Step 6 - Upper Load Stabiliser Straps
Please note the fit in the following images of an 80 litre backpack on a small Torso Length. This backpack is a Holiday 80 (80 litre – 90 litre) travel pack fitted to Yvonne with a height of five feet (5’) or 1.52 metres and a Torso Length of 42cm or 16 ½”. The recommended Torso Length range for this backpack is 50cm to 58cm, or 18 1/8” to 21 1/4”.
The best fit for Yvonne would be a backpack with an Small Torso Length backpack with an adjustment range of 42cm or 50cm and a Stave Length of 55cm. The 80 litre backpack with an Internal Stave Length of 65cm and a Medium Torso Length of 50cm is then 8cm longer than Yvonne’s Torso Length at 42cm. Yvonne's Torso Length is also 4cm less than the minimum acceptable range of 46cm for this backpack
To demonstrate fitting this length of backpack, we first begin by bending the upper 5cm of the Internal Stave length above the shoulder, away from the head at approximately 30º from the vertical. We then attach the Upper Load Stabiliser Strap anchor position 5cm lower on the backpack to achieve an effective fit. It can be clearly seen in the images below why it is necessary to fit a backpack within the recommended Torso Length range. The recommended minimum for this backpack is
46cm (after modifying the frame), which is 4cm longer than Yvonne's Torso Length
If the Upper Load Stabiliser Straps were to be pulling at an angle of more than 45º, the Shoulder Straps would pull up and away from the shoulder, put excessive pressure on the chest, pull the shoulder straps from the back and shoulder, and cause the backpack to ride up from the hips. The image on the right illustrates the problem.
When pulling at an angle of less than 45º, the Upper Load Stabiliser Straps would place the Shoulder Straps squarely on the shoulder, relieve excessive pressure on the chest, put the shoulder straps comfortably on the back and shoulder, and prevent the backpack riding up from the hips. To achieve this result, White Mountain Backpacks™ provides a facility to lower the Upper Load Stabiliser Straps pull position on the backpack. To do this, remove the Upper Load Stabiliser
Strap from the upper ladder lock buckle and attach the Upper Load Stabiliser Strap to the lower ladder lock buckle. This second ladder lock buckle is approximately 5cm below the original position at the top of the Internal Stave.
On the superseded SSS Harness, remove the Upper Load Stabiliser Strap from the ladder lock buckle and feed the Upper Load Stabiliser Strap through the yellow webbing approximately 5cm below the original attachment position at the top of the Internal Stave. Then reattach the Upper Load Stabiliser Strap to the original upper ladder lock buckle