Float operations in fast flowing river

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sportingrifle
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Float operations in fast flowing river

Post by sportingrifle »

Hi All....

I am a relatively low time inexperieced float pilot. Next month I will be operating a Beaver into a probably fast flowing river in Norther British Columbia. (Homathko, at the head of Bute Inlet) I am not expecting much wind as it will early in the morning. The river flows from N to S, as does any wind. Any thoughts as to techniques or things i should be concerned with? What are the pro's and cons of landing into the current as opposed to against it?

Much appreciated,

Sportingrifle.
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glorifiedtaxidriver
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Re: Float operations in fast flowing river

Post by glorifiedtaxidriver »

Not too much to worry about on landing. If you land into the current you will have less ground (water) run after touchdown. If you land down current you will cover more water than normal to come off the step. Sometimes more than you think. Make sure you do a good inspection before you land so you don't accidentally go too far and end up on a sandbar. Give yourself lots of room landing down current. Also, once you're on the water, you will find that if you are turning from down current into current your water rudders will be less effective, meaning you won't turn as fast. Also, dock into the current, even if it's on the passenger side. If you have to takeoff down current you will use more water than normal to become airborne. If you're heavy, you won't get on step as fast.
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Rowdy
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Re: Float operations in fast flowing river

Post by Rowdy »

Sporting.. be wary of your assumptions about winds and time of day.

I've been into bute a handful of times and toba more than I can count. With a strong outflow wind it can get pretty nasty in there regardless of time of day.. I've seen it blowing 20kts at 7am in toba and then flat calm at noon. Best to plan your takeoffs and landings to favour the wind and the terrain and then just remember as glorifiedtaxidriver stated that there will be a change in distance depending on whether your into or out of current. Also be mindful of snags and debris.. this time of year with all the runoff it can catch you off guard, especially if the river is moving fast. Have a good look as you flyover every time. It'll also change as the tide goes in and out..

How far up the homathko?
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sportingrifle
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Re: Float operations in fast flowing river

Post by sportingrifle »

Hi taxidriver/rowdy....

Many thanks for your thoughtful replies. We are staying at the old logging camp at the top of Bute the first night and then proceeding up into the Chilcotin the next day. While I have your thoughts, any hints for the take off? I am assuming that if space permits and all else being equel, a down current take off would be preferable?

Many thanks,

sportingrifle
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Meatservo
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Re: Float operations in fast flowing river

Post by Meatservo »

No. I think generally, if you can go up-current and upwind, is the optimum situation. Going down-current seems preferable at first, but when you think about floatplanes taking off, the first thing to matter is the speed of the hulls through the water before the speed of the wings through the air becomes a concern. Taking off into the current gets you on the step in much less distance than down current, and feels more "natural", which is important if you're still developing your skills.

It's a complex issue, at least to my mind, which flows like a lazy river itself. I have several scenarios I think about when faced with rivers. If it's a shallow river with a short run. I like to go up-current in order to get on the step as soon as possible, even if I have a small tailwind. The tailwind is OK if you can afford a longer run once on the step. With a strong wind blowing opposite the current obviously taking off into the wind is better, but allow yourself more room for the run onto the step. Remember it's the speed of the hulls through the water that lifts you onto the step; not the wings.

It's something you need to consider as the situation dictates. In general you already know that once you are on the step, the higher the headwind, the shorter you will take off. BEFORE you are on the step, the greater the head current, the shorter you will get on step. Sometimes the two situations will combine for better performance, sometimes they will detract from one another. Generally if getting on the step is important I will favour departing against the current. If it's not important but initial angle of climb is, I will favour departing upwind, but allow myself twice the normal amount of room for the initial run. The aircraft will feel funny in the case of the wind flowing opposite to the river, because at liftoff the floats will be travelling through the water more slowly than usual, making the water feel "sticky". Conversely going up current but downwind, the floats will be going through the water faster than usual for a given airspeed, making the plane feel slightly unstable because the floats will feel "ready to fly" slightly before the plane itself is.

To summarize: Upwind+upcurrent=good; Downwind+downcurrent=bad; and the other two combinations require some consideration at the time and place.

If you're docking in the river, it can be disorienting for a beginner. Docking into the current is obviously preferable, even if this is on the right hand side of the plane. It would take a pretty strong tailwind/slow current to make me want to dock a Beaver with the current. Docking up current allows you to approach the dock very slowly while still having good flow over your water rudders.

Other than that, it's fun! Remember boating skills are as important as flying skills!
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High and Behind
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Re: Float operations in fast flowing river

Post by High and Behind »

Also, remember that when at taxi speed you have good rudder authority when pointing into current. But when you try to turn down current your turn radius can increase dramatically. When you are broad side to strong current your basically drift wood. And will need a $h-t load of power to get around your turn. Then your taxi speed down current is quite fast but you will have reduced rudder authority.
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Cat Driver
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Re: Float operations in fast flowing river

Post by Cat Driver »

So turning from up current to down current in a river is like doing a down wind turn in the air?

You run the risk of losing control even if your speed in the water does not change?
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180
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Re: Float operations in fast flowing river

Post by 180 »

Sportingrifle,

Unless you absolutely HAVE to go into Homathko Camp, I would save yourself the stress and overnight somewhere a little more floatplane friendly.

I've been in there a few times. It's as high performance as it gets. Fast moving water. Narrow. Debris. Tight landing zone. Tricky take-off area. Dock is in a corner with a dangerous back eddy immediately down stream with an ugly plane crunching shoreline. Water temps barely above freezing. Off-side docking. Fun. Fun. Fun.

You best be on your A-game going in there...
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xsbank
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Re: Float operations in fast flowing river

Post by xsbank »

That turn thing is funny - there is some small inertia effect but the major effect is that you'll be looking at the shore and not the river when you turn and it will seem like the turn takes forever as the drift illusion messes you up. You are moving through the water at the same speed up or down current so your water rudders work fine in either direction. Remember Flying 101, the Illusions of Drift? Same thing.

I also agree with the other poster to stay out of Homathco Camp unless you are pretty good at your game. Its been a while but you might be better at Southgate. The cold air falling down the Homathco Glacier cannot be ignored; sometimes the outflows are breathtaking and Bute becomes ugly.
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I_Heart_Seaplanes
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Re: Float operations in fast flowing river

Post by I_Heart_Seaplanes »

Dont know where you are located, but the Fraser is honking right now. Here is my favorite place to practice on fast rivers.

https://maps.google.com/?ll=49.180694,- ... a&t=h&z=16

In regards to the turning upstream/downstream topic. The "time" to make the turn will be pretty much the same. Its the "distance" that you need to be prepared for. On the Fraser yesterday, it took me about 200ft of shoreline to go from down to upstream. Something to keep in mind if you have boats/bridges/shallow water downstream of you dock.
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Mooseman
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Re: Float operations in fast flowing river

Post by Mooseman »

You can taxi up stream a bit and take off down stream if the wind isn't a factor. Stay on the river as it bends a bit to the right. U should be airborn before the turn and pick up ur airspeed over the water before climbing out. If I remember correctly, there is no place to go if ur low coming up stream. Don't piss around after u turn to take off. Don't be afraid to use a bit more flat if ur heavy. Just remember what it does for u and to the plane when ur slow and bleed it off before reducing power once u break water. If that doesn't work for u then tell them to make it to the head of the bay for pick up. Don't be afraid to pull the power and try again.
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sportingrifle
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Re: Float operations in fast flowing river

Post by sportingrifle »

Thanks to all who shared their knowledge. Given me lots to think about. As it turns out, for unrelated reasons the airplane may be doing the trip on wheels anyway but either way. it is a great thought provoking thread. Also, . is willing to make space on the inside of the dock if he knows your coming to allow for onside docking and to protect the aircraft from junk in the river. Looking forward to the trip.

sportingrifle
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Meatservo
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Re: Float operations in fast flowing river

Post by Meatservo »

Mooseman wrote:You can taxi up stream a bit and take off down stream if the wind isn't a factor. Stay on the river as it bends a bit to the right. You should be airborn before the turn and pick up your airspeed over the water before climbing out. If I remember correctly, there is no place to go if you're low coming up stream. Don't piss around after you turn to take off. Don't be afraid to use a bit more flat if you're heavy. Just remember what it does for you and to the plane when you're slow and bleed it off before reducing power once you break water. If that doesn't work for you then tell them to make it to the head of the bay for pick up. Don't be afraid to pull the power and try again.
There.. this was good advice so I took the liberty of fixing up the spelling. Idiocracy was a funny movie, but we're not there quite yet.
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wobblepump
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Re: Float operations in fast flowing river

Post by wobblepump »

+1 with 180

If your docking where i think your are...
-land a little short and stay on the step to get upstream to the dock as the overshoot options are poor at best
-morning is definitely better, a tailwind will make your safety envelope smaller and your float to water speed go even higher
-there can be debris near the backs (opaque water)so plan it so you don't have to turn around(an inflow wind also makes this more dangerous)
-Once your on the water, buddy and his loyal dog will guide you in with helpful finger pointing
-the same man will tie you to the dock, keep your engine running while he does this as the water was moving about 8-10kts last year around this time (funny vid of a beaver who shut down before the rope was tied is out there somewhere)
-docking onside while taxiing downstream is not an option
-watch for debris while on the slide going upstream, there was some ugly looking sticks near the middle of the river

Don't mean to sound like a pussy but this place is full on, watch your tail feathers
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beaverbob
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Re: Float operations in fast flowing river

Post by beaverbob »

Sportingrifle,
Sorry I never saw this in time for your trip to the Homathko. I have been there dozens of time. I Just want to know if you went in there and if so How did it go for you?
Bob
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TeePeeCreeper
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Re: Float operations in fast flowing river

Post by TeePeeCreeper »

Homathco river... Isn't that where Ralf Edwards Taylorcraft met its maker back in the 60's?

For those of you unfamiliar with Mr. Edwards also known as the "Crusoe of Lonesome Lake":

http://www.youtube.com/watch?v=tOuRJCei ... ata_player

Truly a pioneer in every way!
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robertsailor1
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Re: Float operations in fast flowing river

Post by robertsailor1 »

Read the book years ago and sure enjoyed the vid, thanks for posting.
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sportingrifle
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Re: Float operations in fast flowing river

Post by sportingrifle »

Beaverbob et all....

Thanks for your replies. To answer your question, due to payload constraints, we swapped the airplane to wheels and just worked off the strip. This was a great opportunity to check out the river first.

. is a super helpful guy and we all enjoyed his hospitality and comraderie. His operation at Homathko is first class and I am looking forward to going back.

Cheers Sportingrifle
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beaverbob
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Re: Float operations in fast flowing river

Post by beaverbob »

TeePeeCreeper wrote:Homathco river... Isn't that where Ralf Edwards Taylorcraft met its maker back in the 60's?

For those of you unfamiliar with Mr. Edwards also known as the "Crusoe of Lonesome Lake":

http://www.youtube.com/watch?v=tOuRJCei ... ata_player

Truly a pioneer in every way!
in the 1950's Mr and Mrs Edwards used to stop in at Telkwa, where my dad had a seaplane base. Thay stayed overnight sometimes and brought us the most wonderfull candied vegetables and fruit they made themselves.


Too bad about the homestead burning down.
Bob
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