I apologize if this has been discussed before but having recently started flying off fairly small rivers, I seem to be behind the plane again and I am looking for any tips to help the learning curve. I'm having the most trouble once on the water particularly reading the river and what's under the surface.

If it makes any difference I'm flying a 206 on Edo 3430's.

Thanks!

I have been doing river work for coming on 6 seasons now, I figure in around 20 more I will have some sage advice. Both the rivers I work are silty so you can't see shit of the bottom. "Notes of a Seaplane Instructor" has some good tips in it, and if you youtube "reading a river" there are some good stuff mainly by river speed boat guys. What I have found so far:

the outside of a curve is faster current, and deeper.

when you are beaching it try to find a 'point' with an eddy behind it. Beach right down stream of the point at about 45 degrees to the bank and the eddy will give you enough time to get out and work the plane.

To turn from down stream to upstream get as close to one side (down wind side if there is a x river wind) as you can, put your flaps down, and start your turn at idle to get the smallest radius turn you can, after you get more than 90 to the upstream give it just a little bitty quick shot of power to get the water rudders a little more bite. If you have to, you can bump the outside (away from the center of the river) float and let the current bring your ass end around (make sure you have wing clearance)

The "books" say if the wind is at the same velocity or less than the current take off down wind with the current. Man, I am still making up my mind on this. I work a river with a fair bit of current and some decent bends in it, and when taking off down stream you use a lot of real estate, so know what is downstream. In that situation I have been taking off upstream, it takes more time (in seconds) to take off but less overall distance.

You can turn tighter on step that you can if you abort, dig in the heels, and try to turn. If you aren't flying and a bend is coming up, come off the throttle but keep it on step through the bend - if you kill it and pull back you lose air rudder authority and will be going just a bit too fast for water rudder authority.

Do not land downwind into the current, I did that with just a skosh of wind and the higher hull speed when I touched created a much bigger drag than I ever thought that it would, my nose came down radically even though I anticipated with a lower touch down speed.

I have yet to figure out how to turn around in a narrow river when the current and wind are the same velocity in the opposite directions. The float bump doesn't work because you vertical stabilizer will offset the current and you just sit in one place. I have learned to just get out and manhandle the plane to face up or down stream, stick it enough to hold it till I can pull it off with power.

If you are doing a quick drop off or pick up , just kill the pogwer with the mags so that you have instant power on start up.

The other that is applicable to river or lakes, as you load up, make sure you are still floating enough to pull it off with power. It is embarrassing to ask you customers to get out so you can 'unbeach' it.

(edited for this after thought) if you are going downstream and run aground, shut down immediately, do not at all try to power out of it, the current is already pushing you more aground, if you add power you will get even more stuck.

I would be super interested if anyone has any others, or, has good reasons that my ideas are incorrect.

Most interesting thread in a long time. Hoping someone in addition to Wes (good post) comes out of the woodwork.

Web site or computer are flaky this AM. Just wrote a loooong tome, which promptly disappeared.....grrrr.

I'll give it another rip later.

MTV

Good stuff!

MTV, When I compose a long post I always do it in Microsoft Word then copy/past it. That way if it gets lost I can just past it and try again. Looking forward to your post.

Zzz wrote:Most interesting thread in a long time. Hoping someone in addition to Wes (good post) comes out of the woodwork.

x 2

I've been wondering who would pipe up, seems like it would take a hell of a lot of experience to get really good at.

Headoutdaplane wrote:I have been doing river work for coming on 6 seasons now, I figure in around 20 more I will have some sage advice. Both the rivers I work are silty so you can't see shit of the bottom. "Notes of a Seaplane Instructor" has some good tips in it, and if you youtube "reading a river" there are some good stuff mainly by river speed boat guys. What I have found so far:

the outside of a curve is faster current, and deeper.

when you are beaching it try to find a 'point' with an eddy behind it. Beach right down stream of the point at about 45 degrees to the bank and the eddy will give you enough time to get out and work the plane.

To turn from down stream to upstream get as close to one side (down wind side if there is a x river wind) as you can, put your flaps down, and start your turn at idle to get the smallest radius turn you can, after you get more than 90 to the upstream give it just a little bitty quick shot of power to get the water rudders a little more bite. If you have to, you can bump the outside (away from the center of the river) float and let the current bring your ass end around (make sure you have wing clearance)

The "books" say if the wind is at the same velocity or less than the current take off down wind with the current. Man, I am still making up my mind on this. I work a river with a fair bit of current and some decent bends in it, and when taking off down stream you use a lot of real estate, so know what is downstream. In that situation I have been taking off upstream, it takes more time (in seconds) to take off but less overall distance.

You can turn tighter on step that you can if you abort, dig in the heels, and try to turn. If you aren't flying and a bend is coming up, come off the throttle but keep it on step through the bend - if you kill it and pull back you lose air rudder authority and will be going just a bit too fast for water rudder authority.

Do not land downwind into the current, I did that with just a skosh of wind and the higher hull speed when I touched created a much bigger drag than I ever thought that it would, my nose came down radically even though I anticipated with a lower touch down speed.

I have yet to figure out how to turn around in a narrow river when the current and wind are the same velocity in the opposite directions. The float bump doesn't work because you vertical stabilizer will offset the current and you just sit in one place. I have learned to just get out and manhandle the plane to face up or down stream, stick it enough to hold it till I can pull it off with power.

If you are doing a quick drop off or pick up , just kill the pogwer with the mags so that you have instant power on start up.

The other that is applicable to river or lakes, as you load up, make sure you are still floating enough to pull it off with power. It is embarrassing to ask you customers to get out so you can 'unbeach' it.

I would be super interested if anyone has any others, or, has good reasons that my ideas are incorrect.

Wow that was more than I was expecting! Thanks for your response. I'll definitely have to check out the YouTube. So far, I've only got stuck once on a submerged rock with passengers but it wasn't really a pleasant experience. As for beaching, when you don't have a point with a back eddy have you found anything to make that easier? Right now I'm having to beach offside and cross the wire to tie up, luckily this is a fairly slow river so you can usually get it semi stuck with power.

yep beach the the outside float at 45 degree or less angle to the beach and run across the wire is what I do. I have tried beaching 90 degrees but the current will rip it off the beach faster.

Wes did a good job. My only contribution is in regards to his statement about not being sure when to make the downriver takeoff...though he was talking about the specific case of a downriver wind that is similar to the water speed.

When they are both equal, it really is not clear to me which is the better option.

But what we encounter periodically is a float pilot that does not use the downstream water movement to help with takeoff even when the wind is calm. We have had a few planes in the trees on the Alagnak and elsewhere when a new pilot tries to take off upriver because they are more comfortable with upriver operations. The river speed is free airspeed, so UNLESS you have a wind that favors upriver operations, downriver is better for takeoff. And landing downriver is often a better idea as well, mostly because you have less water drag at touchdown.

People that struggle with this concept of using downriver as the default for takeoff and landing often have a lot of river boating experience, where upriver is almost always a better direction.

As for reading the river, so many variables. Find a person that knows it if you are dealing with a specific river and pick their brain. Go spend time on it in a boat. Anything to get familiar if you have any options.

Happy flying.

Thanks to all contributors, I’m slowly returning to recreational float ops after a 30 year absence as my “career” fly evolved. Lots to relearn and this sort of intel is invaluable, please keep it coming all is very good for the knowledge toolbox !!

Perhaps the most important words when offering advice in aviation, and especially in seaplane operations are: “It depends”.

There are a few things the seaplane pilot needs to understand and apply at all times when operating a seaplane on water. This is doubly true if the water is moving.

First, understanding the relationship between aerodynamic drag and hydrodynamic drag in a seaplane is absolutely essential. Overcoming aerodynamic drag is relatively easy, but hydrodynamic drag is, well, a real drag…..and a very powerful force.

So, on takeoff for example, the seaplane has to get onto the step first to reduce the effects of that hydrodynamic drag as quickly as possible. The drag of those floats in displacement mode is incredible. But, once on the step, the pilot needs to manipulate the controls to accomplish further reduction of hydrodynamic drag to the point where the seaplane can accelerate to flying speed. That is the primary task: Accelerate the airplane on the water to a speed where the airplane can fly. Now, that doesn’t necessarily mean you have to accelerate to Vso to make this work……ground effect (water effect?) is your best friend as a seaplane pilot.

Secondly, the make, model and powerplant the airplane is equipped with makes a huge difference in the performance of a seaplane, particularly in tough conditions. Also, different models of floats perform VERY differently on the same model of airplane. The older PeeKay 3500 floats had a fairly high “hull speed”, which made them very challenging floats to work, particularly in no wind condition. The “hull speed” is essentially the maximum speed which a hull design will move through the water without application of massive quantities of thrust. Those early PeeKay’s hull speed was very close to, and in some cases well below the stall speed of the airframe mounted on them. So, the pilot of these things really had to learn all sorts of “tricks” to get them to come out of the water. Fortunately, PeeKay (now known as PK) recognized this and fixed that issue in their later floats.

The point is, knowing your seaplane’s performance and “manners” is essential when you start operating in moving water. And, as usual in these kinds of discussions, the words “always” and “never” should be used sparingly.

There are situations where taking off up current is in fact the only way out of a particular stretch of water…..one comes to mind of a fishing hole on a fast river that has very short straight stretches. Land in there with a Super Cub on EDO 2000 or a Husky on Wips, and the best way to get out of there may be to take off upstream, because, as Wes pointed out, you’ll travel less distance up river during the takeoff than you would taking off downstream. Try that in a loaded 206 on PeeKay 3500 A floats, and it might not be such a great strategy.

In fact, I’ve worked seaplanes that simply wouldn’t take off upstream, even with a brisk downstream wind. That pesky hydrodynamic drag is powerful. Again, knowing the performance of YOUR airplane is essential in these situations. Once one of our pilots landed in the Porcupine River, with a downstream wind, in a 206 to pick up some folks. With a strong current and the wind in the same direction, the current prevented the plane from taking off upstream, even with a ten to twelve knot headwind. Heading downstream, the pilot was able to get on step, but there wasn’t sufficient room between river bends to accelerate. I landed there with a 185 on EDO 3430 floats, and, with two loads got everyone and everything over to a big lake. The 206 was able to (barely) launch downstream off the river stone empty, then pick up the load off the lake.
So, again, the operative term is “It depends”.

I like lines on a seaplane…..lots of lines. By the way, rope is the stuff on a spool at the marine supply store. Once you attach a hank of that rope to something, or put it to use with a knot, it becomes a “Line”, and is no longer a “Rope”.

I put a ~ 20 foot or so long line attached to the tail of a seaplane. A little shorter sometimes, but….. No knot on the end, no loop….you don’t want it hanging up on anything. Wrap it with safety wire, bury the end of the wire, then burn the end of the line to seal it.

I like lines tied to the forward float cleats….almost as long as the floats. Let them trail, and no, they won’t get in the prop. On bigger seaplanes, I like to have shorter lines attached to the bases of each forward vertical strut of the floats. I also like to have short lines attached to the wing tie downs. deHavilland knew something about seaplane handling when they designed in the wing tip rings found on the Beaver. Hang a short line on each of those, and you’ve got “handles” to help control the airplane.

One of my early mentors told me that his theory was that every aspiring seaplane pilot should learn to fly floats in a Single Engine Otter. His logic was that NOBODY is going to look at an Otter and think they can muscle the thing around on the water. But, most of us will mistakenly think we can muscle a smaller plane around, and find out the hard way that the forces involved in moving water are tremendous.

Go to a busy seaplane base and watch the pilots coming and going sometime. Docks or beaches, makes little difference. They make it look effortless, but it’s not. Point is, they’ve learned to FINESSE the airplane, to use the forces involved to encourage the airplane to go where the pilot needs it to go, rather than trying to muscle it around. This is a key in any seaplane operation, but it’s downright essential in moving water operations.

The question of how to judge depth in rivers: I don’t know, and I’ve done hundreds of landings and takeoffs in rivers, fast and slow. I have landed in the Yukon River many times….a big fast river, full of silt. Some stretches of that river are very braided, and those braids all look similar from the air. Yet, some of those channels will be 50 feet deep, and a virtually identical looking channel on the other side of an island may be only a few feet deep. The 206 I flew for a number of years there had a depth finder. I learned to enter channels ONLY while going UPSTREAM. Hit bottom while going downstream, and you WILL be stuck. Hit bottom going upstream slowly, and you’ll likely be able to get out and push the plane back into deeper water.

Find someone who really knows a stretch of water. Better yet, pioneer that stretch with a boat first, then take your seaplane in there. At one point, I needed to go to and from the village of Birch Creek, which is located on…..wait for it…..Birch Creek. The creek is fairly narrow, and not real deep in late summer. There is an airport there, but in summer I didn’t always have easy access to a wheel plane. So, I borrowed a wheel plane, flew to the village and borrowed a boat, during low water. I found a stretch downstream from the village that’d work, but there were a couple of kind of shallow spots and two bends in the stream between there and the village. So, when I returned with the 185 on floats, I landed in the nice landable stretch, kept the plane on the step around the two bends and over the shallow spots, and parked in front of the village. On departure, I fired up, got on step, and step taxied around the two bends to the takeoff stretch. Easy.

Sometimes, those are the sorts of machinations you would be well to perform BEFORE you risk your seaplane.

ALWAYS WEAR AN INFLATABLE PFD!! Did I overemphasize that? Especially in moving water, the risks are increased, and a PFD can save your life. Don’t even think about not wearing one, even on hot days.

Understand the forces involved. Learn what your airplane on your floats likes and what it doesn’t like. Watch others go about their work, and learn from observation. And, remember, often, advice given should probably be qualified with "It depends".

MTV

Huge thank you to everyone! This has been super helpful so far.

MTV - your comment on the powerplant making a difference sparked my memory. During my check out I was told to get the props back asap (io-520) and it will accelerate and climb better, now I don't have enough time on type to have conclusively tested this but why would a coarser pitch pull better at low speeds? I thought that's the whole reason cub drivers get the super fine pitch props?

Also, I hear you on lots of lines that makes perfect sense to me. What diameter have you found to work the best?

Now with step taxiing over shallow spots, I've often thought this could work as it's the same idea as a jet boat once on the step you draft a lot less water. But I've been hesitant to put it in my toolbox, so to speak, because I figured if you hit anything while traveling that fast it would tear the float for sure and probably flip you. You had gone through the stretch of water in a boat first wich is good but what gave you the confidence that the river wouldnt shift or change before your flight?

YES PFD'S WILL SAVE YOUR LIFE! I did an underwater egress course and one of the first things I realized was that if you aren't wearing one when you get in the plane. Odds are you won't find it once it's floating around the cabin post crash.

Troy - with the down river take off have you ever found that because of the waters movement it simply takes too long to get on step? I have yet to get winds that allow a downriver takeoff (at least while loaded, I've done a couple empty) so again I haven't been able to test it.

This is a gem of a thread. Thanks for the contributions.

Just started my Seaplane training so this is a awesome read.

Dclings wrote:
Troy - with the down river take off have you ever found that because of the waters movement it simply takes too long to get on step? I have yet to get winds that allow a downriver takeoff (at least while loaded, I've done a couple empty) so again I haven't been able to test it.

Boaters think of getting on step as a speed over water equation, and have a hard time relating to the advantages of a downriver takeoff because of the need to go faster to get speed over water for planing behavior, thinking of the floats as a boat keel.

But you are not flying a boat. Planing is certainly assisted by the floats, but you also have wings, which generate lift, which makes it so the float keels have less weight to get up onto the step...

...the water speed is free airspeed, so the wings are working harder to help. Conversely, going upriver, your wings are doing less, so the floats have to be more boatlike, and haul more load up onto the step.

So no, I have not found it to be a problem. Anytime I have calm wind or an upriver wind, I am happy to be able to make use of the downriver run. When the wind comes from upriver, I take off upriver. The case Wes mentions, where the river speed and wind speed are similar in the same direction, is the exception...I generally favor upriver in that scenario because of the improved control on the water and slower ground speed at takeoff, even if the book disagrees.

Great thread! Thanks to all.

I'm just a recreational float driver with most of my water time on high altitude lakes, so I have little to contribute on this river thread. I'll mention what I have that might be useful.

1. Dale de Remer's advanced book "Water Flying Concepts" helped me understand a lot that you don't get in the initial rating training. He and MTV would have a great chat about numbers and lengths of lines to have! Unfortunately, I think my ex-girlfriend has my copy and when I just went on Amazon to order a replacement, I found that it is out of print and used ones are going for over fifty bucks! I ordered a used one anyway because a.) I think that highly of the book, and b.) It's worth fifty bucks to me to NOT have to call that ex!

2. A few years back, I did some training on a busy commercial river near Vancouver (the Pitt, IIRC) with float instructor David Budd out of Victoria, BC. It was a lot different than playing on big lakes! Swift current, log booms, commercial boats, busy docks, etc. Two things I remember from that:

A. With a swift current, it is possible to point it upstream, give it just enough power to match the current, and use rudder to sort of "crab" sideways to the dock.

B. For departure from a dock where a failure to start would be "highly consequential", use a line secured to the dock with one wrap around a float step held in your hand. Only when you're sure the engine is running and gonna keep running, let loose and it should just slip away. I just had to practice doing everything else with my free (right) hand.

C. With an injected engine (which I have), to help ensure that the engine keeps running after a short shut down, as suggested earlier in this thread, shut down with mags rather than mixture cut off. Before starting, run boost pump a few seconds with mixture cutoff to purge the line of any vapor "bubbles" that could cause that awful engine shutdown a few seconds after you think it is running. That's worse than not starting!

3. On the Kennebec River in Maine I learned to verify the security of your buddy's dock before counting on it. Because of the "sail" effect, as Mike alluded, even a relatively lightweight plane can pull a lot harder than a similar weight boat!

Thanks again to all for the great questions and great contributions. That's one of the things I love about flying floats: always learning!

Pierre

In relatively narrow streams, it can be tricky to get turned around in the available width. Sometimes, it’s a good idea to beach and get the plane pointed the direction you want it. But that too has pitfalls.

BUT, find a bend in that stream, and you can get some help without beaching. The outside edge of a bend has the greatest velocity, while the inside of the bend has less.

If as you move upstream, you approach the turn in the outside of the bend and try to turn around, you’re shooting yourself in the foot. Put the plane in the inside of the bend, and turn toward the faster water found in the outside of the bend. As you come around, the toes of the floats are in faster current, the heels in slower water, and the plane will turn nicely.

Going downstream, and preparing to turn, approach the bend on the outside of the bend. Now, as you turn, the toes move into the slower water, with minimal resistance, while the heels remain in the faster, outside of the bend.

Try it, it’s amazing how tight you can turn when you use the physics to help the turn....

MTV

mtv wrote:If as you move upstream, you approach the turn in the outside of the bend and try to turn around, you’re shooting yourself in the foot. Put the plane in the inside of the bend, and turn toward the faster water found in the outside of the bend. As you come around, the toes of the floats are in faster current, the heels in slower water, and the plane will turn nicely.

Going downstream, and preparing to turn, approach the bend on the outside of the bend. Now, as you turn, the toes move into the slower water, with minimal resistance, while the heels remain in the faster, outside of the bend.

Try it, it’s amazing how tight you can turn when you use the physics to help the turn....

Us kayakers call that an ‘eddy turn.’

This thread is awesome. Makes me daydream about making a living on floats.

Got my float rating yesterday on Flat Head River (neither fast nor narrow), but this thread is great and extremely appreciated!

asa

asa wrote:Got my float rating yesterday on Flat Head River (neither fast nor narrow), but this thread is great and extremely appreciated!

asa

Congratulations ASA! Now your brain is polluted with visions and thoughts of float flying, poor guy!

Kurt