radar reflectors

I don't understand refueller's blast at the RIN. Is he confusing the Ryal Institute of Navigation with the old Royal Indian Navy, or even (God forbid) the Royal Navy.
The RIN is very much concerned with technical advances in navigation and generally the multi-meter has replaced the marling spike.
Unfortunately the German cargo ship episode is not isolated. The publication of Accident reports is often made internally because of legal implications. It makes horror reading.
A little earlier than this I had to board a Greek ship which had called at Gibraltar for repairs. Bound from Crete to New York, she had only 3 charts on board as the capatain had to buy his own charts. He navigated mainly by a mixture of GPS and Traverse tables, with a pilot at each end. I gave him some charts. It was easier than having a scene.
 
I'm having a 'dig' at you, as it appears you are holding onto the old Colonial attitude that pervades too much of "British" Shipping Circles.

I am well aware of the RIN and it's role / wish to develop Shipping & Navigation matters. I am also aware of it's other side where it resists evolution.

I worked with a "Qualified" "RIN quoting" Marine Surveyor - he didn't last long. The exam paper he'd sat for his qualification was a joke. It was based on two questions : a) incident involving pilot ladder, b) cargo contamination.
He had to write so many 000's words in total.

And my post highlighted your insistence as Pilot, the demise of Red Ensign etc.

Charts .... UK Flag vessel, UK officers and Master, UK manning office, Management .... carrying sterile Fish Meal for discharge West Coast of Ireland. Chart coverage ended just past Rathlin Island in north, just past Cork in south. Navigation completed by using Admiralty Chart catalogue.

I was Ch. Off on it.
 
One thing has always puzzled me about radar.

Why did it take hundreds of millions of dollars and years of research to develop the "stealth" fighter that made a vastly reduced radar signature when it appears any old GRP yacht with a 40ft alloy mast, metal toerails and several vertical stanchions manages to be quite invisible to radar.

Somehow doesn't add up to me.
 
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One thing has always puzzled me about radar.

Why did it take hundreds of millions of dollars and years of research to develop the "stealth" fighter that made a vastly reduced radar signature when it appears any old GRP yacht with a 40ft alloy mast, metal toerails and several vertical stanchions manages to be quite invisible to radar.

Somehow doesn't add up to me.

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Actually, the great big hole in the water is a pretty good reflector as well! And if I recall correctly, the main thing about the Qinetiq report is that a) radar reflectors don't work very well under good conditions and b) don't work at all when under adverse conditions - like a 15 degree heel! That's how I read the report, anyway. Radar reflectors ONLY work if the reflecting angles are VERY accurately made and maintained and if the radar beam strikes them within a fairly narrow range of angles.
 
Probably showing that i don't know the first thing about radar..I'd tentatively suggest that GRP boats get lost in background clutter, its not that the radar doesn't see them, it just can't distinguish them. Up in the sky your GRP plane would be a more isolated object and show up better..but then I recall someone talking about Gliders being 'invisible' so maybe I'l shut up snd let the experts slog it out.

I once spent 30 minutes on the bridge of the Canberra (as nosy passenger) near the Channel Isands and quizzed the OOW about what was showing up on the radar...I couldn't make head nor tail of it. /forums/images/graemlins/grin.gif

Tim
 
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Probably showing that i don't know the first thing about radar..I'd tentatively suggest that GRP boats get lost in background clutter, its not that the radar doesn't see them, it just can't distinguish them. Up in the sky your GRP plane would be a more isolated object and show up better..but then I recall someone talking about Gliders being 'invisible' so maybe I'l shut up snd let the experts slog it out.

I once spent 30 minutes on the bridge of the Canberra (as nosy passenger) near the Channel Isands and quizzed the OOW about what was showing up on the radar...I couldn't make head nor tail of it. /forums/images/graemlins/grin.gif

Tim

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GRP is transparent to radar - that's why radomes are made of it! And why the biggest reflector you boat provides is the hole in the water.
 
[ QUOTE ]
One thing has always puzzled me about radar.

Why did it take hundreds of millions of dollars and years of research to develop the "stealth" fighter that made a vastly reduced radar signature when it appears any old GRP yacht with a 40ft alloy mast, metal toerails and several vertical stanchions manages to be quite invisible to radar.

Somehow doesn't add up to me.

[/ QUOTE ]

I like it ...

Bit like the old joke : NASA spent miilions designing a pen that would write in zero gravity ..... Russians used a pencil.

Stealth as I was told by Stealth pilots at Dahran / Sakananya during Gulf War 1 - The technology is not so much to be invisible, but to absorb and disperse the radar energy that hits the airframe. My question to them was based on I could not see how the angular flat surfaces against curves of normal airframes could do it.
Don't forget that Stealth is also referring to heat signatures as well. We Public people tend to only consider the radar aspect.

I'm sure there's a forumite who can give better than I 3rd handing a US pilots version !
 
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I recall someone talking about Gliders being 'invisible'

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Way back in 1940, when we were all getting twitchy about invasion, it was wondered whether wooden gliders would be spotted by that new invention, RDF. (Radar was a much later American term). So a sports glider, I believe an Olympia, was towed out to sea, halfway across the channel, then released to fly in as a target. Apparently it showed up quite clearly; the suggestion was that the control cables acted as resonators.

The interesting bit was the tow aircraft; probably the only time in WWII that an Avro 504K was flown operationally!
 
"Stealth as I was told by Stealth pilots at Dahran / Sakananya during Gulf War 1 - The technology is not so much to be invisible, but to absorb and disperse the radar energy that hits the airframe. My question to them was based on I could not see how the angular flat surfaces against curves of normal airframes could do it."

I'm sure thats the case.

But it still leaves the question of how a small GRP boat, in fact a whole range of small GRP boats, manage to achieve the same effect without the top secret materials and paint and shaped panels.

Like the "hole in the water" theory

Does a steel boat leave a different shaped hole?

And for that matter, how can a radar reflector make a difference to the shape of the hole?

It seems the more I read the less I understand
 
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