In 2008 I got invited on a Grand Canyon trip for 2009. A friend of mine who had done several trips hooked me up with a guy who was moving east and wanted to sell an 18' twin tube cat with flat frame and four oars for $1,000. It had a few nicks and patches but held air well. I built new decks using the old ones as templates and took it down Westwater and Cataract in April of 2009, and finally the Grand in June.
It was an amazing boat: fast, super stable, and nimble. Research suggested it was a Chinese copy of the Aire, and probably from the early to mid-90s based on the valves. It charged straight through massive waves, no problem. But it was a wet ride and took a ton of straps - the lower decks between the tubes were hung a couple inches above the water using just straps. I'm not sure it would have been easy to right if I flipped, but I never came close to that.
Here's the boat at Lava, coming in at 0:40.
Lava Rapid Grand Canyon June09 - YouTube and Bedrock at 1:05,
Bedrock Rapid Grand Canyon June09 - YouTube, Crystal at 0:38,
Crystal Rapid Grand Canyon June09 - YouTube Upset at 0:41,
Upset Rapid Grand Canyon June09 - YouTube . I carried my share of the group stuff and picked up my girlfriend at Phantom; there was plenty of room for gear and I felt the boat was a lot less vulnerable to flipping than a raft with less tube for a wave to grab onto. They just came right through and out the back. I had to rig a strap up front for my rider to hang on!
I loved the boat but it was a bitch to rig, so for most rivers I used my 14' Otter. The big cat was set aside in a garage in Arizona for several years, and the heat and dryness ruined the glue. I tossed the tubes but kept the frame, decks, and oars. Someday I want to put it back in service. The only tubes I see that would work are these:
Cataraft 18 Foot Double Tube Expedition Class 5 QuadCatt Does anyone have experience with QuadCatt?