Humber Assault info request

[congerman]

Anyone using a 5m Assault with a 50hp?
I'm thinking about putting a 50hp etec on one and I would really appreciate any performance info.

Top speed with 3 divers, fuel consumption, time to get onto the plane etc
thanks

[9D280]

I can't comment directly on the Assault, but my old Seasafe is on a par with it with regard to weight & length - and was originally supplied with a 40.

When I got it, it had a 1970s rated 55, so probably only 50-ish at the prop. Performed fine. On paper, the Assult has a shallower V, so time to plane etc should be less than mine which being deeper V needs a bit more speed before it "lifts out". (going the other way, think of a flat bottomed boat - it will plane almost instantly).

I wouldn't expect any performance issues with that combo. Other thing is, if in the fullness of time you want to up-HP your setup, the bolt holes are the same between a 50 & a 75.

Hopeully you'll get an Assault owner along soon with "harder" data. In the meantime, I hope this helps.

[congerman]

Wow that was quick! Thanks very much.

[chewy]

Quick little boats, I found with the one that I used that if going slow in choppy water it would come over the bow.
Cheap and cheerful and 5m with a 50hp on will be ok.

[vjmehra]

We own a 5.5m Humber Assult with a 60HP 2-stroke Yamaha.

We top out at about 30 knots if travelling light, about 28 knots with 4 people on board.

In terms of planing, we struggle to get there below 12 knots (which is very annoying on the Thames now), it handles beautifully at 14-16 knots however, with very heavy steering at low speed, sub 5 knots.

In terms of fuel consumption, 30 litres can just about get us from Kew to Greenwich and back, approximately 3 hours at an average of around 12 knots, although our throttle is a bit strange at the mo, so thats very much acceleration then deceleration, so perhaps could get you further with better handling!

In short a newer 50hp engine should be perfectly adequate!

[congerman]

Many thanks

[congerman]

Originally Posted by chewy

Quick little boats, I found with the one that I used that if going slow in choppy water it would come over the bow.
Cheap and cheerful and 5m with a 50hp on will be ok.

Thanks chewy

[bosun]

Hi
I use a couple of 5 metre assaults one with a 40 honda injection and one with a 90 two stroke yamaha.
The main feature of the assault seems to be that the tubes are mounted lower on the hull than most other ribs, which means that the boat is easier to climb into from the water but that the tubes drag in the water at speed and give a bumpy ride in rough water.
Even with a 90 and the engine mounted high I'm only getting 40 knots on GPS.
However even with a forty four stroke the boat planes ok however many people are in it as long as you spread the weight around.
Hull shape is a fairly deep v ,I think the only drawback for use in rough water is the tube height.
Which is why the destroyer and ocean pro have the tubes mounted much higher up.

[wavelength]

we had a 4.3 with a 50 four stroke on it. Very quick and extremely horrible. The hull/tube shape is akin to a cathedral hull with all the disadvantages that go with them. Only advantage is that with the tubes deflated it doesnt take up much room. There are much, much better Humbers

[Pikey Dave]

I recall diving off an assault in the early 80's, very wet, uncomfortable & stuffed into every wave.

[congerman]

Thanks all.