The 1-7 is all metal except for the fabric covering of the fuselage, tail surfaces and rear portion of the wing. The wing is of single-spar, single-strut design with metal-covered leading edge. All material is aluminum alloy except the fittings and bolts. The fuselage is of rugged steel tube with aluminum fairing members. It has a 5x4 air wheel landing gear with front and tail skids. The tail surfaces are built of formed aluminum alloy members, the fin being cantilever and the stabilizer braced by single struts. The absence of wires and the use of single struts make assembly quick and easy.