Topcat47
Well-Known Member
I was involved with an earlier DERA (pre QinteiQ ) study into Radar reflectors on behalf of the West Sussex Trading Standards Department. Like the later report we found the tube reflectors useless (and that was inside the anachoic chamber). Only the huge Echomax was capable of giving the required Solas signature and that dropped off markedly with angle of heel. At that time there was no affordable, effective Lunaberg lens, however the cyclops system ( an alternative lens design) was under development. Although the Cyclops was not tested by QQ, I believe it is still available and would have similar properties to the triple lunaberg lens tested. These two worked consistently at all angles of heel.
After testing in the anachoic chamber, the arrays were cut open. The tubes were found to be dihedrals not trihedrals, which was thought to be the clue to their ineffectiveness. Two of the stacked arrays (the smaller ones) were so badly constructed that the arrays were distorted inside the containers, contributing to their poor performance. Once straightened, the arrays performed better, but none were as good as the cyclops development model. The largest Echomax was found to be well constructed.
Having been associated with the earlier study, I concluded that permenant fixing of trihedral (arrays are also trihedrals) reflectors was a bad idea and that they should be mounted so that they may swing freely, at the crosstrees perhaps.
I have a Cyclops 3 at the masthead on a 26' cruiser, but these days I would look to the triple lunaberg lens as it is lighter. I would not have any other.
Transponders are best if you have a reliable electrical supply, but volts are a valuable commodity on my boat and as has already been said useless when a fault develops.
As an aside, When removing a large stacked array reflector from a dutch sailing barge,some years ago, if fell from the hands of the workmanup the mast and split open on the deck. It was found to be full of rainwater, hardly conducive to it's performance as a radar reflector and quite hazardous to those of us on deck.
After testing in the anachoic chamber, the arrays were cut open. The tubes were found to be dihedrals not trihedrals, which was thought to be the clue to their ineffectiveness. Two of the stacked arrays (the smaller ones) were so badly constructed that the arrays were distorted inside the containers, contributing to their poor performance. Once straightened, the arrays performed better, but none were as good as the cyclops development model. The largest Echomax was found to be well constructed.
Having been associated with the earlier study, I concluded that permenant fixing of trihedral (arrays are also trihedrals) reflectors was a bad idea and that they should be mounted so that they may swing freely, at the crosstrees perhaps.
I have a Cyclops 3 at the masthead on a 26' cruiser, but these days I would look to the triple lunaberg lens as it is lighter. I would not have any other.
Transponders are best if you have a reliable electrical supply, but volts are a valuable commodity on my boat and as has already been said useless when a fault develops.
As an aside, When removing a large stacked array reflector from a dutch sailing barge,some years ago, if fell from the hands of the workmanup the mast and split open on the deck. It was found to be full of rainwater, hardly conducive to it's performance as a radar reflector and quite hazardous to those of us on deck.
