I guess thoughts of keeping a kite log book crossed my mind during the early days of the My Best Kite website. But as things got busier and Flight Reports became a regular occurrence, thoughts of keeping a detailed log faded. And then...
Years later and out of the blue, so to speak, a visitor made a suggestion. It could even be called a gentle criticism - I wasn't promoting log-keeping! He had a point.
We kite-fliers are pilots, and pilots of all descriptions keep logs.
In my own experience, that included piloting sailplanes, hang gliders and paragliders. And even radio controlled model aircraft and virtual airliners in a simulation! So why not keep a log for kites?
The sheet made available here is meant to be used for a single flight. You can either build up a collection of filled-out sheets or print out a whole lot of blanks and make them into a pad or log book.
My Flight Reports tend to include all the information described below, but not always all of it in the one report. A real Log is more concise and yet comprehensive at the same time. Reviewing the info later is a breeze, compared to reading entire Flight Reports!
So what do you record in a kite log book?
There's the obvious piece of flying data - launch and landing times! At some convenient time, these can be subtracted to give duration, or 'air time'. Plus of course the date. But others come to mind which would be of particular interest to kite fliers...
Where were you flying? The data might point to some interesting differences in performance for a particular kite - where the only difference was the location. For example, the smooth air coming off the ocean will give you an accurate idea of just what kind of flight angles your kite can achieve without the help of rising air!
Another one - at what constant wind speed does the kite get forced into instability?
If you are keen enough to consider using a kite log book, I'm sure you have more than one kite in the bedroom or back shed! So you need to mention which one was being flown.
Some of the data suggested below will paint a fascinating picture of the strengths and weaknesses of various kite designs. But only after you have methodically recorded the data for some time. The more kites flown, the longer it will take, of course.
Max Flight Angle
This refers to how high the kite has risen, in terms of the angle from horizontal.
At launch, this angle is close enough to zero. If rising air takes the kite directly overhead, this angle is 90 degrees. Anything in between can be estimated to the nearest 10 or 15 degrees. To the nearest 5 if you are really good!
OK, lazy data loggers might stick to the simple 4-point system - N, E, S or W!
Moving up a notch, most of us are probably comfortable with the 8-point system - N, NE, E, SE, S, SW, W, NW.
Then of course, as some would be aware, you could use the 16-point system - N, NNE, NE, ENE, E, ESE, SE, SSE, S, SSW, SW, WSW, W, WNW, NW, NNW. If you can orient yourself accurately enough without the aid of a compass! It can get a bit tricky in the midst of suburbia, where roads don't always line up precisely with the four main directions.
Finally, I'm not sure that there would be much point in going The Full Monty with recording the average wind direction with an electronic wind vane. Perhaps down to the nearest degree! But it's up to you.
Average Wind Speed
I often use a wind meter to record wind data on the day. However, it is inevitable that these figures are only relevant to the launching phase of the flights.
Once aloft, kites get exposed to higher wind speeds and smoother air. With few exceptions in my experience. Although, come to think of it, wind straight off the ocean can be exceptionally smooth, even at shoulder height!
In these days of easy access to live online data, weather stations are useful. These typically record wind speeds at least 5 meters above the ground, and in an exposed location. Thus giving a much more accurate picture of the winds your kite is actually flying in.
Of course, using weather stations absolutely relies on having one or two of them in your own geographical region. You can either go with the figures of the nearest one, or even take the average of two stations if you happen to be roughly half-way between them.
Max Gust Speed
My comments regarding average wind speed in the paragraph above relate equally well to measuring the maximum gust strength of the breeze. At ground level, both the average speed and the gust strength will generally be a lot less than at, say, 300 feet altitude.
Max Line Out
This is easy if you have done a little line preparation beforehand. I mark mine in 15 and 30 meter (50 and 100 feet) increments. Hence it's not hard to keep track of how much line you have out, to the nearest 15m or 50ft anyway.
Max Line Tension
I use a set of mechanical spring scales, which records up to a whopping 50 kilograms. Even my hardest-pulling kite has only recorded 18kg though.
The hook at one end of the scales takes 5 or 6 wraps of flying line, while the kite is in flight. Then it's just a matter of holding the ring at the other end of the scales and reading off the tension. Hang on to it for half a minute or so. What was the highest reading?
Hand-held electronic devices for weighing luggage can also be used.
In this section, write down anything at all that seems worth recording in your kite log book. For me, bird behavior around the kite sometimes features! But it could be anything at all that strikes you as memorable or useful to know, on the day.
Just to make things easier for you, here's a Kite Log Book Sheet as a downloadable PDF file. The beauty of this is that you can print off as many copies as you like, nicely formatted, by selecting File | Print... from the menu bar. Staple copies together as a pad if you wish.
You might need to install the free Adobe Reader on your computer, if you have not used PDFs before. Don't forget to un-check the box if you don't want the free utility software installed!