Autopilot Principles

One question I’ve always had about AP was how does it react when you grab the wheel? Can you steer around an object and then let go of the wheel and allow it to get back to its path or do you need to reset it?
 
clayhubler":1i8cbthp said:
One question I’ve always had about AP was how does it react when you grab the wheel? Can you steer around an object and then let go of the wheel and allow it to get back to its path or do you need to reset it?

Short answer is yes. The Garmin has their "shadow drive". It's suppose to temporarily put the autopilot in standby if you were to grab the wheel and steer off course. I say it's suppose to, as it never worked properly on my 25, I think due to the stiffness in the steering. (On the 25, it kicked in anytime the autopilot initiated a turn... It did work on my 22). However, that being said, I didn't care for that shadow drive as it would turn the autopilot back on very soon after you stopped turning the wheel, on whatever the current heading was, rather than back to your route or heading you were originally on. I removed the shadow drive from my system, so.... if I am on a route or a heading, and say have a log pop up in front of me, I just turn the wheel smartly and consistently (since the autopilot is still trying to stay on route or heading) until I'm around the log. Once I stop steering, then the autopilot will turn me back on course or back to the route. There is no extra pressure needed on the wheel, and the autopilot does not turn the wheel when it is in operation. So you won't feel any resistance. However, the autopilot pump is still trying to steer the boat, so if you don't consistently and aggressively continue turning your wheel, the autopilot will turn you back to it's heading or course. The other option is to just press the standby button, putting the autopilot in standby, and then steering as usual. Colby
 
Wth the Raymarine AP that little round heading knob act just like a mini wheel. I often find myself steering with it instead of the big wheel.
 
In my autopilots, I have used a remote control to "dodge" that is to make a deviation in course, around an obstruction, and then the boat will return to the selected course. You can also have the remote control the course-in increments of 1* or 10*. When using the "dodge" function, you are basically steering the boat with electrical steering. Many of the larger yachts don't have a wheel--especially at "stations" other than the master helm.--and even there may have steering with a lever or joy stick.

To my knowledge the Garmin auto pilot is the only one with "shadow" drive. It it very simple to "pause" the pilot steer, and then have the pilot resume.

Just because you have an autopilot is no excuse not to have eyes on the water and constantly scanning ahead, as well as watching the depth sounder and chart plotter. The auto pilot actually should allow for more time scanning the water.

I prefer to have two chart plotters, or one with a split screen displaying large scale and small scale charts. Look for the details in depths and obstructions, which may have been missed in route planning. Then there is the radar and AIS plots, which give you more dynamic information about vessels which may pose a threat of collision.
 
It is funny how my non-nautical thoughts have always had it that autopilots are really only useful for really larger boats but now I understand that they are almost mor important for small boats.
What happens in a following and quartering sea. I would think that the dance of broaching wold be considerable. Cody's would probably be easy to broach but easier to survive than deep vee boats of the same size.
Will the autopilot adjust for the competing forces in a following/quartering sea? Am I over thinking this again?
 
Donald Tyson":1h1d5uxx said:
It is funny how my non-nautical thoughts have always had it that autopilots are really only useful for really larger boats but now I understand that they are almost mor important for small boats.
What happens in a following and quartering sea. I would think that the dance of broaching wold be considerable. Cody's would probably be easy to broach but easier to survive than deep vee boats of the same size.
Will the autopilot adjust for the competing forces in a following/quartering sea? Am I over thinking this again?

When in heading mode, it simply steers a heading. In route or track mode, it will follow a route or track and will correct for drift. But it's not smart enough to correct to a heading for best attack on swells and waves. I have found the autopilot to be a great and almost necessary addition to my boat. Especially when I am single handling. It improves the overall safety of the operation. But, and this goes for aviation as well, automation is great, but don't let it drive you! Use it as a tool or second mate, but stay alert! "Now what's it doing" is said often enough to realize that! Colby
 
Most of the auto pilots I used did fine in heavy weather. A lot depends on the sophistication of the unit. But the "dumb" Bemar Coarse Setter Commercial Auto pilot we had on our full displacement 62' ketch handled the seas in all conditions. This included hurricane force winds and seas of 35' to 45' and breaking. We never broached in 6 days of very heavy weather. The boat was under a storm jib of about 300 sq feet of sail (normal working sail area was over 2000 sq feet), and we had the engine ticking over at about 1500 RPM--enough that we always had a good water flow across the rudder, no matter what the sea state was. I was more concerned about pitch poling--but the wave height was less than the LWL of the ketch. I would have put out Jordan Series Drogues if there was a concern of broach or pitchpole.

The pilot we had on our Cal 46 which was more of a semi displacement boat, was more sophisticated. and it did perfectly under sail or power, also in heavy conditions--but never hurricane force.

A good auto pilot will steer the boat better than 99% of helmsmen. There are auto pilots which take into consideration, the wind direction, and velocity as well as sea conditions. In the single handed Around the World racers, Those boats are on auto pilot almost 100% of the time--and in the Southern Ocean, in gale conditions plus most of the time.
 
I worked hard to justify not having auto pilot on our boat. Put it in a couple of years ago and so glad that we did. If we ever get another boat, I will justify the expense for another AP. Colleen especially loves it. When we fish for salmon off the west coast of Oregon, Colleen is the Captain on the water for the day. She sets the AP and we troll for salmon. When the fish is on, she slows the boat and it will hold a straight course for us until we get the fish in the cockpit. Colleen then goes back to the helm and uses the AP to put us on another fish or to turn a 180 degree and go through the same zone that held fish. I have found that using AP enables us to stay more focused on surrounding Boats and to what is happening around and in front of us in the water. Like Colby and others have referred to, using an AP property can make for safer travel.
 
" to save gas and noise"

I am not sure you would do either running a cdory on a kicker at almost full throttle vs a 90hp main motor at idle.

A modern 90 hp at idle is almost silent. I have a 225 hp honda on my27 cdory and I cant hear it running at idle. I can hear the water pump pissing over the engine. 4 stroke kickers are also quiet but not at 3/4 throttle which is what you have to run it at to have steering.

AS I said in the first post . What you are going to do with your boat will determine how you want to set it up. I think you are best served with a auto pilot on your main that also ties to you kicker via a bar. If slow cruising is you thing with some fishing this is the way to go. Garmin or Lowrance/simrad with auto route and keep you in the right depth, you can set minimum depth, as long as the charts are correct.

I have spent two hours or more on the kicker getting to a port after a main engine problem 3 times. yes you need to run it almost full throttle if there are any wind or current.

As far as needing a generator. most kickers 9 ph or bigger have alternators on them. My 9.9 did and my 15 does now. Look at models with power tilt and trim, they will have it. On the 22 I have used the kicker to charge the batteries while on anchor so I could start the main. Kicker should always have a pull start as well as electric start for that reason. 4 to 8 hp other do not have that feature.
 
Thomas it struck me funn, to each his own:
"the water pump pissing over the engine".

As for the rest of your post I must tell you that I state my ideas to learn. I do take advice and am thankful for your post.

I hope to set up for trolling. Thanks

Oh, What HP do you recommend then for a 22 Kicker? I Was thinking 9.9 as it would let me onto so many state and smaller lakes, thanks.
 
Donald Tyson":2q2ewqzy said:
Oh, What HP do you recommend then for a 22 Kicker? I Was thinking 9.9 as it would let me onto so many state and smaller lakes, thanks.
There are a couple of EFI 9.9s out there. Nice to not deal with carbs for an infrequently used motor.
 
Oh, What HP do you recommend then for a 22 Kicker? I Was thinking 9.9 as it would let me onto so many state and smaller lakes, thanks.

A very simple Tohatsu 6hp would suffice on a 22. I had one and was happy with it. Only 50 lbs, had it's own internal fuel tank (or you could hook it up to the boat tank), manual start, but no alternator. A 9.9 will offer you electric start and trim, and a small alternator, but weigh more, and it's still only going to push you at hull speed. (And it'll cost a lot more.) Colby
 
Any kicker from 5hp, small side , to 9.9 will work fine but, always a but, not all are equal. anything below a 8 is not going to have power tilt and trim or remote throttle for the most part. EFI is great and Mercury has that on their 9.9 motor bodies ( power head) but some of them and some of the other builder 9.9 EFi is really just a down tuned 15 power head so you have to look at that. Biggest difference is a 9.9 efi on 9.9 power head is x pounds but a 9.9 efi on a 15 hp power head is xxx pounds. The manufacturers all wanted to have EFI 9.9s but instead of building on they just down tuned the 15s. Gets confusing. That is what mercury did until they redesigned the 9.9 to be EFI. Now there are both on the market.

now about the 9.9 gets you onto lakes and parks. Depending on the lake it will if its your ONLY motor. Does not matter if you don't use the main motor, the fact that its on your boat will keep you off the lake. I like to fish a local lake that is electric only so I went with a buddy that has a electric trolling motor on the bow of his jet sled. We tilted up the main motor out of the water and just used the bow mount trolling motor. Someone, I think her name was Karen, called the wdfw and the cops and we got meet at the ramp. Long story short told not to even dream about doing that again.

So check you local regs.
 
In Pennsylvania you're allowed to have your main motor in the water for steerage but not turned on. Since Covid there's been metal enforcement on that and I had a guy go by me the other day with his 225 hp in the water pushing the boat at 40 miles an hour. It sure threw my drift boat around. If you go to electric only Lakes you're still allowed to have your big motor down in the water for steerage. I've seen so many people abuse these rules and I sort of wish they would go back to one motor only according to the horsepower limit and not allow boats in the lake with oversize motors.

Well I'm sitting here and I still don't have a boat. I find it easy to talk big though. L O L.
 
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