Radar Reflector - when to hoist?

[rob2]

A US firm sells a "radar flag" allegedly approved by US Coastguard. However, there is no evidence that a flapping piece of material, however metallised, will enhance the radar return - its hardly likely to be aligned as a reflector on a regular enough basis to allow MARPA to lock on.

Rob.

 

[JohnTH]

Yep, this is going to run and run !

73s de

Johnth

 

[Trident 24]

Octahedral type must be in the catch rain orientation.

maybe I should go back & read it again, I thought that the Qinetic report recommended a 'double catch rain' orientation when sailing.

 

[JohnTH]

Please remind me what a double catch the rain reflector looks like.

73s de

Johnth

 

[VicS]

I thought that the Qinetic report recommended a 'double catch rain' orientation when sailing

What is that ?
The recommendations were:

6 Recommendations
· Based on the results of this report it is recommended that yachtsmen always
fit a radar reflector that offers the largest RCS practicable for their vessel.
· The RCS of the radar reflector should have a minimum consistent RCS of 2m2.
· The Sea-Me is the recommended product if power is available
· If power is not available then the passive Large Tri-Lens reflector is
recommended
· The 4” tube reflector is not considered suitable due to its poor performance. It
is also recommended that the 2” tube reflector is not suitable since the
performance of this target will be even lower.
· It is recommended that poorly performing radar reflectors are not fitted as it
is possible that the user could be lulled into a false sense of security believing
that their chances of detection has been enhanced.​

 

[Marsupial]

Apart from the LED power indicator, there is a second LED which flashes whenever the unit is active (responding to a radar paint). Although nothing is failure proof, if you're in an active area like the Solent then you'll see the unit is working as the VTS radars will trigger the RTE out to the Nab Tower.

Once away from land, however, many commercial ships switch from X band radar to the longer range S band, which will not trigger the RTE, so a passive reflector, although far less effective in S band, is a good idea too.

Rob.

Rob, read the quintec report there is NO passive reflector effective for S band, not even a little one.

We have just completed 2500 miless ish across biscay to the med, for 2 days we had no returns on the seame, but then nothing was showing on the radar either at 24 miles range. But when we did encounter a ship even if we were hundreds of miles off shore the seame chirped into life; warning us of its prescence.

Also we had no close encounters with large ships by day or night they all left us at least a mile of sea room some times more but never less.

Only once did I need to make contact with what turned out to be a day trip boat 100 miles north of Malta to clarify if he had seen us as he was approaching fast from dead astern - he had.

All in all the seame is worth every penny yes it works.

 

[JohnTH]

Oooer Marsupial was that a typo. Did you really mean active reflector for “S” band Radar?



73s de

Johnth

 

[Trident 24]

What is that ?

I was wrong, at the time that I read the Qinetic report I looked at other sources too.

The 'double catch rain' suggestion came from here:

http://www.novamarine.ca/RadarReflector2.html

and

http://www.novamarine.ca/PerformanceCharts.html

and

http://www.ussailing.org/safety/Studies/radar_reflector_test.htm

 

[Marsupial]

Oooer Marsupial was that a typo. Did you really mean active reflector for “S” band Radar?





73s de

Johnth

no I meant passive reflector for S band - the band width of S band is too big for a passive reflector that would be small enough to put on a ferry let alone a yacht. read the report.