CHIRP Narrative: In a previous report in 2005, a pilot had advised as follows:
Some radars, although type tested have a severe navigational limitation that I have observed, which I wish to bring to your attention.
I encounter a wide range of radars with very little opportunity to familiarise myself with their operation before I am using them in earnest. I receive regular radar updating training and know what I want a radar to do, but increasingly, I am unable to do so due the complexity of different knobs and menus that are used by all the various radar manufacturers.
I have over the years noted that there is a specific problem on a particular type of radar that I have encountered.
Navigating in my pilotage district, it is quite normal to pass a cable or two off prominent landmarks that are ideal for parallel indexing. One example requires passing a PI landmark at 2.2 cables and altering course at over 2 miles to pass this landmark. I therefore require at least a 3 miles range with a PI set up to pass at 2.2 cables. The particular radar has a limitation of not being able to bring the PI Line closer than the inner range ring i.e. 0.5 mile on the 3 miles range. This is not adequate for the above example – it is only on the 0.75 mile range or less that I can set a PI of 2.2 cables – but my alteration of course is at least 2 miles from my chosen landmark!
CHIRP liaised with industry groups to follow this up.
We were pleased to receive recently a follow-up report from the pilot . He wrote “I am pleased to report that having recently piloted a new ship fitted with xxx radars, the situation with parallel indexing has been vastly improved. The PI lines now have a minimum range of half the inner most range ring, whereas you recall it was previously the inner most range ring.……………………It took time but something appears to have fed through, thanks for your efforts.”