Towing a rib

[Roy54]

Does anyone know if its legal to tow a rib with a full cover on it? A while ago I towed it in a rain storm without the cover and the foam in the seats took ages to dry out. My cover is a heavy duty vinyl with 12 tie down points. Thoughts?

[harrison]

Nothing legal against towing with a full cover on.

The plod will only take an interest if loose, flapping, and a danger to other road users.

[sonny1]

when i bought my rib i also got a cover thinking i would travel with it on the rib , however when i mentioned it to my my supplier he looked aghast and told me not to tow with the cover on. im now putting my tin helmet on and awaiting the incoming brick bats. but thats what he told me!!!!! i should add that he was not speaking from a legal viewpoint.

[harrison]

sonny,

I’m with your dealer here and personally wouldn’t tow with a cover on. Any flapping can and will mark the tubes.

However, mines a lightweight material but Roy mentioned his was heavy duty with plenty of tie down points, so might be fine.

[Roy54]

I had thought about the movement of the cover on the tubes doing damage, but then the 4x4 punches a fairly large hole in the air and I think there might not be any more movement than a stormy day parked up.

[Salty Pete]

I had thought about the movement of the cover on the tubes doing damage, but then the 4x4 punches a fairly large hole in the air and I think there might not be any more movement than a stormy day parked up.

'tis the hole that a vehicle punches through the air that is one of the problems.

High pressure moves towards low pressure, that is the way winds are formed (watch the weather man)

Under your tarp you have normal atmospheric pressure. When your vehicle is moving it does punch a hole in the air, this is called a partial vacuum, meaning it is less than atmospheric pressure.

The higher pressure under the tarp tries to move up to equalise the pressure and can rip the tarp off the boat. This of course depends on the strength of the tarp, or the strength of where it is tied.

Of course wind causing flapping down the side has to be taken into consideration for RIB damage as well.

I take all equipment such as life jackets out of my RIB before I tow it. They don't get blown out, they get sucked out by the upward motion of the air in the boat.

[Roy54]

Superb answer @Salty Pete!

I towed our dory from Essex to Poole with the cover on and the flapping caused the eyelets to mark the boat in many places - the cover seemed tight and the amount of movement on the eyelets can have been more than a few millimetres but it didn’t half mark it.
Now, being fibreglass it was merely annoying as all I had to do was flat it back with some wet and dry sandpaper and polish it to a shine with T-Cut. This would not work with tubes!

The only time you will ever see covered ribs being towed is when they are being shipped and they are covered in what is essentially a heat-shrink wrap which is as tight as a drum (I have seen the RNLI ship ribs this way on the back of a lorry)

So I guess you could wrap your whole boat in clingfilm, but I’m not sure that is a responsible use of single use plastics!

In short - don’t tow with the cover on as it will damage your boat. I would cover your seats with something - surely you would want them to be waterproof anyway?

[Mitch]

Okaaay, I seem to be on my own here as I always tow with the ducks back on the boat.
Never had any problems with pressures or damage, better fuel economy as the boat is more aerodynamic with the ducks back up & over the engine.
Not sure about all these atmospherics, aren’t they the things that make thunder & lightning, as I’m going down the road at about 70mph shouldn’t there be a cloud just over my boat

[PeterM]

General advice is not to tow with a cover on. The aerodynamics involved are complex and down to car shape, boat shape , and cover shape . The smallest of movement can mark & hole a tube easily …


At any legal towing speed ( 60mph max) I'd say its asking for trouble unless you are lucky ( like mitch ) with shapes and pressures generated …. let the air flow and accept if it rains things get wet ( decent boats will actually be waterproof )

[harrison]

Okaaay, I seem to be on my own here as I always tow with the ducks back on the boat.

@Mitch you rebel you!

Course, we all know the real reason for towing covered....gotta keep the Fisheries men from clocking his massive haul!