The Aquacraft VS1 is an all-out competition tunnel hull designed by racer and Aquacraft engineer Mike "Grimracer" Zaborowski. The VS1 was created for the sole purpose of winning heat races and after weeks of testing at the pond, I totally agree with it's labeling. It's fast on the straights and hold the turns well. There are really no bad characteristics about the VS1 which makes it the ideal platform to put you into the winners circle.
The VS1 has the advantage of being a lighter hull than the competition without sacrificing durability. The end result is a faster, more nimble hull that will dominate the sport classes and hold it's own even against some modified boats.
This tunnel hull comes almost ready to run; the hull has been built and epoxied, the only things to do are install the radio box tray, the gas tank, install the outboard motor, and run the throttle and steering cables. A small bit of sanding may be required and we'll cover that later in the review. Now, lets open the box and have a look at the VS1 competition tunnel hull.
High performance Aquacraft Grimracer 40x52 3 blade prop
Cowl with flotation
The VS1 comes packaged well with styrofoam included to protect the bottom and stern. The tips of the sponsons are secured inside a cardboard box that provides adequate protection during shipping.
Even though this is an almost ready to run boat, there are a few areas that need to be addressed. The radio box is built and installed, but the interior servo tray needs to be fitted as well as the steering and throttle cable's plastic guide that attaches to the back of the box. The fuel tank is included but needs to be mounted. The tank tray comes as 4 separate pieces that are glued together, then attached with screws to the hull. You'll need to drill the holes in the transom for the outboard, and solder and attach the steering cables and throttle cable. Finally, you'll need to check to make sure the bottom of the boat is true. If it isn't, a little sanding is required. I will touch on all of this during the build portion of the review, lets get back to examining the hull.
The hull center section is made of a lightweight wood-over-foam construction and the sponsons are wood with internal braces. The finished product is coated in a glossy clear coat to prevent fuel and water damage. The finish of this tunnel is very professional and I was hard pressed to find any blemishes whatsoever.
Flip the boat over and you will see large stumble blocks at the front of the tunnel. Stumble blocks are found on almost all rc tunnel hulls and are designed to keep the boat from hooking, or spinning out, when sharp turns are made. They act as barriers to prevent the sponsons from dropping down too low in the water, almost like a ride pad of sorts. There are also two wood plates on the bottom of the tunnel; the front plate acts as a reinforced bottom for the radio box and the aft plate reinforces the transom where the outboard engine applies alot of force to the hull.
The 8oz. fuel tank mounts on a tray attached to the hull in front of the transom. The fuel tank is held to the tray with rubber rings. The rings hook to the tray's uprights and secure the tank, preventing it from sliding around. Because the tank isn't hard mounted, you can move it forward or back to adjust the VS1's center of gravity.
The VS1 steers with a pull/pull cable design just like a real tunnel hull. An included servo wheel attaches to the steering servo and holds the cables that run back to the engine. The engine side of the cables have adjusters to take up any slack. When setup with out any slack, the cables are just as strong as push rods and wont bend like a rod will when force is applied. The cables exit the box at the rear and are held in place by a plastic guide. This guide also holds the throttle cable and the on/off switch where they exit the back of the radio box. The tolerance between the cable and the housing are are so small that water does not pass through into the box. The act of switching the VS1's receiver on and off is made easy with a push rod that hooks onto the switch and runs the length of the hull where it exits out the back of the transom. This allows you to turn the receiver on and off with the cowl on.
OS .21 XM mounted
Fuel tank in place
Installing the cable guide
Fuel tank mount before installation
The engine recommended by Aquacraft is the OS .21 XM outboard. The VS1 was designed to use the .21 XM with the stock muffler, not a tuned pipe. Even so, the boat is capable of speeds around 50mph with the stock engine, a good race prop, and fuel with at least 50% nitro content. At $349.98, the OS 21 XM outboard is by far the most expensive investment when purchasing the VS1. But, its one that will definitely pay off with performance and reliability for years to come. Think of it like a real boat; the engine is always the most expensive part!
The VS1's cowl is made of abs plastic and comes bare without decals except for a black windshield. A full decal sheet is included and has an additional windshield graphic with a more realistic look. Various Aquacraft and OS Engines decals are also on the sheet and give you plenty of options when it come to customizing your VS1. The cowl attaches to the hull with two nylon screws at the rear and a lip that slides under the tunnel up front.
Aquacraft 40x52 3-blade
Steering cables, throttle cable, and on/off switch exit
I will start from the beginning and briefly cover what it takes to ready the VS1 for it's maiden voyage. You must read the manual for detailed explanations of all the steps. There are a number of tools needed to complete the VS1. They are as follows:
Soldering iron outboard engine
Small phillips screwdriver
5-64 hex wrench
Needle nose pliers
Silicone sealer for nitro fuel
Rotary tool with cut-off wheel
The first step in assembly is to check the hull for any gaps in the seams. The boat is assembled well from the factory but it is still necessary to check. Run an exact-o blade around the seams and if it falls through, use some 2-part epoxy to fill the holes. You will also check the alignment of the sponsons at this point. They should both touch the table at the same places. If there is any difference in the sponson bottoms, lightly sand until they are the same. This is known as blueprinting the bottom.
Next, drill the transom for the engine with the included engine mount template found in the manual. This is a pretty simple procedure, just make sure to line up the template with the transom and tape it down so it doesn't move.
The third step is to install the cable output guide, servo tray, and servos. Begin by screwing down the cable output guide, then clamping the steering wire between the servo wheel. Next, install the servo tray and screw down the on/off switch and the servos.
To install the engine, place the motor against the back of the transom and set the included metal backing plate on the inside of the transom. Use the 6-32 bolts and washers to secure the motor. The metal backing plate is tapped so there is no need for lock nuts.
To assemble the fuel tank mount, use 12-minute epoxy and assemble the mount, which consists of 4 wood pieces, per the instructions in the manual. Next, screw down the tank mount using the 2x 10mm wood screws provided. Place the tank on the mount and secure it with the rubber o-rings.
To install the steering cable system, attach the cable wheel to the servo and run the cables out the back of the radio box through the plastic guide. Attach the threaded couplers to the engine's tiller arm, then place a mark on the cable to show you where to cut. After you cut the cable, solder it in the threaded coupler. Refer to the instructions for detailed pictures of the process. Next, install the throttle cable per the instructions and set up your servo throws. This is where the Futaba 4PK comes in handy with precise servo end point adjustment, trim, and dual rate settings.
At this point, you can either leave your cowl white or paint it to your liking. The manual contains two sections on painting; quick and easy, and professional finish. I chose to leave my hull white and applied some decals to my liking.
Now that the VS1 has been fully assembled, take the time to read the care and maintenance, hull tuning tips, and racing tips to help dial in your boat. Remember, nothing beats testing when it comes to getting it ready for racing.
The VS1 handles very well for a small nitro tunnel, but it's still a small nitro tunnel! If your used to running nitro mono's or larger gas boats, you've got to tailor your driving style to this tunnel and forget what you know about the rest. First, calm water is the key to consistent performance. If the water is choppy or windy, you can expect to flip the VS1 if your driving it wide open on the straights and powering through the turns. Like I said before, the VS1 is a lightweight hull and is more sensitive to wind and chop than other style hulls.
When driving the VS1, you want it to fly down the straights with a slight nose high attitude. This gets the wind under the tunnel, lifts the boat out of the water, and reduces the contact with the surface which in turn makes the boat go faster. But there is a fine line between nose up and too far up. The VS1 will flip back if it's got too much of the bottom of the hull showing, but a little practice makes it easy to determine that perfect ride attitude.
When you enter the turn, you want the boat to sweep it easily and not dig in hard. Setting the steering end points so there is less angle in the turn helps keep the hull upright. Basically, you want to get the boat dialed in to turn a few feet off the buoys at half throttle. Then run the boat wide open and add in more dual rate until it runs the course smooth and fast. Once she is set up to run this way, add a few more clicks for a faster reaction incase you need to maneuver quickly due to trouble.
In order to get your VS1 to run fast and stable, dedicate some time at the pond to test and tune. This means trying different prop shaft angles, outboard height adjustments, prop adjustments, and center of gravity changes. I ended up with 3.5 ounces of stick-on lead in front of the radio box and a 40x52/3 propeller that I sharpened, balanced, and cupped the tips slightly. Luckily, the manual has a basic setup parameter sheet that gives you key starting points should you get too far off from what works.
Once you get the VS1 setup to your liking, expect fast running down the straights and no bad tendencies when turning. I've got mine to where I can usually turn sharp running wide open but I like to blip the throttle before I enter the turn to get the nose down and avoid flipping. The pictures below show a good ride attitude with the nose lifted down the straights. Also, watch the video and you can see when the VS1 is turning well and when too much deflection was given at high speed, causing the hull to trip a little in the turn.
Running a tunnel, in my opinion, is more gratifying than running any other type of boat. It requires more attention while driving, its more sensitive to a proper setup than most hulls, and just looks so much cooler flying past you with only the tips of the sponsons touching the water.
In closing, I'll say the VS1 is a true performer in it's class. It's light weight, has great lines, and has zero issues with handling. In my first race in the class, B Tunnel, I took second place in a field full of modified hulls. I have raced gas boats before but this was my first time racing nitro boats and my very first tunnel hull. I'd say the VS1 is a great beginners boat because of its entry level price, it's ease of setup, and gentle handling characteristics. On the other end, the VS1 is the perfect racing platform due to its speed with a stock outboard.
If you've found yourself interested in the tunnel classes, buy yourself an Aquacraft VS1 and find out for yourself how much fun it really is.
Models/ Great Planes Model Distributors P.O.
Champaign, IL 61826-9021
Web Site: www.aquacraftmodels.com
The comments, observations and conclusions made in this review are solely with respect to the particular item the editor reviewed and may not apply generally to similar products by the manufacturer. We cannot be responsible for any manufacturer defects in workmanship or other deficiencies in products like the one featured in the review.