Another Rowland errata site is maintained by Philip Le Riche.
For instructions on assembling the kites look at my building tips page.
I have build this kite in original size and it flies very well. For more lifting power in slow wind it is better to make it upscaled to 1.5. Page 57: - Front means the bottom side of the canoppy. - Figure 6-9a: Leave the fabric longer for sewing the trailing edge. Page 58: - Back means the top side of the canopy. - Figure 6-10a: Calculate the position of the vents to the leading edge. Leave the fabric longer for sewing the trailing edge. - Figure 6-10b: The length of the fabric is 142cm. Leave the fabric longer for sewing the trailing edge. After finishing all the sewing you make the jet chute by cutting off fabric and hem the edge. - Figure 6-11b: change the height of the trailing edge from 23cm to 13cm. The end of the upper line is about 2cm left from the end of the lower line. (My height of the trailing edge of the center rib is about 12cm). I think this point is not so critical. Page 59: - Figure 6-13: The most difficult think is to fix the inner flare and the inner rib to the bottom centre of the canopy. Make all sewings with start from the leading edge, even if it is much easier to start with the trailing edge. All mistakes will go to the trailing edge and will disappear by hemming the trailing edge. (I have not used binding tape for the trailing edge on any of my flowforms. I hem these edges.) Page 60: - Figure 6-15: This kind of briddling is better to set the correct flying angle. The 4 chambers in the middle are open at the trailing edge. I have cut the upper side of the canopy round like on the picture. The bottom side of the canopy is straight.
In "Soft Kites and Windsocks" by Jim Rowlands (St. Martin's Press,
1992), beginning on page 57, is a set of plans for a Flowform, with a
sail area of just over 18 square feet. While building one of these in
December 1995, I found several errors in the plans. For the beenfit
of anyone else who might want to build a Rowlands Flowform, here's
what I know about the errors and what I decided to do about them, as
well as some general experience and tips.
The main problem is his description of the shape of the airfoil-style
curve at the back edge of the outer and inner ribs. The most obvious
error is in figure 6-11b ("Inner rib"). Look at the height
measurement on the left, labelled "23 cm", and then look at the one on
the right, labelled "22.5 cm". The "23 cm" is obviously drawn much
smaller than the "22.5 cm"! So it's obvious that something is amiss.
Next, try taking a piece of graph paper, and plotting a curve based on
the numbers in Table 1 ("Aerofoil"). The resulting curve does indeed
look like an airfoil, but it does not look much like Figure 6.11a.
Table 1's airfoil is flatter. So, which one is right?
If you measure the length of the airfoil curve itself, from leading
edge to trailing edge, the length of the Table 1 airfoil is about
137.5 cm. For the Figure 6.11a airfoil, the length is about 141.5 cm.
Now, this curve is going to get sewn to the edge of the back of the
flowform. Figure 6.10a says that the length of the edge of the back
is 142 cm. Since this closely matches the Figure 6.11a airfoil, I
decided to treat Figure 6.11a as correct.
Also, if you look at the length of the curve on the back edge of the
inner rib in Figure6.11b, it comes out to 114.5 cm, which is
satisfyingly close to the 115 cm that it ought to be in order to match
the stitching lines on the back of the kite in Figure 6.10b (142 cm -
27 cm). I consider this further evidence that the drawings are right
and the table is wrong.
Here are new entries for Table 1, which produce the shape of Figure
6.11a.
0 22.5
5 26.0
10 29.5
15 32.0
20 34.7
30 37.48
40 38.86
50 39.21
60 38.17
80 31.23
100 20.13
120 4.34
125 0.0
Alternatively, you could use the original Table 1 and adjust the rest
of the kite. I have no idea whether this would produce a
better-flying or worse-flying kite.
I have not build that kite, only noticed those errors. Page 54: - Figure 6-2a: change length 95cm to length 85cm. But leave it longer for sewing the trailing edge. - Figure 6-2b: change length 94cm to length 84cm. - Figure 6-3: change length 94cm to length 84cm
I made the Flowform from this book with great success, so I went for broke and made the Rainbow Parafoil. Two weeks work, and 18 months of rebridiling later I finally got to speak to the "designer". His comments - Don't make the rainbow it will never fly, the profile shape is wrong!!!! This book is still on sale without any warning or correction, BEWARE bad plans
Don't build the "CROWN-RIGGED RAINBOW". I now have meet two people who like me spent many hours making it only to find it won't fly. We all built them exactly to the book, and the kite is so unstable it dosn't stay in the air long. I even got Stretch Tucker to try to trim mine he gave up after half an hour and suggested that instead of scrapping it, I send it to Jim Rowlands to fix. It looks good on the front cover of the book, but the photo must have been taken with a fast shutter before it crashed. I hope this has saved you some time and money.
This kite I build in original size. It is not a stable flier, but funny to see. I have tried to use the kite without spare in the flukes, but it was not successful. Page 63: - Figure 7-2a: Distance flukes from trailing edge I choosed 7cm. Distance flippers from leading edge I choosed 75cm.
Several figures in Table 1 (Rib Shape) are wrong as follows (erroneous figures in brackets): 20.0 23.5(24.0) 1.0 25.0 24.0 0.5(0.0) 30.0 24.5 0.0(blank) 65.0 28.5(29.0) 112.0(102.0) 0.0
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