Aerotec 380 maiden voyage

[chriswjallen]

Hi All,
I took my pre owned 2006 Bombard Aerotec 380 and 15hp 2-stroke Mercury for its maiden voyage on Sunday
I launched from Fambridge Yacht Haven in Essex and I have to say what a lovely environment, facilities, and everyone was friendly and welcoming
Took me about half an hour to unpack everything from the car, inflate using bravo BP12, put Zodiac Futura launch wheels on, and put all my gear in the boat etc.
Had a lovely time on the river Crouch and the boat and engine performed really well.
It was really fun and I feel a lot more confident having taken the boat out (I owe you all some photos; haven’t forgotten
However a couple of observations and challenges I wonder if any of you could help me with:

1) I left the transom drain bungs out while launching the boat but was a little alarmed to see water coming in while launching so I put them back in for rest of journey and until I drained the boat back ashore. No more water entered the boat while underway

My question is are these intended to be uni directional and thus potentially faulty? Or is it that yes a small amount will enter when boat is stationary but will drain when angle of boat steepens when underway? Advice and or tips gratefully received!

2) I found the zodiac Futura launch wheels a challenge to use. What is the ideal technique? I assume launching then tying to a pontoon and removing when in suitable depth of water and doing this in reverse on return? But what if no pontoon? And when underway, where is the best place to stow them? Again, any tips or advice gratefully received.

In summary, I was really impressed with the Aerotec and Mercury combination and it handled well and I felt confident despite it being somewhat breezy (15 mph south westerly). I cannot wait to get back out and next stop will be West Mersea in Essex following some great insight from Fenlander

Many thanks
Chris

[Fenlander]

Chris,

Great to hear you've been out with the new setup.

The transom drains have a crude flap valve and with the plugs out they will usually allow water to creep (or flow) in unless they are above water when on the plane... and even then the confused wake from an Aerotec can at time come in although they do usually drain far more than letting in on the plane. As a matter of interest I don't ever travel with the bungs out and just use them when lifting the boat at the bow to drain as we pull it up the slip.

I have the same Zodiac monster wheel as you. I never travel with them as we rarely need to pull out at any destination... I carry large inflatable rollers for the chance we get stuck in foreign parts.

So (bear in mind I always wear wet suit trousers) I push the boat into the water and when it's deep enough for the weight to be off the wheels I walk round to the transom and unbolt each wheel at a time putting them in the boat. Then I pull the boat (now with less draft) back to the slip lifting the bow just out of the water so it doesn't float away. Then give transom wheels to Mrs F who takes them to the car.

Reverse procedure at the end of the day.

My rollers are on post #45 of this thread...

http://www.rib.net/forum/f50/inflata...ers-67455.html

The only problem handling the Zodiac legs is the massive buoyancy of those large tyres making it a little difficult to push them underwater and find the lug posn. I solved this by changing to sandhopper type wheels which have a flat rubber tyre with no air and negative buoyancy... so much easier.

See my OCD driven search for my ideal transom wheels!

http://www.rib.net/forum/f50/best-wh...els-72495.html

Did you experience much of the dreaded Aerotec wake splashback?

David

[chriswjallen]

Hi Fenlander
Many thanks for the swift response
Noted re the bungs and those sand hopper wheels would make life a lot easier. Do you think they would slot straight into the OE Zodiac axels 25.1mm axels without any modification?
I was expecting the worst regarding the splash back but it was actually fine even at WOT. Incredible given how low the stern of the boat sits when in the water - my wife even commented on how low it looked
Thanks again for your advice
Chris

[Fenlander]

Mine are approx 25mm axles and the sandhoppers are a decent fit re dia. They are narrower than the OE Zodiac wheels on my set though so you can see I have added extra washers so they don't slide about the axle too much... 5 as seen in the image and 2 on the other side.

These are the type... https://www.ebay.co.uk/itm/2-x-Dingh...%3D&rmvSB=true

[Fenlander]

Re how low it sits in the water this is ours (leaving Brightlingsea to return to Mersea slip) at displacement speed with two adults, light teen and dog. Note to the left side of the image the black cone end cap is just going under the disturbed water of the wake.

[chriswjallen]

Brilliant, thank you Fenlander

[Max...]

Well done - superb combo and the best of the 2 stroke 15's IMHO - leverless tilt/trim and gear on the tiller is a joy! The Merc/Mariner 15 on a 380 like most 15's does normally need a 20 - 25mm batten under the engine clamps to lessen the splash and give best performance. Worth a try next time.

We never use the bungs - any water that gets in just comes out on the plane.

We nearly always leave launching wheels on shore.

Pic of batten and wheels here:

http://www.rib.net/forum/f50/making-...els-68175.html

[chriswjallen]

Thanks Max. Yes I’ve read about the batten but can’t picture it. Is it literally a piece 20-25mm timber between the clamps and transom plate? Or on top of the transom/directly underneath the engine so it sits higher?
Thanks again
Chris

[Max...]

See link above!

And more pics towards bottom of page here - just a wooden batten, sprayed black and siliconed to the transom so easy to peel off or whatever.

http://www.rib.net/forum/f50/rigging...c-71912-2.html

You cannot raise it more than that without major modding or the inner clamps will be too high on the inner metal transom plate.

[chriswjallen]

Apologies Max! Got it now

[Boatozzy]

Thought I would post on this thread as my query is similar. Today was my maiden voyage on our new Bombard Aerotec and I must admit I absolutely love it!! We were over at Brightlingsea and saw quite a few other Sibbers in the water.

I have a couple of niggles that I hope someone could help me with;

1. I struggled to find a comfortable position to sit in . I tried sitting on the tube and then kneeling inside with my body on one side of the tube. It would be great to hear how others sit in these

2. I found that at 2/3+ throttle water was flowing over the transom and into the boat. There wasn't the odd splash....... it was flowing in like a waterfall . Tubes were inflated to 3.5PSI and floor 11PSI. Outboard is Suzuki DF20 and I set the trim to the 3rd hole with 2 up. Does anyone else have this issue?

Thanks

[jeffstevens763@g]

Fenlander has same rig as you he will sort you out

[Fenlander]

This just shows the variation in setups, trim and loading... because I was gradually improving the splash issue with our Mariner 15hp 2-stroke and getting it close to a non-issue... then we bought the new Suzuki 20hp and the splash massively reduced to a point where on a whole day out it never needs baling.

If you haven't read about this previously...

With the V of the hull continuing right to the transom... and it having the particular shape you will see if you look at it underneath... the water flow meets as it leaves the hull behind the transom in a disturbed concentrated way. This water flow hits the front of the OB leg and at worse it can splash back into the boat over the transom.

The degree of splash varies with different OB leg designs and how far the OB is in the water. The amount the OB is in the water will depend on the OB make... boat loading... and trim settings.

The first mod most make is to add a small block to raise the OB on the transom as far as it can come up with the clamp buttons still sitting properly on the inner transom plate. We use a modest 20-25mm shim. Some folks have lifted the OB even higher by making a more extensive mod to effectively raise the transom by up to 40mm.

In doing any degree of OB lift you have to trial run to ensure there is no... or at least an acceptable... prop ventilation on turns.

Re loading and trim. I run in the central trim position. Our load trims the boat with the bow further down than many. Self on tiller... Mrs F on seat with full 25l tank under... heavy bag with anchor etc next to tank... medium dog in front of seat... light teen daughter is my moveable ballast** but she is usually on left tube just in front of seat.

So compared to someone solo... two up... without dog... smaller fuel load etc we run a far flatter trim so the OB isn't so deep in the water and I believe this keeps the splash to a minimum.

**when sea conditions dictate slightly more bow lift daughter moves to tube behind seat which give exactly the trim I want.

Re comfort... It's an issue that I never really think of. I'm 62 with a back that needs some care at times but average overall fitness and average-ish height of 5ft9in. I sit on the right tube which gives me a comfortable reach to the tiller.

[Boatozzy]

Thanks for the detailed post Fenlander. The issue you have described makes sense as there was a wall of water coming up over the transom and was only happening when I was close to full throttle (nice flat sea today ) I actually used drain plugs for the first time today and they worked a treat! They removed the water as fast as it was coming but I don't want to rely on them.

Our rig has 25L tank under the seat with Aerotec bow bag on the front carrying all equipment. Wife on the seat and me in the back. Next time we go out I will play around with trim and take a couple of sizes of wood to lift the outboard up to see if that solves the problem

[Fenlander]

So extra to your load we have 35lb of dog and 100lbs of daughter forward of seat. That could be the trim difference between ours effectively splash free and your splash.

As a matter of interest we run with drain bungs in all the while and perhaps mid trip** when crew are on a beach etc I'll stand at the stern to make the water run that way and sponge out a few pints that is normally dispersed under the air floor.

**Perhaps while at the café stop at Brightlingsea pontoon having come round from a West Mersea launch.

[Stevie Bill]

Sorry for the topic shift.. MODS please move if this post belongs elsewhere...
The transom waterfall is not restricted to one boat type.... My funyak390 with Tohatsu 20 suffers exactly the same, and there are various videos online of others with similar. An american patent shared by omc suggests at least one manufacturer recognises there is an issue... I am having a saddle built to raise the outboard as far as practicable, and will then try to fabricate a larger splash plate from hdpe as described in an earlier thread on this topic...
I think suppliers of outfits that have the problem need to be careful since a boat that takes on water like this is clearly not of merchantable quality. Different boat / engine combinations perform differently, but the supplier should ensure he is not providing an outfit with what appears to be a fundamental and potentially dangerous flaw! The fact that many boaters are inveterate tinkerers who will try to fix the problem for themselves does not detract from the suppliers duty...

[Poly]

Originally Posted by Stevie Bill

Sorry for the topic shift.. MODS please move if this post belongs elsewhere...
The transom waterfall is not restricted to one boat type.... My funyak390 with Tohatsu 20 suffers exactly the same, and there are various videos online of others with similar. An american patent shared by omc suggests at least one manufacturer recognises there is an issue... I am having a saddle built to raise the outboard as far as practicable, and will then try to fabricate a larger splash plate from hdpe as described in an earlier thread on this topic...
I think suppliers of outfits that have the problem need to be careful since a boat that takes on water like this is clearly not of merchantable quality. Different boat / engine combinations perform differently, but the supplier should ensure he is not providing an outfit with what appears to be a fundamental and potentially dangerous flaw! The fact that many boaters are inveterate tinkerers who will try to fix the problem for themselves does not detract from the suppliers duty...

Interesting Stevie. I genuinely believe I’ve never experienced this issue. Obviously I have a somewhat different configuration - with a centre console and a 2str 20HP. We get plenty of water over the front/sides but never the transom (although being further away I may not notice it very occasional splashing).

[Stevie Bill]

Poly... It seems that the transom overfall is only an issue for some combinations of boat and engine..... I would guess your engine has a larger splash guard plate than my Tohatsu (which seems to have a significantly smaller than other engines I have looked at). The boat itself may not be faulty. The engine may not be faulty. Put the two together and the outfit is very definitely faulty.

[Stevie Bill]

Oh... And I should point out... This not just occasional splashing. At speed, this is a steady, high volume inrush of water over the transom between the engine clamps. Several litres per second. Because it happens at speed when the boat is running high and almost flat, I don't think weight distribution in the hard boat makes as much if any difference as it seems to have done with fenlanders Sib. Certainly I have not been able to solve it by shifting my own not inconsiderable weight forward...

[Fenlander]

>>>The fact that many boaters are inveterate tinkerers who will try to fix the problem for themselves does not detract from the suppliers duty...

I'd agree. In the case of a new boat/OB package sold by a dealer I'd expect them to take responsibility for a combination that caused a constant filling up on the plane. Just being told to leave the bungs out wouldn't cut it for me.

I know it's hard to control the shape of poly boats absolutely when made... could yours and the problem ones have some sort of hull distortion adj the transom causing the water to throw up??