Complex sentence: The Rutan Aircraft Factory sold over 600 plan sets for the VariViggen to homebuilders, and eventually about 20 of the aircraft were built, with fewer than five currently still flying, one of which crashed in New Brunswick, Canada in September 2006.
Split into simpler sentences: The Rutan Aircraft Factory sold over 600 plan sets for the VariViggen to homebuilders, and eventually about 20 of the aircraft were built. Fewer than five are currently still flying following the crash of one in New Brunswick, Canada in September 2006.