August 2006

Newsletter, August '06

The Fortunate Life.

Health, good friends, lots of toys, financial independence, no time clock, no boss, interesting projects and achievable challenges - oh, and youth of course.

What a fortunate life.

Actually I didn't plan it to be this way, it's just sort of happened.

Happiness!

Well actually not. The last twelve months has been more than a bit frustrating.

The underlying cause?:- Not enough progress on kite developments -and more to the point, not having convenient excuses for this anymore.

Except maybe that I've been traveling too much -half the year sans sewing machine and workshop.

Or if this doesn't sound convincing, then how about that I haven't been traveling enough?- kite events are a great source of inspiration and I always arrive back just bursting with new things to try.

What I am certain about though is that the wind here is impossible for kite testing,  a test of character which I completely fail. 

It's so fundamentally annoying to build something exciting then have it sit untested for weeks; to eventually fly by running around in circles 'cos there's no wind, or have it blow out in a gale (usually at night when it's also snowing) which is the only other sort of wind we get here from April to October.

Except for our nor'westers of course- which provide none and too much simultaneously.

How many kites have I consigned to the scrap without my ever finding out that they did work?.- more than a few I reckon. 

Today I again vented more than a few expletives at the sheer bloody unfairness of it.

Access to wind is solvable though:

The Wright Bros, abandoned Dayton for lack of good wind and set up summer camp at Kill Devil Hills.

Pete shifted from Ashburton to the beach at Christchurch and then to Newcastle in Aust.

I'm stuck here in Ashburton-  by friends, family, property, businesses - and toys- so all I can do is whinge.

Thanks for listening.

But enough of that,  there has at last been some progress..

Two line traction kites of fifteen years ago had no power range- the flier just had to take (and try to survive) whatever pull the kite sent down the line.  This is like a car with steering but  no gears, no clutch, no accelerator and no brakes.  Four line kites added brakes, but it's only with the advent of LEI's, Arcs , and some 'foils (a little bit) that we gained an accelerator- though still an ineffectual one.   LEI's with fifth line systems and Bow kites bought us the clutch as well but whenever it's activated, the steering disengages.

In short, the development process started so ably  by George (Pocock, early 19th cent) still has a long way to go before we have really efficient, safe and easy to use traction kites.  We're about where the car was with the Model T , or maybe not quite. 

It's a wonderful challenge to be involved with.

Twelve months ago I began to focus on a principle called adaptive profile (AP) .

AP  describes kites for which the profile changes with angle of attack. The principle is that the appropriate profile for minimum pull- when very low angles of attack  and max. luff resistance are required, is not the same as the best profile for max . pull -  when high angle of attack and good stall resistance are desired.  This is obvious of course- but kites do not yet have this ability to any great extent because there are so many variables and no available analytical technique for finding a combination that works-  if there is one-  which can't be known until it's found.  The angle of attack  has to match the centres of pressure of the changing profiles not only at the extremes but at every increment between.

By Oct '05 there had been excellent  progress and I was certain then that all our commercial products would have been re-shaped by now as a result.  C Quad and bridled foil versions were showing great promise and some Arc developments were not far behind.

But the devil, as usual, was in the detail; it's taken longer than I expected-  hence the frustration.

I still only have one style of AP kite really working, an AP bridled 'foil.   AP versions of the C Quad, Arc,  and other styles are still stuck at the "showing promise" stage.   

The  AP bridled 'foil is working well though.   It has substantial de-power, no bad habits and is easy to fly.

It's bridle has no pulleys or sliding loops and requires about the same total length of line in it's construction as for conventional 4 line 'foil bridling.

And it seems to be a generic solution that will work for bridled foils across all sizes and for styles ranging from beginner through to extreme.

.  

I'll have an AP 'foil with me on my next trip: Bintaloo (Sarawak), Bristol, Dieppe, Barcelona, Seattle (Drachen Kitesailing Seminar) Ashburton (briefly for a change of underpants) then Broome(on the hot side of Aust. , my last overseas event this year, whooee! ) . 

Come and have a fly and see what you think.

Peter Lynn,

Ashburton , July 31 '06