long distance trip advice

Jack h · 21 July 2007, 23:20

60 4 stroke
5m humber assualt
Hoping to travel 60 miles in one trip.
When on the plane and going reasonably fast what speed gives you the greatest economy, lowest fuel consumption per mile, i presume the lowest speed while still on the plane?
Anyone have an idea what amount of fuel would be needed for this trip, i reckon arond 50 litres.
Never done any longer distance trips and was wondering if anyone had any advice.
thanks

Nos4r2 · 22 July 2007, 11:25

Quote:

Originally Posted by Jack h

60 4 stroke
5m humber assualt
Hoping to travel 60 miles in one trip.
When on the plane and going reasonably fast what speed gives you the greatest economy, lowest fuel consumption per mile, i presume the lowest speed while still on the plane?

A bit more than that-enough that waves don't knock you off the plane. Prob around 20 knots and keep the throttle as steady as possible. Realistically though it depends how fast you want to get there,how much bouncing you can stand and weather conditions.

Quote:

Originally Posted by Jack h

Anyone have an idea what amount of fuel would be needed for this trip, i reckon arond 50 litres.

Depends on load and MPG from your engine.Personally I'd carry at least 75(maybe more) if there wasn't anywhere you can feasably fuel up en-route.

Quote:

Originally Posted by Jack h

Never done any longer distance trips and was wondering if anyone had any advice.
thanks

Pace yourself so you're not worn out halfway through... 60 miles isn't that far though if you think about it.It's easy to do 60 miles in a days playing.

Tims Osprey · 22 July 2007, 11:41

I always take a spare jerry can full of spare fuel where ever i go (holds around 20 ltrs) is your tank 50 litres then? if so then a full tank should do you but always take spare fuel when cruising to be safe. wot always burns a lot more fuel so pace yourself and the boat for long periods as nos said, 20 knots on your boat and engine will be somewhere around about 4000 rpm in good conditions which should give you good fuel economy when cruising, of coarse this all depends on boat load as well.

wavelength · 22 July 2007, 12:03

Doubt that is enough fuel for safety. No such thing as mpg at sea or even gallons per hour if the weather takes a hand in things. What takes 25 litres in good weather will take perhaps double that or more if the weather turns nasty on you mid trip and you find yourself bashing into a head sea (which an assault is not good at doing), unable to get onto plane, climbing up waves and then down into the next trough, then climbing uphill again. Seen it happen here-major SAR job/fatalities/medal service rescue etc etc and the major factor was the weather turning bad suddenly and insufficient fuel reserves for anything other than a fair weather trip. A second tank with a connector or tap to swop over is far better than trying to pour from a can at sea in deteriorating conditions.

Nos4r2 · 22 July 2007, 12:34

Quote:

Originally Posted by wavelength

Doubt that is enough fuel for safety. No such thing as mpg at sea or even gallons per hour if the weather takes a hand in things. .

Fair comment Dave. I was expecting 75 litres to be around double what he'd need if he was cruising. I should have said so really.

Tims Osprey · 22 July 2007, 12:38

A second tank with a connector or tap to swop over is far better than trying to pour from a can at sea in deteriorating conditions. [/QUOTE]

Agreed but if your engine doesn't have quick release fuel lines like mine then a jerry can or cans is the best option, make sure you have a pipe that connects to the cans for quick safe refueling. off coarse weather conditions are a big factor in fuel consumption and journey time, so knowing what fuel to carry in good conditions for a cruise will give you a good idea of what you need to carry for more ambitious journeys for the future, but bear in mind the humber assault is an inshore rib.

Nos4r2 · 22 July 2007, 13:08

Quote:

Originally Posted by Tims Osprey

Agreed but if your engine doesn't have quick release fuel lines like mine

Has anyone made an engine without quick release fuel lines apart from the little ones that have their own tank under the cowl?

Tims Osprey · 22 July 2007, 13:15

Quote:

Originally Posted by Nos4r2

Has anyone made an engine without quick release fuel lines apart from the little ones that have their own tank under the cowl?

well i guess because mine aint got e'm

wavelength · 22 July 2007, 14:03

no criticisms intended -a jerry can is better than nowt i have done it in the past and one of our boats runs with spare fuel in a can-but its a ******* to do in anything of a sea. We have no connector at the engine end but I had m'mechanic fit a changeover valve under the front consol in the destroyer and another fuel line which can be snap fitted onto a portable 30litre tank which can live in front of the consol. So much easier and if you do end up far from home in a different marina as the portable tank is easy to take ashore for fill up. We do not know the details of this 60mile trip-are there any bolt holes to get into en route -or is it out to the open sea with no stops possible(like the 60 miles from here to the Isle of Man) -or is it along a coast with cliff faces all the way and no safe havens? If using two tanks set off on one tank and then changeover very early onto the second so that you know both are viable.
30 miles out to sea aint the place to find that the second tank connector wont work and is letting air in or that some muppet has put diesel in it when you wanted unleaded.

codprawn · 22 July 2007, 14:13

A jiggle syphon is a godsend for transferring fuel.

wavelength · 22 July 2007, 14:17

Quote:

We have no connector at the engine end

sorry - I mean no connector at either end-just plumbed straight into engine one end and water seperator/tank at t'other.

Tims Osprey · 22 July 2007, 14:18

Quote:

Originally Posted by wavelength

no criticisms intended -a jerry can is better than nowt i have done it in the past and one of our boats runs with spare fuel in a can-but its a ******* to do in anything of a sea. We have no connector at the engine end but I had m'mechanic fit a changeover valve under the front consol in the destroyer and another fuel line which can be snap fitted onto a portable 30litre tank which can live in front of the consol. So much easier and if you do end up far from home in a different marina as the portable tank is easy to take ashore for fill up. We do not know the details of this 60mile trip-are there any bolt holes to get into en route -or is it out to the open sea with no stops possible(like the 60 miles from here to the Isle of Man) -or is it along a coast with cliff faces all the way and no safe havens? If using two tanks set off on one tank and then changeover very early onto the second so that you know both are viable.
30 miles out to sea aint the place to find that the second tank connector wont work and is letting air in or that some muppet has put diesel in it when you wanted unleaded.

Good advice i may do the same with my engines, i know what you mean in a choppy sea it can be a hard work doing fiddly jobs, a spare tank with snap connectors would be much better, cheers

Biggles · 22 July 2007, 14:23

As has been mentioned transferring fuel at sea is a nightmare. I love jerricans but they are big heavy and made of metal that when bouncing around breaks things. Therefore I carry all my spare fuel in 5 litre plastic cans. They are easy to carry, easy to store and when bouncing around don't have the same impact as a full jerrycan. Reasonably easy to refuel in a rough sea as well. They probably have downsides.

Oh and they are totally legal to use in Petrol stations. Suprisingly 20 litre metal Jerricans are not in Hampshire. But 10 litre ones are

randski · 22 July 2007, 14:35

Have a look at Roy's trip in a Humber Assualt

http://www.rib.net/forum/showthread....ight=eddystone

BogMonster · 22 July 2007, 15:30

Quote:

Originally Posted by codprawn

A jiggle syphon is a godsend for transferring fuel.

thats what I use but I still wouldn't want to do it in anything of a sea because the fuel in the tank would slosh around and come out the filler cap and so would the fuel in the cans! it doesn't take much movement to do this when the can is fairly full

I use a syphon pump and carry 2 plastic cans (probably illegal in the UK) which carry about 30L each and don't rust! No HSE rubbish here

Biggles · 22 July 2007, 15:52

Quote:

Originally Posted by BogMonster

No HSE rubbish here

I'm just off to inform the HSE that the Falklands would benefit from a representative.

Best you post a lookout at the airport for a man arriving with a beard and patches on his jacket elbows.

Its not fair that we should have them all to ourselves.

NR.

Mollers · 22 July 2007, 21:28

Quote:

Originally Posted by randski

Have a look at Roy's trip in a Humber Assualt

http://www.rib.net/forum/showthread....ight=eddystone

Don't go there Bob.

Our lack of trips this year due to the weather is almost upsetting.

Jack h · 22 July 2007, 21:37

Thanks all for the advice, very helpful.
Nothing serious offshore, just coastal driving around anglesey, so obviously no issue with safe havens to drop into and places to refuel.
Know the waters and ports/beaches well so no issues there.
Thanks