Transporter Ladder Bridge

This is a bridge for a reasonably wide stream. It needs to be built from both sides.

Equipment

• 6 x 5m (15ft) spars
• 2 x 7m (22ft) spars
• 6 x 3m (10ft) spars
• 2 x 2.4m (8ft) spars
• 3 x 1.2m (4ft) spars
• 30 x 0.9m (3ft) spars
• 2 x 15m (45ft) ropes to be used as handrails
• 4 x 10m (30ft) ropes to be used as guys
• 1 x 20m (60ft rope
• 1 light throwing line
• 8 pickets
• Maul or sledgehammer
• 60 light lashings

Method

A team on each bank starts by building a trestle using 2 x 5m (15ft) spars, 3 x 3m (10ft) spars and 1 x 2.4m (8ft) spar as in diagram (a)

The trestles are lain on the banks, facing each other, the butts towards the stream.

The guy ropes are tied to the top of each leg using a round turn and two half hitches.

Slide the trestles into the stream so that the butts rest at the bottom of the bank. Push the trestles upright, and then past the vertical so that they are leaning towards the centre of the stream. Peg out the guys to hold the trestles in place.

Throw the light line across the stream and use it to pull the 20m (60ft) rope across. The rope must rest on the cross members of the trestles.

Place the two 7m (22ft) spars together and tie one end of the 20m (60ft) rope to both of them and use it to pull them up, over the trestles, until they span the stream resting across both trestles.

The team on each bank then needs to construct a ladder using 2 x 3m (10ft) spars and 8 x 0.9m (3ft) spars.

Rest these ladders on the top cross members of the trestles, so that a Scout can climb up carefully and lash the 7m (22ft) spars to the cross members, approx 1m apart.

1 x 1.2m (4ft) spar is lashed on top of each end of the 7m (22ft) spars, close to the trestle. Ideally, the third 1.2m (4ft) spar should be lashed in the centre of the 7m (22ft) spars but you may have to use some ingenuity to reach this.

Reposition the two ladders so that they rest on the 1.2m (4ft) spars and lash them so they will not slip.

Prepare another ladder using the remaining 2 x 6m (15ft) spars and the remaining 0.9m (3ft) spars. This ladder rests over the 2 x 7m (22ft) spars, on the 1.2m (4ft) spars and is lashed in place.

Drive the last 4 pickets in, two at each end of the 3m (10ft) ladders to act as posts for the rope hand rails.

Finally, string the handrails between these pickets and the top of the trestle legs.

Note: Since the design of the project the principles of Health and Safety have changed dramatically.
Caution should be exercised to assess the risks associated with this build and especially regarding possible falls from height, so handrails or belays and harnesses may be required.

To download the complete plan and design document please Click Here