Danny,
Thanks for this.
I've played with some wacky designs before - and it was the "must be like a full sized ship" rule that seemed to the the issue with racing in ORMA - which is my preference as so many people here race in ORMA. There was a discussion about it a while ago and the concensus was "development" comes from things like engines and prop designs, rather than actual boats. However, the bat wing boat makes a good example here: how does it fit into the "2 inches of free board" rule and also, there are no current full sized racing boats competeing that use such"bat like" protrusions - although there are prototypes.
As background to what we are thinking, before I started building EarthRace, I decided I wanted to build the fastest, most futeristic boat possible. In a way, Earthrace fills this brief - it's like a Grand Touring motorcar - won't win all the races, but there will be no faster way to drive from the UK to Spain in one long session. To go with EarthRace, I want to build a racing boat that will be as fast as physics and design will let it.
I did a lot of reading, and joined a lot of full sized boat design forums when I was researching a boat to build before EarthRace. There is a growing consensus on these forums that racing boat design ( full size racing boats) has got stuck in a rut. The sport has settled on a few designs which are Good, but there is better out there. For example, there is $millions spent on evolving a deep V a fraction on from what is currently best of breed, but there are vast numbers of concepts which have never been really looked at. And now that hydrodynamics is feasible for the hobbyest to play with on a home computer, a lot of these designs which have come about since the 1930's become feasible to test and play with.
This "bug" has also caught a friend of mine and myself. He supplies the cunning plans (lots of them... of which about 1 in 10 are physically possible :( ) and I then work out what can be done with them and if I could make such a thing out of GRP
The three area's we've been looking at are:
1) Aerodynamics - there seems to be a distinct lack of them currently. Look at a z-class boat straight on - it's just like a brick as far as Areo is concerned. Areo packages could be used to increase lifting of the hull from the water, to provide stability in turns or to be able to cope with wave chop and still allow for flat out speeds ( although this one is more difficult as it would need dynamic responses - but the model plane guys are already doing this stuff day in day out ). In model boats, there is also the ability to use aero components to act as a passive super charger for the engine - but I have no idea how you could tune an engine where it's sweet spot is designed to only occur when it's flat out in the middle of a lake..
2) wake-shaping. There is energy in the wake that comes from water being moved by the body of a boat. Rather than waste this energy, the hull can be shaped to allow it some of this energy to be re-claimed into either forwards speed or to counter tipping during turning to allow tighter turns ( or both, but we've not worked that one out yet )
3) reducing water/hull contact and/or friction. There is lots that can be done here. Some of it only practical on a model sized boat. There are those odd Air scoop hulls at full size, but I can see those flipping up alarmingly when made as a model and going at speed. A few examples would be to alter this design ( have LOTS of small air scoops - like a deep V but with 20 scallops down each side - makes for really stable turns as well ), create bubbles under the hull without interfering with the prop (that ones easy - just add lots of 1mm protusions - thin wire or pins would be perfect -sticking out from on the centre line the hull. That way the boats body is racing through an air carpet, but the prop is biting "real" water - and when you corner, the hulls hits real water and you have no alteration in cornering ability )
There are loads of other concepts out there - rapidly moving ballast during turns, changing the actual shape of the hull itself etc,. that are all possible at model sizes that are less possible with full sized.
A great example is one I was reading recently: Whats the perfect shape for a racing boat? Answer is a shape like a scaled up Broad bean lying on it's flatter side. VBrilliant areo and hydrodynamic properties. In the case of a full sized boat, there are lots of issues with this shape ( where do you put the crew - how do they see - how do you make a flatish bottomed boat survive getting battered when it crashes back into the water etc etc ) - but I can knock on of thes up fairly easily, without any of these issues, in model boat sizes - no crew, small weight so won't break etc etc
As you can tell, some of these boats, if built, would look VERY odd, and I'm not sure the ORMA taking a shine to them - given that the person who won last years championship ( I think it was you yourself danny? - almost sure it was *someone* called Danny but I could be being thick again ) had abuse slung about them becuase of a free board which could, or could not, have been less than 2" in size.
How would they would react to a boat looking like a broad bean, with a group of areodynaimc wings and whatsits on the top, and rows of pins jutting out down the centre line - it would be interesting to watch
Most of these concepts will make for a fast boat if you shove a Zenoah engine in them, but unless they are raced against other boats, there is no base line to compare against to see if they are better or worse than another design.
Which comes back to my original question ( eventually ....
) these ideas are fun to play with in the pub and on the computer, but if I'm going to actually put time and effort into building one or more of them, I only see a point if the race boats can actually be raced.
So we're looking for a race series that has a "anything goes" catagory.
eek... this post is far to long and boring.
Danny, thanks again for the info. Sketches freely available - I will beg forgiveness for the awfulness of the drawings in advance as they will be my versions from the pub rather than his posh pictures, as they are on A2 and I have no way of getting them onto the site. No patents - 90% of the idea's were developed in the 30's and 40's anyway...
Steve
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Topic: Is there any "anything goes" racing series for model boats? (Read 2219 times)