January 2013

                                             NEW KITE BUGGY SPEED RECORDS.

                                                     And a practical windpower/electric hybrid.          

On  the 6th March last year (yep, it's 2013 already), Brian Holgate set a new kite buggy speed record of 135.34 km/hr at Ivanpah dry lake (California) in the PL speed buggy and flying a Vapor.  (April 2012 Newsletter).

This is not just the buggy speed record, it's also the outright speed record for kite power.

And in my view (and I'm never wrong- except when I am), this is far below its potential maximum.

To go much faster than 135 with this buggy,  all that's required are fighter pilot level skills, suitably strong wind and for a few minor things not to happen- like lines not breaking and wheels not falling off.

Which will happen and not happen sooner or later - it's only a matter of time.

But I will be hugely embarrassed if it doesn't happen before the outright record is broken by either kite boarders (pretty unlikely), kite skiers (possible) or most likely, (and worst) by another buggy.

Not living within commuting distance of Ivanpah, there's not much I can do about this.

And Ivanpah is the  best place:

Not only is it big enough and flat enough, but often enough it has the strong winds which are required for setting wind powered speed records.  And Ivanpah is not a salt lake; the 'playa' surface there is uniquely suitable for resisting side load- a critical factor for wind power in contrast to engine powered speed records which are all about going straight ahead and not sparing the horses (at Bonneville and similar salt flats).  It's not coincidental that Richard Jenkin's land yacht (and outright wind powered speed record) was also set at Ivanpah.

And besides, I'm currently malingering (ooh, my poor back and etc).

But there are other kite buggy records which can be set which don't require waiting for wind or special locations , or even having a functional right shoulder.

And it is the silly season, so I've just set one:

                                                                    8.8km per hour!!

Which might not seem very fast, but this kite buggy was not kite powered, or even wind powered; it was driven by a Stirling engine- and an unpressurised one at that.  And though I'm not yet booking Bonneville, with further development, even 15km/hr might be achievable.

Stirling engines were first developed in their current form by the eponymous Robert Stirling before 1816.  Their principle of operation is to serially expand and contract (by alternately heating and cooling) a lump of gas (air at atmospheric pressure in primitive versions, hydrogen or helium at very high pressures in more pretentious examples).

By the immutable rules set by Sadi Carnot's second law of thermodynamics, in theory Stirling engines can achieve the maximum efficiency attainable by any heat engine - better than steam engines, gas turbines or even the cleverest diesel.

 Which makes them almost fatally alluring for engineers.

Unfortunately.

Because in practice,  Stirling engines generally fail to come up to even steam engine standards of efficiency and their development has not yet provided the world with anything of marked social utility, while consuming multiple careers and sucking up billions of dollars of R and D money that could have been more productively applied elsewhere.

But (I'm excusing myself here); the Stirling powered buggy didn't cost billions.

And granted, this bit of silliness did require a month or so for making the engine (number 12 in a series that's now passing 15) and 2 days for fitting it into the buggy; time stolen from kite building- but hey, kites don't rate that high by social utility either.

Though it's not my, or the first attempt at alternative power for kite buggies: 

Back in 2003 I fitted a Rover gas turbine to one for our xmas time "Great Race".  It did move along under its own power, but only just; on account of its being a gas turbine rather than a pure jet, so not exactly optimised for thrust.  But, entertainment value being the criteria by which Great Race entrants are judged, it had the twin virtues of being very loud and of burning even more fuel for less effect than my latest effort (which seems hardly possible).  Though I never thought of this at the time, unless there's someone out there who's even sillier than I am- which seems highly unlikely- this buggy established a world speed record for gas turbine powered kite buggies which is likely to stand for some time.  I'll claim 5 km/hr.

And,  Andreas Fischbacher entered a sort of hybrid electric buggy in 2008's "Great Race".  It used an electric drill geared to the front wheel, driven by a petrol powered generator in a trailer behind.  Though not conspicuously fast, it was a finisher as well as a starter (a level of performance that many Great Race entrants don't achieve) and was especially entertaining because of Andreas's on-the-move chain re-fitting system - which generated some lively side bets as to how many fingers he would still have when he crossed the finish line.  A video of this race has now had more than 36,000 youtube views.

Whatever speed it did achieve, this is another world record for sure.

And knocking around the buggy shop here somewhere is a kite buggy fitted with a small two stroke engine (from a weed eater I think) which can sometimes be seen scooting around the kite field- and, so it's rumoured, also around the town on occasion (but perhaps we shouldn't be too clear about this).

But to get serious (had to happen sooner or later), last week's Great Race  was the launch platform for a truly functional hybrid buggy (kite/electric).  Ably driven by Petra Haupt,  It/they  would have won easily but for deliberate obstruction by "connections" of other entrants and that the batteries (48volt) were a bit flat on account of all the yahooing around it had done already that day.   Easily capable of more than 20km/hr, with impressive slope climbing torque, and an at least 20km range,  the "motor wheel" that this buggy  has regenerative braking (the wheel motor functions as a generator and re-charges the batteries when used for braking). 

Not since George Pocock (the 1820's father of kite traction) provided space for a small horse in the rear of his charvolant  (kite powered wagon) has there been such a truly practicable solution to occasional lack of wind. 

Best wishes for a great 2013;

Peter Lynn, Ashburton, January 1, 2013.

PS.  How fast could a bungy powered buggy go?- would the sound barrier be limiting?