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This past Saturday we left very early in the morning, trailered the boat to a local boat ramp, and launched the boat. The purpose of the test was basically to shake down the boat and resolve any final issues, and also to familiarize ourselves with the performance and handling of the boat. Right now we have a prop on the boat which was basically picked at random, and the prop size is way off, so we weren't going for speed today. However, an analysis of our running with this prop will allow us to establish a baseline from which we can begin spec'ing out a prop.
The boat ran almost perfectly today, aside from two very minor glitches. We ran for approximately 1.5 hours starting with the saddle tanks and the belly tank full, and nothing in the bow tank. We consumed approximately 50 gallons of fuel running around the bay in that time period. After some running we began experimenting with the trim and the X-dimension to see what effect it had on the handling of the boat. Then we started to push for slightly higher speeds to see what the boat could do with the prop we had on. We only managed a top speed of 65 mph on the day but that is because the prop is all wrong. Basically, the prop is too big because it was designed to run at, say 4,500 rpm, where our gearing is set to turn a prop at 6,000 rpm. So, the prop we need has to be a lot smaller. Basically what's happening is the prop is loading the engine to the point where N2 is being dragged way down into the 30% range. This is not allowing the N2 governor to kick in and control engine speed. As a result, we have to manually control the throttle to keep N1 from overspeeding, and we are holding back power quite a bit. If we were to advance the throttle any more, the boat would go faster but we would also overspeed N1 and damage the engine.
Now that we have established a baseline, we will start to look for a prop that will spin up to 6,000 rpm and allow the engine to operate in its proper speed range. The boat feels like it has a tremendous power potential, but currently we have to hold the boat back to not damage the turbine. The right prop will make a huge difference, and I think 100 mph will be very easy to acheive.
1/11/09- While the turbine boat has been stored away at MRD Performance, the guys have been performing some finishing touches. Eric has mocked up for a heat blanket that will surround the engine and keep the engine compartment from getting too hot when the hatch is on. This will also be aided by assuring cool airflow is directed through the engine compartment through the scoop on the top of the hatch.
The hatch has now also been completed, with a large stainless steel outer pipe which sits around the engine's tailpipe. The dual pipe system will allow for engine compartment airflow to pass through, keeping the engine compartment cooler and keeping the outer pipe cool to the touch, even when the engine is running.
Here are a couple of recent photos of the hatch and the boat. Notice that the boat has the F-16 canopies on it. Also, in these pictures, the boat can be seen with the race fairing on over the cockpit, which would be used in a race situation. The race fairing covers the area over the rear seats, leaving only two usable seats, but a much more streamlined and aggressive looking profile.
All that's left to do now in the new boat season is to fix a couple of minor issues with the gauges and to dial in the right prop. Right now this will be the biggest challenge. (next entry)
9/26/08- Nearly five years into the project, we have finally taken the T58 turbine boat out on its first test run. Though we had our share of technical difficulties, the run was generally a success. The date of the first run was friday, September 19th, 2008, late afternoon. When I arrived at MRD the boat was on a trailer out in the boat yard. There was a very strong wind blowing from the east and the sun was low in the sky. We lowered the boat into the water, tied it up, and then Eric and I began to go through the procedures for the boat. The plan was that I would drive the boat while Eric and our friend Marty would keep an eye on everything inside the boat. Pete from MRD would follow in a chase boat to give us a hand if we needed it.
After about 15 minutes of going over everything, I made the first start attempt. The engine spooled up nicely but then I got the signal from the dock to abort, so I shut down. The transmission was inadvertently left in reverse, so the boat started to move as the engine spooled up. The crash box linkage has very little travel between neutral and reverse. Note to self: add a neutral light on the dash.
The second start attempt followed immediately, but since the engine was still hot from the first start, I had to apply start derichment. I was a little overeager with the start derichment, and we had a hung start and aborted again.
After allowing some time to cool down, we made a third start attempt. This time, the engine spooled up and settled into a nice 60% idle. I was checking all of the instruments when we got the signal to abort from the dock again. There was an oil leak on the speed decreaser gearbox pressure line. We tightened up the fitting, and then went for the fourth start attempt.
The fourth start attempt was good, and we were ready to go. We untied the boat from the dock, I pressed on the shaft brake pedal, noticed N2 rpm drop to zero, but then before I could shift, it started to increase again. I lifted my foot off the brake pedal, but it was stuck to the floor. We shut down the engine, and noticed that the brake line fitting had cracked and broken off. The brake system was out of commission.
At this point I thought that our first test would have to end. However, Eric figured that if we could get a tow from the chase boat out into the bay, then we could start the engine in gear and at least run the boat, which is exactly what we did.
Once we were underway, I idled along for a little while, and checked all of the instruments. Even though N1 was at 60%, the boat moved along slowly without producing much of a wake, which will be important when it is time to maneuver the boat around the docks. The engine was running rock solid, and everthing seemed to check out, so I gave it a little throttle. I was amazed at how responsive the turbine was, even from idle, and how even a small change in engine rpm would accelerate the boat very strongly. I gave it a little more power to get the boat on plane, and then backed the throttle off to only about 1/4. Even at 1/4 throttle, the boat was moving along smoothly and quickly, and the chase boat, which tops out at around 45 mph, could not keep up any longer. We never actually checked our speed that day, but I estimate that we were cruising between 50 and 60 mph and never went above 1/4 throttle, except momentarily when accelerating to get on plane.
We made about five or six passes up and down the channel in the Great South Bay. In one direction the sun was directly in our eyes, while in the opposite direction the wind was blowing right in our faces, so the conditions were far from ideal. We played with the trim a little and the X-dimension, but did not get any conclusive information. Also, the prop was just a guess and we didn't really get much feedback on prop selection. There was considerable torque effect on the hull from the single engine, but I was really impressed by how well the Y2K-30 hull handled the rough water, and how nimble and stable it felt. The boat, which seems huge inside of a garage, seemed to shrink around me as I was driving it, and it felt like a little sportscar, very nimble and responsive.
While we were running, we had some electrical problems, and some of the engine instruments would glitch on and off, but generally, I was very pleased with the way the boat performed on this first test. I was particularly impressed with the handling of the boat, and even more so the responsiveness and feeling of power from the T58 engine. It really felt as if there was a limitless reserve of power that was just waiting to be unleashed.
After making a few runs, we decided to call it a day. We idled into the canal where the chase boat picked us up and towed us back to the slip.
Despite a few technical problems, the first run was better than we expected in many ways. I have to admit when I first started going I was a little bit terrified, but I found myself starting to get comfortble with the boat very quickly.
The next step is to get the electrical issues sorted out, fix the brake system with upgraded stainless steel fittings instead of aluminum, and straighten out some of the other minor issues. Then we will try to run the boat at least a couple more times before the weather gets too cold.
Then, the boat will go back to Superboat to get the finishes done, like the canopies, the engine hatch, and the rear seats over the winter. Next season we will get into hardcore prop testing and dialing in the boat for maximum performance.
Although we were very busy in the boat during the first test, Eric did have the presence of mind to shoot about 1 minute of video of the boat in action. Click here to see the video clip.
There's still a lot of work to be done, but I am really happy that the first run was generally a success. (next entry)
6/15/08- With MRD getting back into full swing on the rigging after a busy start to the boating season, we have 95% of the wiring finished, 90% of the plumbing finished, and we are going to test fit the exhaust stack onto the boat. I don't like making time predictions, because they never seem to work out, but we are very close to some test runs.
The pictures show the left panel instrumention in place. The left panel is basically the fuel management panel. It features four fuel level gauges for the four fuel tanks, and switches to transfer fuel from the three auxiliary tanks to the main tank. Above the fuel gauges are three gauges: Fuel pressure, water pressure (for the water cooling circuit), and voltage. Finishing up some touches on the helm panel, and we are getting very close to launching the beast. (next entry)
Batteries, switches, and solenoids in place. Wiring and plumbing complete. The stainless steel lines on the PT housing are vent lines from the oil tanks
The helm is almost finished and the throttle and shift levers are in place
A better shot of the throttle and shift lever. The picture in the middle is how you set the levers when you want to go really fast. Electrical panel just behind the helm.
More rigging. Note the Nye Soft Start Solenoid mounted in the middle picture
A good shot of the Nye Afterburner Control block, as well as the trim indicator sensors for the drive trim and X-dimension. The afterburner basically has a master on/off switch, as well as a fuel flow and streak control. The fuel is injected into the tailpipe, and is ignited by the streak, which is a burst of fuel injected into the outer combustor, which ignites when it contacts the hot turbine wheel. The streak is on a timer so that it does not run continuously. The afterburner does not add any performance but should provide a pretty spectacular flame show.
Batteries and main switches mounted under the rear seats
Shown on the left is the Holley fuel boost pump, fuel filter, and Nye fuel de-aerator
Brake pedal mounted in position with master cylinder and reservoir hidden out of sight
SDG and turbine oil tanks painted in their final colors, to be mounted in the engine compartment
As the pictures show, most of the plumbing for the fuel system, lubricating systems, water cooling system, trim and power steering, and hydraulic N2 brake have been completed, and now we are focusing on getting the wiring done. Like the previous turbine boat, this boat will have both 12 volt and 24 volt electrical systems running off the same batteries and sharing a common ground. 24 volts are used for the starter, igniter, the fuel de-richment solenoid, and the water pump, while the rest of the boat operates off of 12 volts. The alternator is 24V, and charges both batteries.
Once the wiring is complete, we will be ready to fire up the turbine for the first time in the boat. Once we find a prop to get started with, we will put the boat in the water for the maiden run and initial tests. While we are in the process of testing the boat and dialing in the prop, we will then work on putting the finishing trim touches on the boat. Initial water tests may only be about a month or two away, and I am hoping to get some preliminary video. (next entry)
Most of it is fairly standard rigging stuff so far, so I will let the pictures speak for themselves.
Stay tuned for more in the very near future. (next entry)
1/16/08- With almost 1 year passing by and very little being done on the project, there has been much frustration going on here. But finally, we are back on track, and I've got my fingers crossed for an April launch for water testing.
The reason why we lost so much time is that when we were ready to start rigging the boat, we began to notice that the T58 would not start on every attempt, and it seemed to get worse as time went by. Eric and I tried to troubleshoot the problem, but we couldn't figure it out. We sent the engine back out to Tim Arfons in Akron, and he finally ended up replacing the fuel control entirely, solving the problem. By the time we got the engine back, the summer was almost over and everyone had other commitments. Superboat was too busy with their production boats to have time to rig it, so the boat sat even longer. Finally, with the agreement of Superboat, we decided to use a local boat rigger to finish the rigging of the boat and get it ready for this spring.
The boat is now at MRD Performance Marine located in Lindenhurst, Long Island. MRD has an impressive facility and has a reputation for quality workmanship. Many of Superboat's custom boats have been rigged by MRD.
Pictures of the boat at MRD's shop. Here the gauges are being installed.
The updates should come more quickly now as we prepare to get this boat wet.(next entry)
2/11/07- In the last few weeks we have been working on getting all of the gauges and instrumentation that we will need to run the turbine boat. Once the gauges arrived, we met up to go over the exact orientation of the instruments. John from Superboat mocked up the instrument panel so that he could drill the holes in the dash.
The two pictures below show an overview of the helm with the primary engine gauges and switches. The gauges on the main panel will include the following:
-Two % rpm gauges for the N1 engine spool (gas producer) and the N2 engine spool (free power turbine), Measured Gas Temperature, Engine Oil Pressure, Engine Oil Temp, SDG Oil Pressure, SDG Oil Temp, Torque Pressure. Aside from the engine instrumentation, the main panel will house the hydraulic steering system, the GPS unit, and trim indicators for the tabs, outdrive trim, and outdrive X-dimension. Switches will include a master key switch, fuel boost pump, igniter switch, starter switch, fuel flow switch, and start derichment switch.
The picture below and left show a look at the face of the N1 %RPM gauge. 100% is equal to 26,500 rpm on the high speed spool. 100% N2 is 20,000 rpm at the power turbine, which equates to 6,000 rpm at the propeller. The picture on the lower right shows the mockup panel for the electronic GPS unit which will display speed, and below is a closeup of the trim indicator unit.
The port side helm will feature some of the gauges and switches that aren't essential to the direct operation of the engine. In the box there are four fuel gauges, one for each of the fuel tanks. The fuel boost pump will draw fuel out of the main fuel tank. The other three gauges will represent the two saddle tanks, and the front ballast tank. Switches under these other gauges will activate pumps that will direct fuel from the auxiliary tanks to the main tank, when the main tank is getting low. The two other gauges on this panel will be fuel pressure and water pressure, which will be the pressure of the raw water system that will be used to cool the engine oil.
The electrical system work is still a bit away, but I have made up a main electrical distribution panel that will take main 12 Volt and 24 Volt power and distibute it to all of the electrical loads on the boat. The pictures below show the main breaker panel, which will be mounted inside the cabin. (next entry)
1/13/07- With the holiday season behind us, we can get back into the boat, which is really coming along, and are trying to be ready for testing at the beginning of this boating season, around March or April.
In the past few weeks, we have been working in a couple of areas. We had a certified helicopter mechanic do a borescope inspection on the engine to assure that the engine was in perfect running condition. Everything looked perfect, except that we found that the thermocouple harness was bad, so we replaced it.
At the same time, Eric has been working fastidiously on the belt driven accessory drive. The accessory drive is driven from a v-pulley in the front of the output shaft brake which is driven off of the front of the Rolls Royce Speed Decreaser Gearbox at a maximum speed of 6,000 rpm. The 24V high amperage alternator is driven at a maximum speed of around 9,000 rpm by a v-belt and pulley. A second pulley runs across from the alternator to drive the power steering pump. A tensioner pulley takes the slack up.
John from Superboat, Eric, and I have been working on the instrument panel. After a consultation with Livorsi, we have modified the design of the panel based on the available gauge designs. We will have to have the torque gauge custom screened to read in percentage of maximum torque, and we will have to go back to two % rpm gauges, but I am still satisfied with the overall design of the panel. On the front panel will be the engine instruments and all the switches for the engine, while the auxiliary system switches will be on the side panel. Additional gauges for fuel and other items will be on the passenger side. Pictures to follow soon. (next entry)
12/03/06- On this boat, the front half of the 7 foot long engine sits in the cockpit, between the two rear seats, and covered by the front engine cover. Originally, this cover was designed to be removable in the event that the engine required service. When I saw how difficult it was to remove and replace the front cover, I knew that something had to change. After some discussion, we decided to hinge the front cover so that it could be easily raised. Rick from Superboat graciously put in the time to figure out the geometry on the gas struts, and the pictures below show how slick the new front cover really is. This setup is much better than the original removable cover, for a number of reasons. First of all, it allows easier access to the engine for basic maintenance and will allow me to perform compressor washes without having to rig up a remote water connection. But most importantly, now when I pull up to the gas dock to refuel, I can really show off what's under the hood.
The next big push will be to figure out the instruments and get the parts ordered. We will most likely be going with Livorsi gauges all around. This means that the turbine instrumentation will have to be custom made for this boat. Apart from the usual boat gauges, I will require a 6,000 rpm tachometer, a % N1 gauge, a turbine outlet temperature gauge, a torque gauge, and oil pressure and temperature gauges for the engine and speed decreaser. The boat will also have 4 fuel gauges, one for each tank. Updates to follow. (next entry)
11/19/06- At this point we have reached the final leg of the turbine boat project, which will consist of the final assembly and rigging of the boat, plumbing, wiring, etc., testing and adjusting the boat, and then putting the final finishes on it. Since the last update, much work has been done at Superboat. This update will cover that work.
The focus at this point was to finish the custom fiberglass work that was required mainly for the engine intake plumbing. The turbine must have a unrestricted source of cool, high volume airflow to the compressor.
The pictures above show the process of building the custom pieces for the intake ducting. A kevlar and fiberglass airbox will sit around the intake bell. The airbox is a prominent feature of the cockpit, as it will sit between the two rear passenger seats and can be used as an armrest. The airbox will receive fresh, cool air from two sources. The primary source will be an upward facing duct which is shown in these pictures. The duct will poke through the top of the engine hatch which will be finished with a forward facing scoop. The forward facing scoop will draw air in for the intake and will also allow some air to enter the engine compartment, to keep things cool in there. The second source of air to the airbox are the four NACA style scoops on the sides of the hull. Since the main scoop will be right next to the cockpit, I intend to use sound deadening in the intake ducting. Hopefully, the multiple air sources will reduce air velocity into scoop, which, combined with the sound deadening, should reduce the "vacuum cleaner" effect of the engine noise.
The above pictures show the general progress of the glass work of the hull. Notice that the engine hatch has been fitted and integrated with the air intake. Also you can see that the cockpit liner has been glassed to the hull, and that the cabin and engine compartment have been gelcoated. The hull construction is now complete.
Eric has taken the engine back to do the final adjustments. Once that it complete, it will be reinstalled into the hull, the outdrive will be reinstalled, and then we can begin to put the finishing touches on the boat. (next entry)
To see the previous part of this project, please click here
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