Considering these ideas of navigation.. What is your opnion on it?

[CatNewBee]

almost everything nowadays has a GPS sensor, the handheld VHF, the VHF with AIS, smartphones, tablets, computer with GPS mouse, all the plotters, even smart watches. And they use GPS, GLONASS, BDS.

The only risks not getting a position were when aliens attack the Earth with EMP weapons that kill all satellites or there is a massive solar eruption / magnetic storm or a gamma-ray burst of a dying star that hits the earth or a nuclear explosion near your position that may interfere with all kind of radio transmissions including GPS. No thunderstorm can kill all of your electronic devices at the same time, the only reason you lose navigation can only be, that most satellites are destroyed simultaneously.

All this will cause much more trouble than just losing a position fix.

Fortunately knowing in what ocean you are and that the sun rises east and sets west plus all major land masses cross the Equator at some point and most are in the northern hemisphere, you just need to sail North-West until hit land somewhere. Even if the magnetic polarity reverses on earth, you still can follow the sun in the morning and have it on your back in the afternoon and lso use the moon rise / moon set during the night.

In the very unlikely event, that the incident was caused by a collision of the earth with a asteroid, big enough to change the earth axis, well, there will be some exciting other effects besides losing position fix or magnetic orientation I guess, so enjoy the show, it will not last too long.

Anyway, everything that only affects some of the electric systems on board and does not destroy the 3 positioning systems globally can be for sure covered by a battery hand held VHF with GPS inside or a smart phone or a iridium GO (has GPS too) in your grab bag.

If I look at our boat, there are 2 chart plotter with GPS, we have one old as spare part, we have each a smart phone with GPS - that is most of the time useless on the ocean and therefore probably turned off - and safe, we have VHF installed with GPS, we have our hand held Standard Horizon with DSC and GPS to carry around (on passage also charged, turned off and placed in the grab bag), also navigation tablets and the board notebook with GPS mouse. So over 10 independent capable devices with their own power supply to make a position fix - besides AIS transceiver (USB port) that can be used to get position and the Iridium GO! that has his own GPS.

I would probably be more concerned of wet / missing paper charts than not having a fix.

Bur a old sextant is a cool gadget and very useful to impress the ladies.

[Adelie]

Originally Posted by CatNewBee

. . .
No thunderstorm can kill all of your electronic devices at the same time, the only reason you lose navigation can only be, that most satellites are destroyed simultaneously.
. . .

On what do you base the assertion that a lightning strike can’t kill all the electronics in a boat? For the sake of argument let’s assume a fiberglass cruising vessel which is what most of the folks here will have.

[CatNewBee]

Originally Posted by Adelie

On what do you base the assertion that a lightning strike can’t kill all the electronics in a boat? For the sake of argument let’s assume a fiberglass cruising vessel which is what most of the folks here will have.

Because they are not connected to each other, some are not even turned on. A Lightning may strike the antenna of the VHF and grill everything connected to it in the boat, including all on-board electronics and batteries. The smart phones, tablets and handheld VHF are not wired / connected to the system and will not get affected. If they are turned off, even magnetic induction will not affect them. Only devices that are in operation and where the lightning runs thru could be possibly damaged if your mast is not sufficiently earthed.

The safest place for a smartphone in this occasion is in your pocket. If the lightning strikes and destroys it, you do not need to care about it, you will not even notice it probably.

[GrowleyMonster]

Originally Posted by captwylie

According to my mom Booty was a very distant cousin. You are correct about the Singleton Shrimp Co. We lived in Freeport , Texas and my dad was the captain of one of the Singleton fleet for several years.

I see you have gone electric. My son has a 42ft sailboat that he plans to convert to electric. I am one of those do it yourself guys is this something a mechanical person can do or do you recommend having a complete install? I can remove the diesel engine.

LOL We are getting a bit off topic... my fault. So I will wrap it up here in one post. I started a thread when I first started my repower. http://www.cruisersforum.com/forums/...on-129944.html . I also have some info on my website, under the E-Boats link, www.growleymonster.com . Hope it is okay to post that link...



Anyway yes you can DIY. I did. But you need to figure on a year or two of study first. You don't just take a motor and couple it to the shaft, hook it up to a battery, switch it on, and go. It really is quite complex, and the e-boat designer is under a lot of handicaps, and has to make a lot of serious compromises and tradeoffs, even when everything is designed, matched, and installed for absolute peak efficiency. A turnkey drop in package is less challenging, and all the real engineering is already done for you. A professional installation is best for most folks who can afford it.



A 42 foot boat requires more power than my system. You are getting into an entirely different setup. First of all, boats 36' and under generally use a 48v system. At 42', you need to go higher voltage. Once you are over 50v, it makes more sense to go at least 144v. 96V as a minimum. 300V is not overkill at all. Higher voltage gives you higher efficiency due to lower current required to do the same work. I only mention 96V because a ME0912 motor or other 10kw to 12kw BLDC motor can be made to run at 96V safely, and Kelly makes sine wave controllers for this. Just remember, this is max 15HP sustained, maybe 35HP possible for a one minute burst. Typically this size boat is equipped with a 35 to 50HP diesel. Your best bet is a larger three phase AC motor such as is used in an electric car. And this motor will develop highest output most efficiently at well over 3000RPM so obviously a reduction gear is needed. You can go pretty far, or pretty fast, or have a reasonably small battery bank. Take your pick. But you only get ONE. A boat that size would normally have about 20 to 40 kw/hr of storage, and an extensive solar array, and a 20kw or so genset. Lots of batteries. Lots of room, lots of weight. If you only need electric drive for docking and stuff, you can get by pretty small. That is why electric is kinda nice for sailboats. For day sailing, a diesel instead of electric is just plain stupid. Want to be able to motor a long distance at hull speed? Forget about electric. In that situation, electric simply will not do. Most eboaters are content to glide along at 3kts or so, out of necessity to get any useful range.



If your son already has a working diesel, my advice is leave it there. When you weigh all the pros and cons, it doesn't make sense to pull a good diesel and replace it with electric. If it has a dead and unrepairable diesel, or no engine at all, it might be a good candidate for electric repower. If it has a raw water cooled Atomic or some such, maybe electric repower is a good option. If you just want to try electric, you can maybe mount a suitably sized pulley to the prop shaft, and belt drive it from an electric motor using a pump clutch to disengage the electric motor when not needed. Meanwhile you can run the diesel with the e-motor engaged as a generator, or as propulsion assistance, or disengaged. You can disengage the diesel and drive the prop with the electric motor, or use the trailing prop to turn the motor and generate a small charge for the bank. So you will be able to run near silently on electric, and enjoy the improved maneuverability of electric (no minimum idle, instant on, no warmup required, no idle running) power while still having the range of the diesel. You can keep your bank size down to a reasonable size since it is not the primary mover. The big bank can be useful for running appliances that you would normally not be able to use. A solar array can give you free energy that you can use in place of a small amount of the diesel fuel you would otherwise use. This would be a parallel hybrid system. It offers a lot of advantages in return for the added complexity. But do keep the diesel if it runs.


The one thing that you MUST learn inside and out is batteries and charging/monitoring/balancing/control/maintenance systems. I won't write a book here but you really need to be quite expert at your chosen battery chemistry to get safe operation and good lifespan out of the batts.



Feel free to post electric propulsion questions in the "It Begins" thread and I will answer there. We now return you to your regularly scheduled program.

[Adelie]

Originally Posted by CatNewBee

Because they are not connected to each other, some are not even turned on. A Lightnig may strike the antenna of the VHF and grill everything connected to it in the boat, including all on-board electronics and batteries. The smart phones, tablets and handheld VHF are not wired / connected to the system and will not get affected. If they are turned off, even magnetic induction will not affect them. Only devices that are in operation and where the lightning runs thru could be possibly damaged if your mast is not sufficiently earthed.

I wish that were enough.

The magnetic field around a lightning strike is high enough to induce electrical spikes in unconnected electronic equipment.

Disconnecting equipment is a start.

If you want to provide much better protection the equipment needs to be sealed inside an electrical insulator (a Ziploc bag will suffice) and that needs to be inside a metal box (an oven, cashbox or ammo container will suffice). Insulator outside the metal box is backwards. This provides much better protection but is not a garuntee against damage during a lightning strike.

[CatNewBee]

A metal box is a Farraday cage, it is sufficient for any lightning voltage, except it melts down.

[Cadence]

Originally Posted by GrowleyMonster

Any relation to Henry "Booty" Singleton? Probably the first shrimp fleet owner to integrate boats, processing, servicing, and wholesaling into one operation on a large scale. When I was a kid, the Singleton boats were all over the gulf.

I believe Singleton went tits up. Probably due to Asian imported shrimp?

[GrowleyMonster]

Originally Posted by Cadence

I believe Singleton went tits up. Probably due to Asian imported shrimp?

Probably several factors, including Booty himself passing on. Fuel. Insurance. Federal mismanagement. TEDs. BEDs. Tighter immigration enforcement. AND imported farm shrimp. A lot of companies, and a lot of individuals, ended up as "debtor in posession" to banks that didn't want to own a bunch of nasty old shrimp boats in the first place. A lot of guys just gave up and moved on to other things. Or as boats were lost, just never replaced them. A lot of families here in Louisiana own a boat and just barely manage to keep it up. Sort of like a hobby that barely pays for itself it you work really hard at it.

[Adelie]

Originally Posted by CatNewBee

A metal box is a Farraday cage, it is sufficient for any lightning voltage, except it melts down.

Of course it’s going to melt if you take a blowtorch to it.

During a strike it carries the magnetic fields around anything inside so there are no induced currents. There’s not enough energy in the magnetic field to induce melting of the box or anything in it unless the current path goes thru the box in which case everything was going to be fried anyway.

[GrowleyMonster]

Originally Posted by Adelie

Of course it’s going to melt if you take a blowtorch to it.

During a strike it carries the magnetic fields around anything inside so there are no induced currents. There’s not enough energy in the magnetic field to induce melting of the box or anything in it unless the current path goes thru the box in which case everything was going to be fried anyway.

Of course, unless you have a genset stashed in that faraday cage, eventually you will find that your protected electronic devices don't work anymore. Just sayin. I love navigating with phone or laptop, don't get me wrong. And I will very possibly never be in a situation where that isn't possible. Still, it is nice to know that I can still navigate with no electricity whatsoever if I need to, or just to prove that I can, or simply to help preserve the art and science of navigation. I think anyone who sails out of sight of land who does not attempt to learn the basics of navigation is irresponsible. Just my opinion and it won't change. Others are welcome to their opinions, even if they are wrong.

[Adelie]

Growley: I agree with you. Adelie

[CatNewBee]

Originally Posted by GrowleyMonster

Of course, unless you have a genset stashed in that faraday cage, eventually you will find that your protected electronic devices don't work anymore. Just sayin. I love navigating with phone or laptop, don't get me wrong. And I will very possibly never be in a situation where that isn't possible. Still, it is nice to know that I can still navigate with no electricity whatsoever if I need to, or just to prove that I can, or simply to help preserve the art and science of navigation. I think anyone who sails out of sight of land who does not attempt to learn the basics of navigation is irresponsible. Just my opinion and it won't change. Others are welcome to their opinions, even if they are wrong.

I see your point, nice to foster good old skills for fun and for a deeper understanding of navigation. It is like rubbing dry sticks to start a fire. And some of us probably still carry some in their pockets just in case the lighter does not work.

Practically it would be the last resort in case anything fails, but it is very unlikely to happen. Even the US navy no longer teaches / uses sextants as fall back, and they still learn starting fire with dry sticks in survival drills.

[Olddan1943]

When one says, "Learn to navigate", does that mean using a sextant ?
If so, how many folks even own a sextant?
How many use it routinely to maintain their skill?
How many rely on their sextant as their primary source for navigation?

IF one writes down their GPS position on their paper chart every 30 or 60 minutes just in case the GPS system goes down, shut off, or a lightning takes out all your electronics?

If lightening takes out all my navigation electronics at the same time my first thought would be "upgrade time", "hello insurance company?"

[CatNewBee]

Unfortunately you do not learn to navigate with a chart plotter and modern devices, nor use radar, sonar etc. They still teach compas, papercharts, deviations, triangulation...

I am not saying, it is wrong, just missing the important part you use 99.9% of your time on the water.

[Olddan1943]

I think I can still start a fire with two sticks assuming they are both "strike anywhere matches."