The plans are provided as a CADKEY file (right-click on the link to download, then unzip), which may be viewed, scaled and printed with the free CADKEY viewer. Alternatively, they may be viewed and printed as a PDF file, scaled for printing on A4 paper. But you will do best to print it on a laser printer and enlarge it on a photocopier.
Assembly instructions are given in PDF format.
Adi Shavit has details of the original Chupp patent (long since expired) on his Kite Patent Blog.