tow vehicle

[Murflynn]

I've been thinking about this and i'm not great at maths. If the boat and trailer weigh 18 tonnes on a vertical 90' drop and the slip is estimated to be 12' . If I divide 18 by 90 and then multiply by 12 then I get a drawbar pull of 2400kg. Have been on net looking at maximum drawbar pull and there is an experiment at Harper Adams with a strain gauge between Land rovers series , 110 Defender , Discovery and a tractor. The traction coefficient for the Defender is between 0.9 and 1.1 of its weight ( accelerator to the floor on a loose surface with limited wheel spin and the tractor already travelling at 1.1mph ). The kerb weight of the Land rover 110 is approx 1930kg. I think that the coefficient will be lower at a controllable speed working on a slip. So I think it's asking too much of a 4wd. ( open to corrections ).

I think you mean that the slope is 12' in 90'. The calculations are correct insofar as they give the resistance to moving of a perfect friction-free trailer on non-distorting tyres up a perfectly even slope. We all know that is never the case. I suggest you add a significant factor to cover the need to overcome static resistance ('stiction') before the rig is rolling, friction losses in the wheels, additional resistance resulting from tyre deformation, etc. I would add 50% to be assured my rig was adequate.

Edited January 13, 2017 by Murflynn

[Graham Davis]

There is a table somewhere that gives you the "variables" to add to any formulas to calculate winching loads. It was something I had to look at years ago when I was going to do motorsport recoveries.

[ditchcrawler]

hello got a 50 ft narrow boat and my own trailer `need to pull my boat up a slipway incline about 12 degrees rise what road car would be strong enough to do this considering just in low gear

Have you seen this posting http://www.canalworld.net/forums/index.php?showtopic=89273&p=1944575he didn't have a tractor

[Murflynn]

the oil and gas exploration and drilling industries rely on skid trucks that can load and unload themselves.

 

perhaps OP should invest in a big Kenworth.

 

Edited January 14, 2017 by Murflynn

[ditchcrawler]

the oil and gas exploration and drilling industries rely on skid trucks that can load and unload themselves.

 

perhaps OP should invest in a big Kenworth.

 

texas_bed_side_view_2__large.jpg

But there are lots more horses there than in the video I linked to, just a pick up truck.

[Murflynn]

if you're gonna do a job, do it right, do it big !!

[tomsk]

[Murflynn]

bloody lucky the wall doesn't fall down.

[MtB]

 

 

Who is the music track by? FAR better then the original!

[Nicktheplumber]

Who is the music track by? FAR better then the original!

Have to agree with you . It's by Korn .

[WotEver]

Who is the music track by? FAR better then the original!

I thought exactly the opposite.

[cuthound]

I thought exactly the opposite.

Me too, unless you completely rearrange a classic and play it at a different tempo it will always fail when compated to the original.

[ditchcrawler]

This was Fox's pulling my boat out at 18 tons, the cooling fan is just in the water.