Aviation In Canada

Saturday, August 06, 2005

Canadian ATC Weather Radar

A number of pilots are flying in Canada without the benefit of weather radar on board. Many of these know that ATC has some capability of weather radar. Even those who have their own on board often ask ATC what they show. The usual response includes some kind of statement denouncing our capabilities.

In the past, the analog radar ATC used had a number of dials and controls that could be used to filter out weather to increase the ability to see aircraft. These same "filters" could also be adjusted to spot weather phenomena better. With Transport Canada's RAMP initiative (Radar Modernization Project), new radars were built and installed, and these units used a different wavelength on the primary radar (the radar which relies on reflected energy to detect aircraft). The changes in the wavelength put together with computer processing of target information changed many things in the controller's presentation, and the weather detection suffered in the process. ATC often sees "blobs" of weather that either isn't there or is not significant from a pilot's point of view, and often will be told about weather when we don't see anything there. Mind you, if the radar covering a particular area doesn't have primary capability, no weather will be shown at all, regardless. And ATC's weather capability is limited to 100 NM from a capable radar anyway, so our weather radar capability is quite limited.

Thankfully, a relatively new addition to ATC's weather displaying ability has made its way across the country in varying stages. I believe Moncton was the last to come online with it (I amy be wrong about that fact, but in any case it was largely due to the implementation of CAATS, our new system, which delayed Moncton's displays). Canadian IFR ATC units now have the ability to display lightning strikes detected by the National Lightning Detection Network. Once each minute the data is updated and displayed, with the source of the lightning detection reported as being accurate to within 500m, or 1/2km, or in nautical terms, about 1/4 NM. This doesn't predict where lightning will strike, but it shows where it has struck, and give ATC an idea of the direction of movement of a system and how much lightning is generated by it, also possibly giving some insight as to whether the system is strengthening or weakening over time.

I know some pilots are already aware of other units' lightning information availability, since a week before Moncton finally received the same information, I had two pilots ask me about lightning data while a heavy set of cells romped through our FIR. Anyway, hopefully this will be able to help ATC plan around thundercells and help pilots steer clear of them. As we've been talking lately, CBs are no place for an airplane to be.