When I was 14 or so I built a glider with my friend Alex. It was based on a book that I got for about 3 dollars from the library disposal box. It took all summer to build and then we drove out to Murawai to test it. I remember what convinced us to build it was a picture of a bamboo butterfly held together with masking tape. It flew but it didn’t survive the first test flight. As soon as I got air born the cleats holding the sail tore away. I have memories of being chased by an angry cow at the launch site that didn’t like the look of the glider. And thankfully we paid close attention to the lesson of Otto L. All bolt shanks outwards!