Navigation basics

[Bathbuoy]

Its an frightening idea that the skipper of a motorboat with 2.5m draft (how big are we talking?) would rely on an app to passage plan and perhaps consequently is unsure of navigation basics. Come on people how lazy and uninterested in doing things ourselves can we get

I'm sorry where did I say I have no knowledge of navigation basics? You really ought to establish some basis for making such assumptions before making such accusations. If you bother to read the original post nowhere does it say that the app was the only means of navigation planning, or that we even followed the suggested route. I was enquiring about a piece of software that I have aquired as an aid and was perhaps not using it correctly. Yes we have only had a boat for six months, and have been limited due to lockdown, but we have completed our Powerboat Level 2 course at the earliest opportunity that was available, and as a sea kayaker regularly cross over to the IoW and paddle in the Solent. So I am more used to paper charts and wondered why one of my first uses of electronics didn't match my expectations.

 

[James L]

Its an frightening idea that the skipper of a motorboat with 2.5m draft (how big are we talking?) would rely on an app to passage plan and perhaps consequently is unsure of navigation basics. Come on people how lazy and uninterested in doing things ourselves can we get

If I'm going somewhere new I always turn on the route guide on my Garmin.
I don't actually follow it, but it's great to have an idea of time of arrival etc and more importantly if it detours from my planned route I know to examine it more carefully in case it has picked up on something I missed.
Seamanship is using all the tools available for a safe passage.

 

[hinch]

Do you put your exact draft into navigation software or do you add a little extra or round it off just to be safe?

mines 0.9m so i round up to 1m just to give me a little overhead.

 

[john_morris_uk]

mines 0.9m so i round up to 1m just to give me a little overhead.

Or underneath....!

 

[Adios]

I'm sorry where did I say I have no knowledge of navigation basics? You really ought to establish some basis for making such assumptions before making such accusations. If you bother to read the original post nowhere does it say that the app was the only means of navigation planning, or that we even followed the suggested route. I was enquiring about a piece of software that I have aquired as an aid and was perhaps not using it correctly. Yes we have only had a boat for six months, and have been limited due to lockdown, but we have completed our Powerboat Level 2 course at the earliest opportunity that was available, and as a sea kayaker regularly cross over to the IoW and paddle in the Solent. So I am more used to paper charts and wondered why one of my first uses of electronics didn't match my expectations.

Where did I say you said or have no knowledge of navigation basics? More that I fear you might stop yourself from learning basics if you use an app.

I was despairing at the thought of someone with a motorboat of a size that has a 2.5m draft considering using a phone app to make a passage plan and navigate. I've not got that wrong have I? You say you are new to this, I bet the advice of 90% on this forum if they weren't too polite is don't use that app at all at least for some years. I could understand using it for a kayak but you say you used paper charts on a kayak? And now you have plenty of space for a chart you are progressing to having it all done for you in an app? Seems odd but anyway why on earth do we get so lazy with things (I'm not just talking to you). If you plot a route on a chart you might start to remember the names of buoys and channels and distances between marks. One day you might even know where you are by looking around. But that will never happen if you use an app for everything.

 

[Adios]

I think it's unfair of you to characterise the OP as "lazy and uninterested".

When I said "come on people" i literally meant all of us who use these things not just him.

On the contrary, we have someone who has joined a boating forum, presumably at least partly to increase their understanding of boating. And someone who has obviously critically evaluated the performance of the software and found it wanting, and come on here to check their understanding. I think that is exactly the opposite of "lazy and uninterested" - it's someone with a genuine interest, who is keen to understand and to learn.

He wanted help with how to navigate a motorboat with 2.5m draft (This must be a sizable MOBO right?) by app which I don't think is the same as wanting to "increase his understanding of boating". He'd have been happy with a recommendation for a better app and off he'd go.

If he joined the forum to understand and learn about navigation we should all be telling him to put the damn phone away and learn to navigate in a much more reliable way. Unless we say that he might otherwise just find another app and still learn nothing .

Sorry Bathbuoy I'm just bluntly speaking my mind please don't take offence. If you bought this large MOBO you need to learn some proper technique. Doing a powerboat level 2 does NOT now mean you are ready to cut every corner you can. Unless this is the RYA recommended method now in which god help us

 

[Never Grumble]

Coming out of Portsmouth at HW I’d be using the inner Swashway up to Gilkicker point. Plenty of water even with 2.5 metres draft. Then follow the coast and use the N Channel as others have said.

Just read that you qualified this as "at HW" ... I was going to point out that my Navionics App shows charted depths of less than 1m and that at low water in a 2.5m draft motorboat it might be a bad idea.

If you bought this large MOBO you need to learn some proper technique. Doing a powerboat level 2 does NOT now mean you are ready to cut every corner you can.

Not sure exactly how much chart work and tidal stuff you learn on a powerboat level 2 course, it's a start but like a kayak it has a relatively shallow draft and suspect the focus might be elsewhere. I suspect there are lots out there with less of a clue or desire to learn than the OP, so I think he probably deserve a break. Hopefully in learning some proper technique he's also read his seamans guide to the rules of the road

 

[Adios]

Not sure exactly how much chart work and tidal stuff you learn on a powerboat level 2 course, it's a start but like a kayak it has a relatively shallow draft and suspect the focus might be elsewhere.

A 2 day course with a little about navigation: buoy recognition, lights and shapes, what a chart looks like. No passage planning. I had to do one last year to use a safety boat and I don't remember any navigation really. Its called Powerboat HANDLING level 2 for a reason I guess, so as you say the focus is elsewhere.

 

[Never Grumble]

A 2 day course with very little about navigation, buoy recognition, lights and shapes, what a chart looks like. No passage planning. I had to do one last year to use a safety boat and I don't remember any navigation really. Its called Powerboat HANDLING level 2 for a reason I guess, so as you say the focus is elsewhere.

The cruising syllabus is probably more appropriate for a motorboat owner. I have a Yachtmaster offshore (power) but with experience went straight in at that level without doing any of the other stuff. We all have to start somewhere though.

 

[TonyR123]

I did my Power Boating with day skipper 5 years ago (?) and did all the paper chart work, lights, shapes, etc. As I boat in the med I haven't used any of the chart work, tide data, etc ever since. Def not used a paper chart since as all done within navionics. I have downloaded savvy navvy a few weeks back but only briefly looked at.

However now starting to do sailing in the UK so have to brush up on my tides, currents, etc. Still don't think I will use a paper chart though.

 

[Adios]

I did my Power Boating with day skipper 5 years ago (?) and did all the paper chart work, lights, shapes, etc. As I boat in the med I haven't used any of the chart work, tide data, etc ever since. Def not used a paper chart since as all done within navionics. I have downloaded savvy navvy a few weeks back but only briefly looked at.

However now starting to do sailing in the UK so have to brush up on my tides, currents, etc. Still don't think I will use a paper chart though.

Do you carry charts? It would be a good exercise to at least once a year for a refresher do an entire trip from passage planning to navigating using no electronics (other than depth perhaps). Nice little challenge for a change

 

[Adios]

Attached is our route from Gosport Marina to Swanwick Marina at high tide 1300 on 16th April. Our draft is 2.5m but even at high tide (4.5m)

Have you mixed up draft (depth required under the boat) with air draft (height of boat above water)?

 

[TonyR123]

I don't carry paper charts in the med. Just a ports/anchoring book. Not convinced (yet) I will need paper charts in the UK. Probably make notes if needed on any plotted journey. Having said that doing a refresher is no bad thing!

 

[James L]

The only time I've ever done a passage plan was doing the yachtmaster theory.
There's nothing that complicated in a mobo. I'll haul out the paper chart if I don't know where I'm going, make sure I know any dangers, see if there's anything specific I need to know about in one of the port guides etc. Then I head off in relatively the right direction, usually headland to headland.
It might take me a little longer as I give anything I don't like a wide berth, but I'd prefer my time boating rather than huddled over a map.

It might be different if I was travelling at 5 knots in the middle of the night.

I know a lot of the fishermen here and I can pretty much guarantee their paper charts don't see the light of day and their passage planning revolves around what food to buy.

 

[Alicatt]

We were more concerned with tides and tidal flow, yes we looked at the charts and planned our trips on them but much more attention was placed in what time the tides were so we could dive in slack water. We never had the luxury of electronic charts, it was all paper, I was the only one apart from the one commercial diver in the town that had a GPS back then, and even that was not that accurate with the Selective Availability still switched on.
Even in Sinclairs Bay you could find spots with up to 6kt on a spring flood and then some strong eddies close to the headlands.

With those we planned drift dives and provided boat cover for those underwater, I've dived along the underwater cliffs between Ackergill and Noss Head, not particularly deep just the rock wall passed in a blur as the tides were so strong, but still some fine dives along there, flood or ebb the tide only runs the one way with a flood tide the tide flows in the north of the bay and along the cliffs on the south with the tide flowing east then a big eddy off the south east side of Noss Head, then on an ebb tide it flows north past Noss Head and eddies around the headland giving an easterly flow along the cliff.

 

[gordmac]

At 5kn tides are very relevant, at 25kn not so much.

 

[Alicatt]

At 5kn tides are very relevant, at 25kn not so much.

Have you seen how quickly a rocky islet comes towards you when you are doing 22kn and the tide is coming from your port beam at 16kn?

 

[Restoration man]

Correct me if I’m wrong, but are we saying this app and others actually plots you a course based on where you want to go and the draft of your boat??? People always say it’s bad to rely on a gps , but at least before this function was invented you had to at least look at the map on the gps and decide the best route by looking at depths and channels , bouys etc ,and had to put some thought into it ,and by doing this you would lean the route before even navigating it , If my app had this function I don’t think I would use it , when I’m on the road in my car I genuinely rely on my sat nav 100% of the time and by doing this I don’t know where i am at all , if my satnav packs up I panic , and it’s all down to not planning my route , everyone knows I get lost in my back garden?? but out on the boat I aways know where I am because I planned the route myself , ok i might follow the gps but its the planning part thats important, without doing this you will never lean where you are

 

[gordmac]

Have you seen how quickly a rocky islet comes towards you when you are doing 22kn and the tide is coming from your port beam at 16kn?

Can't be many places with a 16kn tide?

 

[[70521]]

Can I ask a basic navigation question about using a plotter, in this case the Savvy Navvy app.

Attached is our route from Gosport Marina to Swanwick Marina at high tide 1300 on 16th April. Our draft is 2.5m but even at high tide (4.5m) the route takes us the long way round the deep water channel rather than cutting through North of the bramble bank.

With a 4.5m tide would just staying out of the green drying areas not give us enough water? It seems an excessively long route for us at high tide.

It's an app, in my opinion not a very good one, and working with the data it knows. The charted depth and your draft to create a safe route.

You need to apply your knowledge and intelligence. Add height of tide, set and drift to pilot your vessel through those waters. Which in my mind negates the use of apps. OK they are a useful sanity check and you are rightly questioning that apps sanity.

I've had an interaction with Savvy Navvy on Facebook, so they will answer questions. Perhaps it is worth contacting them and finding out why it routed you that way, It will add to your knowledge and work out if the £60 pa is worth it.

I chose not to spend the cash as I use a mix of paper and free Internet information and all Savvy Navvy admit to doing is pulling together different online data sources - easy money if you can charge £60 per year. Say 1,000 users that's a very profitable wee app.