Tag Archives: packraft speed

Alpacka Yak 1 (Decked) Main Page

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See also:
Packrafting the Fitzroy River (NW Australia; 5 posts)
Alpacka Yak around Suilven mountain
Alpacka Yak to Suilven mountain
Urban Packrafting: the Death Weir Kebab Tunnel
Slackrafting to Clashnessie
Intex Slackraft vs Alpacka
Packrafting in France – Ardeche Gorge
Packrafting in France – Chassezac
Escalante packraft recce
Trying out bikerafting
Packrafting a Force 6 gale
Packrafting the Oscaig river
2011: Llamas get the point

After all that lot I sold my Yak and bought a non-decked, two-colour Yak in a 2013-14 sale

I’d parked the RV at the end of a 55-mile track south of the highway at Hole in the Rock, the top of a gully which drops 500 feet down to Lake Powell and which is bit of a scramble in places. If this was the Australia that I know, the chasm would be plastered with ‘Gorge Risk‘ signs. Looks like the Americans have got over all that, if it ever existed here. What you see – a steep, boulder-chocked gully where you want to take care – is what you get.

Getting down and back up from the lake wore me out for a day, but what was I complaining about? In 1880 Mormon pioneers spent six weeks here lowering two dozen wagons to get across what was then the Colorado river (read right) to get to a new settlement on the far side.
Once on the water I only went for a bit of a splash-about in a flooded arm off the main body of the lake as it was a bit windy and I wasn’t sure what weather lay ahead. By the time I got back to the top it had clouded over and stayed that way till I left the GSENM a few days later.
Changes on the conventional-looking pre-2011 rafts are summarised here: pointy ends, greater length, extended stern, 2-part backrest/seat and a deck that zips right off. I also have a feeling the floor’s made from a chunkier or stiffer fabric and so the extra butt-patch I had specified (left – done for free) may not be so necessary – but it sure feels worthwhile when scraping along a boney Scottish burn.

On the water first impression was not so good – oh dear the 4-inch shorter Yak was seemingly narrower at the front than my old Llama and I couldn’t put my feet side by side when pressed against the front (left image on the right) – this wearing size 11 Keen Arroyos (fairly wide). But deflating the backrest from full gave my legs more room and I actually found that both feet placed flat on the floor below the bulge of the side tubes worked fine (right image above right), just not so sure if this is so intuitive for brace control. I checked the front interior width of my Llama against the new Yak and it’s only an inch wider. In the picture left the new Yak and Llama fronts seem near identical in interior front width.


Getting back in the longer Llama, I now see the reason my feet didn’t jam was that I had a few inches gap between the front of my feet and the inner front of the boat where it tapered off. Sat against the back I could never reach the front to brace which is why I got the Yak. Also, the UDB on the new Yak may have constricted my feet a bit that day. Paddling a few days later without the UDB, I can’t say I noticed the foot jam. Got all that?


Other fascinating facts from my comparative measurements (above right) show the new Yak is only 8 inches longer then the Llama, so a new Llama ought only be 12″ longer, not 20 inches as estimated from the Alpacka website’s measurements at the time. The new Yellow Yak is nominally 4 inches shorter inside than an old Llama.

Other than that it feels much like the old Llama. Like they claim, turning/spinning doesn’t seem to be affected by the increase in length, but I’m sure the Yak’s bow yawed less from side to side as I paddled, due I suspect to the extended tail damping the paddle-induced pivoting effect, rather like a rudder or skeg. I did have my part-filled UDB strapped to the front where any weight tends to reduce yawing anyway. It was the first time I used the UDB on the water and have to admit the added guarantee of its girth and buoyancy was reassuring should a Colorado river barracuda make a bite at my Yak. Couldn’t really do any speeding in the conditions – it may be just half a mph faster, but that’s still some 20%.

As anticipated, the new 2-part seat is a real improvement. No more having the backrest flop down as you’re trying to get in quick off a steep bank or into a fast flow with a need to line up or burn. Like on my Llama, I just clipped the seat base onto the hull tabs with a single snaplink each side (inset, left) rather than mess about with the string they supply. Makes taking it out and drying/cleaning the insides easier.

Later on, washed up on the wrong side of the Virgin River Gorge in northwest Arizona, I also found the part-deflated backrest a handy way of portaging the empty boat – a bit like a Sherpa’s headband (left).
So, bottom line, not a huge difference in operation apart from less yawing which was never that bad anyway once you compensated for it. Can’t say I noticed any added buoyancy/better trim with the longer back, but it might be noticeable from the other PoV. The zip-off skirt is a nice idea; one less thing to unroll and dry after. The added snugness I dare say I’ll appreciate in rougher conditions and it sure is nice to have a yellow boat for a change!
There was a discussion on BackpackingLight about the new shape and here Roman D gives his opinion for a harder core of white water utility. More pack-Yak adventures this summer.


Packraft MYO sailing

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First sunny spring day around here so we went out to try out the flip-out disc sail I made over the winter on my Llama and Steve’s Big Kahuna. Wind was forecast at about 8 mph but was gusty – a bloke in a dinghy sailboat said it was up to 15 mph.
Folded and clipped on the packraft, the sail sits out of the way and can be opened and – more importantly – closed easily with a twist, as long as you have a clip of some sort to keep it closed (and that clip is attached to the sail so it does not spring off and sink to the bottom of the lake…).

Initial impressions were disappointing, I did not rip off across the reservoir like a hooked marlin out of a Roadrunner cartoon. But watching the vid back it’s clear the boat did noticably drift downwind across the reservoir with the sail aloft, often at speeds similar to paddling (about 3 mph). Problem with the sail on the Alpacka was the boat soon turned off the wind one way or the other, swinging left and right. The pointier Kahunayak was better, especially once Steve trailed his paddle like a skeg. Didn’t get to try that on the Llama as I was fiddling about with the string trying angle the sail so as to steer the boat into the wind. This worked quite well in correcting the direction as you can see in the vid, but staying in that position was a problem.
Could this be due to ‘wind-spill’ off the flat disc sail which lacks dishing like a WindPaddle? Maybe. It will be interesting to try it on my ruddered Incept IK when it turns up, as well as the new-shape Alpacka which I am picking up next week.
More testing to come this summer up in windier Scotland with my all-new packboating flotilla. Or just enjoy this 2014 video from Finland by JP. More here at leftbound.

Inflatable kayaks: Do you Need a Skeg (Tracking Fin)?

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Updated Summer 2022

See also:
About rudders
About decks
Skeg-wheel trolley!

Short answer: Yes.

Generic, over-tall Chinese-made skeg.
Snap-prone but easy to trim.

A skeg is like a fixed ‘rudder’ under the back of the boat and makes it easier to go straight (track). Only the very cheapest single-skin vinyl IKs don’t have skegs (Grabner, one of the most expensive IKs, is an exception; though it’s an option). If you’re IK doesn’t have one, it’s easy to glue one on (see below).

grabgumskeg

Some flat-floored IKS have up to three (imo, a gimmick) and many skegs on Chinese-made IKs are unnecessarily tall (too deep) which makes them snap-prone. Just about all skegs can be easily removed by hand, because in shallow rivers you might want to do so to avoid grounding. You can as easily buy a spare and trim it with a hacksaw.

fitskeg
Gumotex skeg glued to a Grabner Amigo
Original over-sized Gumotex alloy skeg on the left. Later smaller; now tough plastic.

Years ago Gumotex introduced a slip-on, black plastic tracking fin (skeg, above) which was near identical in shape to one I’d had made to replace the old-style oversized alloy skeg (left). A smaller skeg made better clearance and still tracked fine. But metal bends; tough plastic is much better and that’s what all their boats come with now.
I’ve fitted these plastic skegs to older Gumotex IKs and other IKs. The kit is about £25 + glue, and the plastic skeg is pretty much unbreakable. Just make sure you glue the mounting patch on really well; it helps if your boat is made from a matching rubber fabric as the supplied Nitrilon patch or make your own patch from same fabric. But I have glued PVC to rubber successfully – use good two-part glue. The pictures below help you see where to position a skeg.

On shore a skeg is a pain with a loaded boat
Skeg: underneath and at the back
Gluing a Gumotex fin to a Grabner (which come with no skegs)

I fitted the Gumotex plastic skeg to my Grabner Amigo IK (above) and at sea used it all the time. But on the shallow River Spey (below) this boat didn’t handle at all well without a skeg, possibly because the tailwind pushed the kicked-up stern around. It was really quite annoying because a few years earlier my broadly similar Sunny managed the Spey just fine without a skeg, so skeg-free tracking clearly varies from boat to boat.

spey1304

Paddling without a skeg
If you’re an experienced paddler you’ll have acquired the knack of going straight without a skeg – handy for paddling shallow rivers where the skeg would ground. A little more paddling finesse and constant small corrections are required, especially if powering on.
It’s good to learn this technique before you need to: fix your eyes on a tree or marker on a distant bank and paddle as gently as you like towards it, not looking away and keeping the nose of the boat in line with the marker. By using very light strokes you’ll see it can be done if it’s not too windy when again, a skeg helps with tracking (going straight).

cezesolar
Gumo Solar with no skeg

I even found I could paddle a ten-foot Solar 300 (above) without a skeg. Once you know you can go straight without a skeg, it’s just a matter of adopting the same finesse but with a bit more power. Only when you attempt the speeds of a Viking longship will bow deflection or yawing get too much because to paddle faster and still go straight you need a skeg. Out at sea or on busier rivers, I always use a skeg.

IK&P Tip: drill a small hole in your plastic skeg and attach a ring or zip tie directly to you boat. It’s annoying to turn up and find you misplaced your skeg.

I’ve often thought a hinged retractable skeg would be a good idea: it would pivot backwards when dragging in shallows, then drop back down when there’s enough depth. It seems SUPs need skegs and in the US, FrogFish have made such a thing for boards, but you hear the spring can be a weak point.
If your kayak has a rudder mount (or you can make one), another way of doing it is fitting a swing-down skeg similar to kayak rudders. It works the same way as a rudder with a looped cord swinging the skeg up over the stern, or down into the water. The pivot skeg shown top right is made by Advanced Elements for their AirFusion IK and costs about $/£80. Or have a look here.

frogfish

Packrafts

On shorter, wider, slower solo packrafts the consensus used to be that skegs made little difference. Especially when unloaded and with a full-weight paddler, the bow yaws merrily left to right as your paddling pivots the boat from the back. Or so I used to think until I tried the skeg on my Rebel 2K. Up to then I’d been ambivalent about them – using the same boat fully loaded a few weeks earlier on a fast flowing river, yawing had not been an issue. But unloaded (and with my generous 95kg of ballast) yawing was notably reduced with a skeg. Speed however, was the same or was too small to measure.

If you think about it, a packraft actually pivots from a point around the middle of your swinging paddle, not from the stern, as it feels from the seat. The centre of mass behind the pivot point does make an unladen bow yaw more, but the stern will yaw too; just less and unnoticed.
Longer stern puts you more in the middle of the boat.

One reason some packrafts may manage without a skeg is that way back in 2011 Alpacka invented the ingenious extended stern (right). It helped limit yawing much like a skeg, and effectively positioned the paddler more centrally, like a kayak, while also adding trim.
This idea has been widely copied by just about everyone since and it definitely works, compared to the original Alpackas. But as mentioned, once there’s a good load over the bow, yawing is reduced in any packraft. Anfibio sell a detachable shallow skeg and glue-on patch for €21. My Rebel 2K came with a skeg and I must admit I use it most of the time now. But it does not have a fully extended stern like the Alpacka above right. Then again, my longer Nomad tracked great without the skeg.

S1 - 9
Skeg on an MRS Nomad. Tbh, tracks great without it
Skeg on an Anfibio 2K. Reduces yawing

Frontal skeg?
Now I have a longer 2.8-m Anfibio Sigma TXL and I am curious to see if adding a frontal skeg will take a difference. Seated centrally or two-up, this boat does not yaw from the boat like an unloaded solo packraft, but it does wander a bit (track poorly), especially with the inflated floor pad). Results soon.