The major difference between free-flight and radio-controlled scale models is that all the adjustments to the flight path of the former must be made before release. Free flight models must be capable of stable flight, whether under power or on the glide, without the need or the opportunity to carry out in-flight alterations. This is a challenge most surely met by lightly loaded, slow-flying models based on full size machines having those characteristics, best typified by early bi-planes.

I remember an instance at one point, during my late twenties or early thirties, when I wondered what it would be like to hear voices. At that time I was slightly acquainted with a schizophrenic named Mike, who told me that he had Jesus in his head. That was his hallucination. Jesus talked to him, apparently. I remember wondering at the time what it would be like to have Jesus talking in my head. What would it be like, I wondered, to be schizophrenic for a day? It turned out to be more terrifying than I ever imagined.