Used Storm Gear

Datalink may be creating a glut of used sferics devices but shop carefully. Strike Finder and WX-950 are top picks.

by Larry Anglisano

Is there a great sea change afoot in the world of airborne storm detection? The datalink weather craze is taking off more quickly than we expected and it looks like a phenom with legs.

As a result, were seeing owners ditching their Stormscopes and Strike Finders, suggesting two things: the sferics market may be in decline and bottom feeders will find some terrific bargains on this equipment. But why go with an old Stormscope if datalink is the better product? Easy. Datalink hasnt proven itself yet and it still may be more expensive than a used sferics box.

Plus, maybe you don’t need multi-color airborne radar data or you don’t want to pay the ongoing fees. A decent used Stormscope could be just the ticket. But watch it. Some of the used equipment coming onto the market is no bargain at all and, in this article, we’ll sort through the good and the bad.

Its the FAA, Stupid
The used equipment market has changed drastically from a regulatory view. Gone are the happy-go-lucky days where you could buy a piece of used gear gathering dust in your neighbors hangar and carry it to the shop for installation. Repair stations are in the process of complying with new FAA Part 145 regulations. Detailed supporting paperwork, quality control issues and accountability top the list of specifics contained in this regulation.

FAA FSDOs are making it clear that its not legal to install used equipment-or any equipment for that matter-without appropriate return to service paperwork. This paperwork shows that the installed equipment is functional per original manufacturing specs and is in airworthy condition. For this reason, we caution against buying used gear from fellow owners without a determined consult from an established avionics shop with repair station status.

The shop should advise you of the expected cost to make used gear legally installable and, ultimately, airworthy. Under Part 145, each shop will have a capabilities list that tells which equipment theyre authorized to work on and legally return to service. From a repair standpoint, sferics equipment often falls under a manufacturer-repair-only category and there’s little field service to be done, other than functional tests.

In most cases, plan on sending used sferics gear to the factory for repair, calibration and final blessing before installation. Since factory repair-don’t forget freight charges-will often yield a flat-rate quote, you’ll want to take a hard look at the costs that this will add to your overall purchase. (See the chart for some common flat-rate repair costs on used lightning detection gear.)

As with any used avionic gear, installation hardware including cabling, mounting hardware, connectors and even pilots guides are part of the system. Many shops will refuse to install used equipment without new install kits. If the shop removing the old gear wasnt kind to the cables, new harnesses may be necessary.

Is It Worth It?
So once youve convinced your shop to install a used sferics system, understand this: This installation is not nearly as straightforward as slapping in a navcomm or VFR GPS. Any good shop will recognize that storm gear is susceptible to stray electrical discharge. After all, this passive equipment detects electrical discharges from convective clouds and it wont know the difference between the energy from a cloud or that from your autopilot servo motors if the antenna isn’t placed correctly. Relocation of strobe power supplies and existing antennas, for example, all add to the cost of a storm detection installation.

We have to wonder how long the older systems, including the Series I line of WX-8, WX-10 series and WX-11 series will be supported, although L-3 tells us that parts are still available for the WX-8 and WX-10 systems. And unless a shop is hungry for work, we suspect most will balk at installing this equipment because they simply don’t want to be married to an installation of equipment this old.

Heres a look at a potential case: Say you find a WX-11 system that was removed from an old Bonanza. Its owner will take $1500 for the entire system. It has no certification tags so it needs to go back to the factory for evaluation/certification and alignment. L-3 charges a flat rate of $739 to work the display, $758 to work the processor and if the antenna cant be certified because it has cracks in the housing or is oil soaked, you’ll need to replace it at a cost of over $1000.

Now, youre into the WX-11 system for almost $4000, before installation. To get it into the airplane, plan on another $2000, so your ancient dot painter will cost $6000 total.

In our view, this is not a worthwhile proposition, based on the age of the equipment and the expected availability of support. A veteran L-3 Avionics technical representative notes you could buy a later model system, say a WX-1000 for less money. We agree.

Whats Out There
In the late 1980s, BF Goodrich introduced the WX-1000 Series II Stormscope and the technology didnt change much, except for the look of the display, a nifty looking cathode ray tube. The storm tracking software was also reworked and some bells and whistles, such as checklists and nav mapping, were added. The WX-1000+ had slaved heading interface capabilities and also navaid features when tied with on-board Loran-C. (GPS was yet to come back then.)

The WX-1000 series is a multi-piece system that weighs 11 pounds with its remote processor, panel-mounted 200-mile range CRT display and an ADF-style flat antenna. This is proven gear, in our experience, and can be found in many higher-end airplanes. Were not sure how many of these systems are actually being removed, although there are many on the market. Certain varieties can serve double duty for displaying Goodrich Skywatch active traffic alerting.

We wouldnt frown on installing a used system if the owner understands the weight and balance issues of the heavy remote processor that usually gets mounted back in the tail. If youre going to install a multi-piece system, the WX-1000 is more practical from an installation standpoint than older Series 1 gear. This system is perhaps the most costly to maintain, however, as replacement of the displays CRT will cost we’ll over $1100 alone.

An easier installation is the Goodrich WX-900 Stormscope. This is a no frills device with a green LCD display that can be tough to view in sunlight if the position isn’t optimal. It has only a 100 nautical-mile range and cant be slaved with a heading source. If youre looking for bare bones storm avoidance for your Cherokee or Skyhawk, this could be the right choice if the dollars are right.

The direct competitor to the WX-900 is the Insight Strike Finder. This was a popular piece of equipment in the mid-1990s with its bold design of broad-band digital sampling. Its claim to fame was-and is-superior noise rejection, thanks to its high band width processing compared to other products. The Strike Finder took a ton of sales away from the WX-900 because it had a brighter gas plasma display and 200 nautical-mile range. In current-production Strike Finders, the display has been improved with an ultra bright LED display. (This can be retrofitted to earlier units.)

We suggest that any used Strike Finder be sent back to Insight for evaluation and upgrade to the latest mod status. Insights $300 fee is quite reasonable, in our estimation. Earlier systems utilized an antenna design that prohibited any repair, so if there were problems in the antenna, the only option was replacement. A newer style sensor allows repair of its internal electronics so this is obviously more desirable, but at $2100, it might not be cost effective for a used system.

The Strike Finder can be slaved with an appropriate heading source and some later units can be found with an integral electronic heading stabilization module on the back of Strike Finder itself, eliminating the need for an external bootstrap source. The Strike Finder system consists of only two compact pieces, a sensor (antenna) and the display. If you need 200-mile range, a bright display and heading slave, a used Strike Finder is a reasonable choice. Just make sure it gets a once over from the factory, which is inconveniently located in Canada, although support is good and friendly, too.

Perhaps the best value and our top choice for a used sferics installation is the Goodrich WX-950 Stormscope. This current production unit filled the void between the high-end, high-weight WX-1000 series and the low-end WX-900. It uses a CRT display and, like the Strike Finder, its composed of two pieces, an antenna and display.

It has 200-mile range, two views (120- and 360-degree presentation), cell mode to see developing clusters and strike mode for a less filtered view. It also has a rate counter for measuring intensity and can be slaved for heading stabilization or used as a standalone. The WX-950 is still in production and we expect it to live on, as it has a favorable service record to date.

The only reason its sales have fallen is because of the WX-500 remote system, which is virtually identical in performance and features but doesnt have a display, continues to be a strong seller for those owners moving up to MFDs. We wouldnt expect to see too many WX-500s on the used market and even if there were, the price might be too high to make sense as a used buy.

We believe that storm gear will still serve a useful purpose for quite some time to come but we acknowledge that the switch to datalink technology is already making inroads against sferics. We arent implying that owners who currently have older Stormscopes arent adequately served.

If you have an older 3M WX-10A, for example, it probably gets the job done, so why yank it? But given the regulatory hassle and installation expense, we would advise against buying one used.

Also With This Article
Click here to view “Checklist.”
Click here to view “Why Bother With Sferics At All?”
Click here to view “Used Sferics Flat-Rate Refurb.”

-Larry Anglisano is Aviation Consumers avionics editor.