The difference is that you can see the whole picture, not a verbalisation from ATC. Furthermore, your magenta line is painted through the picture hundreds of miles ahead, so you can see where the potential problems lie. Many times I have negotiated different routes or STARs to avoid areas of weather.
Peter wrote:
Airborne radar is a bit of kit which starts at 50k and requires expert use and significant interpretation skills. But not many pilots who fly with the ones which actually work (and know how to use it) would say anything is better.
I have spent a career flying with airborne weather radar that works, most recently in the awful weather yesterday. It is good, but has significant shortcomings, most serious being, as Aviathor says, that it is very difficult to get a long range view when there is heavy precipitation in the short range, and that you can only see 35-40° off track either side, which does not allow strategic decision making.
I wonder how many of these large numbers of airborne radar using pilots you know have had the opportunity of comparing their preferences with ADL? My guess is that most of them fly CAT or heavy metal where there is no possibility of ADL installation.
It might be worth talking to pilots who have extensive experience with all systems instead.
not a verbalisation from ATC
OK; in the USA you can get the image upload which I thought is what you meant.
Aviathor wrote:
Last I heard this is not the case in France,and I do not know whether there are any plans to acquire that capability despite DGAC recommendations
The system we currently use is described in this pdf (page 4, paragraph III). The weather depiction is not on the radar screen but on a separate system.
So we can’t really know the relative postions of plane and convective cells.
It’s rather poor resolution (big pixels) and is updated every 5 minutes. It’s rather clear that we can’t provide remote weather avoidance with such system.
Following the BEA recommandation, our nextgen ATC system (expected 4 to 5 years from now) will have the weather overlayed on the radar.
But if the weather data feed stays that poor, it’s rather clear we won’t be able to provide weather avoidance.
Who could provide weather avoidance of embedded CB on a highly convective day with low resolution and 5 minutes old data ?
Going back to the OP – a couple of years ago, on a Traffic service in bumpy IMC, Farnborough LARS offered me avoidance vectors around some CBs ahead of us – even to the extent of taking us through Solent airspace, which the F’boro controller co-ordinated with them so we didn’t need to change frequency.
True, it was a pretty dire day and there was only one other a/c on frequency, so the controller probably had more time than usual, but I was still grateful for the help – F’boro controllers often get a bad press but credit where it’s due.
(It was also so torrential that my left trouser leg was soaked before I worked out that I needed to close the punkah louvre, but that’s another story).
Rich wrote:
my left trouser leg was soaked
Rich, I know it was scary but this concerned me greatly until I remembered not all aircraft are pressurised…. 
JasonC wrote:
Rich, I know it was scary but this concerned me greatly until I remembered not all aircraft are pressurised….
If my leg hadn’t been cold as well as wet I’d have thought the same thing!
Those who want to know what French ATC has at their disposal for weather information, some info here.
what_next wrote:
So yes, now I know for sure that ATC have an excellent weather radar and they can use it in the best possible way to steer light aircraft around ugly weather. If they only wish to do so.
But you wouldn’t assume they have it on your next flight, would you?
Sebastian_G wrote:
Average age of displayed radar data is the sum of:A) Half of data acquisition interval (~2.5 min)
B) Data processing and transmission time (~4-12 min)
C) Half of data update interval (~2.5-7.5 min)
Archie wrote:
Sorry I’m confused here, how long does one radar sweep take?
Stating that it can’t be transmitted quicker is ridiculous. One radar snapshot can be transmitted as a 512×512 .PNG (<10Kb) over the internet which takes 7 milliseconds.
It’s probably due to the fairly antiquated proprietary systems that are used.
No, there is a vast amount of processing that takes place on the data before it is distributed. It is not a sweep of a single radar, it is typically a composite picture of several including different slant angles. Processing is used to make it a fair view of the space covered. Your 512×512 png is derived from a very large complex data set.
Radar data is sold commercially, and they sell different feeds at different prices. Just like stock market prices. The European consortium charged with merging and marketing it used to be called Opera; not sure what the current one is. It was a monopoly created by European wx offices, to exploit their “property” commercially.
You can get 15 min radar for free from meteox.com (well, funded by adverts so meteox pays something to get it, I guess). Any faster and you pay seriously more. 5 minute data is probably a few k a year and that is what most wx pay sites offer e.g. the avbrief.com radar subscription. Faster still would cost serious money – too expensive for GA in general.
I too don’t believe for a moment the processing (CPU time) is the bottleneck.
