Gliding towards free flight
After my latest attempt at rubber powered free flight, an attempt that we can best describe as having 'mixed results'. Previous attempts ie the "Cardboard Cessna 180" flew but were not durable enough.
Reviewing past posts and the kind comments in this forum, I decided to go back to basics and build simple gliders with 12" -14" span ( about 40 cm) for a start, to work out the aerodynamics and crash resistance.
Initial tests have been encouraging, hope to post some pix of an all card glider here.
What I have learned so far:
- A model that glides slowly has a better chance of being powered by the weak, short burst of power that the rubber motors I am using provides
- A model that requires a powerful throw to fly is a less likely candidate.
- For a 30 cm long model, a 20 cm solid card wing is just marginal, and is is surprising to me what a difference card is compared to foam or balsa
- Since it is diffult to keep the weight down, better try building a larger model, as the relative density of the model goes down, and the larger area will support greater weight. Some rubber powered models weigh 100 g or more with a 28" : 70 cm plus wing.
- The crash resistance and durabilty I require absolutely needs stronger materials - no long tall grass here.
Admittedly I should have taken the advice and built a non - scale model first!