THE LAND SPEED POWER PLANT
“The wings are the only thing speeding us up. That's the engine.” explained Tim Meldrum, Emirates Team New Zealand Mechanical Engineer that has been in the middle of the Land Speed project from the start and explains the wing and how it works.
“Fundamentally, it's a wing section creating lift. It's very similar to an airplane or a glider. We use the flap on the tail wing (the big part hanging off the back of the main wing section) to change the main wing elements angle into the breeze to generate driving force.”
Otherwise known as trimming…
“So by having a tail wing at the back, that acts a bit like a weathervane. So as the wind direction changes slightly, it just automatically self-trims and maintains an angle to the wind.” The controlling tail wing is slightly off centre out of the main wing wake so its getting clean air to function efficiently.
So why not trim the wing like normal, with a main sheet?
“If we were to trim the wing with a conventional main sheet, it would take a lot of energy and a lot of focus from Glenn. We don't have stored energy on board, so with quite low energy input and without taking his hands off the steering wheel and concentrating on where he's going, he can very easily trim the wing using the tail flap”
The wing itself, manufactured by Southern Spars, is only 10m2, so that's smaller than the mainsail of an Olympic Finn dinghy. But how does a wing so small power such a large and heavy craft?
“Because we are going for a top speed world record, we have to optimize if for its top speed otherwise we will run into too much aero drag at the top end and fail to get the record. And we're only allowed a push start by human being, so we're trundling off pretty slowly to begin with, it is a long speed build.” Explained Meldrum
“It's all about trying to ramp your acceleration curve all the way up through the speed range and climb up over that existing record of 203 km's an hour. That sounds easy to keep accelerating like that, but with the way that we encounter increasing resistance every two or three kilometres gained, it's going to be harder and harder.”
“Richard Jenkins, the current world record holder did a very impressive job to put another 15 odd kilometres per hour on top of the previous record before his. And now from what we know, that that's a pretty big number in terms of a speed improvement, so it's going to be a really big mountain to climb to get above that 203 kilometres per hour mark. And it's not going to be easy.
While we've learned a bit in testing here in New Zealand, we haven't had the luxury of traveling at those top speeds yet. So there are a lot of unknowns out there for us to still discover with the wing and a number of factors, but we can’t wait to unleash Horonuku on the Lake and really let rip.”
