Low power semi-hydrofoil?

Perhaps they hope it will be a "fun" competition.

 

Perhaps they'll make a separate foil division!!

 

TBH, the organisers have asked all this years competitors for ideas and constructive criticism so that they can make the event even better next year. I think one of the challenges they face is keeping entrants motivated for the fun element, like the drill-powered, flapping fin semi-submersible "shark" and the amphibious paddle boat trike powered by six drills that we had this year, whilst also demonstrating the performance that a boat driven by cordless tools can achieve.

The sponsors (Makita) would probably want to see something that reflects the performance aspect, as it makes for good advertising for them, but the fun machines are a real crowd-pleaser, too.

My suggestion is that they split the event into a fun boat class and a race boat class, with the rules for the latter being published as soon as possible. There are already signs of power escalation that might need to be capped, though, rather like F1. The winner was running four Makita drills coupled to a common shaft, and several entries used two or more drills. Personally I think it'd be nice to see a rule such as not more than two, or maybe even just one, power tool, as that would make the focus on optimising the whole boat and propulsion system design.

If nothing else, I think my inverted T foil experiment will give some useful data that I can, hopefully, use for next year's entry, even if I don't end up using the same boat.

 

The previous discussion about the speed at which the T-foil potentially becomes effective illustrates the desirability of a "deployable" foil, where it is retracted when rounding the turn mark and accelerating and deployed when you reach appreciable wave drag speeds.
Probably needless complication for a fun competition but other reports of foiled boats always illustrate the excess drag penalty at low speeds. The obvious conclusion it to not have them in the water where a hull alone is more effective.
The non obvious issue is how to mechanize such an arrangement.

This is a great thread with some really interesting ideas.

 

Good idea about making the foil easily retractable. For the initial experiment I'm planning on fitting the inverted T foil to the small transom, so I think I could probably arrange a means of lifting it up clear of the water without too much difficulty.

 

Jeremy, here is a system used on the ORMA 60 Geant-they were trying a t-foil on the ama and the system used on Hydroptere.ch and the 59' Hydroptere:

click on image for best detail-stare at the Geant system a bit -its kind of hard to make out-Also-just did a rough sketch of another idea-

 

Six top line cordless drills sounds more like an "open" or "modified" event than a "fun" event. This is getting very expensive and they should decide now if they want a "fun" class, which should be one drill and perhaps a weight minimum; operator plus boat (jockeys carry ballast). We would find out who has the best displacement hull or maybe who has the best battery pack They could try to run a "box stock" class (a certain Makita drill model) but then they will need a tech department to disassemble the winners drill and battery pack to check for upgrades. Maybe just leave it an "unlimited" event; an even dozen drills should get up on plane Seriously, I hope they let you know what the rules are soon, seems to me it would be in their best interest too. This will be fun to watch, please keep us informed.

Jim

 

Indeed Jeremy, a great thread. Keep us posted!