the radial spread issues....it gives a good clustering of "x's" where the cell is located. 

My 900 does not have that feature... I guess the 950 is newer?

I just looked at both POH for the 900 and 950. The 900 doesn't have the cell capability.

The cell versus strike feature is nice. When I had the WX-8 it was a challenge to discern the exact range due to radial spread. I just learned not to trust the distance indication and deviate away.

Sent from my iPad using Tapatalk

[Bob_Belville]

10 minutes ago, Marauder said:

I just looked at both POH for the 900 and 950. The 900 doesn't have the cell capability.

The cell versus strike feature is nice. When I had the WX-8 it was a challenge to discern the exact range due to radial spread. I just learned not to trust the distance indication and deviate away.

Sent from my iPad using Tapatalk

Interesting. That software solution (cell mode) does what a pilot learns to do. Refreshing display every few minutes minimizes the radial spread effect. Plus, if you don't like what it looks like just erase it.

[Marauder]

10 minutes ago, Marauder said: I just looked at both POH for the 900 and 950. The 900 doesn't have the cell capability.

The cell versus strike feature is nice. When I had the WX-8 it was a challenge to discern the exact range due to radial spread. I just learned not to trust the distance indication and deviate away.

Sent from my iPad using Tapatalk

Interesting. That software solution (cell mode) does what a pilot learns to do. Refreshing display every few minutes minimizes the radial spread effect. Plus, if you don't like what it looks like just erase it.

Yep, just like when you close your eyes before entering that big dark cloud off of your nose.

The cell feature is pretty slick but my favorite feature of these new StormScopes is the heading synchronization.

Sent from my iPad using Tapatalk

[M20F]

Loose alternator wire caused a consistent pattern on mine.  Fixed the wire and the stormscope went back to working. 

[Jerry 5TJ]

9 hours ago, Bob_Belville said:

Interesting. That software solution (cell mode) does what a pilot learns to do. Refreshing display every few minutes minimizes the radial spread effect. 

The user manual for the WX500 stresses the use of refresh to determine if the storm is building or dissipating.  Stormscope interpretation is a learned skill.  There are videos to help.  Flying near, but not too near, Cb and watching the storm out the window and the display is very helpful to learning to "see" with the Stormscope.  

 

[Bob_Belville]

7 hours ago, Jerry 5TJ said:

The user manual for the WX500 stresses the use of refresh to determine if the storm is building or dissipating.  Stormscope interpretation is a learned skill.  There are videos to help.  Flying near, but not too near, Cb and watching the storm out the window and the display is very helpful to learning to "see" with the Stormscope.  

 

 

Thanks Jerry. That confirms what I've learned after flying with Stormscopes for many years. I trust them completely to keep me out of the rough stuff.  

[jetdriven]

When you shoot the gap it sometimes looks like this. It was cleared about 45 seconds before. 

[Bob_Belville]

6 minutes ago, jetdriven said:

When you shoot the gap it sometimes looks like this. It was cleared about 45 seconds before. 

Yup. Clear and zoom to 50 or even 25 nm!