Recently I had to look through photos of the Great Western Loop from 2007. My, my, I had such a small and light pack. But the trend has been moving in the wrong direction ever since, and for about a year I’ve been using a pack that has more volume and weighs more than anything I’ve used since 2002, when I started the Appalachian Trail as a noob with a Mountainsmith Frostfire 4500.
I have now used the Osprey Aether Pro 70 for about 50 days, including on most of my guided trips for the past year, a spousal trip to Utah’s Cedar Mesa, an elk hunting trip in the Colorado Rockies in November, and weighted training hikes in Boulder’s foothills.
For women, Osprey offers the Ariel Pro 65, which has identical features and materials, but a women-specific fit and five liters less capacity. Nearly all of my comments about the Aether are applicable to the Ariel as well.
Long-term review: Osprey Aether Pro 70 and Ariel Pro 65
The Osprey Aether/Ariel Pro will appeal most to backpackers who:
- Must carry large or heavy loads that exceed the volume or load-carrying capacity of modern lightweight packs; but,
- Want this performance from a pack that weighs 3 to 4 pounds, rather than the normal 5 to 7 pounds.
When I’m leading clients, hauling out elk quarters, or carrying most/all of the food and gear on a group trip, the Aether Pro has become my go-to. I think Osprey also imagined it being used for alpine/mountaineering expeditions and for adventurous long-distance hikes (e.g. thru-hiking the Brooks Range).
My sole criticism of the Aether/Ariel Pro is its external storage. Instead of the removable compartments located in the “wedge” between the hipbelt and main compartment, I’d rather have conventional side pockets and hipbelt pockets, plus a shoulder strap pocket. But I’ve overlooked this shortcoming because of its performance otherwise.
- Volume: 70 liters (4272 cubic inches) in size Medium
- Strong and durable fabrics throughout
- Stiff aluminum peripheral frame and a single aluminum center stay
- Mesh-covered aerated foam back panel
- Heat-moldable foam hipbelt
- Two front compression/attachment straps
- Attachment points for trekking poles, two ice tools, hydration reservoir, and sleeping pad
- $375 MSRP
- More information (men’s, women’s)
The spec weight of the Aether Pro (in size Medium) is 3.94 pounds (3 lbs 15 oz, 1.79 kg). My pack is over-spec by 2.9 oz; it weighs 4 lbs 1.9 oz (1.87 kg). Its weight can be further reduced by removing features:
- Floating top lid (5.1 oz)
- Two side compression straps (0.5 oz each, or 1.0 oz total)
- Zippered side pocket (2.7 oz)
- Cinch-able side pocket (2.6 oz)
The total weight of these removable items is 11.4 oz, which would reduce the spec pack weight to 3 lbs 3.6 oz, but at the cost of some functionality.
To help you decide if the Aether/Ariel Pro is right for you, comparing it to other packs is probably useful.
Aether Pro vs Aether AG
The Aether/Ariel Pro was new for spring 2018, and Osprey kindly sent me it and two other packs that it had updated or launched that season, the Exos and Levity. The Pro is essentially a stripped down version of the Aether AG (“Anti-Gravity”).
Compared to the AG, the Pro:
- Uses more premium fabrics;
- Has a simpler harness system that’s lighter and probably carries better, but less ventilated;
- Is 1.3 pounds lighter, with an opportunity to shed extra weight by removing features; and,
- Costs $65 more, $375 vs $310 for the 70-liter versions.
The only thing I wish the Pro had is the AG’s external pockets.
Aether Pro vs “sweet spot” packs
My pack recommendation for most backpackers is a 2.5-pound framed pack that is nicely featured, made of durable materials, and costs $200-$300 such as the Osprey Exos, Sierra Designs Flex Capacitor, and ULA Circuit.
Such models are ideal for standard thru-hikes and high routes, and for backcountry trips up to 7 or 10 days. If your plans are more exceptional and require a pack with more volume or greater load carrying capabilities, plus some additional durability, the Aether/Ariel is worth a look.
Aether Pro vs. Deuter, Gregory, and Mystery Ranch
Other packs match (and may exceed) the volume and load-carrying capacity of the Aether Pro, including the Gregory Denali 75, Deuter Aircontact 65 + 10, and Mystery Ranch Glacier. But none of them rival its sub-4 pound weight. In size Medium, the Denali weighs 6 lbs 3 oz; the Aircontact, 5 lbs 6 oz; the Glacier, 5 lbs 10 oz.
Aether Pro vs Seek Outside Divide and Unaweep
The most direct comparisons to the Osprey Aether/Ariel Pro may come from the backpack hunting industry, which is presented with similar volume/load demands. I’m specifically thinking of the Divide 4500 and Unaweep 4800 from Seek Outside. Both packs weigh in the low- to mid-3 pounds and approach $400.
Suspension + harness
The standout feature of the Aether/Ariel is its suspension. Simply put, this pack is designed to haul weight. It’s light-years better than the Exos, and even in a different league than the Flex Capacitor, which is considered to carry weight better than most (all?) sub-3 pound packs.
The peripheral frame made of 7075 tubular aluminum is extremely stiff, so it efficiently transfers weight. As I’ve come to expect of Osprey, the harness system is masterfully fitted, and the weight is distributed well across the hipbelt, shoulder straps, and back pancel, which have generous but firm cushioning.
On overnight trips I regularly have carried loads in the low-40’s, and on recent training hikes I’ve carried exactly 50 pounds (courtesy of two 12″ x 12″ concrete stepping stones wrapped in old towels, plus some other gear for filler). I will never say that carrying 50 pounds is comfortable, but some packs do it more gracefully than others, and the Aether/Ariel is among them.
To achieve this load-carrying performance in a sub-4 pound pack, Osprey gave the Aether Pro a more conventional back panel, abandoning the ventilated trampoline that you’ll find on the Exos and Aether AG. The mesh-covered aerated foam (branded as AirScape) provides relatively little ventilation in reality, so you should expect perspiration to buildup on warm days and during hard efforts.
The Aether Pro is spec’d with four types of fabrics:
- Main body: 210d nylon x 200d UHMWPE
- Bottom: 200d UHMWPE
- Accent: 315hd oxford
- Trim: not specified, but appears to be a 200d-ish nylon
UHMWPE stands for ultra-high-molecular-weight polyethylene, and is the source material for Dyneema and Spectra fibers. Presumably as a cost-savings measure, Osprey chose non-branded UHMWPE fabrics. Sierra Designs made the same decision with the Flex Capacitor, and internally we referred referred to the fabric as “Chineema.” Osprey has branded the body fabric as NanoFly.
The bottom fabric is a pure UHMWPE.
While writing this review I inspected my pack for wear, and found no abrasions or tears. The Aether/Ariel seems like it’s built for a lifetime of use. If this proves not the case, it’s covered under Osprey’s All Mighty Guarantee.
The main compartment is tall and narrow, even before the extension collar is utilized. I believe this shape leads to better load stability, but it’s disappointing that a full-sized bear canister (e.g. BV500) cannot be stored horizontally in the Aether. Shelters and hammocks without intentionally short pole sets will have to be placed vertically, too.
The floating top lid is nicely sized, and is convenient storage for items that you occasionally need during the day, such as toiletries, snacks, extra water storage, and even a windshirt or minimalist rain jacket. If you don’t need its volume or wish to pare 5 oz from the Aether, it can be easily removed.
The hipbelt/side pockets are underwhelming, and I consider them to be the Aether’s most notable imperfection. I believe it’s essential to have quick access to oft-needed items like water, a camera or phone, maps, skin treatments (e.g. lip balm, sunscreen, insect repellent), a headnet, water purification and other items. The design of hipbelt pockets and side pockets is vitally important — they must be accessible, secure, and generous.
To their credit, the hipbelt/side pockets are easily accessible, and one can be zippered shut. But their total volume is marginally acceptable, and the cinch-able pocket is deep enough only for a 1-liter Nalgene. Using a 1-liter Smartwater bottle (which weighs 2.4 oz less) is impractical — it immediately slips out if you lean forward, like to pick up a trekking pole or step under a downed tree.
I appreciate that Osprey tried something different here, but personally I would have preferred the Aether AG design, which includes two permanent side pockets and two permanent hipbelt pockets.
Compression and utility
The Aether/Ariel Pro has two sets of compression straps:
- Two horizontal straps across the front, and
- One Z-style removable strap on each side
In addition to stabilizing the load, these straps are useful for securing trekking poles, an umbrella, ice tools, and long tent poles. I have not tried, but I’m certain that snowshoes would fit perfectly on the front. Skis could be attached, too, but I’d want to protect the pack fabric from the metal edges first.
The side compression straps photograph well, but the webbing does not slide easily through the rectangular sliders. O-rings would have been a better choice.
Questions about the Aether/Ariel Pro 70, or have an experience with it? Leave a comment.
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