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RADAR: Section 1

 
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PostPosted: Mon Oct 27, 2003 6:33 pm    Post subject: RADAR: Section 1 Reply with quote

From: Mike (Original Message) Sent: 1/26/2003 8:58 AM

RADAR

Welcome to this corner of the pub. It is a round table, located back in the corner in the non-smoking section, behind the bar, with room for a bunch of chairs. If you've gotta go, raise your hand; If you've got a question, raise your hand; If you disagree, raise your hand. This ain't no lecture! There are many Brats out there with lots of radar experience, and although this pre-school is pointed toward the newbies, the whole gang is welcome and comments from the experienced folks are encouraged. If this doesn't develop into a give-and-take situation with lots of questions and answers -- I'm doing something wrong.

Even though a large part of my radar experience (since 1943 with very little recess time) has been in the radar navigation area, airborne and seaborne, I expect we will end up talking more about radar's safety capability - prevention of collision at sea. With the availability of the GPS/chart units, if you are fortunate enough to have one, the navigation chores are markedly reduced. Of course it is always wise to have a backup log, because all electronic gadgets can drop dead. I even carry a little back-up battery powered hand-held GPS.

Do you need radar? It's an expensive gadget, and if you install it, the International Rules of the Road (hereinafter "rules") require that you use it. (Rule 7). Many of our Brat skippers don't have radar and don't want it, and there are thousands of other boaters enjoying recreational boating without it. However, if you often boat in poor visibility, radar is a VERY useful safety aid - with one very important caveat - the term "radar-assisted collision" is a common term in my former profession, and the improper interpretation and use of radar has caused some "horrendous destruction and loss of life".

And that's exactly why we're here sitting at the round table, dear Brats, to develop the "useful tool" part of radar and avoid a "horrendous destruction and loss of life."

Personally, I'd feel naked and lose a major part of my boating if I didn't have radar, and I'm quite certain Jon (C-Lou) feels the same way. Fog and rain in my preferred fishing areas are givens. The radar's make and age are not nearly as important as the operator's capability and judgment. When I operated my charter boat out of Seattle, after leaving the locks in low visibility, the stress level was unbelievable. That was before electronic charts and GPS - all navigation by radar. Always dozens of dots on the screen, ferries, commercial freighters and passenger liners, tugs and tows, and small guys. Each was a potential collision, and had to be evaluated. Having the track on the chart and turn times and headings in the log took away some of the stress, but by the time I reached Juneau I was totally exhausted. How fortunate we are now to have available all of these new tools, and that same trip today would be a pleasure cruise.

You all know this, but I'll re-emphasize one over-riding point just to make sure. The rules make it clear, but even if you are sacked out in the v-berth area after a beer and great lunch, and your very competent buddy is at the helm - if something bad happens, you are the guy! Every life on your boat is your responsibility - and if your boat hits another boat, or one of your passengers fall's overboard and drowns, or, or, or… we all know where the buck stops. So stick around the table a bit, and let's learn together how to prevent the bad stuff.

- - - - -

Now to answer some questions.

My radar is a little JRC, will it do the job? I'm shopping for a radar, which is the best brand? And many more emails in the same vein.

The answers depend on where and how you boat. The little JRC radars have a good reputation. I've never owned one, but several friends in our area have them and like them very much. Up until very recently it was considered throughout the industry that transmitter power under about 2 KW was insufficient to penetrate heavy rain and squalls. Electronic technology has been growing exponentially and my last three radars, Furuno, Raytheon, and Simrad, all with 1.5 KW output, have been fine. If you don't get in heavy rain I think the 1 KW JRC would be okay, but I'd suggest a good operational check before you depend on it in the heavy wet stuff.

The radar brand to purchase is a personal choice. Furuno has dominated the field in the larger radars, but Raytheon, Simrad and many other brands are fine. When I was a dealer I sold more Furuno, Raytheon, and Gold Star than others - primarily because of service. My customers were all commercial users and downtime was lost money. Furuno and Raytheon service centers were quick on repair turn-around, so that's what sold. There were some dogs out there in the past, but I don't know of any now. The market place, particularly with all the internet information available, kills off the dogs in a hurry. My personal radar is a Raytheon, not because I think it is better, but because it is a part of very complex system and it will talk to all the other units easier. I'll report on it later when we get a chance to use it. Radar, two screens (one color), depth sounder, auto pilot, gyro stabilized compass, remote control, etc., etc. all talking to each other. All that, with the capability of over-laying the radar screen on the GPS/map to see which targets move (hopefully the buoys don't), and tracking a whole bunch of targets electronically to compute their course, speed, closest point of approach, and time… wheeeeee. What a toy!

Question: "Why do I need to study the rules when most of the small boats I meet don't adhere to them and the big ships ignore me?"

Good question, and I hope we will develop a lot of answers at the round table. As far as the big ships, we had better address that one a bit. A good radar reflector helps a lot, but there are as many variables on big ships as on our little guys. A first-line USN or USCG vessel will see you. The Navy ship will have a minimum of 2 or 3 full-time, highly trained operators on several scopes all of the time, and they can spot a tiny periscope in the water miles and miles away - plus they have all kinds of electronic gadgets that warn them of new targets and all of the new guy's parameters. Other ships, and particularly some of the mid-east and Panamanian registered ships, may or may not see you, and many of the fishing fleet won't. So here comes an answer you should remember - there will be a quiz. Question: Should I count on other radars seeing me?

In low visibility situations DON'T EVER RELY ON THE OTHER SHIP'S RADAR TO SEE YOU. Even if they see you they will probably appear to ignore you. If you have the right of way, and the rules require that you maintain course and speed, the big guy will almost always play chicken until you have to change diapers. You are MUCH better off, in low visibility situations, to avoid the big guys, and pass astern of possible. We will develop ways very soon here in the pub as to how and when to avoid that situation. In a fight outside our little pub the big guy usually wins - at sea the big guy usually wins and destroys the evidence.

So that's the first shot. Next session we'll start with recognizing when a "risk-of-collision" exists, and some of the things that are not contained in the rules that are potential traps. We should also talk about the rules a bit next time. For the purpose of this pre-school I'm using the International Rules. There are many others and when we get rolling along here another thread on State's Rules, Inland Rules, Special Harbor Rules, etc. might be a good way to go. It's my intent (not in concrete at all) to keep this as simple as possible for the newbies. I'm hoping to stay away from a detailed study of the rules except for those that directly pertain to radar and low visibility situations. The rules are written for large vessels, although they apply to all of us, and are difficult to understand and remember. If there is enough interest I'd be happy to escort the newbies through the rules in detail, or just do a pre-school on them with suggested reading. It's your call, guys and gals.

Want to keep going?

Dusty

From: Mike Sent: 1/26/2003 9:00 AM
Note: The above is the first in a series of articles concerning the use of radar on small vessels such as the C-Dory. The initial work was prepared by Les Lampman, Sr. (aka Dusty, Sawdust) and is based where appropriate on international rules and regulations, as well as various text books and published articles. The primary resource for this work, however, is the experience and knowledge gained by Mr. Lampman over a lifetime on the water, through a career that has placed him at the helm of most every size and shape vessel at sea, from the largest in the world to the boats we use ourselves.

The series will progress from this introductory installment through the intricacies of radar navigation, use and application. Rather than a lecture or how-to manual, it is a give and take process that relies on comment and question from its readers. The depth and detail of the information presented will be guided by the group. Each subsequent section will be posted to this Message Board in much the same way as this, with the body of knowledge covered by each logical section as the initiating post to a thread of discussion.

All are encouraged to participate in this unique and enlightening process by posting questions, comments, concerns, and additional information relevant to the various sections. The content of subsequent sections will be shaped in part by the discussion around previous entries, and the degree to which we delve into this complex subject will be determined by the participants through their contributions.

From: C-LionRay Sent: 1/26/2003 9:32 AM
Professor Lampman, Is it possible to use RADAR to see oncoming weather fronts?

I asked a question on another discussion regarding safety and the possibility of being blinded by a unit in operation, can you please address that here for all to see?

Are there gonna be quizes? What about a midterm? A Final?

Could you let me know when they are gonna be so I can take you next door before you grade my paper?

Err, I can't help it... THANKS FOR DOING THIS, YOU ARE THE GREATEST!


From: C-LionRay Sent: 1/26/2003 9:40 AM
Oh, I almost forgot, What special considerations should be made prior to mounting the Radome? How high should it be? What is the best "angle" to mount the dome on a "typical" C-Dory.
I have seen domes mounted right to the hard top and I've seen domes mounted on tall racks. Could you touch on the pros and cons and your recomendations?
I'll sit down a while now...

From: Jon Sent: 1/26/2003 10:44 AM

Dusty,

Cynthia and I are signed up for the class and eager to hear more. Yes, I agree about having a radar. In our "neck of the woods", it's saved my "bacon" more than once. I have some questions, comments, concerns, and will share them with everyone at the appropriate time. (Don't want to jump ahead too fast). I use the very basics on our Furuno 1800 and would like to know more. Very excellent point about everyone aboard knowing how to run equiptment and the boat. I've been neglecting that somewhat and need to improve. Thanks again, Jon

From: Blackfinn Sent: 1/26/2003 11:18 AM
Howdy,
What a perfectly timed topic. Last fall we bought a 2001 CDory that came with Raytheon radar, an SL70 unit if I recall correctly. Not something that would've been first on my list to purchase, but kind of fun to play with. And I just bought a Raymarine L760RC GPS chart plotter/sounder to match and for the heck of it, bought a SeaTalk cable to be able to connect the two. The trouble is I really don't know yet of what advantage it will be to do so. Perhaps you could explain what awaits me.
Thanks,
Al

From: Fun Patrol Sent: 1/26/2003 12:41 PM
Nice job Dusty. A couple of the rules of the road that I like are "Big over little", and "Steel over plastic". Smile

Roy

From: Fun Patrol Sent: 1/26/2003 12:43 PM
And of course......."Rock over steel".....

From: Sawdust Sent: 1/27/2003 9:47 AM
Roy,

Just got my computer back - frustration. Agree with you - we all lose, but the big guy loses less! The only bad collision I've been involved in happened on a beautiful sunny afternoon with 30 miles plus visibility. Gent T-boned me while I was dead in the water, engine off, working shrimp pots. He was sorry and so was I.

Dusty

From: Sawdust Sent: 1/27/2003 9:55 AM
Yep, Mr. F., you can see the weather that is associated with fronts coming through, altho I rarely do. My radar is usually set for less than 3 miles so I can avoid running into somebody - or them running into me.

I'll leave the answer to your installation question to Les. I've mounted them both ways - on a pedestal and on the roof. I personally like the radar mounted low in the boat because my concerns are the boats close aboard - the only time I'm in long range is to check the power output of the transmitter or receiver tuning. One of our biggest problems here in low visibility is seeing the kayaks soon enough to avoid them. They like to play in the heavy current in Deception Pass and are difficult to spot when the crests are breaking... so far so good.

Dusty

From: Sawdust Sent: 1/27/2003 10:05 AM
Jon and Cynthia,

Welcome - and Cynthia I appreciate your phone call, but I can't yet talk on the phone. I'm improving, and will give you a call soon - want to lunch with you folks in PA so we can visit a while.

Jon, agree totally with your "keep everybody involved" thoughts. I've had the opportunity to teach boating to many couples - in almost all cases the lady was better at holding a compass heading than the guy. (yes, I said that!) As all of the experienced radar folks know, it can get busy out there - somebody has to hold a heading, somebody has to watch and evaluate the radar, somebody has to keep the fog signals going, and somebody has to keep a sharp lookout for drift in the water and other boats that loom quickly out of the fog... AND, somebody has to call the CG if you have a physical problem. Most of the lady boaters I've known want to be involved - some don't. Bet C-Lou does!!!

Dusty

From: Sawdust Sent: 1/27/2003 10:13 AM
Al,

I'd like to pass your question on connecting your two units on to Les. He's the expert in the family on hooking this stuff up -- and there are some big advantages in connecting them. In my unit the waypoint information also goes on the radar screen, and warns when you approach the waypoint, plus adding a track line. Good idea, because you can then concentrate on the radar to look out for other vessels without having to check back and forth. Les will know your equipment, I do not. And welcome to the radar site -- we should have lots of fun here.

Dusty

From: Jon Sent: 1/27/2003 9:10 PM

Hey Duster,

I'll go ahead and start with some of my questions since I don't know what the next topics are going to be for the radar class. As most of my C-Dory buds know, I have the early 1980 vintage Furuno 1800 (And yes, it's as big as a house). This is the only radar I've ever used so bear with me. I almost always use the radar under a 3 mile range, most of the time 1 1/2 mile range. The only time I will deviate from the 1 1/2 range is when I'm far from the shore and want to get a land mass picture in the screen for reference or to see if any big ships are chugging down the strait.

Dusty, when turning the radar on, it has a one minute and forty second warm up period before it is functional. This is fine when I take off in the mornings and sometimes I'll shut it off when the fog rises. I do have a standby button and I use it if I think the fog is going to come back in soon. Sometimes I get caught by surprise with the fog and will have to turn it back on again; only to wait another 1 minute and 40 seconds. Sometimes this seems like an eternity when you start hearing ship engines from a distance. I probably should leave it on the standby mode but I'm unsure if this will cause a drain on the battery or harm the unit for long periods of time.

Question 1-Does the newer model radars have a warm up period for them or do they operate immediately when turned on.

Another thing that disturbs me is the tune, stc and gain. I used a black marker to mark these 3 functions for my 1 1/2 mile range. It seems to be really accurate at this range. I fine tune these functions on a clear day around other boats for reference. It seems like when I increase my range on the radar, I have to fool with these three functions to get a better picture of whats around me.

Question 2-Does the newer model radars have an automatic tune,stc and gain or do you have to adjust these functions with all the radars.

Question 3-Does the older model radars throw off any significant radiation.

And Dusty, Cynthia is a pretty sharp tack with the gadgets on board. Good thing, because I drift once in a while. Jon, on the C-Lou



From: Mike Sent: 1/27/2003 9:50 PM
A simple question, Dusty. I read with interest your statement that Rule 7 requires that once you install radar, you use it. If an installed unit goes haywire, and does not function, is the boat operator in violation if he continues to use the boat without removing or fixing it?

Mike

From: C-LionRay Sent: 1/28/2003 4:32 AM
Jon, I have a newer but still dated Furuno 1621 RADAR and it must warm up too.
I'm thinking that it is just part of the deal.
I plan to connect my GPS to it so I can see waypoints on the screen for reference.


From: "Nancy H" Sent: 1/28/2003 6:50 AM
Mike,
Rule 7b: Proper use shall be made of radar equipment if fitted and operational.....
I read this to mean if you got it and it works then you gotta use it.

Dusty, please correct me if I am wrong.

Larry

From: Sawdust Sent: 1/28/2003 8:33 AM
Jon,

The 1800 is a very good unit and you'll seem dozens of them still on commercial fishing boats, but the newer ones are better in lots of ways. Less power drain, less radiation, auto STC, Tune, etc. plus LCD daylight screens. The list is endless. I can't give you numbers re the radiation for the old 1800 - probably not bad, but I just don't know. My Raytheon is operational as soon as I hit the standby button, and think most of the new units are that way. I'll ask Les in a few minutes.

As soon as C-Salt is in the water and operational I'll zip over to Port Angeles so you can play with one of the new ones. (Bring a pole)... in fact we can get Cynthia to drive while you and I drink Moose Drool and eat cavier (yeah sure)... think I just got beat around the head and shoulders with a pony tail.

Dusty

From: stevej Sent: 1/28/2003 8:40 AM
Nice job Dusty, I've been relying on my radar Furno 1621 more this year coming back from fishing trips in the dark assisted with a couple of spot lights. Heading back last saturday night the fog set in thick and we had to turn off the main light because of glare. So12 miles down Multnomha(sp) channel to home with one low power light and heavy fog (maybe 20' visability). The channel is only about 300' wide meanders like a snake and is pretty much lined with old pilings and log jams on both shores.

Until Saturday night radar was somthing the boat came with when I bought it and was used because it was a new to me, to be truthful in the past I never thought of it as a navigation tool but more as a collision avoidance device and somewhat limited in that function because of the problems I've had with gosting images and the ability to pickup other f iberglass boats except at very close range.
I have newfound respect for radar now. Between it and the GPS plot trail we made made it home safely and with a low level of stress, of course it took us over two hours.

One bit of advice would be to use the unit enough in good weather to have a high comfort level with the operation and display quirks. I've found that radar display analysis on the river is a much bigger challange than when using it in open water. The more time spent observing the return display when you can see the object being reflected the higher the comfort level is when you can see nothing.

stevej



From: Sawdust Sent: 1/28/2003 8:44 AM
Larry,

You are right on. The (a) paragraph, "Every vessel shall use all available means appropriate to the prevailing circumstances and conditions..." leaves a pretty good loophole, I guess, if the weather is fine and radar would not prevent a collision. Many hungry admiralty lawyers would probably disagree. I normally boat with mine on and often in standby mode in good weather - and turn it on once in a while because my old tired eyes don't see boats nearly as well as the radar does. I catch myself seeing a target on the radar, then hunting for it visually -- wow! There it is! And I still practice a lot doing relative bearing measurements and that sort of thing.

Dusty

From: Sawdust Sent: 1/28/2003 8:57 AM
Thanks Steve,

And you must have read my mind! My next session will compare learning to use radar - to learning to golf. You don't spend four figures for a bag of clubs and go play with Tiger. I'll emphasize the driving range, putting green aspect - and really put the pressure on to get lots of practice in good weather.

One thing that comes with this course is hands-on instruction. Once C-Salt is in the water and operational I'll be happy to take skippers out here at Deception Pass and we'll learn together. Price is right - be nice - maybe a cool one after.

Dusty

From: LesLampman Sent: 1/29/2003 8:22 AM
Hi,

I've a couple of comments to add here:

The power rating of the radar is not the only factor reagarding its performance. They all send out their signals at whatever power they've been designed with but then they have to receive that signal and interpret it; that's where the rubber meets the asphalt so to speak and where the more expensive radars start to pay back the extra dollars spent to obtain them. And, an otherwise great radar is useless if it's so difficult to operate (mechanically and electronically) in rough water conditons or high stress times that you spend more time operating the radar than using the radar.

Mounting the radome is not a critical installation; most newer radars scan 25-degrees vertically and can be adjusted electronically for correct fore-n-aft alignment. Whether to mount the radar on the cabin top, on a 5" PowerTower or on a radar arch has more to do with convenience and aesthetics than performance. It is true, of course, that the higher the radome is placed the farther the unit can see but conversely, the higher it goes the more it moves around (thereby reducing performance) and in reality most of us don't use the longer range scales anyway; those scales are much more important to larger vessels that can not maneuver as well as we can and/or need lots of stopping room. When mounting the radome I usually try for a slight down angle when the boat is at rest, level at 6 to 8 knots and slightly up at planing speeds but I'd be the first to admit that this is splitting hairs; this happens to be what you get when teh radome is mounted parallel to the CD cabin top.

I've found that the CD has just a little more crown in the cabin top than will accommodate direct mounting without a base or shim. If you place the radome directly on the cabin top and really reef down on the mounting bolts you can tweak the frame of the radome which is not a good thing. For these reasons and aesthetically I tend to use a radar mount. I normally use the ScanStrut PowerTower because it looks good and is a high qulity unit. I like the way it routes the radome cable and it's base is smaller than the radar base and conforms to the C-Dory's cabin top well. Another mount is from Lilly; they work ok too but have a totally different look. A full radar arch is a good, if more expensive, option; escecially if you want to slide a dinghy on top of the cabin and under the radome.

To the best of my knowledge all radars still require a warm-up period; most of the new radars are in the 1-1/2 minute range. Most of the new radars draw very little power in the standby mode and are 'awake' instantly when you press the transmit button.

Operating the radar is a skill that is totally different than any others that we have developed for operating our sounders or chartplotters. It's an absolute mistake to assume that because it has a screen just like the chartplotter or sounder that it's as easy to use. While a chartplotter is essentially just an electonic version of the paper charts we're used to the radar presents a view of the world that is totally different than the way the human eye views things. For instance, with radar alone and no knowlede of the area one would assume that you couldn't come through Deception Pass; the Deception Pass Bridge is presented on the radar screen just as a solid rock wall would be. It takes a lot of practice to make the transition and that practice comes from having the radar on in fair conditions so that your subconscious ultimately "gets it". And since when you really need it radar is often used in high stress situations it's nice to know how to operate it without having to fumble with the operators manual or through the on-screen menus; ideally you should be able to operate it by touch and glances alone.

Les
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