doenute: to quote you; "Now, with blades tracking within 0.035"(yes, did it with an indicator), significant vibration below about 1200 RPM, then it calms down above." Tracking the trailing edge tips of the individual propeller blades from a position on the transom with perhaps a weldi...

Interesting video on gyroscopic effect. I realize gyroscopes isn't the topic, but it demonstrates the forces in action. The idea being the propellor can already be up to speed and then pitch can be added. This would cancel gyro effect of an accelerating mass. Imagine the launch speed of a race boat...

HP Question diggingfool answers 7-9-13 “If the design speed of the prop is 2,200 RPM, and assuming reducing pitch is going to raise the engine speed from 4,900 to 5,200 RPM, what is going to provide the best overall performance for the boat? I assume that all things being equal, my boat is currently...

July 8, 2013 Radtech asked: “I'm curious about the rollout transom. I assume it will let down after the boat is on plane? With the engine in the bottom, and the possibility of prop striking incoming water, I'd think that wouldn't be good. (but what do I know. lol) Awesome overall design and love the...

Congo Cargo Boat replies to SA Thread 7-7-13 By David Wine Lake Wales, Fl 33898 Picking up questions again; Whitebear: Thanks for the early post. We have twin 60” diameter counter-rotating 3 blade propellers that are inter-leaved in the same plane. There will be no torque roll or boat turning force....

You would do well to listen to plums advise on the ecotech motor. There are a lot of naysayers when it comes to this motor but that is only because they are not yet aware of its performance. The new ecotech 2.0l turbocharged for 2013 has 270 hp and 295 ft lbs of tq from a motor that only weighs 310...

Water Walker’s NEW Congo Cargo Airboat. As we worked with the tests mentioned in the previous post (Driver Adjustable Prop on the Water Walker Concept AirBoat), we were also searching for possible ways to further improve the design principals of airboats in general. Articles were posted as well as ...

July 5, 2013 Lake Wales, Florida By David Wine Water Walker Props, Inc. A Report, The Driver Adjustable Prop on the Water Walker Concept AirBoat. https://fbcdn-sphotos-b-a.akamaihd.net/hphotos-ak-prn2/965618_10151783838828573_34023744_o.jpg In the late fall of 2011, David Mosser (aka “Plumcrazy”) vo...

OK that worked now for a picture of the whole boat; http://i1264.photobucket.com/albums/jj482/winedavid/IMG_0781.jpg [/URL] OK if that worked again, the red boat in the picture is our boat also and it was an 8' X 13' airboat with a GM ZZ-383 stock engine, Blue Lightning Drive (2.3/1 belt). This &quo...

Diggingfool: Learning with the pictures: Here are pictures of the "Blue Ox" boat that I spoke of earlier in this thread with the ZZ-502 engine. Looking at the bolt layout of the three blade prop hub, I can see that it is a "long Hub" which would be an 82" disc. Flyingfish: I...

Very cool concept. What would happen if the wake washed up into the props? All hell would break loose, except that the "Variable Geometry Transom" is "Live" spring loaded and snaps up tight when the prop blast subsides (off throttle). It takes power & thrust to lower for pla...

Thanks, folk: Here is my attempt to post pictures; http://i1264.photobucket.com/albums/jj482/winedavid/4.jpg http://i1264.photobucket.com/albums/jj482/winedavid/3.jpg http://i1264.photobucket.com/albums/jj482/winedavid/2.jpg http://i1264.photobucket.com/albums/jj482/winedavid/1.jpg These are renderi...

Diggingfool: July 2, 2013 Good Afternoon. Deano, Flyingfish & Blackwater: Thanks After rising this morning, I scanned for what my autopilot had worked out through the long night and my attention went straight to the pitch reference mark. Clues have been; “White Mark”; At the shipping tables in C...

June 30, 2013 Diggingfool: OK, let’s “dig” a little deeper here. You said earlier that you were an engineer. I put that together with your avatar name and guess “Operating Engineer”. So I will do the math for you for the question you asked about “how many degrees equals 3/16” along the circumference...

From your exact tune. 30 HP more for every 1 degree of added pitch to reach same governed RPM . Suggest selling your boat to defeat Ghost you are at battle with. Exact boat has been described to accomplish your goals. Horsepower, reduction and blade to produce ghost defeating thrust. :to banghead: ...

Digginfool: I have come to realize that you are not seeking a technical answer but rather are looking for justification to have a monster engine on that otherwise great looking boat! The most dramatic “justification” that I’ve come across was some years back when Ole Bruce Kay, that developed your S...

Oops:
Change that prop math to "2017" prop RPM.
sorry about that.
David Wine

@Coondog - - - Power is power. He has a very heavy (when fully loaded) boat. He currently only has 465 hp. More gear and different blades is not the answer for a lack of power, more power is. Simply can't escape the reality of the power/weight ratio. The engine, gear ratio and the prop are all very...

Irony; Airboat shows up as miss-spelled in an air driven boat forum word processor!!!!

DuckBoat: Your rotations are correct. Your pictures however show girlie looking props with good curves and tiny tips. Personally I have always liked larger tips. Curves are always good. The following explanations apply mostly to slower speeds in displacement conditions. When going fast and in a soli...

Keith: interesting post & comments: The following is a worst case scenario of gyroscopic + torque roll forces in an airboat maneuver that is very likely to sink you: Take a; Right hand rotation large wide say four blade propeller on a, Gearbox installation that mounts the engine higher than a be...

April 15, 2013 Chuckett & Wild Bill: First to Wild Bill’s questions; My first engine description on this thread spoke of Permanent Magnet position sensors and large computer power in the engine controller. The controller would be aware in real time of the radial position of both the main ring ge...

OK, well this thread sure went South soon enough!! Nuclear powered airboats? Really? Maybe me and Cowboy aughta just stay with our little 200 Lycomings and let you boys dream up the big stuff. Wow. Olf Art: In defense of the Grand New South, I take offense for myself and all good southerners of you...

I would propose a micro nuke power plant. We now power aircraft carriers to submarines and whole space craft with a larger version them. The actual drive system part of the boat of course would be a stem plant using steam from the nuke plant part. Maybe a new type of electric motor will need to be ...

April 14, 2013 Lake Wales, Florida Good Morning, (I’m in a steady state of mourning since 2008.) This thread (Airranger’s) specifically asked for a “clean sheet of paper” approach to an conception ally new airboat specific engine. I have and am responding in that perspective. (Perhaps someone would ...