Packraft dynamics

Reducing spin:

if you look at how your butt sticks down deeper in the water, vs how much of the mass is in the back too, vs trying to keep it headed down river, it seems that it is akin to trying to shoot an arrow with the feathers on the front, and all mass is in the back.
there is nothing really keeping the front end pointed the desired front end'y direction.
the poor things (older ones were worse) are absolutely unstable in the forward direction, but mine are quite happy to stay about 70 degrees out of whack drifting downriver. it can be hard even to take just a picture they wander about so much.

question :

does anybody know if when one is drifting on smooth water at say 3mph, are you going EXACTLY the speed of the water, or sliding down a river which comprises a very large ramp, and thusly going a slight bit quicker ?

cheers,
peter v.

> or sliding down a river which comprises a very large ramp?

Consider the extreme case of boating over a waterfall (do NOT try this at home, kids): Are you "sliding" over the surface of the water, as you accelerate at 9.8 meters/second^2? The water is accelerating at exactly the same rate so are, at all times, moving at exactly the speed of the water.

On a 1% gradient river, the boat and water are likewise subject to a small acceleration of gravity, the same for the boat and for the water. For the water, that small acceleration force is balanced by frictional forces on the water against the river bottom and river banks. For the boat, friction from moving through the air dominates. If there was no atmosphere (1) you would die, (2) the river would flash to water vapor, but (3) you would be ever so slightly "sliding" over the water. Just as streamlines of water have shear relative to each other (no slip at the river bottom, increasing speed toward the center of the channel), there would be a slight shear force retarding the boat's ever so slightly higher speed. Here's your basic velocity distribution during laminar-flow in an open-channel:

showing how, in the middle of the river, velocity is faster. With drag against an atmosphere, the surface is a bit slower than deeper water. With no atmosphere, the fastest water would be furtherest from any edge – in the center of the channel at the surface. Imagine the raft as more of the same – further from the drag of the river bottom and banks – and ever so slightly faster than the fastest water.

Michael – I've had success w/a kayak anchor (http://www.seattlesportsco.com/productcart/pc/viewPrd.asp?idproduct=2154&idcategory=127) but definitely not "UL". This is good for when I'm basically using the packraft directly out of the car to load fishing gear and hit the water. The current in the Potomac tributaries I frequent can get strong so I would not trust a stuff sack nearby; in theory it sounds good but I think the stitching on most bags would rip w/the tug of the packraft+you+current. Might be a fun test to see the load bearing capacity of a certain stuff sack. Maybe a properly tied knot directly around the rock would work? YMMV – This may work though on calmer bodies**EDIT: Maybe using a fabric deadman stake bag/patch (a la http://www.rei.com/item/725165/rei-snow-and-sand-tent-anchors )would work better since they are designed to handle more tension? Add a few more knots & that just might do it…

Remaining stationary…still working on that. Other than being mindful of wind+current the only thing I've done is occasionally throw out a 2nd line to shore/anchor points if available. Yeah, I know, definitely not always an option. I've had success using an old drybag for drift sock – I know your OP seems weary of this but wanted to confirm it works.
2 anchors may be the only way to stabilize a raft in open bodies. Kinda heavy but that might do it.

Michael, how’d things ever workout with your packraft fishing? Did you find good solutions to your issues? I’ve got a packraft on the way and hope to fish on most of my trips.

How about a bag full of rocks or sand?  Only need to carry the bag and rope. Find the rocks and or sticks when needed

My main mode of self-powered coastal transportation for many years was a sea kayak. I like making videos of my trips, and a sea kayak is a great platform to shoot video from. From the standpoint of yaw, it’s very stable. Packrafts are absolutely terrible in this regard. It is so amazingly frustrating to try to shoot video from a packraft even in calm conditions. I’ve tried to sort of wedge my paddle in my arm pit and use it like a rudder, but it’s awkward and never seems to work out correctly. I can’t really entertain the luxury of deploying something into the water like a sea anchor and then retrieve it, because I’m handling photographic equipment and need dry hands.

@Andy, I’ve read that just using a plain old stuff sack might not work, as it’s not built for that wear and tear, but there’s this neat looking collect-your-own-rocks anchor – https://www.nrs.com/squid-lightweight-boat-anchor/pqvd – which also comes in smaller capacities.

@Philip, with regard to yaw, I wonder whether a small “parachute” might work to provide just enough rear drag in flowing water to keep reasonable downstream orientation. I’d love to be in sync with the river for fly fishing, but if moving just a hair slower kept my boat pointing in the right direction, it might be worth it. (Ha, as I’m writing this, the slightest bit of research suggests that my intuitive idea and the sea anchor are one and the same. ;-) ) Fortunately, most of the time, I’ll be hoping to get my hands wet with fish anyway!

Looking for a way to slow down my drift while fishing from my packraft and just found this thread.  I have tried tying an anchor to the raft.  It almost sank me.  I was on a big lake in pretty high wind.  once I got to the end of the rope, all of that tension was stretching/pulling the raft tubes down into the water.   Every wave was coming over the side and pouring water into the boat.  had to pull up anchor in a hurry and then trudge to shore to empty out the boat.  If there was a way to tie the anchor near the very bottom of the boat it probably wouldn’t pull the tubes down as far and might work, but all of my tie down points are high up on the raft.  It’s not something I’ll be attempting again though.  at least not while I’m out in the middle of a big reservoir.

My long-practiced rule is to never use more than 15-pound test from my kayak (when fishing) because there are things out there that I don’t want to catch.

I’m thinking the same thing for an anchor.  Find a longish rock, put a constrictor knot around it (a clove hitch but with an extra twist under the top pass of the line.

Then deploy the rock as an anchor / drag device.  If it gets stuck or wrapped around a log, you can give it a good tug, snapping the line at the rock, and retrieve all the line.

My fishing buddy is very clear to his wife and others when asked, “How do we raise the anchor to retrieve a man overboard?”.  You don’t, you just cut the anchor line, make the rescue, go home, and buy a new anchor.