"Build a Fuel Efficient Four Passenger Quieter Airboat"

A general, non-powerplant specific, discussion on airboat technology, ie., hulls, rigging, polymer, etc..
Rich Andrews
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"Build a Fuel Efficient Four Passenger Quieter Airboat"

Post by Rich Andrews » Sun Nov 13, 2011 3:11 pm

I have been following the recent posts by David Wine (Water Walker) and by private email, I asked him to send me the article he once mentioned back to me that he wrote. He did and I found it interesting enough to feel it is worth posting here for all to see. It would be interesting to see everyone's comments on it."


March 22, 2011
By David Wine
Water Walker, LLC

To Build a Fuel efficient Four Passenger Quieter Airboat

Airboats have evolved over most of the last century. Certainly none of these hard learned lessons and developments need be discarded or be forgotten in designing a new airboat that meets today’s needs of high performance, fuel efficiency and low noise. Among these well understood design features are;

Weight and Balance

An airboat of any design or size should float well at rest in open water and in all phases of forward speeds. Together these flotation and planning features are known in the nautical world as the boat’s “Hydro-statics”. There are computer programs now that can accurately and interactively predict these hydro-statics. A PC computer program known as “Autoship” can do this.

Center of Gravity, comparable to the Center of Mass

Place an imaginary hook at some point within the boat’s overall shape from which if you could lift the boat with an imaginary cable, the boat would not tilt forward, rearward, left or right no matter what position you start with even from upside down. This center of gravity should be as low and close to the waterline as is possible and practical.

Height of the Push Point above the Waterline

The push point is considered to be the center of rotation of the airboat’s propeller. As this push point is higher from the waterline and the boat is brought under increasing power the nose of the boat is pushed downward with greater force creating greater resistance and drag from the water against forward motion. Shorter airboats create a more dramatic pushdown angle from the push point to the waterline so longer airboats are better against this downward force.

Did you ever wonder why an airboat requires such larger horsepower compared to a bass boat? A typical bass boat propeller in the water is angled slightly downward to effectively lift the boat hull upward at planning speeds and thus reduce waterline resistance. Compare this to an airboat with its thrust line typically at four to five feet above the waterline creating a force that pushes the boat deeper into and harder down on the water for much more planning resistance and drag. So longer airboats are generally better and lower push points are always better.

Transom width and planning surface area

There are many design concerns in this area and the one that mostly controls is the width of an airboat trailer to be legally used on the roads. With lights and fenders a trailer should be no wider than say 8’- 6”. So one should build an airboat with a transom width of no more than eight feet that would fit onto this trailer.

More square feet of bottom surface area results in a quicker lift up onto the surface and acceleration to planning speed. So again longer is better to get more planning surface when the width is restricted by trailer constraints. Also because most airboats are this eight foot width or smaller, airboat trails in the swamps are not wider. The resulting eight foot width and cage construction together with minimum push point height also works to constrain the diameter of the airboat propeller. Without these constraints larger diameter propellers would be better.

Speed of Prop Wash/Blast

Seldom thought of as a design constraint, the prop wash velocity is of huge importance. For the safety of persons, wildlife and property it has been standard that the speed of the air exiting from the rear of an airboat does not exceed say about 100 MPH. Airboat thrust is the result of thousands of pounds of air being accelerated over time from still conditions to high rearward speeds.

At maximum power and RPM, how much air per minute is being accelerated to 100 MPH behind a 6’ Water Walker Signature Series propeller at 2800 RPM? Again, do the math and find that;

Air at sea level and at about 70 degrees Fahrenheit weighs 0.0747 pounds per cubic foot. In one minute this propeller has accelerated about 250,000 cubic feet of air weighing about 18,500 pounds to 100 MPH velocity. The reaction to this rearward acceleration of mass is your thrust.

Propeller Diameters

Four pounds of continued static thrust per HP at maximum RPM has been an optimum of airboat propeller efficiency. Water Walker’s Signature series of propellers for aircraft engine powered airboats have achieved this efficiency. Airboats with 300 HP angle valve Lycoming O-540 engines turning 2800 RPM using Signature Propellers have measured consistently at or above 1200 pounds of static thrust. These Signature Series propellers are typically 6 foot diameter and have a disc area of 28.27 sq. ft. A little math shows this equals 10.61 horsepower being delivered to each sq. ft. of propeller disc area.

At the beginning of World War II, (1942) the Consolidated PBY 5-A Catalina flying boat was the state of the art. It had two wing mounted engines and propellers. The engines were 1200 HP each driving propellers which were three blade aluminum, with 12 foot diameters. This computes to 113.10 sq. ft. disc area each divided into 1200 HP equals again exactly 10.61 HP delivered per square foot of propeller disc area. Because the laws of physics are immutable this nearly optimal 10.61 HP per sq. ft. of propeller disc area as a design objective does not change over time.

The tractor engines of the PBY 5-A had an upwards mounting angle that tended to lift the 23,500 lbs (empty weight) flying boat’s hull out of the water as it accelerated to its liftoff speed of about 75 MPH. 23,500 / 2400 HP equals about 10 pounds of flying boat/airplane per HP. This compares to a typical airboat’s range of 4 pounds of airboat (empty weight) per HP. This comparison is to illustrate the huge cost of HP required for an airboat to have a “Pusher” style of propeller setup (high push point) that pushes the airboat downward into the water instead of lifting the boat as the PBYs and bass boats do.

Higher Horse Power Boats

Now let’s look at a typical 500 HP automotive style engine with a propeller reduction unit to achieve a propeller RPM of about 2100. Using 10.61 HP per sq. ft. of disc, we should have a propeller diameter of 7’ 9”. The math is as follows;

To achieve four pounds of thrust per HP totaling 2000 pounds of static thrust, this 500 HP engine combination should have 500 HP /10.61 sq. ft. computing to be 47.13 sq. ft. of disc area. 47.13 / Pi equal 15. The square root of 15 equals 3.873 feet radius. 3.873 X 2 equals 7 foot 9 inches propeller disc diameter. (Say a 7’ 9” propeller diameter with a three blade set.)

The problem here is that at almost 8 feet diameter, this propeller is very nearly as wide as the trailer-able airboat with no room to build a cage. It also requires the push point to be placed at more height from the waterline which makes for a less stable airboat requiring lost HP needed to overcome the exacerbated greater “push down effect”.

These constants and reasons in physics are why monster HP engines on roadway trailer-able airboats are increasingly less efficient. So what has been done with these massive HP engine airboats to overcome these constraints? (For starters, understand that every trick a builder might try drops off in efficiency from the optimum of 10.61 HP per sq. ft. of disc area constant that can produce four pounds of thrust per HP). Builders have tried shorter propeller sets with more individual blades, wider propeller blades and more pitch as examples. All of these examples rob energy from thrust and loose it into increased propeller aerodynamic drag, more torque to the boat and increased swirl into the rearward airflow from the airboat.

Examples of actual boats

About a decade ago, I commissioned a larger airboat with the (then new) ZZ-502 GM crate engine that delivered 502 HP. We used an 8’ X 16’ Aluminum hull. We used a geared reduction unit at a 2.38 to 1 reduction unit which drove a right hand rotation Maximus Series 82” diameter (6’ 10”) 3 blade propeller set. This very successful, nearly un-stoppable airboat was known as the “Blue Ox”. While tuned to peak performance, we measured 1650 pounds of static thrust.



The 6’ 10” propeller diameter utilizing 36.67 sq. ft. of disc area computed to 13.69 HP delivered per sq. ft. (502 HP/36.67 sq. ft.) The 22.5% extra HP loading of the propeller disc area resulted in a drop of 350 pounds of thrust from a possible 2000 pounds that would have been available from a 7’ 9” propeller diameter as computed in the preceding paragraphs. This was a 21.2% loss of thrust and demonstrates that the loss was almost directly linear to the extra loading of the disc area. However an 82” (6’ 10 “) propeller is about the most that can be fitted into a cage on an eight foot wide trailer-able airboat.

The lessons learned said yet another way is that the premium pump gasoline that the ZZ-502 engine required is near $4.00 per gallon now and the configuration of the Blue Ox wasted about 25% because of the combination of constraints described above. Trailer-able airboats with 600, 750 and higher HP engines have been built. Their performance efficiency falloff was predictable by the above considerations and of course they had to carry even heavier “monster sized” gas tanks. As will be explained later every gallon of gas on board at 6 lbs. per gallon requires about 1.5 HP to haul around.

With 100 octane low lead airplane gasoline now costing around $6.00 per gallon, automotive premium pump gasoline touching $4.00 per gallon, anticipated new noise laws and the above physical constraints, what then is currently an optimal airboat configuration and design?

Let’s try to assemble a modern new “State of the Art” airboat.

Considering the previous discussions of propeller disc area where a nearly optimal HP loading per square foot of propeller disc area has been determined to be 10.61. An 82 inch diameter disc with 36.67 sq. ft. area is about the largest size that can realistically be used on an eight foot wide trailer-able airboat without excessively raising the push point above the waterline. If we multiply 36.77 by the 10.61 HP loading, it results in a HP range of 389.10, (say 400 HP) as the most powerful engine that can achieve maximum efficiency from this propeller. So let’s baseline a 400 HP, lightweight, small block, crate engine. As explained below, this is a better choice than an aircraft type engine.

Light weight is a key objective throughout these following design choices.

From previous research I have determined that a typical Lycoming IO-540 Angle Valve aircraft type engine produces 300 HP at 2800 RPM. This aircraft type engine, with its accessories (carburetor, starter, alternator & wiring, etc.), typically weighs about 435 pounds. This computes to 1.45 pounds of engine per HP.

While aircraft engines have been favorites for airboats in the past, their negatives now are too much weight per HP, they have to turn up to 2800 RPM propeller speed (noisy) to achieve the 300 HP, and they burn very expensive (now over $6.00 per gallon.) aviation gasoline. Also not widely known and appreciated by airboaters, these engines types were designed when 100 octane low lead aviation type gasoline was nickels & dimes per gallon. They were designed to run rich for internal valve cooling and thus are not nearly as fuel efficient as water cooled modern automotive engines of equal or higher HP ratings.

My latest (2011) GM Performance Catalog still offers the lightweight ZZ-383 “Stroker” crate engine. This engine with its required (factory recommended) accessories weighs in at about 400 pounds and makes 400 HP @ 4800 RPM with 420 ft. Lbs. of torque. Using premium automotive gasoline, this engine produces one horsepower per pound of engine. This is an ideal engine choice for a modern airboat. Because this engine HP very nearly matches the base line of 10.61 HP per sq. ft. of an 82” propeller disc we can expect to develop approximately 1600 pounds of static thrust from our airboat. (Please note that the propeller model to be used has to also to be nearly perfect in its aero dynamic design). Also, at 82” disc diameter, we can still build a trailer-able airboat. Note also that this is just 50 pounds less thrust than was developed by the previously described “Blue Ox” airboat with its 502 HP engine.

The ZZ-383 engine weighs 200 pounds less than the ZZ-502 for a lighter airboat and the smaller engine burns considerably less gasoline. A typical 8 X 16 foot airboat weighs about 2000 pounds requiring at least 1400 pounds of static thrust to be a good performer and be able to “run the hill”. This is about 1.4 pounds of boat per pound of thrust. So 200 less pounds of engine weight saving compared to the ZZ-502 equates to about 150 less pounds of thrust needed for equal performance as compared to say the Blue Ox airboat described earlier. With an anticipated 1600 pounds of thrust, we can now predict that our new 400 HP boat will perform better than a 500 HP airboat with considerable less fuel burn because we optimized the propeller disc area and used a lower weight engine.

500 HP is 25% more than 400 HP and all things considered will produce 25% more noise to contend with. Our using 100 less HP while gaining in performance give us an important and basic advantage in reducing the overall noise of our new airboat.

Noise (pressure waves in the atmosphere) is created by converting energy into sound waves. Consider a 200 watt “Boom Box” that is optimized for creating noise while playing on the tailgate of a pickup truck at full volume will nearly drown out an airboat. 200 watts is less than 1/3 of a horsepower. (One HP is equal to 746 watts). If our 400 HP engine was used directly & totally to create maximum noise levels, it could produce sound levels equal to about 1200 Boom Boxes.

It is a wonder that airboats are not noisier than they are considering all of this energy is put directly into the air at the rear of the boat. It is truly a tribute to modern propeller design that they can absorb this energy and convert it to thrust as quietly as they do. Still, we can now make this airboat quieter so as to operate below the anticipated typical 90 db measured 50’ from the airboat regulations.

Now is a good time to de-myth the idea that the propeller alone makes the airboat noise. The propeller just delivers the noise that is created by the large horsepower of the engine burning the energy of gasoline. While this might not be an exact analogy, imagine a person in a building that for the first time sees a glass window with sunlight pouring in. He might easily believe that the window is creating the light waves. I realize that this example is silly but think about it.

Sound energy is cumulative and the muffler and exhaust system of an airboat is very important. I believe there are some miss-conceptions out there about airboat exhaust systems. There is no reason that an airboat exhaust system cannot reduce engine power pulse noises to the levels of a modern pickup truck. The idea that because the propeller makes so much noise the exhaust system is not important is “wrong-headed”. In our boat, I will choose GM “Rams Horn” cast iron headers with thick wall stainless exhaust piping to stainless steel automotive mufflers sized to the 400 HP engine. This will give us quiet engine performance with little or no loss of power.

Water Walker, LLC has developed a carbon corded belt driven engine propeller reduction unit that is made mostly from machined aluminum, is light weight and very responsive. It is called the “Blue Lightning Outdrive”, has a reduction ratio of 2.3/1 and weighs in at just 62 pounds. The Blue Lightning is about 80 pounds lighter (equals 20 less HP needed) than other popular belt drive reduction units on the market. Because of its tighter fore & aft dimension, it allows the engine to be mounted about 10” further aft in the airboat. Having the engine further aft materially reduces the previously explained “push down” effect on the airboat and allows more useful space ahead of the cage for driver and passengers.

I would choose an aluminum hull with an eight foot transom from gunnels tip to tip and sixteen feet long to mitigate the “push down” effect previously explained. The bottom should be of .190” plate and the sides of .125” plate formed to provide turning chines. I would have .250” black polymer skid protection on the airboat bottom.
The boat will be a four passenger setup with the driver station at the front left position to offset the normal right torque effect of the left hand rotation of the engine crank, belt drive and propeller. The one small main battery will be placed in the forward storage compartment under the bow deck to help offset the weight of the engine mounted slightly rearward utilizing the Blue Lightning Outdrive. At 4 pounds of boat per HP, a second battery robs about 12 HP from performance. (We will take along a several ounce cell phone instead.) A low flat gasoline tank will be mounted near the center of gravity of the boat so that fuel burn will not change the hydro-statics of the boat. Because the boat will be very fuel efficient as airboats go, it needs only a 30 gallon tank. 30 gallons weighs 180 pounds and requires about 45 HP to haul around.

I personally prefer to use polished stainless tubing to fabricate the motor stand, cage work and the seat structures of the airboat and would use this style. With an aluminum hull and stainless steel rigging the airboat will be nearly timeless and last for decades of use. I would use low mounted double aluminum rudders with the widest portion being placed at the bottom to keep the maximum turning force as near to the waterline as practical. My target empty weight of this quieter high performance airboat will be about 1600 pounds. With a maximum of 1600 pounds of thrust available, it will take a cabbage palm tree to stop it.


In summary, to build a four passenger, high performance, fuel efficient and quieter airboat that will meet the future noise rules one should;

• Build the lightest weight airboat that will deliver the performance desired.
• Use an 8’ wide transom and, say up to a 16’ hull for more planning area.
• Use the lightest weight engine that will produce the required 400 HP.
• Optimize and build the quietest exhaust system possible for that engine.
• Choose a propeller size to match the engine HP. (10.61 HP per disc sq. ft.)
• Choose a propeller brand and model that is near perfectly optimized.
• Use a light weight reduction unit that allows optimum propeller RPM.
• Design for the lowest Push-Point as is practical considering following wakes.
• Design for the lowest possible center of gravity for the airboat. The belt drive reduction unit allows a lower engine installation as compared to a typical gear drive reduction unit.
• And finally, with “tongue in cheek”, one should rig the throttle linkage such that when the high speed jets of the carburetor cut in at an advanced gas petal position, a continuous 100 volt electric shock is delivered to the seat bottom of the boat operator.
We built such a fuel efficient quieter 4 place airboat about 5 years ago. Frank Bagwell from Frost Proof, FL helped me with designing and building it. It used the ZZ-383 Stroker engine, the Blue Lightning Outdrive, an 82” propeller and was 8’ wide. Frank wanted a shorter boat so we made it a 13’ long boat. We built an exhaust system as described above. It was consistently below the 90 db as measured 50 feet from the boat and had excellent fuel efficiency. On the Lake Kissimmee chain of lakes, with excellent performance, Frank was able to run all weekend on a 30 gallon tank. His friends with aircraft engines had to refill daily burning about twice the more expensive gasoline than Frank did.



Frank won a couple of contests for quiet airboats and received some certificates of award for doing so. We later sold the boat and to my knowledge it is still in use in the Kissimmee area.
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Re: "Build a Fuel Efficient Four Passenger Quieter Airboat"

Post by watersports7 » Sun Nov 13, 2011 3:26 pm

Hats off to David Wine! EXCELLENT TECHNICAL ARTICLE :salute:
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Re: "Build a Fuel Efficient Four Passenger Quieter Airboat"

Post by bowhunterfl » Sun Nov 13, 2011 3:57 pm

That is a lot to take in but very good reading.
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Re: "Build a Fuel Efficient Four Passenger Quieter Airboat"

Post by Rich Andrews » Sun Nov 13, 2011 4:46 pm

i've read it 10x and still absorbing the info...
I'll have my Manatee burger medium please...just say NObama

14x8 deckover FELBER 397ci.. HP ???..just stay back!!

LOHA is AHOL backwards

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Re: "Build a Fuel Efficient Four Passenger Quieter Airboat"

Post by akblackdawg » Sun Nov 13, 2011 4:51 pm

Outstanding. If all goes well with selling my current boat this winter, I am planning to assemble a 16x8 boat this spring and will utalize the information in this article in my build. Thank you, Bud
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Re: "Build a Fuel Efficient Four Passenger Quieter Airboat"

Post by littlejoe » Sun Nov 13, 2011 8:27 pm

very usful info :thumbleft:

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Re: "Build a Fuel Efficient Four Passenger Quieter Airboat"

Post by gkielczewski » Sun Nov 13, 2011 8:44 pm

WOW My brain is still absorbing it all. Great article.

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Re: "Build a Fuel Efficient Four Passenger Quieter Airboat"

Post by plumcrazy » Sun Nov 13, 2011 9:21 pm

well end of story david built the boat and here it is. it worked as planed because i owned and operated it for several years and it was the quietest boat ive seen, i out ran a lot of boats and never stuck it it was the perfect car boat to me


THE FOX

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Re: "Build a Fuel Efficient Four Passenger Quieter Airboat"

Post by John C » Wed Jan 18, 2012 7:48 pm

Haven't seen that boat since the Bullfrog Bud run in the Glades. Every bit of what David and Plum said is true. That is one hell of a CM Boat. Plenty of power and very quiet.

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Re: "Build a Fuel Efficient Four Passenger Quieter Airboat"

Post by CarMotorBarge » Wed Jan 18, 2012 8:43 pm

Does anybody know how much this boat weighed? I know that David was shooting for 1600 lbs. Did he actually get that? Thanks.
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Re: "Build a Fuel Efficient Four Passenger Quieter Airboat"

Post by plumcrazy » Wed Jan 18, 2012 9:27 pm

it was under that

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Re: "Build a Fuel Efficient Four Passenger Quieter Airboat"

Post by heater17 » Wed Jan 18, 2012 9:32 pm

great reading, wish there where more pics of the boat

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Re: "Build a Fuel Efficient Four Passenger Quieter Airboat"

Post by edbass » Thu Jan 19, 2012 7:26 am

very intersting great airboat advise .. OK now what did all that say .. lol j/k love to learn new things my boat also is 16x8 and has a 383 stroker sounds alot like my boat .thanks for the good read keep boatin brothers .

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Re: "Build a Fuel Efficient Four Passenger Quieter Airboat"

Post by PeaRiverOpossum » Thu Jan 19, 2012 8:06 am

Very useful info...probably the most informative post I have ever read on here. :thumbleft: AND it seems to be backed with facts other than the usual opinions and "that's the way we've always done it mentality" that I hear so often. David, Thank you for taking the time to educate us. I know that little write up took some time. This is very useful info and I will definitely consider when I get to build my boat. I will be marking this post for future reference. NOW...Where are all the A/C guys that are going to dispute....Bueller?! :scratch:

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Re: "Build a Fuel Efficient Four Passenger Quieter Airboat"

Post by slow5ho » Thu Jan 19, 2012 8:18 am

i like the 100 volt shock to the driver as the secondary jets opened.
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Re: "Build a Fuel Efficient Four Passenger Quieter Airboat"

Post by Olf Art » Thu Jan 19, 2012 11:21 am

John C wrote:Haven't seen that boat since the Bullfrog Bud run in the Glades. Every bit of what David and Plum said is true. That is one hell of a CM Boat. Plenty of power and very quiet.
I love that boat. I remember Plum and his family sitting on it down at the launch site the morning of Bud's ride. When everybody fired up to follow Bud out to the crash site, I couldn't hear it from where I was standing.

When we had our Quiet Airboat Demo. at Loughman's in April,'06 this was the 2nd quietest boat there. If I remember right I think it blew around 82 db. at 50 ft. on plane. With one of the newer props available now like the Whisper Tip or the "Q" that boat could easily run sub-80 db. :glasses7:
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Re: "Build a Fuel Efficient Four Passenger Quieter Airboat"

Post by CarMotorBarge » Thu Jan 19, 2012 12:43 pm

Didn't WT win this competition by a wide margin? :lol: Just messing with the Water Thumper haters. On a serious note, I would like to say thanks to WT and David Wine for advancing airboat technology. This is great for the future of airboating.
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Re: "Build a Fuel Efficient Four Passenger Quieter Airboat"

Post by Olf Art » Thu Jan 19, 2012 12:53 pm

Thunder did win it ..... his rig blew 77.3 db. at 50'. That boat was not only spooky quiet, but it was fast too.
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Re: "Build a Fuel Efficient Four Passenger Quieter Airboat"

Post by plumcrazy » Thu Jan 19, 2012 1:04 pm

wt won a club test, but he wasent a part of the test by fla atlantic university and the fwc it was a more stringent controled a documented test with calabrated sound equipment, i have a certified doucument on the fox boat of 82 at 50 ft with the boat set up as you would run it . the thunder sled was crazy quiet during the competition he won. but in my oppinion it wasent pitched and tuned like he ran it . and a foot note the fox boat had a 2 blade 82 serius during the fau test/ when i had it it had 1 more blade and was quieter, i could plain out in deep water and have a normal conversation

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Re: "Build a Fuel Efficient Four Passenger Quieter Airboat"

Post by Tony480 » Thu Jan 19, 2012 1:20 pm

Finally someone see's it. That WT boat was not set up how it would be run. And didn't Steve jurnigans boat home in second? It was the turbo charged 4 cylinder. I believe it only lost because he was running a 3 blade h series. That boat was exactly the way it was then as it is now. Except now it has an NGH.

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Re: "Build a Fuel Efficient Four Passenger Quieter Airboat"

Post by T. Gaffney » Thu Jan 19, 2012 1:23 pm

Now that I think about it, we should give credit where it is due for advancement in airboat noise.

Thank you David Whine for inventing the wide blade, composite, low rpm propeller.

Thank you Sensenich for trying to improve on this design.

Thank you Rotator and Stinger for developing the gear ratios to really take advantage of these propellers.

Panther for the counter rotator which was the first "quiet" airboat.

Not taking anything from WT and his engine building but he definitley was not part of the group that is responsible for the advancements we enjoy today...

Not being a hater either. I just think it should be kept straight so the people that deserve the credit are acknowledged.
Last edited by T. Gaffney on Thu Jan 19, 2012 4:32 pm, edited 1 time in total.

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Re: "Build a Fuel Efficient Four Passenger Quieter Airboat"

Post by akblackdawg » Thu Jan 19, 2012 1:30 pm

I would say, from my observations, Dave should be given credit for the man who really advanced and let people know the advantages of the lower, 2.68 ratio. Bud
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Re: "Build a Fuel Efficient Four Passenger Quieter Airboat"

Post by T. Gaffney » Thu Jan 19, 2012 1:41 pm

akblackdawg wrote:I would say, from my observations, Dave should be given credit for the man who really advanced and let people know the advantages of the lower, 2.68 ratio. Bud
You are correct sir. He is definitley the one who invaded the internet with the 2.68 ratio. Do you think the people who developed it did it by accident though?

CarMotorBarge
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Re: "Build a Fuel Efficient Four Passenger Quieter Airboat"

Post by CarMotorBarge » Thu Jan 19, 2012 1:47 pm

And thank you to WT for doing the RnD to put all of these components along with the LS engines into a package that maximizes prop efficiency and minimizes noise. Sounds like we are just 1 big happy community. :lol:
14x7.5 Al David hull with 14 inch transom
419 CI Horsepower Barn LS3 with 2.88 Ox Box swinging 4 blade 83.5" R
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Olf Art
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Re: "Build a Fuel Efficient Four Passenger Quieter Airboat"

Post by Olf Art » Thu Jan 19, 2012 1:59 pm

T. Gaffney wrote:
akblackdawg wrote:I would say, from my observations, Dave should be given credit for the man who really advanced and let people know the advantages of the lower, 2.68 ratio. Bud
You are correct sir. He is definitley the one who invaded the internet with the 2.68 ratio. Do you think the people who developed it did it by accident though?
I'm done with this crap. This is like saying John Force won at Pomona, but he had to use a different set-up to win the Gator Nationals!! What ??
The whole point is that David Wine is a genius. He was/is a pioneer in airboat sound and performance. He comissioned and built an awesome boat to show all of us he was willing to put his money where his mouth is, and he succeeded. He not only built the boat, but he designed and manufactured the Blue Lightning belt drive that it wore, not a gearbox!

Please stop thowing dirt on the whole purpose of this thread ..... to recognize Mr. Wine for his genius. His accomplishments are many and very important to those of us who really give a damn about building quiet boats that will perform too.
"I know not what tomorrow may bring, but I know Who brings tomorrow."
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