A discussion forum chartered to support builders and pilots of Janowski designed aircraft including the Don Quixote, Polonez, Eagle, Marco, and Fregata.
The J-1B plans I just sold had information on a foam and fiberglass option. I believe it still used wood for longerons and spars, but used foam sheets and
It has more modern versions made of composites, they are called J-5 and J-6, but no plans are offered. See: http://www.angelfire.com/ks2/janowski/ Aluminum