Updated May 2022
Sharing information, experience and opinions. There are no affiliate buying links here.
• Hybrid IKs
• Full review: Sandbanks Style Optimal FDS
• Full review: Shipwreck ArrowStream FDS
• Guest review: Aqua Marina Tomahawk Air-K 375 FDS
• Paddling with a Yakkair Full HP2 FDS
• Preview: Advanced Elements AirVolution FDS
• Preview: Decathlon Itiwit X500 FDS
• Preview: Gumotex Thaya hybrid
• Preview: Gumotex Rush hybrid
• Preview: Advanced Elements AirFusion hybrid
• Preview: Aquaglide Chelan 155 hybrid
• Buying direct from China (2017)
• Floors on 3-panel FDS IKs
As predicted here years ago, eventually a way would be found to make an inflatable kayak entirely from rigid dropstitch panels. Something a bit more sophisticated than an iSUP board with a strap-on seat.
Even before the worldwide IK boom of 2020 there was a lot of interest in FDS IKs, and this despite supply issues which continue today. Potential buyers view them as superior to traditional round-tubed IKs, while gaining the performance benefits of a hardshell. Now in 2022, all prices have dropped, some by nearly half as demand has returned to normal. It could be a good time to buy, assuming the availability is there.
Certainly any FDS is miles better than a low-end, 2-psi Sevylor or Intex, nor do they all have the days-long drying issues of Shell & Bladder IKs (but see below). And right now you can buy a two-seater PVC FDS for under £700, including a pump and paddles. These boats are well put together, too: I’ve not read of burst or peeling seams, anomalous leaks or panel misalignment issues. The worst you hear of are lightly damaged, dirty or seemingly returned boats being sold as new to unhappy buyers, usually from online sellers at the very lowest price range.
Sea Eagle led the way in 2016 with the three-panel Razorlite and now there are a score or more of near identical full dropstitch (FDS) IKs, like the ArrowStream, above. Then in 2020 Advanced Elements’ released the AirVolution: a two-panel clamshell design. A couple of others have released similar IKs, not all of which are AE clones (see below). I predict that among recreational day paddlers these two-panel clamshell FDS IKs could catch on over the slab-sided, three-panel ‘open coffins’. Meanwhile, the basic one-panel design (see above left) is just an iSUP with a central cockpit to sit it. More below.
Some FDS inflatable kayak specs
|4.5m 14.5′||94cm |
|10 psi |
|Tahe (formerly Bic)|
AirTrek Pro 440
|*Sandbanks Style Optimal||20|
What is Dropstitch?
Dropstitch IKs actually started as easy-to-fit DS floors derived from iSUP boards with the kayak’s round sidetubes retained. These are still popular and are now called hybrids, but all the boats on this page are Full DropStitch (FDS).
For the full story on dropstitch (DS) click this. Short version: a dense mass of non-stretch ‘space yarn’ is magically stitched between two fabric sheets at thousands of stitches per square metre. The dimples you see on an inflated panel surface is the space yarn under tension inside, a bit like on a mattress.
Once formed into a flat, airtight board, on inflation via a proper raft-grade valve, a DS panel can handle much higher pressures than a round-tubed IK, especially one with a wide floor made of laboriously assembled parallel tubes. With DS we’re talking 10-12psi (0.8 bar), up to six times more than a low-end tubed Intex. Like an iSUP board that you can stand on, an FDS is practically as stiff as a hardshell while still rolling up into a (huge) bag.
It’s this ability to make a stiff form from an inflatable chamber which has been the weak link with traditional all-tubed IKs, especially once lengths increase and when used solo (weight in the middle; below).
Some manufacturers like Advanced Elements (‘Backbone’), former Feathercraft’s Java, plus Russian Nortik and Ukrainian Neris combine metal floor frames and supports with PVC inflatable side tubes to help give shape. But packed bulk, possible damage or loss of metal parts and extended assembly times (above left) means that, in their own words: ‘[Neris] are not inflatable boats’, they’re more like folding kayaks with inflatable sponsons, even if they perform very well once on the water. These kayaks are more suited to long tours where they’re left assembled for days or weeks at a time.
For ease of assembly, dropstitch solves the rigidity problem. Chamber/s at 10psi eliminate longitudinal sagging while enabling sea kayak-like lengths of well over 4 metres (13′) which adds up to more room inside as well as a much better glide (less propulsion effort).
This doesn’t mean all all-tube IKs are saggy bin bags. With any tubed IK running 4.5psi/0.3bar or more, the sag is negligible. Examples include my rock solid Grabner (left; all Grabners run 0.3bar), my Incept K40 and my modified Gumotex Seawave 1). I believe these boats perform as well if not better than most FDS IKs, as well as being less bulky and lighter. While I can see no benefit in swapping my well set-up Seawave 2 for any FDS I’ve seen or tried, boats like mine have become expensive enthusiasts’ IKs that aren’t banged out in China. The benefits of today’s many rebranded FDS IKs are hardshell-like stiffness and glide at a Chinese-made price.
Initially FDS IKs were made of three flat panels resembling the wooden canoe, right. On a tubed IK, round side tubes up to 30cm in diameter take up a lot of space inside, making the boat very wide – a lose-lose. DS panels are typically just 10cm/4″ thick while retaining all the benefits of tubed IKs: light weight and buoyancy.
The only downside with FDS seems to be bulk: there’s up to four kilometres of space yarn in a typical 4.5-metre FDS, though it’s more probably the lashings of stiff PVC which makes them hard to roll up compactly, especially when cold. Result: an FDS can end up twice as bulky as a similar-sized tubeless rubber boat.
Two-panel FDS IKs
In 2020 Advanced Elements came up with the AirVolution (below left): two iSUP planks wrapped at the sides, the top one having a cockpit aperture. A shallow fold in this top panel helps water run off while making a tiny space under the decks at each end.
Sandbanks Style’s Optimal (below left; full review) uses a similar clamshell design, except the floor also has a shallow V keel to aid tracking. AquaTec’s Ottawa Pro (above right and video above) is another two-panel FDS, and I now see DS Kajak in Germany appear to have dropped their three-panel FDS IKs (still sold in Asia) and now offer a two-panel AirTrek Pro (below right).
This iSUP-sandwich design makes these IKs wider at the waterline than just about all three-panel examples. But it also means they’re innately more stable, both on the water and when getting in and out – an issue heavier paddlers have has with slimmer three-panel FDS IKs. With little space under the decks you lose out on interior storage and maybe a bit of speed, but most kayakers are day trippers so the former doesn’t matter, while the rigidity of DS reduces the paddling effort compared to mid- or low-end, low psi IKs. You might even be able stand up in them and iSUP along. They’ll be dead easy to reboard from the water, that’s for sure.
As mentioned at the top of the page, while I doubt manufacturing and assembly costs are cheaper, I wonder if these two-panel IKs will eventually outsell three-panel designs.
Single-panel iSUP IKs
The inexpensive Costway aka ‘GoPlus’ (left; 330cm x 81cm; 14kg) is a single FDS board with a cockpit hole with a floor sheet glued underneath, just like a packraft. Quite clever, when you think about it. Into that you slip a separate DS floor panel to avoid sag. This sits you lower than just sitting on an iSUP board which means greater stability and something to brace the back and feet off. There’s an upturned bow too, but the GoPlus is otherwise just a board. It will be dead easy to clean and dry.
As with all IKs with DS floors, you’ll be sitting on a hard panel and so the seatbase becomes important. A thin bit of foam won’t be comfortable for long; an inflatable cushion or less wobbly soft foam will improve matters and also set you higher for a better paddling posture. Raised seats can create instability, but at a yard wide at the water, that ought not be an issue with two- or single panel FDS IKs.
Tracking (going straight)
Just about all of these FDS IKs come with an easily fitted slot-in skeg or tracking fin that’s often as tall as Flipper’s fin. Like a fixed keel or rudder, skegs help the boat go straight. Some IKs even have more than one, again under the assumption that more sure looks better. A tall skeg will drag in the shallows and the boat can’t easily be sat on flat ground without stressing the fitting. But any skeg is easily trimmed – or buy a spare and cut it down for shallow paddles. More about skegs here.
Some three-panel FDS boats also feature rigid moulded bow and stern pieces (below right) to help slice through the water. This is typically a weak point on broad-nosed tubed IKs (below left).
With the formed bow and stern pieces, box-like profiles and plank-flat- floors, a three-panel FDS IK can have zero rocker, meaning these boats track well but are hard to turn without a rudder. Many owners report that they glide as straight as an arrow. This was my experience too with a DS-floored Moki II and the FDS Shipwreck, but on the latter it was much improved by removing the skeg. Consider trimming an over-long rear skeg or not using additional frontal skegs.
Three-panel FDS IKs are crude box shapes because, excepting the Decathlon X500, making anything other than flat DS boards is too complicated and expensive. The design and handling of these FDS IKs is limited by these constraints: wind-prone flat slab sides, flat floor, minimal rocker. On top of that a DS floor can make them as uncomfortable as a hardshell, but adding a foam seatbase, stability can take a knock.
This Tomahawk owner said his boat’s initial (or ‘primary’) stability was a bit shaky, but once on edge was quite stable and took a lot to tip right over. This was on flat water. In more kinetic conditions things can happen too fast for you to react. This is why I believe the two-panel clamshell design will be better for most paddlers. Above all you want to be stable in your kayak.
IK World ran a comparison between her old style DS-floored Sea Eagle FastTrack and the 393 solo Razorlite, as well as giving a fuller review of the 393. You may like to scroll down and read some of the readers’ comments about issues and returns they’re having with early RazorLites (the very first FDS IK). She mentioned the Razorlite is less stable, but to me the stability of the yard-wide FastTrack seems beyond the pale until I tried a similarly wide Sandbanks and didn’t really notice it. A bit similar would be nice.
I felt quite safe in my 69cm-wide K40 right up to the point when it was coming in over the sides. But the 83cm-wide FDS Shipwreck is actually just 60cm wide at the waterline where it counts, and I (quite heavy and tall) found using the 6cm-thick seat base made it feel very tippy. Removing the foam from the seatbase resumed normal service.
One thing I’ve found on the FDSs I’ve paddled is the hard floor makes a comfortable seat base much more important. On the two-panel Sandbanks, an air cushion didn’t work like it does on softer tube IKs and packrafts because it wobbled around under my weight, even when deflated to minimum.
A foam block won’t wobble but needs to be just the right density to support your weight. I found the removable 9cm-thick foam block on the 3-panel ArrowStream made it too tippy for me to even risk letting go of the jetty. Other 3-panel FDSs are wider at the waterline and so will be more stable, but expect to find the usual inch-thick foam seats uncomfortable after an hour.
And don’t forget a substantially raised seatbase higher your heels makes for a better paddling posture. More on seats here.
Not for the first time I saw my ideas adopted by manufacturers: a simple footrest tube with an adjustable strap which I came up with a years ago! It’s so much simpler and more versatile and effective than the mushy pillows still used by Gumotex. KXone, Gliders and Shipwreck all use a padded tube on a strap. Would you have padded pedals on a pushbike? The again, many FDS IKs come with nothing.
I see Sea Eagle now use adjustable footpegs on the sides of their latest three-panel Razorlite models. It would only work well on hard DS sides and is the same system you’ll find in a hardshell – probably the most effective and comfortable, if perhaps buly and break-prone.
In any type of kayak, a footrest helps you connect with the boat, execute efficient strokes and not slide down the seat as you do so. And as an IK doesn’t have the benefit of a hardshell deck to brace knees off, a solid footrest is all the more useful.
Spotted a mistake or have something to add? Your comments are welcome.