The Quicksilver, by Eipper-Formance (designer Bob Lovejoy?), was the first production rigid wing design. It later had a small motor added to it and became one of the first foot-launched ultralights. As an ultralight, its various further modifications made it probably the most widely sold model. However, as a hang glider, it did not enjoy wide success, as it was heavier and more complicated than the standard rogallo designs of the time.
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