Can there be electric offshore race boats?

[Ratickle]

Do you think the overdrive transmission with the V-Drive is a good thing to get the boat to speed? Or is it just added weight that's not needed?

I'm sure I can find out what happened to that boat.

And it was a Skater that Tom was building. Set in front of the shop for a couple years before he bought the eliminator.....

I called it another of his defying death boats.....

[gearhead]

Lorhing
If you are really going to do this I would be honored to help in any way.

I don't know what level you want to set but it sounds like it will be pretty high. I am sure I would be an asset to your teem.

[Ratickle]

If this is something that we really want to persue, it looks as if the number one issue is attracting the interest to get the cells donated, or loaned?

[lohring]

I worked with Enerland for our boat's batteries. The batteries still cost $14,000. Since they have been bought by A123, You would need to start all over. Battery charging is also an issue. We used standard model boat chargers that could charge two batteries each. That took 21 chargers at around $100 each with a special discount for all the batteries in our boat. Custom chargers may be available but that would need to be investigated. Money is the biggest issue, and I'm not interested in financing anything like this.

We ran a quick change gear box with standard differential quick change gears to match motor rpm to the propeller. Gears are lots less expensive than propellers and it would take a custom design to run a propeller with a 4-5,000 rpm brushed motor. The prop we ran turned around 8,000 rpm. Brushless motors aren't as limited, but some way to match motors to propellers would be good. It also would be lower drag to run one propeller with the two motors. There may be synchronizing issues. We could avoid these problems with brushed motors and existing Zilla 2000 amp controllers like what we ran. Manzanta makes the Zilla and has batteries and chargers as well. Brushed motors would be less efficient and might need more batteries. It would cost a lot less. Mike builds differentials for a living, so that's a possible source for a gear box. Below are some pictures of the boat and a graph of the data from the record runs. This proposed boat would be a much bigger project.

Lohring Miller

[Hellbent]

Money is the biggest issue, and I'm not interested in financing anything like this.

Sounds like a good college engineering project....

[T2x]

Sounds like a good college engineering project....

Colleges already waste too much money on meaningless "projects". Also, they would probably try and link the effort to some federally funded study on the sex drives of goats (as a precursor to giving farm animals the right to vote) .

This is the kind of thing that requires simple patience in waiting for technology to catch up to a need. Lohring has already proven that fast electric speed boats are feasible (as has the R/C community) and "Offshore" speed records are largely window dressing in a sport that should be more focused on long distance endurance in big seas. The fact that an ultralight cat in calm water can do this or that IMHO has little in common with the true foundation of Offshore racing.

[T2x]

I worked with Enerland for our boat's batteries. The batteries still cost $14,000. Since they have been bought by A123, You would need to start all over. Battery charging is also an issue. We used standard model boat chargers that could charge two batteries each. That took 21 chargers at around $100 each with a special discount for all the batteries in our boat. Custom chargers may be available but that would need to be investigated. Money is the biggest issue, and I'm not interested in financing anything like this.

We ran a quick change gear box with standard differential quick change gears to match motor rpm to the propeller. Gears are lots less expensive than propellers and it would take a custom design to run a propeller with a 4-5,000 rpm brushed motor. The prop we ran turned around 8,000 rpm. Brushless motors aren't as limited, but some way to match motors to propellers would be good. It also would be lower drag to run one propeller with the two motors. There may be synchronizing issues. We could avoid these problems with brushed motors and existing Zilla 2000 amp controllers like what we ran. Manzanta makes the Zilla and has batteries and chargers as well. Brushed motors would be less efficient and might need more batteries. It would cost a lot less. Mike builds differentials for a living, so that's a possible source for a gear box. Below are some pictures of the boat and a graph of the data from the record runs. This proposed boat would be a much bigger project.

Lohring Miller

In reviewing your project I have a question. Why you didn't go with a simpler inboard installation rather than add all the weight for an OB center section and lower unit? Did you feel that trim and prop height needed all that much adjustment?.

Thanks,

[lohring]

Our original design for a lead acid powered boat was an inboard. Here we felt we needed to fly a heavy boat so the design below was modeled in 1/4 scale for testing. When lithium polymer batteries were allowed, we realized we had a power plant that would fit in an existing 80+ mph design that happened to be an outboard. There was a lot of outboard design expertise in our area as well. Ron Jones already had sponson molds for the design, and Bob Wartinger's prop was the difference between 80 and 100 mph. We pushed the boat well past its design speed and there were stability issues. If we were to revisit the record, we would probably go with an inboard hydro design like the 1.5 liter hydros. Capsules are needed at these speeds as well.

Lohring Miller

[Ratickle]

That's an interesting design. You designed the lift to offset the weight of the batteries, cool. Did you get a chance to test it in a tunnel?

When we were running the 1/4 scale unlimiteds in nitro we did a design with an automatic adjustable canard wing controlled by a RC helicopter gyro. It was ruled illegal almost immediately, but it sure worked sweet once dialed in to stop blowovers....

We did get to test several designs in the wind tunnel at Western University in Kalamazoo. Finally built one with zero positive or negative lift (well almost)....

[Anchored]

Lohring,

Have you looked in to PM AC motors with vector drives?
Some timed out F1 KERS stuff may be the hot ticket to get more efficiency.

Jeff

[lohring]

We ran several versions of Mike's design to set model boat records. Wings in ground effect are an excellent way to reduce water drag. Unfortunately, the rougher it gets the poorer they work. I'm afraid hydro style boats will never be able to run in offshore conditions. Cats are the only successful lifting offshore designs so far.

I've pretty much gone back to model boats. It's lots easier to try new ideas in both propulsion and hull design.

Lohring Miller

[keith2500hd]

the bad part is the weight does not fall off, similar to burning off fuel. the batteries will require cooling to control heat from high discharge rate. motor may require cooling also. electric operation, charging system is dangerous if overcharged, so include monitoring equipment. the SWATH was considered best design for drive setup, move heavy weight to submerged hull. salt water and batteries don't play good together also, sudden high current discharge rates(boom) and chloride gases. battery source is the limitaion for electric drives, weight, sustainable cycling and large capacity to weight %. if you look at cars that have high performance factors, they are sub 3000lbs. tesla rodster or porsche 356 speedster as examples.

[Cookee]

6 months is a very long time in battery design and manufacture - everything is getting more reliable, cheaper and lighter so I can definitely see a time where battery power would be available for powerboats, however recharging will remain an issue for a very long time unless you have on board recharging!

Another option would be something like fusion (I think?) powered boats, they already have small prototype generators I believe.

[Ratickle]

Our original design for a lead acid powered boat was an inboard. Here we felt we needed to fly a heavy boat so the design below was modeled in 1/4 scale for testing. When lithium polymer batteries were allowed, we realized we had a power plant that would fit in an existing 80+ mph design that happened to be an outboard. There was a lot of outboard design expertise in our area as well. Ron Jones already had sponson molds for the design, and Bob Wartinger's prop was the difference between 80 and 100 mph. We pushed the boat well past its design speed and there were stability issues. If we were to revisit the record, we would probably go with an inboard hydro design like the 1.5 liter hydros. Capsules are needed at these speeds as well.

Lohring Miller

There are a few of those around the east side of this state to start with.....

[lohring]

There's been some progress in this area since the thread was started. A realistic looking electric outboard package has been developed. It can go 45 knots (51 mph). Note that duration isn't mentioned. However, take a careful look at the power plant price in the brochure at the bottom of the page. Note also the British unlimited electric inboard electric speed record boat at a blazing 32+ mph with 135 hp. We ran around 90 hp for a 99 mph record with some very serious restrictions on voltage and motors. We didn't need to run very long, though. That's the difference between a high drag hull you could run offshore and a hydroplane under ideal conditions running a very few kilometers.

Lohring Miller

[Bobcat]

This is interesting also.



http://www.youtube.com/watch?feature...&v=fpNej1Q35ow

[old377guy]

I wonder what the run time is for that