Thanks for the heads-up Murph
Any pics of 'Spirit Of Australia' you have would be much appreciated.
And if there are any underside pics around of Ken's second boat (Australian Spirit), that would be a bonus.
From the feedback I've been getting on other threads, there's a lot of suggestions to build a long and skinny BlueBird K7 type shell. Others have suggested taking a standard 3-point prop design and putting a Turbine on it.
Neither of those approaches particularly appeal to me - so I'm building a design based on a modified version of Australian Spirit (boat #2). Like you, I'm not sure how well it will scale down, but most model aircraft seem to scale ok, so I can't really see why a boat shouldn't do the same. I guess time will tell.
I've made a bit of a compromise in my design - Ken's boats run a length:width ratio of around 3:1. I'm aiming for a boat around 2m long - so in theory it should only be around 600mm wide. But I want to run my Twin Turbines on it, so I've gone for a width at transom of 750mm, with a max of 900mm where the front sponsons start. Hopefully, that's not too wide and it doesn't turn into a 'wing', but that's the road I'm travelling down at the moment - mainly due to the distinct lack of info on RC Jet Thrust boats. And by that I mean real Jet Thrust boats, not prop boats modified to accept a Turbine engine.
The reason I've picked Kens designs as a basis is that they have been proven as successful - for over 30 years now no-one has come up with anything better. Sure, lots of hoo-ha and talk, but other than himself, no-one else beaten his record. So that says something to me.
While I'm not out to set or break any RC records, I've been captivated by the subject and I'm totally hooked on RC Turbines. I've received a lot of negative input around the traps, and what really bugs me is that not one of those people have built and tested a Jet Thrust boat. You will have seen first-hand that his design varies markedly with the other designs of the past and present. Designs that, in the past, have proven fatally flawed, and 'current' designs that have been all-talk-no-action for almost 10 years now.
Unfortunately, we never got to see Ken's second boat run in anger - only a few shake-down runs at Taree etc. He built that boat with 600kmh in mind. I've read that he was also working on a third boat, with a mooted ceiling of around 800kmh. Ken is 71 now, and I don't think we'll see him running any of his designs himself any more, should someone finally break his 317mph/511kmh record set way on back in 1978. His two main rivals - Arfons and Taylor - sadly succumbed to the temptation of joining the most elite club on the Planet of which Ken Warby is the only member: To have officially recorded a World Water Speed Record of faster than 300mph on water, and lived to tell the tale.
Will my boat work? Who knows. What if it doesn't? Who cares.
But at least I'll be in a position to say to myself "This bit worked...this bit needs improving..."
And I'm getting quite a buzz from the whole process.
Here's a coupla pics of where I'm at at the moment...
Cheers,
BJ
