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Reviews > Shelters > Hammocks > Hennessy Explorer Ultralite A-Sym > Test Report by Bill Jeffrey

September 30, 2008



NAME: Bill Jeffrey
EMAIL: wjj2001 AT yahoo DOT com
AGE: 50
LOCATION: San Diego County, California, USA
HEIGHT: 6' 4" (1.93 m)
WEIGHT: 230 lb (104.00 kg)

I have over 30 years backpacking experience. I try to get out once or twice a month, plus at least one week-long trek each year, including a section of the Pacific Crest Trail. Terrain varies from sea level to 14,000 feet (4,300 m), desert to mountain, and trail to cross country, occasionally including snow travel. My hiking style tends towards lightweight but not quite ultralight.



Manufacturer: Hennessy Hammocks
Year of Manufacture: 2008
Manufacturer's Website:
MSRP: US$219.95
Listed Weight: 2 lb.7oz. (1092g)
Measured Weight: 2 lb. 7.6 oz (1122 g), including a pair of SnakeSkins

Weight of components:
Hammock 22.1 oz. (629 g)
Rain fly 11.6 oz. (330 g)
Tree huggers 2.8 oz. (80 g)
SnakeSkins 2.0 oz. (58 g)
Stuff sack 0.8 oz. (25 g)
Note: Total measured weight differs from sum of component weights because of rounding of fractional ounces.

Hammock, fly, tree huggers, & Snakeskins
Specifications (all per manufacturer website except as noted):

Weight limit: 250 lbs (110 kg)
Suspension system:10 (3.05 m) long 1600 lb. (726 kg) test polyester ropes with
1.5" (3.81 cm) wide by 42" (107 cm) long nylon webbing straps called "tree huggers"
Measured suspension system: 8.5' (2.59 m) long ropes, including the connection to the hammock
Hammock dimensions: 108"' x 48" (274 cm x 122 cm)
Measured hammock dimensions agree with specifications, when measured laying on a flat surface. Width measurement is perpendicular to the ridgeline.
Hammock fabric: 70 D nylon taffeta, 160 x 90 high count
Rain fly dimensions: - a parallelogram with
- long side = 120" (305 cm) - measured 110" (279 cm)
- short side = 70" (178 cm) - measured 70" (178 cm)
- long diagonal = 140" (356 cm) - measured 140 " (356 cm)
- short diagonal = 128" (325 cm) - measured 126" (320 cm)
Rain fly fabric: 1.1 oz. (32 g) 30 D Silicone nylon
Mesh: 1 oz. (28 g) 20 D polyester No-See-Um netting
Stuff sack: Logo and set up instructions printed on ripstop nylon bag
Set-up-time: 3 minutes
Packed size: 5" x 12" (12.7 cm x 30.5 cm)
Measured stuff sack size: 13" x 10.5" (33 cm x 26.7 cm), measured flat
Colors: "Coyote brown" hammock and fly


The hammock arrived by mail on May 15, 2008. Inside the soft plastic mailing bag was a stuff sack containing the hammock, fly, and tree huggers. Also included was a pair of SnakeSkins, which are two long tubes that serve as a specialized stuff sack for the hammock intended to make set-up and break-down easier. The MSRP of the SnakeSkins is $19.95, but they were included with the hammock as a limited time "spring special." The SnakeSkins weighed in at 2.0 ounces (58 g), as compared with 0.8 ounce (25 g) for the included stuff sack.

Not included with the hammock but required for set-up are two tent stakes.

The hammock appears exactly as described on the manufacturer's website. That website itself is, in my opinion, rather busy, making it fun to browse through but often leaving me wondering if I've found everything available on what I was looking for. I also noted that the specifications for this product differed somewhat between the page describing this specific hammock and a separate page comparing all their hammocks. I have used the former for purposes of this report.

A look over all the components revealed quality construction, no snags, no loose threads. That's good, since it needs to keep me from falling out of the trees.

A little about where I'm coming from:

I have talked with Tom Hennessy in the past about hammocks at trail events, climbing inside to marvel at their wonders, but always giving Tom several excuses of why hammocks wouldn't work for me. Every time I thought about going to a hammock, I talked myself out of it. As I have progressed up the Pacific Crest Trail into northern California (where I will be hiking this summer), I find there are often plenty of trees but little good level ground to pitch a tent where I want to collapse for the night. This test will give me an opportunity to become an Ewok and not worry about camping on the side of a hill. Therefore, my review is as a person who is hesitant about hammock camping.

Hammock Description:

The bottom of the hammock itself is made of 70 D nylon taffeta. It appears to have some water repellency to it, although it is breathable. The color is "Coyote brown," which blends in well to many tree trunks for low visual impact. Now, how do I describe the shape of the floor? Take a diamond, then move one corner on the long side half way to one end, and the corner on the other long side half way to the other end. That's the A-sym in the name, as in asymmetrical. When sleeping on my back, my left shoulder is in one a-sym corner and my right knee in the other. This has me sleeping about 10 degrees off the main axis of the hammock, resulting in a virtually flat sleeping surface instead of sleeping on the curve of the hanging hammock.

At each end of the hammock the fabric is remarkably neatly gathered together and affixed to a rope by means of knots hidden beneath a small black nylon sheath.

On each side, at the previously mentioned a-sym corners, is a plastic ring, to which is tied a length of shock cord. These are used to guy the hammock body out, both expanding the width of the interior of the hammock and dampening swaying.

The entrance to the hammock is Hennessy's patented "Easy Enter" through the bottom. At the foot end of the hammock is an opening, 54 inches (137 cm) long, closed with a hook-and-loop fastener. This is Hennessy's "Snap Tight" closure, designed to close automatically (using your body weight) after you enter.

The upper part of the hammock is all mesh for ventilation. Also passing through the top of the hammock, attached only to the ropes at the ends, is a smaller ridge line. The body of the hammock hangs from this ridge line, so that the bottom of the hammock is not under the same high tension as the ropes. This also allows for a flatter sleeping surface.

Since almost anything put on the floor of an occupied hammock will slide towards the person on the hammock, gear storage in the Hennessy is accomplished by several simple but convenient attachments to the ridge line. A mesh pocket 21 inches (53 cm) long at the top and about 8 inches (20 cm) deep its deepest, slides along the ridge line so it can be placed where most convenient. It is separated into three compartments, one large enough for pretty much all the odds and ends I'll need at night, as well as the contents of my pockets, and the other two much smaller and convenient for keeping handy those things I might need during the night or first thing in the morning, such as contact lenses and lip ointment.

Also attached to the ridgeline are two small hooks to clip a flashlight or other item to. At the far ends of the ridge, deep in the corners, the ridge line forms a small loop to which a small carabiner could be clipped to store heavier items such as day packs and water bottles so they don't slide to the middle where they would be in the way. Finally, some items, such as books and eyeglasses, can simply be draped over the ridge line when done reading in bed.

Rain Fly:

The entire hammock can be covered with a waterproof silnylon rain fly. The fly is cut with a catenary curve to maintain tautness.

On each rope on the hammock there is a Prusik hitch to which is attached a hook. Attached to all four corners of the fly are both a ring and a hook. The two corners on the shorter diagonal also have lengths of thin braided cord for use as guy lines. The two corners without lines are fastened to the hammock by putting the ring on the fly's corner on the hook on the hammock's rope, and by clipping the hook on the fly to the hammock's rope itself. The Prusik hitch is a sliding knot that allows the fly to be adjusted tautly.

Because the hammock is entered from the bottom, there is no need for any entrance on the fly itself.

Tree huggers:

Lengths of 1.5-inch (3.81 cm) wide, flat nylon webbing, with loops sewn on each end, are provided. These are wrapped around the trees to protect the bark of the trees and to help keep the rope from slipping down the tree. The tree huggers provided are 46 inches (117 cm) long. Three sizes are available as accessories, 42-inch (107 cm) (presumably the size included, and intended for trees up to 15 inches (38 cm) in diameter), 72-inch (183 cm), and 96-inch (244 cm). More on their use later.


SnakeSkins, normally an optional accessory, were included as a spring promotion. They are long tapered silnylon tubes looking like, well, snake skins. Intended to be installed once on the hammock's ropes and then left in place, they taper from 3 inches (7.6 cm) at the widest to the width of a finger at the far end. Once the hammock's ropes are passed through, they can be pulled over the rolled hammock to keep it clean and dry during set-up and break-down.


Instructions printed on stuff sack

The instructions for the hammock are printed on the stuff sack as shown in the photograph. Being new to hammocks, I first set up the hammock following only these instructions.

My first task was to find two suitable trees the appropriate distance apart. While not specified in the instructions, I recalled reading somewhere, perhaps their website, that this distance was 12 to 25 feet (3.7 to 7.6 m). While I have a number of trees on my property, they are either fruit trees with many branches blocking the trunk, or single shade trees without partners nearby. I finally located one pine tree and an acacia with a large branch just over the minimum distance. This would be my initial set-up location.

The instructions say to wrap the webbing straps (tree huggers) one or more times around the tree. Already I am hesitant, as I am unsure if simply passing the strap around the tree and gathering the two ends together constitutes "one time around," or if I need to have the straps pass over each other once (which might actually be called twice around). Since my trees were not too big, I elected to go twice around, and although the loops on the ends of the straps were a bit farther apart than I thought they should be, I was able to pass the rope through the loops and tie them off.

The recommended knot for tying the ropes to the webbing is not given a name, but called either a lashing (but not saying what kind of lashing, and I think of lashings as used to tie logs together to build signal towers and monkey bridges in Scouts), or a "figure 8 pattern." The line drawing on the stuff sack was of little help. Finding on the hang tag attached to the stuff sack a final line, "For more useful tips to stay warm and dry, check our web site," I went and found a photograph and then a video of the lashing. Still a bit uncertain, I was successful the first time. The video was the most helpful, but if the scene had been shot from above rather than the side I think it would have been more clear. Still, mission accomplished.

Tying one side off, I moved to the other and tied it, then went back to the first to tighten it up. Oops, too low. I learned the hammock should be tied at about the top of my head. Trying again, much better.

Now, what to do with the side cords? The instructions just mention adjusting the width by "changing tension or angle of side cords to tree branches, bushes, rocks, improved stakes or to canopy side adjustment cords." I think they mean by tying to these things, although since the fly hasn't been pitched yet that won't work. I tied it off to some branches, although I kept wondering if I should pull it perpendicular to the ridge, or angled front and back, and if it should be pulled down as well as out.

Climbing in, I was so pleased with my efforts and immediately so comfortable, I had to resist the temptation to take a nap right then, and instead continued with pitching the rain fly.

First, the instructions say to align the asymmetrical fly to match the hammock shape. I figured this out fairly easily, but it would have been helpful to know up front that the corners with the lines attached were the sides, and the other corners the front and back. Clipping the O-rings to the hooks on the Prusik and the hooks to the hammock ropes was easy. Then I had the same dilemma as before - where do the side guy lines go? The instruction's "whatever angle seems right for the conditions" didn't help much as I pondered how much of the hammock I had to cover if it really did rain. Since it wasn't raining and I wasn't spending the night out tonight, I just tied them to some bushes.

It all worked out fine, maybe even great, but given my unfamiliarity with hammocks, I would have appreciated some step-by-step directions, especially on the guy lines, which I didn't find even on their web site.


Hennessy Hammock

Ok, it's all up. It doesn't look too shabby for my first attempt, even pretty cool. Back inside. The bottom entrance is very simple: open it, turn around and sit down, and lay back and put your feet up. I can handle that. Laying back and feeling the fabric stretch gave me the same feeling of trepidation I had when I did my first repel off a real rock - will it hold me? Of course it did, and I enjoyed just hanging out in the trees. Moving around, I was impressed with how stable this hammock was, and never felt like I would flip it over, even though I hadn't really tied the side lines securely. I think I'll get used to this real quick. All too soon, it's time to go inside.


I am planning a week-long hike on the Pacific Crest Trail in Northern California in late June or early July. Elevations will range to 7,500 feet (2,300 meters). Temperatures 30 to 90 degrees (-1 to +32 C) with a chance of rain. Shorter trips will be in the mountains of Southern California, elevation 1,200 to 10,000 feet (300 to 3,000 meters). Temperatures 15 to 85 degrees F (-10 to +29 C) with a possibility of rain.


Specific items to be tested include:

  • Set up: time, ease, tension, tie-outs, and if weather permits pitching in the rain.
  • Pack-up, using SnakeSkins: time, ease, and fuss.
  • Pitching options where trees are not present, suspended from the trunks of large shrubs, or over a ravine as conditions allow. I will also use it one night on the ground as a tent (Tom says it can be done) as a test of its ability to provide shelter above timberline.
  • Stability: during tossing and turning, effects of wind.
  • Comfort: back support, fabric noise.
  • Padding: for both insulation from cold air under the hammock and for practical considerations (lay flat, bunching up, sliding out) in the hammock.
  • Ease of entrance and exit.
  • Room: for self and gear.
  • Waterproofness: fly coverage, and water running down the ropes.
  • Ventilation: condensation, including at the far ends of the hammock.
  • Temperature build up inside.
  • Wind blockage by mesh or need to lower fly.
  • Durability: testing the hammock near its stated weight limit, seam stretching or tearing, rope and tree huggers stretching or fraying, tree huggers, damage from branches.
  • Dual purpose: use as camp chair and kitchen shelter during rain.
  • Bug-proofness: of mesh and fabric, ease of entrance to minimize bugs getting in.


So far, I'm impressed. But, the real test is living in the trees. I've already been there one night, but that's for the next report. Stay tuned.

This concludes my Initial Report. The Field Report will be amended to this report in approximately two months from the date of this report. Please check back then for further information.



The field test was conducted during two trips:

1. An overnighter on Mount San Jacinto in Southern California in a forest at 7,700 feet ( 2,300 m). Temperature ranged from a high of 65 degrees F (18 C) to a low of 43 F (6 C) , with moderate winds, no moisture, and light mosquitoes.

2. A four-day, three-night trip on the Pacific Crest Trail in and near Lassen Volcanic National Park in Northern California, camp elevations between 4,500 and 5,500 feet (1,400 and 1,700 m), low temperature 53 F (12 C), light mosquitoes. Because of numerous wildfires burning nearby, I camped in developed campgrounds each night for safety.


Hammock in the trees.
Hammock in the trees. The Tree Hugger would not wrap completely around the larger tree on the right, requiring some of the hammock's rope to make up the difference and putting the hammock closer to that tree. The tie off to the left tree is the preferred arrangement, and the rope passed between the dead branches without causing harm to the hammock.


My first night on the mountain with the hammock had me setting up just before dark. Finding a nice spot with two trees the correct distance apart was easy. What I had not counted on was the nuances of having one tree about two feet (0.7 m) in circumference and the other 8 feet (2.7 m). The tree hugger went easily around the smaller tree. Moving to the larger tree, I could not reach my arms fully around it. I found two methods that worked - swinging the strap quickly so I could catch it with my other hand, or roughly hooking it on the rough bark of the tree. I would find one or the other would suffice on my next trip.

Another nuance is that using a larger tree at one end means the hammock is not centered laterally between the two trees, but is closer to the larger tree. As the hammock and ropes sag between the two attachment points when loaded (with me), if the hammock is attached to each tree at the same distance from the ground as the other, the hammock will slope up to the higher tree. Some finagling back and forth to lower one end and raise the other shortly got everything level.

On my second trip the 100 miles of trail I had originally planned to hike was closed because of several forest fires caused by lightning. Plan B was to hike fifty miles of trail just north of the closure. As smoke filled the valleys, and the weather forecast included the possibility of additional lightning strikes, I camped at the car campgrounds the trail crossed every 10 to 20 miles, in order to stay informed on fire and weather conditions. As I was therefore assigned to a designated campsite, I had to pick from the trees available in my site. Again, I usually found that the ideal location included one large old tree and one thin young tree. My practice on my first trip paid off, and by night three I was pretty quick at figuring out how high to tie off to the thin tree and how much lower to go on the larger tree. I had also learned the figure-eight lashing, and was doing it almost without thinking about it. Once I had identified the best pair of trees (which sometimes did take some time in my over-analytical way), I found I could hang the hammock faster than I could pitch a tent, and I didn't have to mess with clearing the ground of branches, rocks, and pine cones.

I tied taut line hitches in the elastic side cords to make them easier to adjust. However, it seems every night I had the lines going in different directions, sometimes perpendicular to the ridgeline, sometimes pulling a little more towards each end. Maybe this is a matter of how much sag I left in the ridgeline. Either way, it didn't seem to matter too much, although my second night in the hammock the sag did seem more pronounced and nothing seemed quite right.

I have not yet had the pleasure of hanging out in the trees in a rain shower. In my opinion, however, the rain fly is just big enough to cover the hammock body. If one end of the hammock is tied very close to the tree, as is the case if the tree is very large in diameter, there is not a lot of room left on the line to pull the rainfly tight on the ridge. This leaves a bit of hammock exposed. I did find I could disconnect the fly's hook on that end and attached it to the cord going around the tree and that would improve the coverage.

Tree Hugger and lashing.
Tree Hugger and lashing. The provided Tree Hugger fit nicely around this tree. The lashing is visible at the lower right, along with the end of the SnakeSkin.

SnakeSkins. Note tie off to larger tree.
SnakeSkins. Note tie off to larger tree requires using the hammock rope to reach the rest of the way around the tree. The SnakeSkins completely cover the hammock in this picture.


The SnakeSkins make it very easy to pack up and hit the trail. Once they have been installed on the hammock's ropes, they are left there. When time to pack up, I just slide the SnakeSkins to over the hammock, tucking the side guy lines up into the body of the hammock as I do so. Provided the hammock has sufficient tension on the ridgeline, this is an easy process, with sometimes just a tiny amount of work to get the last of the "bulge" of the hammock into the Skins. On the other hand, it is very difficult if the hammock has been taken down from the trees. Leaving the hammock tied to the trees until the SnakeSkins are fully in place is the key to easy packing. Once the hammock is covered, I untie the hammock from one tree and form large coils as I walk to the other tree and untie that side. The hammock never touches the ground. I then wrap the ropes around the bundle, ending up with a rather compact, although rather homely, package.

The SnakeSkins also make pitching the hammock very easy. Tying one rope to the tree (using the web strap), I then walk to the other tree, paying out the SnakeSkin-encased hammock as I go. After tying off to the other tree, the SnakeSkins slides easily to the end and the hammock is ready to be guyed and occupied.


I was surprised by how often the two perfect trees for my hammock had something growing between them, whether a shrub or a smaller tree. Either way, this sort of location would not make entering the hammock easy. Finding a spot with clear ground between the two trees, entrance is very simple - sit down, lie back, and pull my feet up. I have gotten over the nervousness I first had when I realized how much the hammock stretched as I lie down, although I have had several others watch and be amazed and impressed I didn't bring the whole thing crashing down.

Exit is likewise easy. Lying on the back, the feet should be to the right of the slit opening. By moving a foot to the left of the opening, a slight push down and towards the slit parts the hook-and-loop closure and I stand up and am out. I only had difficulty one night, the night I had apparently left a little too much sag in the hammock. It was a restless night, and I took several moonlit nature walks. Once I had difficulty getting the entrance open, but several times I found the slit had partially opened while asleep. However, I only had this happen one night, and I attribute it to a sloppy pitch.

Self portrait in the hammock.
Self-portrait in the hammock. The flash reflection on the mesh is not normally visible, although it is difficult to see through the mesh if a light is on in the hammock.

Lying back in the Hennessy Hammock is like lying back on a cloud. It's not unusually for me to fall asleep after a long day's hike, but this hammock is so comfortable I found myself napping one day when I had my miles done by lunch time.

It was easy to turn to sleep on my side or back. Trying to sleep on my stomach was not as relaxing, as it seemed to produce a convex curve in the hammock that didn't exist when sleeping on my side or back. In any event, with my body cradled by the hammock, I found myself more often sleeping on my back than my usual side or fetal position. The fabric wrapped around me so comfortably it was almost like laying back against a large body pillow. While I often have back pain after sleeping on the ground, I was very rested after sleeping in the hammock.

In spite of being surrounded by nylon hanging from the trees, I noticed the hammock was quite silent, with little sound coming from the fabric, even during moderate winds.


With my previous hammock experience being limited to mesh hammocks hung from a stand in a backyard, I was impressed with how stable the Hennessy generally was. Entering the hammock from the bottom no doubt is responsible for high initial stability, as my weight is initially center directed along the center line. The two side guy lines, made of thin elastic cords, don't hold the hammock rigid like a tent staked on the ground, but take the slight sways out and define the floor of the hammock. Tossing and turning generally resulted in just a little hammock movement, which quickly settled back to a calm stillness. More vigorous tossing, almost to the level of bouncing on a trampoline on one's back, moved the hammock quite a bit more, with no apparent harm to the hammock, and, again, it settled very quickly. Moderate winds, sufficient to blow the needles off the pines and stir up some dust, made pitching the hammock a little more interesting one night, but once I weighed it down (with myself) there was little swaying. Changing clothes is another matter, as I'll discuss shortly.


As nights were dry, I did not experience any condensation in the hammock, even at the far, narrow ends. As the entire top surface of the hammock body is mesh, there is probably enough ventilation to minimize any condensation, although I was unable to test this. About half the time I ended up with the rainfly pitched very low to the mesh roof. Still, in the dry conditions I had no condensation.

Being summer, even in the mountains, I found myself a little warm when first retiring for the night, even when laying on top of my pad and sleeping bag. The cocoon shape of the hammock caused the sleeping bag to wrap around my sides rather than lay flat as in the floor of a tent. Conversely, as the night cooled this kept me better covered when using my sleeping bag as a quilt.

The rainfly comes down the sides of the hammock to just below the level of the mesh. Even on the breezy night, the mesh stopped most of the wind that worked its way under the fly.


I had expected lots of mosquitoes, given that the snow had just cleared from the trail a couple weeks prior to my hike. Fortunately, mosquitoes were light, but there were some young ones out looking for first blood. Getting in and out of the hammock takes no more time than a tent, and perhaps even a little less since there is no door to zip open and closed. In any event, I got in without bringing any bloodsuckers with me, and while I could see them flying around the mesh, I never got bit, and that without using repellent. The hammock appears bug proof. If I had any risk of being bitten where my body was in contact with the bottom of the hammock, that risk was removed by sleeping on a pad (see below).
Hammock under its rainfly.
Hammock under its rainfly. Entrance slit is slightly open here.


In spite of predictions, I had no rain on my outings this summer, so have not been able to evaluate the waterproofness of the hammock and fly.


In spites of testing the hammock near its stated weight limit, I have found no stretched or torn seams, no stretched or fraying tree huggers, no abrasion of the fabric, or any other damage. These hammocks are clearly made with pride.


If the weather is pleasant, and the summer night is warm, there is no need to use a sleeping pad in the hammock. In my case, however, I got cold every night, and therefore used one of three different pads in the hammock. Reasoning I needed only insulation and not padding, the first pad I tried was a 1/8-inch (3 mm) ThinLight closed cell pad. Because this pad is so thin, it bunched up under me as I moved in the night, and I woke up cold. My next trip I used a short Thermarest ProLite 3 pad (1-inch / 2.5 cm thick). I expected that it's more rigid shape would not only stay put but, placed obliquely in the side pullout corners, would provide more shape to the floor of the hammock. Instead, the pad kept sliding out from under me. Having heard that others have used them in a hammock, I also carried a roll-up automotive windshield shade. This worked better than the other two pads, but still bunched and ultimately slid out from under me. Finally, my last night, I put the windshield shade inside my sleeping bag. While it still bunched up a little, it was not able to get out from under me. I do toss and turn much more than most people, and am still looking for the best solution. This, for me, is the biggest problem of sleeping in the hammock.


In a tent I can just toss anything and everything I want inside and, even if the back explodes its contents all over, I can still push my stuff aside and find room to sleep. In a hammock, that does not work. Being the heaviest object in the hammock, I become the low point of the floor, and everything else slides down to me, on top of me, or under me. Therefore, everything has to go somewhere else. If it goes inside, it must be hung from the ridgeline.

Hennessy has provided several nice options for storing stuff in the hammock. First, a mesh pocket slides along the ridge line so it can be placed where most convenient. It is separated into three compartments. In one of the smaller compartments I put those small things that are very important, such as contact lenses and lip ointment. The other small compartment held my tool necklace (LED flashlight, penknife, compass, and whistle). The larger compartment held everything else (except food) that I carry in my pockets while hiking, including sunglasses, reading glasses, maps, and comb. I found I could also put a small half-liter water bottle in there. I found this mesh pocket very convenient. I wish there were two of these.

The two small hooks on the ridgeline I have found less useful. My headlamp I simply drape over the line, and when I tried to hang a stuff sack to the hook the sack hung too low and bumped into me. I haven't found much use for these personally, but other users may find them helpful and they don't weigh much at all.
Gear hooks, mesh pocket, and carabiner.
Gear hooks, mesh pocket, and carabiner.

At the far ends of the ridge, the ridge line forms a small loop to which a small carabiner can be clipped to store heavier items such as day packs and water bottles so they don't slide to the middle where they would be in the way. I recommend attached these mini-carabiners (the kind stamped "not for climbing") before the hammock is set up, and then leaving them attached permanently. It is almost impossible to reach the far end above my head when in the hammock, and in any case the tension on the ridge closes the loop, making it hard to attach the biner in the first place.

At the head end of the hammock, I use the carabiner to attach a stuff sack or two, in which I can store other items I want to keep inside. The drawstring of the stuff sack is long enough to keep the sack close enough to reach but away from hitting me in the head at night. At the entrance end, I have used the stuff sack to hang my shoes by their laces, with the shoes hanging out the entrance so they are outside the hammock, keeping my sleeping bag clean but the shoes dry by hanging just under the hammock. I tried hanging a smaller pack in this manner, but found it in the way of using the entrance.

Extra clothing, such as a jacket, I just lay beside me, or under me as a pillow. My hiking pants and clothes I lay beside my sleeping bag. If the smell was not overpowering, I found I could hang my dirty socks from the ridgeline so they could air out without getting dew on them outside.

I also tried hanging my pack just outside the hammock, from the rope near the entrance. This worked okay, although it was just a little in the way, but on the other hand easily accessible by just sitting at the entrance. However, the pack was not fully under the hammock's rain fly, so it would have to be covered in foul weather. More often, I found it easiest to just hang the pack from a branch on the tree I had tied the hammock to.


By unfastening one side guy line and folding that corner over onto the hammock, I can sit on the hammock and use it as a chair that has some comfortable back support. Leaving the rain fly in place provides shelter from the sun or, if there was any, presumably rain. I did find half the time I had the hammock a bit too high to easily tie my show while sitting in this manner, so other tasks such as cooking would likewise require that the hammock's height be just right.


So far I have talked only about sleeping in the hammock. I have a number of "rituals" I perform before going to sleep: removing my contact lenses, changing clothes, reviewing the map of tomorrow's hike and making notes from my guidebook, and some devotional reading. Usually I do these in my tent. As comfortable as sleeping in the hammock is, these tasks for me are better done before getting in the hammock. While changing clothes in the hammock, an observer outside might well think a bear was wrestling inside, and, while one of my reasons for changing to sleeping clothes (usually ultralight silk long johns) is to keep my sleeping bag clean and odor free, it is almost impossible for me to change clothes in the hammock without getting my dirty pants on my sleeping bag. The other tasks generally need a work surface, like the floor of a tent. Lying on my stomach in the hammock is not comfortable for me, and in any event stretching my arms out in front of me in that position puts them high in the far corner of the hammock. Therefore, changing my contacts inside has left me concerned about losing them. Likewise, writing notes on my maps required some odd positions like half-sitting up on my side. I mention these not as criticisms, but as observations. Most of my friends seem to climb in their sleeping bag and go to sleep. Me, I have my rituals. As the weather and bugs cooperated, I did these rituals before climbing in the sack.


I love sleeping in my hammock. It is much more comfortable than sleeping on the ground. However, while I find the sleeping wonderful, other living activities are more difficult, such as reading in bed, changing clothes, etc. I need to think of it more as a very comfortable bivy sack rather than a suspended tent. My other difficulty is finding a way to secure a pad so I don't slide off it and wake up cold in the early morning hours.

This concludes my Field Report. The Long Term Report will be amended to this report in approximately two months from the date of this report. Please check back then for further information.


Over the next couple overnight trips I will continue to test the hammock in the mountains of Southern California, elevation 1,200 to 10,000 feet (300 to 3,000 meters). Temperatures 15 to 85 degrees F (-10 to +29 C) with a possibility of rain. I particularly will watch for durability, including seam stretching, fraying, and tearing. I still need to find a method to keep my pad under me to keep my back from getting cold in the early morning hours.

Two other specific testing objectives have eluded me so far. If I cannot meet these objectives on backpacks I will experiment with them on car camps or in the lower 20. Specifically:

  • Waterproofness: the drought continues. If it doesn't rain on a backpack, I will be ready to pitch the hammock in any storm at home to test for fly coverage and water running down the ropes.
  • I had intended to experiment with suspending the hammock from the trunks of large shrubs, such as over a ravine. In reality, I have found no such opportunities, as I could not get the hammock high enough to keep it from touching the ground when I added my (not-insignificant) weight to it, or could not find a location clear of underbrush such that I could enter the hammock readily. However, I will also use it one night on the ground as a tent as a test of its ability to provide shelter above timberline.



Since the field test I have used the hammock on an overnighter in the local mountains at 8,000 feet (2,400 m). Overnight temperatures were 60 degrees F (16 C) with little or no wind and clear skies. A few small mosquitoes were present to snack on my arms before bedtime. I also used it a couple times base camping just above sea level in similar weather conditions.


Sleeping on a cloud. That's the best way to describe sleeping in a Hennessy Hammock. There are no pressure points as the hammock cradles me gently. The netting has kept out all the nasty bugs, and the hammock has held up well even though it has been loaded to its weight limit.

Set up now takes me almost no time at all after I find the right site. My biggest difficulty, which has surprised me given that my trips have all been in the forest, has been finding two perfect trees to hang the hammock from in a place I want to camp. You see, I like to camp where there is a view, and that usually means the vegetation is more open. Finding two trees is easy, two trees the proper distance apart with a view has been more difficult. I've often chosen less-than-perfect trees to get a nicer campsite. This may mean a snag, or one tree that is too large for the provided Tree Huggers to reach around. As I previously mentioned, using two trees of different diameters requires just a little attention to getting the hammock level.

The SnakeSkins have proven to be a very clever way to packing up. Because the end of the hammock with the entrance is not easily identified when the hammock is packed up, I have made it a habit to always pull the SnakeSkin over the head end first, and then the foot end, so that the SnakeSkin coming from the foot overlaps the other end and is on top. This avoids having to untie the hammock and turn it around when I want the entrance to face a certain direction or not be located over a sharp rock.

So far the hammock shows no signs of wear. While I have taken care to avoid hangs that would cause the hammock to constantly brush against the brush, such contact has happened often during the pitch, yet no harm has occurred. The only flaw that has manifested itself is that the sheathing on the end of one of the ropes has pulled back from the inner core. I will fix this easily by trimming and melting the tip.

The one thing that detracts from my enjoyment of the hammock is the lack of insulation under me. On warm still nights, the hammock is a true pleasure. While temperatures during these tests have not been real low, on a few occasions they have been enough to feel the cold on my back coming through my (compressed ) down bag and the hammock fabric. I have found the best pad is a simple roll-up automobile windshield shade. Even that wants to slide out from under me when I scramble into my sleeping bag, and even when I toss and turn. It was an extreme pain on my last trip when a bad hamburger on the drive up caused me to get out the hammock many times during the night to look at the stars, as each time I had to wrestle to get the pad back in place under my sleeping bag. On the colder nights I put the pad IN my sleeping bag, which helped quite a bit. This will preclude me from choosing the hammock as my shelter during trips in cooler weather.

While the hammock has some creative storage methods hung from the ridgeline, larger items (my big shoes, for instance) would bounce on top of me as I moved. I now keep almost everything outside the hammock, except for those items I might need during the night, either hung from a branch or just left on the ground under the hammock. Because of the difficulty of some tasks in the hammock, such as removing contact lenses, I now do this outside before going to bed.

Unfortunately (because we really need it here), I have been unable to test the hammock in the rain.


For kicks, I tested pitching the hammock on the ground in the backyard. I used plastic sheeting as a ground cloth both to protect the thin fabric and because the "door" in this configuration is on the ground. I used my adjustable trekking poles to support the ends of the hammock, running the ropes through the straps and then tying off to stakes as I would a tent's guylines, and staking out the two sides by wrapping the side pulls around the stakes. Entrance was easier than I expected, although far from graceful, and I suspect in wet conditions would result in brushing against a lot of wet fabric. Because the ground (obviously) keeps the bottom of the hammock from forming a nest as it does when hung from a tree, and because I could not extend the trekking poles too high without raising the floor off the ground, the internal height of the shelter was very short, about 18 inches (50 cm), and the fly was lying on the mesh netting.

A short stay in the hammock in this configuration made me appreciate just how wonderful sleeping in the trees is, as I almost felt as closed in as when I have tried body bags, err, I mean bivy sacks. In practice, I would most likely pitch the rainfly by itself. This would also require the use of a separate ground cloth. The hammock body could then be used as a bug bivy if necessary. Still, it was nice to see this was an option during foul weather without trees to hang from.


I enjoy relaxing in the hammock greatly, and the level of comfort on a warm summer evening makes sleeping in the trees a true pleasure. While I miss the ability to spread my gear all over my tent, the comfort more than offsets that.

A few changes I would like to see:

1. Provide a method to secure a thin insulating pad (such as a windshield cover), perhaps using very light fabric to form a windproof sleeve under the hammock, so the pad does not slide around when moving inside the hammock.

2. Use contrasting fabric to outline the entrance, and also where the rope attaches to the hammock and fly at the foot end, to identify the entrance for ease when pitching the hammock.

3. The side pullout lines could be improved. First, the instructions don't explain how to use them (what angle horizontally? vertically?). They are very long, thin, and black in color, meaning they tangle and get lost in the forest duff in the dark. While I appreciate stealth colors, a lighter, more reflective, color would help, as would some simple aid to deployment. I tied tautline hitches in all of them, but even with the knot fully slid so the line was half the length, it was sometimes still too long. Often I just wrapped it around a branch or such, hoping it would hold as I didn't want to tie it too tight and have a mess to untie in the morning.

I would also recommend that users consider purchasing larger Tree Huggers, which are available from Hennessy as an accessory.


I look forward to pretending to be an Ewok on future summer trips. As the ground has gotten harder over the years due to the rotation of the earth, the hammock eliminates the need for large and heavy sleeping pads. Cold from beneath will limit the use to warmer weather, however.

Thank you for Tom Hennessy and BackpackGearTest for the opportunity to test this fine product and finally overcome my fear of "it just can't work for me." I now not only understand why

This report was created with the Report Writer Version 1. Copyright 2008. All rights reserved.

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