I�m often asked how long a larger kite can be expected to last. And my answer is that most big kites don�t die of old age. They die from trauma. Trauma means accidents � fences, trees, cars, or bodies of water.

Now that said, I�ve seen big kites trashed and patched back together as good as new. I�ve seen legs replaced on bears, seams tucked in on Meanies, and a run-away Penguin with thirty feet of rips sewn back together in the festival tent and back in the air the next day.

So if they can be fixed, and if they wear out slowly, what really is the lifespan on a larger kite? We asked that question of Peter Lynn a while back and here is his answer.

What flying life can be expected from a maxi show kite?

First of all, a definition. I define maxi kites as those weighing approximately 12 kilograms (26 pounds). Peter Lynn Kites Ltd scales each new design until it's weight is in the 11 to 15kgm range and defines these as maxis. Dimensions are then halved from this for midis, halved again for minis. Like for many standards of measurement this derives from something that's apparently unconnected, in this case airline baggage allowances.

At 15 kilograms it is possible to pack two maxi kites in one bag and stay under the 32 kilogram (70 pound) limit that used to apply for journeys to and from the USA. Now the standard bag weight has been dropped to just 23kgms (50 pounds), but the maxi kite definition has stuck. Kites larger than maxis are called super maxis and (for Guinness record sizes), megas.

Kites deteriorate because of 2 factors; ultra violet light (which causes degradation of the fibres, coating and dyes) and the km's run of wind that pass them, weighted towards stronger conditions. Generally for this though, I use the cruder measure of days flying. Thrashing wind causes coatings to flake away, increasing porosity (but which, paradoxically, increases tear strength). It also abrades adjacent fibres eventually reducing fabric strength.

In my experience, actual damage doesn't cost kite life. It may, for those who are concerned with intangibles, make a kite less desirable to own but it won't affect its life and, after repairs, won't significantly effect the kite's appearance while flying.

In a lifetime of kite abuse, the most serious damage I've ever done has taken little more than a day in the factory to repair- which is equivalent to less than 10% of it's value when new.

I have seen kite fabric fall apart because of UV, but with reputable fabrics, this takes perhaps 1000 or more hours exposure. Much more rapid- and more annoying, is colour fading. Fluoros are the worst- stay away from them for display kites that need to last, no matter what the graphics temptations are. Some other colours are also susceptible to fading, usually the lighter colours like yellow.

There is no predicting this except by experience or actual testing- every fabric type from each manufacturer has it's own quirks. It's also useful to consider where a kite will be flown. In Australia or NZ, some colour fade can be detectable after just a week's flying, whereas the same kite would not show any signs until after at least a month or more in Europe (even in the Mediterranean).

I now find that the useful life of a maxi show kite is more than 300 flying days. At this it will still generally be presentable and suitable for all winds. Even just a few years ago, perhaps 150 flying days was the tipping point. This gain has come from developments in construction and from the use of better fabrics, particularly those combining polyurethane and silicon in the coatings- usually at about an 80/20 ratio. This fabric stands wind damage better, appears to be generally more colour fast, is much more resistant to tearing and is easier to pack than harder finishes. It's also water resistant.

On a straight line depreciation basis therefore, each day of flying now costs a maxi kite owner about NZ $25 (US$19).

Peter Lynn
San Francisco, July 3 2007