In recent times the lightweight movement has made a lot of progress with regard to packs, much of the momemtum coming from the USA where light and ultralight packs are well established.
We have abandoned our bombproof but heavy Lowe Alpine packs and adopted a more flexible strategy to suit our differing load carrying abilities and varying requirements for the seasons of the year, and in doing so we have saved a lot of weight with no loss of comfort or functionality.
Most packs that can really be called lightweight are not commonly available in UK outdoor shops (although progress is slowly being made on that front), but a few specialised shops are stocking some. There are more possibilities with internet-only retailers, some of which were encouragingly started by outdoor enthusiasts, but in the case of backpacks I would personally never buy one without trying it properly for fit (see below).
My pack for joint trips is now the Golite Quest pictured above right and reviewed in the Gear & Tech / Equipment subsection, quoted at 72l and weighing 1.4kg, over 1kg lighter than the old Lowe Alpine. This is very light for a pack with a supportive moulded back system.
For most of the year outside winter the second pack is an old Karrimor Kimm Run 35 pictured above left, a slightly larger version of the classic Kimm marathon pack, very light with a mesh lid and pockets, good back padding for the size and zipped hip belt pockets. This is a very good light pack and clings like a turtle shell.
For winter we need a bit more volume for the extra insulation requirements, and for the second pack we now use the Golite LiteSpeed pictured right and reviewed in the Gear & Tech / Equipment subsection, quoted at 49l and weighing 1.1kg, again well over 1kg lighter than the old Lowe Alpine. This has the same moulded back system as the Quest.
For solo trips I use the Golite LiteSpeed most of the year and the Golite Quest in winter.
Many ultralight packs are now made in fabrics that are quite thin and light but tough, and with care general durability is not an issue. The lightest ones however are very minimalist and don't have supportive backs at all in the usual sense. They rely on a light load and careful packing, using a folded sleeping mattress for cushioning against the back.
A well known example is the Golite Gust pictured right with a capacity of 58l (+17l extension collar +4l pockets), that is quoted at an amazing 560g for the medium size.
The intended usage of the pack plays a part in the choice. Ascending into the hills for a quick one-nighter, or to do day walks from a base camp, are scenarios where the pack will not be worn for very long and comfort may not be critical, and a thin ultralight pack may be adequate. At the other extreme, on long distance treks covering 15-20 miles per day, comfort is of paramount importance and is worth a certain amount of extra pack weight, though it doesn't have to be much.
Choosing a first pack presents the usual problem - you really need one to gain the experience required to make an informed choice in the first place. The capacities quoted by the manufacturers don't really give any clue about what items will fit in the pack and some of the figures seem dubious in our view. Some include bellows pockets and some don't, and some are more sensibly given as two or more figures, one for the main body and the others for the pockets and extensions, but none of the figures are intuitive. The ideal pack is unlikely to be found first time anyway, as ideas and techniques evolve with experience. Also the weight and volume requirements are different in summer and winter and the optimum solution will probably be two packs. For a first attempt it may be possible to buy one secondhand, or even borrow one, of a known stated capacity, try it and work from there.
The fit of a backpack is every bit as personal as footwear and much more important than with small daypacks. Regardless of the quality or research that went into them, different designs and back-systems suit different people and the variation in the subjective feel of the packs can be huge. It is essential to load them up in the shop with a typical weight (and volume) and walk up and down stairs with several different makes and designs. Even then, it canít really be evaluated properly until youíve been carrying it for hours on the hill, but at least you can eliminate the clear losers and get one that feels basically right for you. For packs that have an adjustable back length, it is worthwhile to get the staff to adjust it for you to ensure that the load is transferred correctly to the hips with no undue pressure on the shoulders, if in doubt try several positions.
The very light packs usually have no back-length adjustment but come in several sizes, the chart at right shows the measurement of back-length to prepare for a fitting.
The material used in backpacks usually resists water well, but it will still penetrate at the seams in heavy or prolonged rain. Even standing the pack on wet grass can cause a surprising amount of upward seepage. Zips on external pockets sometimes have an overhanging flap to help protect them, the Golite Quest and LiteSpeed claim to have watertight zips. For the main pack compartment a liner is essential.
When considering the weights of items of gear, it is easy to forget the weight of any watertight bags used in the packing system. Until now we have used pack liners from Outdoor Designs made from Neoprene coated 210d nylon with taped seams and a fastex buckle closure. Although these liners are very tough we had never weighed them - and it was quite a shock when we did. The 70-80l one weighed 279g and the 50-60l weighed 190g.
We have now bought Sea To Summit pack liners made of UltraSil, a PU coated Siliconized Cordura. The 70l one is 98g and the 50l is 74g, a very good weight saving. These are intended for 'normal' backpacking use and are claimed to be watertight in the wet conditions encountered when walking, but the manufacturers stipulate that they are not guaranteed waterproof when submerged in water.
Tests carried out in May 2006 by Jim Wood conclude with a very negative view of UltraSil, and the article paints a quite alarming picture. The hydrostatic head is very low and the photos show leakage from the base when the bag is filled with water. However the theme of the article is the search for a bombproof solution for all conditions, even severe ones like immersion in river crossings, and we are not sure how well that test reflects a real life scenario where the bag of gear is enclosed inside a backpack and subjected to rain.
We will use these liners at least for short trips outside winter with a forecast of good weather, when the pack liner is just insurance and the consequences of any deficiency will not be serious. The search for a totally dependable lightweight pack liner will go on.
Bin bags are far too fragile and tear easily when stuffing things in. Even the bags advertised as 'garden refuse sacks', which are stronger, are not really strong enough. We found a fairly good solution in the early days: a cut-down survival bag. These are pretty tough and should last considerably longer. We put the bag in the pack and stuffed it full of gear, ensuring that it was snugly against the bottom and sides, then cut off the excess, leaving enough to fold over a couple of times.
If you adopt the cheaper plastic bag option, wrapping critical items like sleeping bags, especially down ones, individually for extra protection is good insurance. There are a few waterproof backpacks available but we have never tried them.
All but the most basic packs should have a padded back that maintains a hollow channel to allow airflow along the spine area, which helps to keep your back cooler and drier. It may be possible to 'mould' the shape of a thin ultralight pack after filling to create a channel. External mesh pockets are immensely useful while adding very little weight, and these days many have hip belt pockets. Some have elasticated bungee cords like our Kimm Run35.
Back systems are the subject of some debate, and pack development is driven by marketing forces like anything else, with manufacturers apparently trying to outdo each other with increasing sophistication. Minimalists argue that mainstream packs are becoming too complicated and generally have too many fixings, and they all tend to add weight. There are certainly quite a few on most packs, but the most effective systems in the long run tend to be the simplest.
The important straps are the front ones that draw the pack into the body and the side ones that cinch the load down tightly. The top straps (sometimes referred to as load-lifters) are also a valuable adjustment. For winter, an ice axe loop and small holding loop are required. Also important to us is the sternum strap, which may or may not be removable without cutting. Some people find them too constricting and remove them but we find them valuable for body-hugging stability, both in large packs and small daypacks - it's a personal choice.
There have been various developments recently in backpack design like the Berghaus Bioflex system and custom moulded shaping, but the latest Exodus range from Mountain Hardwear is something else: it has to be assembled and consists of a customisable Fit Lock system of Mini-frame (picture at left), pivoting waist belt, U-Bar shoulder harness, tube-system connection at the hips and a pulley system to adjust the torso length on the fly!. Looking more like a costume frame for a Star Wars stormtrooper, you have to decide whether very complex systems like these will truly be of benefit to you as a backpacker, or whether they were designed to appeal to gear freaks with more money than sense. Search your feelings!.