Menu Sign In Contact FAQ
Banner
Welcome to our forums

WX500 Stormscope Error 18

My KI229 RMI was removed (redundant due to the SN3500 EHSI) and replaced with the 3" EDM700.

Unfortunately the WX500 stormscope (displayed on the KMD550) now complains with Error 18 which is variously described as a "processor fault" here (page 14 of the PDF), and a notification of a need to recalibrate here. The installation manual puts it more strongly (page 52 of the PDF).

Funnily enough, a look at the WX500 error log shows that Error 18 has been happening intermittently for a while - years

Assuming that error log really shows hours, this means it has been going on intermittently for a very long time. 1500hrs is about right for a total running time of this WX500.

What I can't be sure of is whether the WX500 is still working, We don't have any nearby lightning strikes in the UK at the moment. But I think that whenever Error 18 is showing, it isn't doing anything.

Two things happened recently. The TAS605 traffic system went in in December 2012 (and the TAS605 box is right next to the WX500), and I did have huge problems with the installer having bodged that job. And the KI229 RMI was removed 2 days ago.

Administrator
Shoreham EGKA, United Kingdom

We don't have any nearby lightning strikes in the UK at the moment.

You should've been with me yesterday - right through embeded Cb on decent from RUDIK to PIS on arrival to LDZA. My passanger was pretty cool with rain shower until she spotted first lightning and noticed auto-pilot turned itself off due to heavy turbulence and I was manually flying the aircraft.

Before departing Dubrovnik I analyzed situation with guy at meteo office and conclusion was that there was possibility of isolated TCu development in RUDIK area which wasn't supposed to develop to Cb. I turned stormscope to realize that it didn't work showing some error (antenna fault - has to be replaced). Arriving to RUDIK point the situation looked exactly as expected with some TCu in front of me in the area of PIS NDB. However, in next 5 min a lot of Cu development emerged with some embedded TCu and I descended into solid Cu layer heading more-less in direction of one TCu (exactly above PIS). Of course it turned out that this TCu in next 5 mins developed to Cb :( exactly when I arrived. At that moment 4 commercial big jets asked radar to allow them changing course for avoiding the weather approaching PIS - it was too late for me - I was there. It was non pleasent but survivable scenario - unfortunatelly I wasn't able to make some pics or clip and my passanger wasn't in mood to help on this.

BTW ADF was so erratic showing 30 degrees incorrect track comparing to actual NDB position comparing to GPS.

LDZA LDVA, Croatia

Update:

It turned out to be yet another intermittent fault, which disappeared next time I turned things on.

A stormscope doesn't do a huge amount but it very reassuring for long haul passengers who quickly learn which button on the MFD to press

Dubrovnik gets impressive thunderstorms. I flew in there a few years ago (VFR, for some reason) and the runway was disappearing in front of my eyes, getting gradually obscured by a dense downpour. I had asked if I could fly the ILS earlier which was approved, but ATC now warned that there is a CB in the missed approach area. Well... one could see it well enough. I just did a 180 and flew around in between the islands at ~ 1000ft until the storm cleared. Some Brit airbuses actually landed in those conditions.

Administrator
Shoreham EGKA, United Kingdom

The fault log does show hours and the recabliration you referenced is for a SKY497 Skywatch traffic system. Your WX-500 appears to be working just like it should... the probable cause for error code 18 is your antenna is in a noisy location, a faulty antenna or a wiring problem. www.stormscopes.com

Interesting. Many thanks.

Is the antenna active, or passive?

It is easy enough to rewire, as the WX500 is in the rear of the aircraft. Laying some RG400 is no problem.

Administrator
Shoreham EGKA, United Kingdom

It came back today.

The KMD550 is not receiving heading data. During flight the map is track-up, as it should be, but that comes from GPS data. If I go into the config page (password 3333) I can see the heading is INVALID. There is a heading flag which can be set HIGH or LOW and whatever I change that to, its actual value changes to the opposite state!

Obviously this needs to be looked at properly...

There is a bit of a history to the heading to the KMD550. In the early life of the TB20 it did not work, later I got it fixed, and it looks like it has now gone.

Today, the map display was showing everything correctly, except (a) no TCAS data on the map (which I know is a symptom of a lack of heading data to the MFD) and (b) the little aircraft icon, which normally points according to the actual heading (so you can see the wind offset from the track) would sometimes flip to point somewhere totally different.

This trouble started with the removal of the KI229 and I suspect the KI229 had a handy pullup / pulldown resistor in it which the system relied on without anybody knowing about it. It could be just the heading flag that is intermittent.

Administrator
Shoreham EGKA, United Kingdom

The antenna is passive. Most of the time error 18 is due to the antenna cable picking up aircraft noise.

On another ground test today the system has behaved just fine, with everything except the engine running. Noise test (admittedly run for only seconds) shows nothing.

But I think there is something wrong with the heading information going to the MFD and the WX500 - see this (77MB video).

Administrator
Shoreham EGKA, United Kingdom

you can test a stormscope by holding a regular battery powered drill about 4 feet from the antenna.

EHLE, Netherlands

I don't doubt the WX500 itself is working, but without a heading going to it, it won't display anything on the MFD, except in the stormscope screen. It won't overlay onto the map.

And same with the TCAS.

Administrator
Shoreham EGKA, United Kingdom
12 Posts
Sign in to add your message

Back to Top