Kevin R

Some flying boats have a problem unsticking from dead calm water, I hear. I wondered if it would reduce the suction effect when the plane is on the step, if a small pipe was fitted from under the centre of the step, to atmosphere, to eliminate the vacuum effect. Has anyone tried this idea?? I am building an Anderson Kingfisher, and thinking about fitting such a pipe before I paint the model. (The "air" end of the pipe could point forward, with a trumpet intake, to provide a bit of pressure)

TPAGEL

My Feedback: (6)

Calm water not a problem. All you need to do is taxi around a bit to create small ripples, then take off across the ripples. I fly off a small lake and we have calm water sometimes in early morning and this method works very well.
Tom

seaplane

I've heard that Tom's method is also used by full scale pilots. They taxi around to create so ripples, then take off thru them....Seaplane

JimCasey

My Feedback: (1)

PBYs used to have a problem with smooth water so the Navy would just send a coupla' destroyers out to churn up the harbor.
PBYs had small steps, and were heavy and underpowered. Takeoff at 95, cruise at 100, stall at 90......Fortunately, model airplanes have large enough steps to avoid the problem PBYs had with breaking suction.

Also, yes, ventilated steps have been used on models. You can build a soda straw into the float to supply air to the area behind the step. Airscoops, trumpet bells, or compressed-air desuctionizers are not necessary. If the step is high enough (1/2" or more) it's completely unnecessary and more trouble than it is worth (potential leaks, etc.).

The edge of the step should be sharp, and generally 1/2" or more, but it's really affected by scale. With the high power-to-weight and low wingloading of models, you won't have a problem, unless you use poorly-designed or badly-rigged floats.

The fun part is LANDING on glassy water. As you fly your airplane down, you will be able to see its reflection. Just make sure the reflection and the actual image touch very gently, and you did a good landing.

Kevin R

Thanks for the info. and tips, everyone!

vupilot

On glassy water full scale pilots with regular floats (not flying boats) just lift one float out of the water with the ailerons and accelerate to take-off speed on one float, cutting drag and "suction" by half.

Goinstraightup

My Feedback: (26)

Never had one hint of problem with my SeaCruiser. Works great calm or rough (like the day of the pics below). Most RC flying boats have generous thrust compared to weight, so much that the suction is not a problem. I've seen people have trouble getting into the air float flying, but it was always an incidence, balance, or thrust line problem. One of those will keep you on the water far more likely than suction. I think you will be fine.

Jeff

Ed_Moorman

My Feedback: (1)

Jeff,

Our Sea Cruiser makes the prettiest water take offs I have seen, skims along as nice as anything, but when you first add power, it wants to submarine. And it even in taxi, it covers itself with water. I was wondering how yours is right when you hold full up and add power. I get the feeling I might need some up thrust.

TPAGEL

My Feedback: (6)

Ed
I'v been flying my Sea Crusier for over three years now and have never had a problem like you describe. I think I would try some up-thrust and see if it makes a difference. I really don't hold much up elevator when applying power either, it seems to get up on the step real quick. You kind of gave me the itch to try the Sea Monster and when I found out it was on sale for $ 149.00 I couldn't resist. Going to be a while, the ice is still about 28 inches thick on my lake.
Tom

Goinstraightup

My Feedback: (26)

My experience is almost identical to TPAGEL. Mine does not submarine either. Sounds like some up thrust would be good. My SeaCruiser does get pretty wet taxiing, taking off and landing due to spray and how low it sits. Despite the wetness, I've never had any internal water problems as I put Vaseline around the front hatch and I have a silicone wing seat that I also put Vaseline on before flight.

Jeff

GRANT ED

I have the seamonster and sometimes have the same "sticky" problem. I have found that I can 'bounce' the model off the water by using elevator.

jaka

Hi!
Have no problem taking off in calm water...much nicer to do take offs then.
Kyosho PBY Catalina flier.
Jan K
Sweden

Pilot Chad

My Feedback: (4)

jaka, Flying submarine?

teemto

Jaka - As far as I remember You have altered angle of attack of the wing in Your Catalina (according to the original one from Kyosho ARF). Have You changed the wing only or both wing and horizontal stabilizer. What is the resulting angle then in Your Catalina??
I'm asking, because I just found the kit in my local hobby shop and ... I couldn't resist . And now is the time to finish and fly it and I'm going to fly off water of course. So I try to collect some additional info on Kyosho Catalina.

Neo02

Hi Kevin,
yes it works, had this system test-wise installed on a F3A-floatplane a couple of years back. It isn't very scale or very attractive to look at (although many asked me "what is it?"...) Other options include building VERY light or - as it has been said - create small ripples and take off through them.

Regards,
-Fabrizio