Backpacks for Arctic Trekking

We went down several design avenues when selecting the right pack for an expedition like this.

It all came down to what sort of pack would be most appropriate for a route and environment like this. So, let's start with key features of the route, and location/season, that might affect pack selection:

1. It's going to get wet. A pack that absorbed as little water as possible, and was as effective as possible, at keeping water out of the packbag, are desirable features. This is a wet environment. It rains a lot, we're camping on wet ground, and we have dozens of rivers to cross - some that require swimming. The pack needs to keep the contents dry.
2. It needs to carry weight. We're humping 50+ pounds of food, and a little bit of gear, at the beginning. The pack also needs to be "soft" enough so as not to inhibit mobility while moving fast with very light loads towards the end, for our highest mileage days.
3. It needs to adapt to variable load volumes. This criterion alone elimintaes most of the packs on the market, which are poorly compressible in large volumes and don't generally carry gear on the outside well in larger volumes. All the gear needs to fit inside the packbag (for river crossings), yet the packbag must be adaptable to a rapidly shrinking load volume as the trip progresses. In other words, a small load must also result in a small pack (in contrast to a small load carried poorly in a big pack) in order to maximize our efficiency and comfort for high mileage days and rapid pace towards the end.
4. It must provide immediate access to all essential gear used throughout the day without having to access the packbag. That means we need to be able to reach two liters of water and 2000 calories of food without taking off the pack, and being able to grab wind and rain gear without opening the packbag. The goal here is twofold: we don't want to waste time dealing with gear, and we don't want to expose gear inside the packbag to the elements unnecessarily.

This criteria led the development of custom "dry bag harness" packs by ULA Equipment, affectionately and informally denoted as the "ULA Arctic Dry Pack". The packs are based on a design by Roman Dial for Alaska trekking and packrafting, and implemented in various forms in the past by Dana Design and Cascade Designs, and since then, pretty much "upgraded" to a state of dysfunctionality in some form or another by these and other manufacturers (or in the case of Cascade Designs, discontinued altogether).

The ULA Arctic Dry Pack integrates two key components: a dry bag and a harness.

About the Dry Bag. We have selected the Pacific Outdoor Equipment 65L Pneumo Dry Bag (12 oz / 340 g) for our packbag. We tested so-called ultralight dry bags from other manufacturers, including Outdoor Research (seal not waterproof under immersion, outer fabric absorbed significant quantities of water) and Sea to Summit (neither seals nor seams waterproof under immersion, poorly durable fabric*). The POE Pneumo proved to be completely waterproof at its closure, seams, and fabric, even under significant immersion pressure. It also offered slots at the bottom of the bag through which compression straps could be threaded to cinch a heavy load into the lumbar region of the pack harness. Finally, it comes with an air exchange valve, which is a very nice feature for (1) compressing the packbag as much as possible while hiking for best load stability, and (2) inflating the packbag for river crossings to improve flotation and minimize the net pressure of water against the packbag fabric during immersion.

* The Sea-to-Summit Ultra-Sil Dry Sacks deserve a fair assessment here. First, they are not designed or intended to withstand the water pressures of immersion. They are intended to provide rain protection to gear while packed inside a backpack. Ryan will be using Ultra-Sil Dry Sacks inside his main POE pack dry bag for his sleeping bag, insulating clothing, and satellite phone electronics.

The image to the right shows the packbag in "inflated" mode when in the harness.

About the Pack Harness. The ULA Arctic Dry Pack offers the following features, and weighs 24-30 oz (depending on size and other options):

• Dry Bag Compression System. One outer harness, one top cinch strap, and three sets of side cinch straps for securing the dry bag to the pack harness (see image to right).
• Replaceable / Customizable Back Pad. Can be adjusted to accomodate variable types of padding and frame stay configurations. For example, Ryan's backpad is constructed of a dual density foam and twin frame stay sleeves for load transfer.
• Wide, but Thinly Padded Hip Belt & Shoulder Straps. To maximize surface area for load transfer without inhibiting movement or binding under heavy weight (see image below).
• Large Hip Belt Pockets. Each pocket can hold 1,000 or more calories of food (see image below).
• Rear Mesh Pocket. Rear mesh pocket has three openings (center and two sides). Side openings have elastic drawcord closures and are accessible while wearing the pack. Perfect for water bottles. The center opening can be used to stash clothing, more food, or trekking poles. (See image to right).
• Bear Spray Holster. Shoulder strap offers a bungee system for securing a can of bear spray.

Comments

[Erin McKittrick]

Hey Roman,

Neat to just use one of the orange drybags for the pack.

One thing I've always wondered though, about the "one-big-drybag" systems... What do you do if you get some stuff wet?

For example: tarps, outer clothing layers, rafts (though I know you don't have them this time), etc... are all things that get wet in the course of normal use.

Once they're wet, and you're stuffing them in the one drybag with the rest of your gear, how do you keep from getting the sleeping bag, dry clothing, etc... in there wet as well?

[Roman Dial]

Good question, Erin -- what I do is not put anything wet in the dry bag, ever. Wet stuff goes between the mesh and the dry bag or under the straps and over the dry bag. Raft goes on top, wet clothes outside. I am very meticulous about keeping stuff dry. We will likely use another little 15 L dry bag to put our sleep quilt/socks in inside the dry bag.

When packraftin' con bushwackin', inevitably the big outer dry bag gets damp inside and so I have an extra mini dry bag inside for the sleep gear.

Sometimes I look like a walking yard sale with crap all hanging out to dry, but the straps and mesh make it convenient. But wet stuff is heavy stuff and by hanging it out to drain and dry I can lighten my load.

Roman

[Tony]

Seems odd to put 4+# of water 8+" from your back. Why not have side bottle holders? Though, I'm not sure you ever need to carry 2L on your trip. Maybe you plan to hang bottles from your shoulderstraps? And you placed bottles in the photo to display the pockets, not to show a particular load configuration?

[Roman]

Yes, Tony, that would be an awkward load. The photo was demonstrating that water could be put on either side (or both). That being said, most all of us have had to "hang", so to speak, a liter off the back of our pack at one time or another, even though side placement is much more efficient.

On most trips in Alaska (which is where 90% of my experience is, hence my quirky traveling style), water is everywhere. I rarely carry it farther than the distance from creek to camp, preferring instead to keep my water bottle handy (as in the photo) but empty. Then I gulp up to 3/4 or a full liter at a creek when convenient or thirsty.

Now, on this particular trip where we will spend full days hiking long, dry ridges, I will have to carry water. In this case, I will likely have up to two liters strapped high on the pack (maybe inside, maybe outside of the dry bag, depending on leakage and condensation) and a third liter handy (but, yes, heavy with torque) in the pocket as seem in the photo.

The original design requirements suggested a series of three pockets that wrapped all the way around the pack, simialr to Saloman adventure racing packs, but that didn't make the final design.

Roman

[Tim Mayne]

You guys are nuts!

Do your wives know what you're up to?!

Good luck. I look forward to following your progress.

(Roman's ex-brother in law. Or did you make an honest woman out of her again?)

[Bill Fornshell]

Your pick of the Pneumo Dry Bag was a good one. I have two of the same type bags you are using. I have the 50L and the 15L. The bags work really nice - except - the listed weight on both of mine are 24.5 grams and 23.5 grams HEAVIER than listed. With an ounce being 28.35 grams this makes both bags almost 1 ounce over the listed weight.

I don't agree much with the pack design. It looks like something that stopped at the "first draft" stage and with a little more real thought might have been turned into a real good idea. It seems to put all your "eggs" in one basket. A larger mesh pocket across the back and maybe on the sides would have given you a place for the things that get wet. I understand a goal of having everything inside the bag. Do you just asumed that everything will get wet and that your body heat might dry things during the day or at night? Seems a larger risk than necessary.

Maybe things will change between now and the 11th.

[Gil Aegerter]

It's been interesting watching the debate at various forums over gear choices and philosophy. A couple of questions: Did you hold back on the amount of mesh to reduce snagging? And about the intersection between harness/"frame" and the dry bag: Are the side straps the only things connecting the dry bag to the harness or is there other support that's not visible?

I'm so looking forward to your posts from the field. Good luck!

[Gil Aegerter]

Never mind on the second question. Now I see that the mesh bag is part of a tongue that wraps up from the harness. Seems like a good idea. Any issues of chafe on the bag?

[Roman Dial]

I, too, would like the mesh to be a full wrap -- the woman who makes the Alpacka Raft, Sheri Tingey, has a really cool full mesh design that I have longed after for years (she's made several for her family); however, the design pictured above is a bit lighter.

As for snagging, the Brooks Range to my experience is the best wilderness travel in the world because there is so little brush. Bushwacking is almost a misnomer there, as we rarely have to whack any more than thin (as in density, not necessarily diameter) willows along rivers and creeks. We will only pass through spruce (and again these will be thin) at the end -- assuming we get past the 500 mile mark.

Backpacks, shoes & socks, and underwear bottoms are the most crucial pieces of gear for travel that's long and fast. Blisters, chafing, and a painful load are what result for me from wrong choices in those departments. So the shoes, socks, and pack I am using are updated versions of what I have found to be comfortable for me in the past. Nevertheless I have not tried that many backpacks, shoes or socks, so I am not as experienced in gear varieties as Ryan or probably you for instance.

I tend to find something that I like and keep using it -- I am very conservative that way!

[John Pugh]

Excellent choice on the drybag. We used Pacific Outdoor Equiptment drybags on our 2,150 mile canoe trip down the Mississippi River last summer. Zero problems, zero leakage.

We use a similar system to yours when backpacking using 2 homemade packs. Simplicity in motion is the only way to go.

-John Pugh

[Brian]

I've had a number of queries in regard to the availability of the ULA Artic Dry Pack and its potential as a future ULA product. At this point I am considering doing a small manufacturing run of the pack as a 'special edition' to get packs to those folks that are interested. If you are, please feel free to e-mail me and I will get your name on the list and keep you posted. Thanks!

[david cheatham]

cool pack would like info on that harness system and actually the full pack..thanks dave

[Joseph DaLuz]

Sorry if this is a redundant question, but has ULA made plans for making a production run on the pack harness/drybag system yet? I couldn't find any information on their site regarding this.

[Ralph Netta]

I'd be very interested in buying one of your ULA Artic Dry Packs

[Steve]

Looks very cool - is there a way to retrofit my granitegear with those mesh hip pockets?