As you may have guessed from the fact that the title refers to the ‘first test flight’, it wasn’t wonderfully successful.
As you see from the video, the plane quickly veers to the left, flips on its back and drops like a stone.
One potential issue is with the weight. The flightpath suggests that the centre of gravity is too far back, but the problem could be that the nose is too light rather than the tail too heavy. However, all the talk on the balsa modelling forums I have skimmed is about keeping the model as light as possible. Clearly more reading and experimentation is needed. As a result, you may see my Book Diary dominated by volumes on free flight aerodynamics and the like over the next month or two.
Further examination of the model post-test flight revealed that the whole tail section was slightly twisted, which almost certainly contributed to the model flipping as it flew. I think this problem may have its roots in the original construction rather than crash damage. Therefore, the plane may well be doomed from the outset, and I will have to consider the implications before getting too far with the next flying model. Before that though, I will repair this one (the undercarriage took a bit of a battering and needs re-glueing), and try to adjust the tail surfaces to compensate for both the natural tendency to diverge from straight-and-level flight caused by the rotational effect of the propeller and my shoddy workmanship.
The only possible factor which could have led to such a disappointing first flight which is outside of my control would be the wind. As you can see in the video, it’s a moderately breezy day. Perhaps I should have waited for a calmer period. I also launched into the wind (as much as I could – it was swirling a little in the enclosed garden) which should give the plane more lift. The lightness of the plane, combined with the wrong centre of gravity could have contributed to it gaining the lift too quickly and flipping over as it did.
All in all, a sobering experience, but one which has made me more determined to get it right in future. I suspect my repairs will be somewhat in vain and this model will end up on display only, but even if that is the case, I have learned important lessons from it.